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Cited by 409Tissue Engineering and Regenerative Medicine3D Printing in Biomedical ResearchHydrogels: synthesis, properties, applications

Towards organoid culture without Matrigel

Open access
Kozlowski, Mark T., Crook, Christiana J., Ku, Hsun Teresa·2021·Communications Biology
DOI 10.1038/s42003-021-02910-8PMC PMC8664924
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Abstract

Organoids—cellular aggregates derived from stem or progenitor cells that recapitulate organ function in miniature—are of growing interest in developmental biology and medicine. Organoids have been developed for organs and tissues such as the liver, gut, brain, and pancreas; they are used as organ surrogates to study a wide range of questions in basic and developmental biology, genetic disorders, and therapies. However, many organoids reported to date have been cultured in Matrigel, which is prepared from the secretion of Engelbreth-Holm-Swarm mouse sarcoma cells; Matrigel is complex and poorly defined. This complexity makes it difficult to elucidate Matrigel-specific factors governing organoid development. In this review, we discuss promising Matrigel-free methods for the generation and maintenance of organoids that use decellularized extracellular matrix (ECM), synthetic hydrogels, or gel-forming recombinant proteins.

AI snapshot

Written from the paper’s full text.

TL;DR

This review argues that Matrigel’s undefined complexity—more than 1800 unique proteins, lot-to-lot variation, poor mechanical control, and mouse-derived immunogenicity—motivates Matrigel-free organoid culture. It surveys decellularized ECM, synthetic hydrogels, and gel-forming recombinant proteins/peptides, emphasizing stiffness and biochemical cues as key design parameters.

Key findings

  • Matrigel is chemically undefined and mechanically heterogeneous; proteomic analysis shows >1800 unique proteins, and its mouse sarcoma origin raises immunogenicity concerns for human transplantation. Decellularized ECM preserves native chemical and mechanical cues but is limited by donor availability, batch variability, difficult property control, and residual undefined factors.
  • Synthetic hydrogels allow independent tuning of mechanics and chemistry, and stiffness strongly affects organoid fate: intestinal organoids formed optimally at ~190 Pa with laminin-111 functionalization; neural tube organoids at 2–4 kPa; brain organoids showed forebrain fate at ~300 Pa versus hindbrain fate at ~1000 Pa; cardiomyocyte differentiation was favored at 700 Pa.
  • Recombinant and peptide matrices can be molecularly defined and tunable. An artificial elastin-like polypeptide with laminin sequence (aECM-lam) supported endocrine/acinar pancreatic organoids from ductal progenitors; elastin-like protein matrices at 180 Pa gave intestinal organoid-forming efficiencies comparable to collagen I; RADA-16 3D culture activated p21-activated kinase in an Alzheimer’s disease neuronal model.
  • Matrix-free suspension methods also exist, such as keeping human embryonic stem cells at 70 rpm to generate beta-like cells, but the review focuses on replacing Matrigel with alternative matrices.

Methods

  • Narrative review; no primary experimental data are reported. It synthesizes published studies on Matrigel-free organoid culture across tissues including liver, gut, pancreas, brain, heart, and others.
  • Organizes alternatives into decellularized ECM and naturally derived biomacromolecules, synthetic hydrogels, and gel-forming recombinant proteins/peptides; includes Table 1 summarizing advantages/disadvantages and Table 2 listing ideal elastic moduli for several organoid types.
  • Discusses specific material properties, organoid outcomes, and cited methods from the literature; no systematic search strategy, inclusion criteria, or meta-analysis is described.

Limitations

  • Stated by the paper: decellularized ECM is donor-limited, batch-variable, chemically undefined, and difficult to modify mechanically; collagen-based methods may require feeder cells and cannot easily separate mechanical from chemical changes; synthetic hydrogels may need functionalization, can degrade into cytotoxic by-products, require cytotoxic initiators, or trigger foreign body reactions; recombinant proteins may be hard to express/refold, costly, immunogenic, or contaminated with endotoxin.
  • Stated by the paper: Matrigel-free techniques have been used in only a narrow range of target tissues, and expanding tissue types is needed for broader acceptance.
  • Evident from the text: as a narrative review, it lacks a systematic search or quantitative synthesis, and its conclusions depend on cited primary studies rather than new experimental validation; many cited findings are from in vitro or animal models, not clinical translation.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1038/s42003-021-02910-8

Cites

Statistics

Nothing to recompute.

Claims the paper makes

0 of 243 cited sources checked · 0 supported · 0 flagged

  • Premisecitation

    The mechanical properties of Matrigel-based culture systems cannot be easily separated from their chemical cues.

    “The mechanical properties, such as elastic modulus, pore size, stress relaxation, and creep56–59, cannot be easily separated from the chemical cues in the Matrigel-based culture systems.”
    Quote in the paperSubstantial claim0 of 4 sources checked
    • cites [56] Chaudhuri, O. Viscoelastic hydrogels for 3D cell culture. Biomater. Sci. 5, 1480–1490 (2017). source

      Not checked in the free run.

    • cites [57] Slater, K., Partridge, J. & Nandivada, H. Tuning the Elastic Moduli of Corning® Matrigel® and Collagen I 3D Matrices by Varying the Protein Concentration: Application Note https://www.corning.com/catalog/cls/documents/application-notes/CLS-AC-AN-449.pdf (2018).

      Not checked in the free run.

    • cites [58] Nemir, S. & West, J. L. Synthetic materials in the study of cell response to substrate rigidity. Ann. Biomed. Eng. 38, 2–20 (2010). source

      Not checked in the free run.

    • cites [59] Miroshnikova, Y. A. et al. Engineering strategies to recapitulate epithelial morphogenesis within synthetic three-dimensional extracellular matrix with tunable mechanical properties. Phys. Biol. 8, 13 (2011). source

      Not checked in the free run.

  • Premisecitation

    Gut organoids cultured in Matrigel lack the characteristic architecture of mammalian intestines.

    “Furthermore, Matrigel may not contain all of the necessary components for proper organoid formation; gut organoids cultured in Matrigel lack the characteristic architecture of mammalian intestines, which could be due to a sub-optimal amount of laminin-511 and the absence of other cell types such as mesenchymal cells49,50.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [49] Mahoney, Z. X., Stappenbeck, T. S. & Miner, J. H. Laminin alpha 5 influences the architecture of the mouse small intestine mucosa. J. Cell Sci. 121, 2493–2502 (2008). source

      Not checked in the free run.

    • cites [50] Gjorevski, N., Ranga, A. & Lutolf, M. P. Bioengineering approaches to guide stem cell-based organogenesis. Development 141, 1794–1804 (2014). source

      Not checked in the free run.

  • Premisecitation

    Mechanical properties in three-dimensional culture systems can have large effects on cell, organoid, tissue, and organ development.

    “Finally, it has become increasingly clear that the mechanical properties in three-dimensional (3D) culture systems can have large effects on cell51, organoid52, tissue53, and organ development54,55.”
    Quote in the paperSubstantial claim0 of 5 sources checked
    • cites [51] Engler, A. J., Sen, S., Sweeney, H. L. & Discher, D. E. Matrix elasticity directs stem cell lineage specification. Cell 126, 677–689 (2006). source

      Not checked in the free run.

    • cites [52] Dahl-Jensen, S. & Grapin-Botton, A. The physics of organoids: a biophysical approach to understanding organogenesis. Development 144, 946–951 (2017). source

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    • cites [53] Nelson, C. M. & Gleghorn, J. P. in Annual Review of Biomedical Engineering Vol. 14 (ed. Yarmush, M. L.) (Annual Reviews, 2012). source

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    • cites [54] Murphy, W. L., McDevitt, T. C. & Engler, A. J. Materials as stem cell regulators. Nat. Mater. 13, 547–557 (2014). source

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    • cites [55] Vining, K. H. & Mooney, D. J. Mechanical forces direct stem cell behaviour in development and regeneration. Nat. Rev. Mol. Cell Biol. 18, 728–742 (2017). source

      Not checked in the free run.

  • Interpretationreasoning

    The undefined nature of Matrigel makes it difficult to identify the signals necessary for organoid structure and function.

    “The undefined nature of Matrigel makes it difficult to identify the signals necessary for organoid structure and function; this difficulty is compounded by lot-to-lot variations of Matrigel45–48.”
    Quote in the paperSubstantial claim
  • Premisecitation

    Many organoids reported to date have been cultured in Matrigel.

    “However, many organoids reported to date have been cultured in Matrigel, which is prepared from the secretion of Engelbreth-Holm-Swarm mouse sarcoma cells; Matrigel is complex and poorly defined.”
    • Also stated in: § Introduction · plain
      “Many organoids have been cultured in Matrigel, a material derived from the secretion of Engelbreth–Holm–Swarm mouse sarcoma cells and enriched for extracellular matrix (ECM) proteins27.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [27] Kleinman, H. K. & Martin, G. R. Matrigel: basement membrane matrix with biological activity. Semin. Cancer Biol. 15, 378–386 (2005). source

      Not checked in the free run.

  • Classified as probably not a substantial claim. 19
  • May combine two claims. 64

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    There is an emerging need to develop Matrigel-independent organoid culture methods.

    “Given these limitations, there is an emerging need to develop Matrigel-independent organoid culture methods.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Matrigel originated from mouse cells, which hampers its use in human clinical transplantation due to potential immunogenicity.

    “Finally, the fact that Matrigel is originated from mouse cells hampers its use in human clinical transplantation due to potential immunogenicity18.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [18] Schneeberger, K. et al. Converging biofabrication and organoid technologies: the next frontier in hepatic and intestinal tissue engineering? Biofabrication 9, 013001–013001 (2017). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    ECM proteins provide signaling cues, serve as an adhesive substrate, and sequester growth factors in organ development.

    “In organ development, ECM proteins provide signaling cues, serve as an adhesive substrate, and sequester growth factors (Fig. 2)62.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [62] Hussey, G. S. D. & J.L.; Badylak, S. F. Extracellular matrix- based materials for regenerative medicine. Nat. Rev. Mater. 3, 159–173 (2018). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Matrigel is complex and poorly defined.

    “Matrigel is complex and poorly defined.”
    • Also stated in: § Introduction · plain
      “Despite its versatility and affordability, Matrigel is extremely complex; proteomic analysis shows that it contains more than 1800 unique proteins44.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [44] Hughes, C. S., Postovit, L. M. & Lajoie, G. A. Matrigel: a complex protein mixture required for optimal growth of cell culture. Proteomics 10, 1886–1890 (2010). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Matrigel is prepared from the secretion of Engelbreth-Holm-Swarm mouse sarcoma cells.

    “Many organoids have been cultured in Matrigel, a material derived from the secretion of Engelbreth–Holm–Swarm mouse sarcoma cells and enriched for extracellular matrix (ECM) proteins27.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [27] Kleinman, H. K. & Martin, G. R. Matrigel: basement membrane matrix with biological activity. Semin. Cancer Biol. 15, 378–386 (2005). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Growing murine small cholangiocytes in porcine liver ECM gel resulted in the formation of complex, branching structures similar to biliary ducts, and these cells secreted small amounts of bile.

    “Lewis and colleagues observed that growing murine small cholangiocytes (a committed progenitor cell type) in porcine liver ECM gel resulted in the formation of complex, branching structures similar to biliary ducts, and these cells also secreted small amounts of bile.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [77] Lewis, P. L. et al. Complex bile duct network formation within liver decellularized extracellular matrix hydrogels. Sci. Rep. 8, 12220 (2018). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Two factors affect the differentiation of progenitor cells into organoids in collagen-based matrices: the source of seeded cells, and the spatial arrangement of collagen types around the cells.

    “Two factors have been shown to affect the differentiation of progenitor cells into organoids in collagen-based matrices: the source of seeded cells, and the spatial arrangement of collagen types around the cells.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [91] Isshiki, H. et al. Establishment of a refined culture method for rat colon organoids. Biochem. Biophys. Res. Commun. 489, 305–311 (2017). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The choice between the TMDU and Ootani methods should be governed by the source of cells used to generate the intestinal organoid.

    “Isshiki and colleagues reported that the choice between the TMDU and Ootani methods should be governed by the source of cells used to generate the intestinal organoid.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [91] Isshiki, H. et al. Establishment of a refined culture method for rat colon organoids. Biochem. Biophys. Res. Commun. 489, 305–311 (2017). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Decellularized ECM may provide additional cues that promote regeneration of damaged tissue, ultimately supporting the organoid transplant and promoting its function.

    “Decellularized ECM may also provide additional cues that promote regeneration of damaged tissue, ultimately supporting the organoid transplant and promoting its function66.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [66] Yu, Y., Alkhawaji, A., Ding, Y. & Mei, J. Decellularized scaffolds in regenerative medicine. Oncotarget https://doi.org/10.18632/oncotarget.10945 (2016). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Vitrified collagen I has been used for human intestinal organoids and murine renal organoids.

    “Other examples are vitrified collagen I for human intestinal organoids86 and murine renal organoids87, as well as fibrin supplemented with laminin-111 capable of supporting various murine and human epithelial organoids88.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [86] Takezawa, T., Ozaki, K., Nitani, A., Takabayashi, C. & Shimo-Oka, T. Collagen vitrigel: a novel scaffold that can facilitate a three-dimensional culture for reconstructing organoids. Cell Transplant. 13, 463–473 (2004). source

      Not checked in the free run.

    • cites [87] Wang, P. C. & Takezawa, T. Reconstruction of renal glomerular tissue using collagen vitrigel scaffold. J. Biosci. Bioeng. 99, 529–540 (2005). source

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  • May combine two claims.

    Premisecitation

    Cholangiocytes cultured in Matrigel formed cysts, while those in collagen I proliferated and spread in all directions without spontaneously forming structures.

    “In contrast, cholangiocytes cultured in Matrigel formed cysts while those in collagen I proliferated and spread in all directions without spontaneously forming structures77.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [77] Lewis, P. L. et al. Complex bile duct network formation within liver decellularized extracellular matrix hydrogels. Sci. Rep. 8, 12220 (2018). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Collagen I has a high affinity for α2β1 integrin, whereas collagen IV binds more strongly to α1β1 integrin.

    “Collagen I has a high affinity for α2β1 integrin, whereas collagen IV binds more strongly to α1β1 integrin93.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [93] Khoshnoodi, J., Pedchenko, V. & Hudson, B. G. Mammalian collagen IV. Microsc. Res. Tech. 71, 357–370 (2008). source

      Not checked in the free run.

  • May combine two claims.

    Interpretationcitation

    Matrigel alone does not provide all of the needed factors for small cholangiocyte differentiation, whereas a decellularized liver ECM gel appears to be a better alternative.

    “Thus, Matrigel alone does not provide all of the needed factors for small cholangiocyte differentiation, whereas a decellularized liver ECM gel appears to be a better alternative.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Major differences exist in protein compositions comparing decellularized rat pancreatic extracellular matrix to Matrigel; Matrigel contains lower levels of collagen V than are normally present in pancreatic ECM.

    “Using mass spectrometry, Bi and colleagues found major differences in protein compositions comparing decellularized rat pancreatic extracellular matrix to Matrigel; Matrigel contains lower levels of collagen V than are normally present in pancreatic ECM.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [83] Bi, H., Ye, K. & Jin, S. Proteomic analysis of decellularized pancreatic matrix identifies collagen V as a critical regulator for islet organogenesis from human pluripotent stem cells. Biomaterials 233, 119673 (2020). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Perfusing Triton X-100 and ammonium hydroxide through a ferret hepatic vascular network removed cells while preserving the underlying ECM and vasculature and retaining most glycosaminoglycans, collagens, and elastins.

    “In contrast, Baptista and colleagues perfused Triton X-100 and ammonium hydroxide through a ferret hepatic vascular network to remove cells. This method preserved the underlying ECM and vasculature while retaining most of the glycosaminoglycans, collagens, and elastins.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [74] Baptista, P. M. et al. The use of whole organ decellularization for the generation of a vascularized liver organoid. Hepatology 53, 604–617 (2011). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Liver tissue decellularization supported growth and maintenance of rat hepatocytes, but the method relied on mechanical disruption of resected tissue, resulting in loss of organ architecture and vascular networks.

    “Lin and colleagues reported that liver tissue decellularization supported growth and maintenance of rat hepatocytes; however, this method relied on mechanical disruption of resected tissue, which resulted in the loss of organ architecture and vascular networks73.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [73] Lin, P., Chan, W. C. W., Badylak, S. F. & Bhatia, S. N. Assessing porcine liver-derived biomatrix for hepatic tissue engineering. Tissue Eng. 10, 1046–1053 (2004). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The Ootani method uses collagen I gel in which small and large intestinal cells are kept suspended at an air-liquid interface; this method improves oxygenation of the organoid, allows viable murine organoids to be maintained in culture for up to 350 days, and preserves the mesenchymal niche in the organoids.

    “In contrast to the TMDU method, the Ootani method uses collagen I gel in which small and large intestinal cells are kept suspended at an air-liquid interface; this method improves oxygenation of the organoid, allows viable murine organoids to be maintained in culture for up to 350 days, and preserves the mesenchymal niche in the organoids90.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [90] Ootani, A. et al. Sustained in vitro intestinal epithelial culture within a Wnt-dependent stem cell niche. Nat. Med. 15, 1–U140 (2009). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Decellularization approaches have been demonstrated for human kidney, murine kidney, murine heart, human and porcine lung, and porcine testicular tissues.

    “Decellularization approaches have been demonstrated for human kidney67, murine kidney67,68, murine heart69,70, human and porcine lung71, and porcine testicular72 tissues, with each type posing unique challenges.”
    Quote in the paperNot a substantial claim0 of 6 sources checked
    • cites [67] Orlando, G. et al. Discarded human kidneys as a source of ECM scaffold for kidney regeneration technologies. Biomaterials 34, 5915–5925 (2013). source

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    • cites [68] Batchelder, C. A., Martinez, M. L. & Tarantal, A. F. Natural scaffolds for renal differentiation of human embryonic stem cells for kidney tissue engineering. PLoS ONE 10, 18 (2015). source

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    • cites [69] Hong, X. et al. Skeletal extracellular matrix supports cardiac differentiation of embryonic stem cells: a potential scaffold for engineered cardiac tissue. Cell. Physiol. Biochem. 45, 319–331 (2018). source

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    • cites [70] Guyette, J. P. et al. Perfusion decellularization of whole organs. Nat. Protoc. 9, 1451–1468 (2014). source

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    • cites [71] Gilpin, S. E. et al. Perfusion decellularization of human and porcine lungs: bringing the matrix to clinical scale. J. Heart Lung Transplant. 33, 298–308 (2014). source

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    • cites [72] Vermeulen, M. D. V. et al. Generation of organized porcine testicular organoids in solubilized hydrogels from decellularized extracellular matrix. Int. J. Mol. Sci. 20, 5476 (2019). source

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  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    The proteomic profile of the rat pancreas may be very different from that of the human pancreas.

    “One key limitation of this study, however, is that the proteomic profile of the rat pancreas may be very different from that of the human pancreas.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Collagen I has been used to form human colorectal carcinoma model organoids in a 3D culture of rabbit colons and as a support for the culture of human and murine intestinal, stomach, and colonic organoids.

    “Collagen I has been used to form human colorectal carcinoma model organoids in a 3D culture of rabbit colons84 and as a support for the culture of human and murine intestinal, stomach, and colonic organoids85.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [84] Devarasetty, M., Skardal, A., Cowdrick, K., Marini, F. & Soker, S. Bioengineered submucosal organoids for in vitro modeling of colorectal cancer. Tissue Eng. Part A 23, 1026–1041 (2017). source

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    • cites [85] Jee, J. H. et al. Development of collagen-based 3D matrix for gastrointestinal tract-derived organoid culture. Stem Cells Int. 2019, 8472712–8472712 (2019). source

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    Premisecitation

    Alginate is inexpensive, relatively easy to modify and functionalize, biocompatible, and has been used in a wide range of biological and materials applications.

    “Alginate has a number of advantages that make it attractive as a material for further study; it is inexpensive, relatively easy to modify and functionalize, biocompatible, and has been used in a wide range of biological and materials applications106–108.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [106] Chen, X., Zhao, X. & Wang, G. Review on marine carbohydrate-based gold nanoparticles represented by alginate and chitosan for biomedical application. Carbohydr. Polym. 244, 116311 (2020). source

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    • cites [107] Fernando, I. P. S., Lee, W., Han, E. J. & Ahn, G. Alginate-based nanomaterials: fabrication techniques, properties, and applications. Chem. Eng. J. 391, 13 (2020). source

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    • cites [108] Cattelan, G. et al. Alginate formulations: current developments in the race for hydrogel-based cardiac regeneration. Front. Bioeng. Biotechnol. 8, 16 (2020). source

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  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    Decellularized ECM retains the compositional differences observed between basal and apical regions.

    “Decellularized ECM retains the compositional differences observed between basal and apical regions.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Hyaluronic acid and mixtures of hyaluronic acid and chitosan have been extensively used in the growth and construction of neural organoids.

    “Similarly, hyaluronic acid and mixtures of hyaluronic acid and chitosan have been extensively used in the growth and construction of neural organoids111–116.”
    Quote in the paperNot a substantial claim0 of 6 sources checked
    • cites [111] Führmann, T. et al. Injectable hydrogel promotes early survival of induced pluripotent stem cell-derived oligodendrocytes and attenuates longterm teratoma formation in a spinal cord injury model. Biomaterials 83, 23–36 (2016). source

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    • cites [112] Lindborg, B. A. et al. A chitosan-hyaluronan-based hydrogel-hydrocolloid supports in vitro culture and differentiation of human mesenchymal stem/stromal cells. Tissue Eng. Part A 21, 1952–1962 (2015). source

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    • cites [113] Lindborg, B. A. et al. Rapid induction of cerebral organoids from human induced pluripotent stem cells using a chemically defined hydrogel and defined cell culture medium. Stem Cells Transl. Med. 5, 970–979 (2016). source

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    • cites [114] Wu, S. H., Xu, R. J., Duan, B. & Jiang, P. Three-dimensional hyaluronic acid hydrogel-based models for in vitro human iPSC-derived NPC culture and differentiation. J. Mat. Chem. B 5, 3870–3878 (2017). source

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    • cites [115] Lam, J., Carmichael, S. T., Lowry, W. E. & Segura, T. Hydrogel design of experiments methodology to optimize hydrogel for iPSC-NPC culture. Adv. Healthc. Mater. 4, 534–539 (2015). source

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    • cites [116] Bejoy, J. et al. Differential effects of heparin and hyaluronic acid on neural patterning of human induced pluripotent stem cells. ACS Biomater. Sci. Eng. 4, 4354–4366 (2018). source

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  • May combine two claims.

    Premisecitation

    β4 integrin expressed by intestinal organoids is distributed only at the basal surface, while β1 integrin is required for proper apical-basal polarization.

    “β4 integrin expressed by intestinal organoids is distributed only at the basal surface94, while β1 integrin is required for proper apical-basal polarization95–97.”
    Quote in the paperNot a substantial claim0 of 4 sources checked
    • cites [94] Fatehullah, A., Appleton, P. L. & Nathke, I. S. Cell and tissue polarity in the intestinal tract during tumourigenesis: cells still know the right way up, but tissue organization is lost. Philos. Trans. R. Soc. Lond. Ser. B, Biol. Sci. 368, 20130014 (2013). source

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    • cites [95] Lee, J. L. & Streuli, C. H. Integrins and epithelial cell polarity. J. Cell Sci. 127, 3217–3225 (2014).

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    • cites [96] Myllymäki, S. M., Teräväinen, T. P. & Manninen, A. Two distinct integrin-mediated mechanisms contribute to apical lumen formation in epithelial cells. PLoS ONE 6, e19453 (2011). source

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    • cites [97] Co, J. Y. et al. Controlling epithelial polarity: a human enteroid model for host-pathogen interactions. Cell Rep. 26, 2509–2520.e2504 (2019). source

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  • May combine two claims.

    Premisenone given

    Emphysematous or fibrotic lung tissue has hardened and undergone alterations in its architecture.

    “For example, emphysematous or fibrotic lung tissue has hardened and undergone alterations in its architecture.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [118] Wagner, D. E. et al. Comparative decellularization and recellularization of normal versus emphysematous human lungs. Biomaterials 35, 3281–3297 (2014). source

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    • cites [119] Booth, A. J. et al. Acellular normal and fibrotic human lung matrices as a culture system for in vitro investigation. Am. J. Respir. Crit. Care Med. 186, 866–876 (2012). source

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Collagen IV tends to occur exclusively in basement membranes.

    “Collagen IV tends to occur exclusively in basement membranes93.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [93] Khoshnoodi, J., Pedchenko, V. & Hudson, B. G. Mammalian collagen IV. Microsc. Res. Tech. 71, 357–370 (2008). source

      Not checked in the free run.

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    Premisecitation

    Alterations in emphysematous or fibrotic lung tissue can lead to cells failing to survive beyond one week of culture or broad changes in the phenotype of seeded cells that do survive.

    “These alterations can lead to cells failing to survive beyond one week of culture118 or broad changes in the phenotype of seeded cells that do survive119.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [118] Wagner, D. E. et al. Comparative decellularization and recellularization of normal versus emphysematous human lungs. Biomaterials 35, 3281–3297 (2014). source

      Not checked in the free run.

    • cites [119] Booth, A. J. et al. Acellular normal and fibrotic human lung matrices as a culture system for in vitro investigation. Am. J. Respir. Crit. Care Med. 186, 866–876 (2012). source

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Myocardial infarct triggers remodeling events that stiffen the ECM and change its chemical composition.

    “Contrarily, myocardial infarct is known to trigger remodeling events that stiffen the ECM and change its chemical composition; yet when mesenchymal stem cells are seeded on infarcted tissue, the cells secrete higher levels of pro-survival and immunomodulatory growth factors120.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [120] Sullivan, K. E., Quinn, K. P., Tang, K. M., Georgakoudi, I. & Black, L. D. Extracellular matrix remodeling following myocardial infarction influences the therapeutic potential of mesenchymal stem cells. Stem Cell Res. Ther. 5, 15 (2014). source

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  • May combine two claims.

    Premisecitation

    Not all decellularization protocols are equally effective at removing cells or other immunogenic species, which can cause varying host immune responses and failure of implants in clinical trials.

    “A related difficulty is that not all decellularization protocols are equally effective at removing cells or other immunogenic species, which can cause varying host immune responses and failure of implants in clinical trials122.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [122] Keane, T. J., Londono, R., Turner, N. J. & Badylak, S. F. Consequences of ineffective decellularization of biologic scaffolds on the host response. Biomaterials 33, 1771–1781 (2012). source

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  • May combine two claims.

    Premisecitation

    Collagen- and alginate-based materials have been approved by the FDA for a wide variety of applications, which allows for rapid clinical translation.

    “Collagen- and alginate-based materials have been approved by the FDA for a wide variety of applications117, which allows for rapid clinical translation.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [117] Matarasso, S. L. The use of injectable collagens for aesthetic rejuvenation. Semin. Cutan. Med. Surg. 25, 151–157 (2006). source

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    Premisecitation

    Organoid types grown in alginate include human lung, human brain, murine intestinal, human intestinal, human pancreatic, and human and murine vascular.

    “Organoid types grown in alginate include human lung99,100, human brain101, murine intestinal102, human intestinal102,103, human pancreatic104, and human and murine vascular105.”
    Quote in the paperNot a substantial claim0 of 7 sources checked
    • cites [99] Wilkinson, D. C. et al. Development of a three-dimensional bioengineering technology to generate lung tissue for personalized disease modeling. Stem Cells Transl. Med. 6, 622–633 (2017). source

      Not checked in the free run.

    • cites [100] Wilkinson, D. C. et al. Development of a three-dimensional bioengineering technology to generate lung tissue for personalized disease modeling. Curr. Protoc. Stem Cell Biol. 46, e56 (2018). source

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    • cites [101] Zhu, Y. J. et al. A hollow fiber system for simple generation of human brain organoids. Integr. Biol. 9, 774–781 (2017). source

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    • cites [102] Lu, Y.-C. et al. Scalable production and cryostorage of organoids using core-shell decoupled hydrogel capsules. Adv. Biosyst. 1, 1700165 (2017). source

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    • cites [103] Capeling, M. M. et al. Nonadhesive alginate hydrogels support growth of pluripotent stem cell-derived intestinal organoids. Stem Cell Rep. 12, 381–394 (2019). source

      Not checked in the free run.

    • cites [104] Liu, H. T. et al. A droplet microfluidic system to fabricate hybrid capsules enabling stem cell organoid engineering. Adv. Sci. 7, 9 (2020).

      Not checked in the free run.

    • cites [105] Rossen, N. S. et al. Injectable therapeutic organoids using sacrificial hydrogels. iScience 23, 101052 (2020). source

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  • May combine two claims.

    Premisecitation

    Optimal conditions (elastic moduli ranged from 2-4 kPa and scaffolds with MMP insensitivity) produce murine neural tube organoids that are more homogenous in colony size and morphology, as well as more polarized, than those grown in Matrigel.

    “The optimal conditions (elastic moduli ranged from 2–4 kPa and scaffolds with MMP insensitivity) produce murine neural tube organoids that are more homogenous in colony size and morphology, as well as more polarized, than those grown in Matrigel.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [156] Ranga, A. et al. 3D niche microarrays for systems-level analyses of cell fate. Nat. Commun. 5, 10 (2014). source

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  • May combine two claims.

    Premisecitation

    Many relevant tissues are viscoelastic, with brain tissue in particular having a strong dissipative component (high loss modulus) in its response to stress and slight differences in viscoelastic properties between white matter and gray matter.

    “Many relevant tissues are viscoelastic, with brain tissue in particular not only having a strong dissipative component (i.e., high loss modulus) in its response to stress137 but also having slight differences in viscoelastic properties between white matter and gray matter138.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [137] Li, W., Shepherd, D. E. T. & Espino, D. M. Frequency dependent viscoelastic properties of porcine brain tissue. J. Mech. Behav. Biomed. Mater. 102, 103460 (2020). source

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    • cites [138] Budday, S., Sommer, G., Holzapfel, G. A., Steinmann, P. & Kuhl, E. Viscoelastic parameter identification of human brain tissue. J. Mech. Behav. Biomed. Mater. 74, 463–476 (2017). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Choi and coworkers reviewed the pore sizes typically used in making tissue-engineering scaffolds, ranging from 5-15 microns for fibroblasts to 200-400 microns for osteoblasts, and developed a method for creating an artificial kidney scaffold using microstereolithography.

    “Choi and coworkers reviewed the pore sizes typically used in making tissue-engineering scaffolds, ranging from 5–15 microns for fibroblasts to 200–400 microns for osteoblasts, and developed a method for creating an artificial kidney scaffold using microstereolithography136.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [136] Choi, J.-W. et al. Fabrication of 3D biocompatible/biodegradable micro-scaffolds using dynamic mask projection microstereolithography. J. Mater. Process. Technol. 209, 5494–5503 (2009). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Human lung organoids transplanted in mice could merge together to form airway structures, but only if the scaffold was able to degrade, which increased the material's pore size.

    “Dye and coworkers found that human lung organoids transplanted in mice could merge together to form airway structures. However, this was only possible if the scaffold was able to degrade, which increased the material’s pore size135.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [135] Dye, B. R. et al. Human lung organoids develop into adult airway-like structures directed by physico-chemical biomaterial properties. Biomaterials 234, 119757 (2020). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    A Matrigel culture system had a pore size smaller than 200 nm, or the resolution limit of their confocal microscope, but a fibrin-based material had a pore size closer to 4 microns; these materials had comparable elastic moduli and colony-forming efficiency.

    “Broguiere and coworkers found that a Matrigel culture system had a pore size smaller than 200 nm, or the resolution limit of their confocal microscope, but that a fibrin-based material had a pore size closer to 4 microns; these materials had comparable elastic moduli and colony-forming efficiency88.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [88] Broguiere, N. et al. Growth of epithelial organoids in a defined hydrogel. Adv. Mater. 30, 1801621 (2018). source

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  • May combine two claims.

    Premisecitation

    The ability to exert local control over chemical and mechanical properties allows researchers to duplicate the heterogeneity in stiffness and composition found in organs, generate interfaces between materials similar to those found in the ECM, and duplicate essential elements of material microstructure; each of these controls has implications for organ function and disease.

    “The ability to exert local control over chemical and mechanical properties allows researchers to duplicate the heterogeneity in stiffness and composition found in organs, generate interfaces between materials similar to those found in the ECM, and duplicate essential elements of material microstructure; each of these controls has implications for organ function and disease131,132.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [131] Malandrino, A., Mak, M., Kamm, R. D. & Moeendarbary, E. Complex mechanics of the heterogeneous extracellular matrix in cancer. Extrem. Mech. Lett. 21, 25–34 (2018). source

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    • cites [132] Zhu, J. R., Liang, L., Jiao, Y. & Liu, L. Y., Allianc, U. S.-C. P. S.-O. Enhanced invasion of metastatic cancer cells via extracellular matrix interface. PLoS ONE 10, 17 (2015).

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  • Classified as probably not a substantial claim.

    Premisecitation

    Ovadia and colleagues compared photo-crosslinked PEG-based gels that contained chemical cues such as the laminin-derived cell-binding sequences YIGSR and IKVAV, the fibronectin-derived sequences PHSRNG10RGDS and RGDS, and the vitronectin-derived sequence KKQRFRHRNRKG.

    “To promote iPSC differentiation into human neuronal progenitor cells, Ovadia and colleagues compared photo-crosslinked PEG-based gels that contained chemical cues such as the laminin-derived cell-binding sequences YIGSR and IKVAV, the fibronectin-derived sequences PHSRNG10RGDS and RGDS, and the vitronectin-derived sequence KKQRFRHRNRKG161.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [161] Ovadia, E. M., Colby, D. W. & Kloxin, A. M. Designing well-defined photopolymerized synthetic matrices for three-dimensional culture and differentiation of induced pluripotent stem cells. Biomater. Sci. 6, 1358–1370 (2018). source

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  • May combine two claims.

    Premisecitation

    The stiffness of synthetic hydrogels can be controlled and has an effect on organoid formation.

    “The stiffness of synthetic hydrogels can be controlled and has an effect on organoid formation.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [162] Gjorevski, N. et al. Designer matrices for intestinal stem cell and organoid culture. Nature 539, 560–56 (2016). source

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  • May combine two claims.

    Premisecitation

    Attachment of human iPSCs was successful in assemblies functionalized with collagen I and laminin-521 but not with fibronectin.

    “Attachment of human iPSCs was successful in assemblies functionalized with collagen I and laminin-521 but not with fibronectin.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [158] Ng, S. S. et al. Human iPS derived progenitors bioengineered into liver organoids using an inverted colloidal crystal poly (ethylene glycol) scaffold. Biomaterials 182, 299–311 (2018). source

      Not checked in the free run.

    • cites [159] Shirahama, H. et al. Fabrication of inverted colloidal crystal poly(ethylene glycol) scaffold: a three-dimensional cell culture platform for liver tissue engineering. J. Vis. Exp. https://doi.org/10.3791/54331 (2016). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Ranga and colleagues prepared PEG-based gels in 1536-well plates and studied murine ESCs expressing an Oct4-GFP reporter.

    “A striking demonstration of the utility of high-throughput approaches was provided by Ranga and colleagues, who prepared PEG-based gels in 1536-well plates and studied murine ESCs (mESCs) expressing an Oct4-GFP reporter.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [156] Ranga, A. et al. 3D niche microarrays for systems-level analyses of cell fate. Nat. Commun. 5, 10 (2014). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Basic human liver function was recapitulated by a PEG-based scaffold.

    “This result builds on previous work by the authors, in which basic human liver function was recapitulated by a PEG-based scaffold160.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [160] Ng, S. S. et al. Long-term culture of human liver tissue with advanced hepatic functions. JCI Insight 2, 11 (2017). source

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  • May combine two claims.

    Premisecitation

    Synthetic hydrogels can be functionalized with biologically active moieties that permit the growth and spread of cells; concentration and spacing of these cues can be changed independently.

    “Synthetic hydrogels can be functionalized with biologically active moieties that permit the growth and spread of cells146–151; concentration and spacing of these cues can be changed independently152–155.”
    Quote in the paperSubstantial claim0 of 10 sources checked
    • cites [146] Lutolf, M. P. & Hubbell, J. A. Synthetic biomaterials as instructive extracellular microenvironments for morphogenesis in tissue engineering. Nat. Biotechnol. 23, 47–55 (2005). source

      Not checked in the free run.

    • cites [147] Nguyen, K. T. & West, J. L. Photopolymerizable hydrogels for tissue engineering applications. Biomaterials 23, 4307–4314 (2002). source

      Not checked in the free run.

    • cites [148] Saha, K., Pollock, J. F., Schaffer, D. V. & Healy, K. E. Designing synthetic materials to control stem cell phenotype. Curr. Opin. Chem. Biol. 11, 381–387 (2007). source

      Not checked in the free run.

    • cites [149] Tibbitt, M. W. & Anseth, K. S. Dynamic microenvironments: the fourth dimension. Sci. Transl. Med. 4, 4 (2012). source

      Not checked in the free run.

    • cites [150] Lutolf, M. P. & Hubbell, J. A. Synthesis and physicochemical characterization of end-linked poly(ethylene glycol)-co-peptide hydrogels formed by Michael-type addition. Biomacromolecules 4, 713–722 (2003). source

      Not checked in the free run.

    • cites [151] Lutolf, M. R. et al. Repair of bone defects using synthetic mimetics of collagenous extracellular matrices. Nat. Biotechnol. 21, 513–518 (2003). source

      Not checked in the free run.

    • cites [152] Wylie, R. G. et al. Spatially controlled simultaneous patterning of multiple growth factors in three-dimensional hydrogels. Nat. Mater. 10, 799–806 (2011). source

      Not checked in the free run.

    • cites [153] DeForest, C. A. & Anseth, K. S. Photoreversible patterning of biomolecules within click-based hydrogels. Angew. Chem. Int. Ed. 51, 1816–1819 (2012). source

      Not checked in the free run.

    • cites [154] Mosiewicz, K. A. et al. In situ cell manipulation through enzymatic hydrogel photopatterning. Nat. Mater. 12, 1071–1077 (2013). source

      Not checked in the free run.

    • cites [155] DeForest, C. A. & Tirrell, D. A. A photoreversible protein-patterning approach for guiding stem cell fate in three-dimensional gels. Nat. Mater. 14, 523–531 (2015). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    There have been a number of studies showing that organoids can be grown on unmodified surfaces such as alginate, but this requires more research.

    “There have been a number of studies showing that organoids can be grown on unmodified surfaces such as alginate, but this requires more research103,105,110,175,183.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [103] Capeling, M. M. et al. Nonadhesive alginate hydrogels support growth of pluripotent stem cell-derived intestinal organoids. Stem Cell Rep. 12, 381–394 (2019). source

      Not checked in the free run.

    • cites [105] Rossen, N. S. et al. Injectable therapeutic organoids using sacrificial hydrogels. iScience 23, 101052 (2020). source

      Not checked in the free run.

    • cites [110] Fu, S. et al. Rheological evaluation of inter-grade and inter-batch variability of sodium alginate. AAPS PharmSciTech. 11, 1662–1674 (2010). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    A major advantage of using synthetic polymers for organoid culture is that they are amenable to systematic variation in structure and properties and can be used to explore the effects of mechanical and chemical cues on cellular fate.

    “A major advantage of using synthetic polymers for organoid culture is that they are amenable to systematic variation in structure and properties and can be used to explore the effects of mechanical and chemical cues on cellular fate178,179.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [178] Li, C. Y. et al. Micropatterned cell-cell interactions enable functional encapsulation of primary hepatocytes in hydrogel microtissues. Tissue Eng. Part A 20, 2200–2212 (2014). source

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    • cites [179] Lee, H. J. et al. Elasticity-based development of functionally enhanced multicellular 3D liver encapsulated in hybrid hydrogel. Acta Biomater. 64, 67–79 (2017). source

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  • May combine two claims.

    Premisecitation

    Synthetic hydrogels may degrade into cytotoxic by-products or require cytotoxic initiators, limiting the types of polymers that can be used in cell culture.

    “Further, synthetic hydrogels may degrade into cytotoxic by-products184 or require cytotoxic initiators185, limiting the types of polymers that can be used in cell culture186.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [184] Vihola, H., Laukkanen, A., Valtola, L., Tenhu, H. & Hirvonen, J. Cytotoxicity of thermosensitive polymers poly(N-isopropylacrylamide), poly(N-vinylcaprolactam) and amphiphilically modified poly(N-vinylcaprolactam). Biomaterials 26, 3055–3064 (2005). source

      Not checked in the free run.

    • cites [185] Liu, V. A. & Bhatia, S. N. Three-dimensional photopatterning of hydrogels containing living Ccells. Biomed. Microdevices 4, 257–266 (2002). source

      Not checked in the free run.

    • cites [186] Kharkar, P. M., Kiick, K. L. & Kloxin, A. M. Designing degradable hydrogels for orthogonal control of cell microenvironments. Chem. Soc. Rev. 42, 7335–7372 (2013). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    A number of groups were able to generate spheroids in chip-based devices, but the spheroids lack spatial complexity and cell types compared to fully-developed organoids.

    “A number of groups were able to generate spheroids in chip-based devices171–173, but the spheroids lack spatial complexity and cell types compared to fully-developed organoids.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [171] Patra, B. et al. A microfluidic device for uniform-sized cell spheroids formation, culture, harvesting and flow cytometry analysis. Biomicrofluidics 7, 054114 (2013). source

      Not checked in the free run.

    • cites [172] Lee, G. H. et al. Networked concave microwell arrays for constructing 3D cell spheroids. Biofabrication 10, 015001 (2017). source

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    • cites [173] Yoon, S.-J. et al. Reliability of human cortical organoid generation. Nat. Methods 16, 75–78 (2019). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Compared to cells grown in Matrigel, beta-like cells grown in Amikagel produced higher levels of functional beta-cell markers PDX1 and NKX6.1 and were more responsive to a glucose challenge.

    “Compared to cells grown in Matrigel, beta-like cells grown in Amikagel produced higher levels of functional beta-cell markers PDX1 and NKX6.1 and were more responsive to a glucose challenge.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [175] Candiello, J. et al. 3D heterogeneous islet organoid generation from human embryonic stem cells using a novel engineered hydrogel platform. Biomaterials 177, 27–39 (2018). source

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  • May combine two claims.

    Premisecitation

    The concentration of laminin-derived IKVAV, with 300 μM being the optimal concentration, was critical to neural organoid survival; however, this concentration did not enhance neuronal differentiation.

    “Lam and colleagues found that the concentration of laminin-derived IKVAV, with 300 μM being the optimal concentration, was critical to neural organoid survival; however, this concentration did not enhance neuronal differentiation115.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [115] Lam, J., Carmichael, S. T., Lowry, W. E. & Segura, T. Hydrogel design of experiments methodology to optimize hydrogel for iPSC-NPC culture. Adv. Healthc. Mater. 4, 534–539 (2015). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Down syndrome patient-derived iPSCs differentiated in the softer gel showed no discernable neurite outgrowth, suggesting a block in the maturation of the differentiated neurons.

    “However, Down syndrome patient-derived iPSCs that were differentiated in the softer gel showed no discernable neurite outgrowth, suggesting a block in the maturation of the differentiated neurons.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [114] Wu, S. H., Xu, R. J., Duan, B. & Jiang, P. Three-dimensional hyaluronic acid hydrogel-based models for in vitro human iPSC-derived NPC culture and differentiation. J. Mat. Chem. B 5, 3870–3878 (2017). source

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  • May combine two claims.

    Premisecitation

    Larger islets have been known to form necrotic centers because of a lack of oxygen and nutrient diffusion; other studies have found that islets best maintain cellular identity and function when they have a size of ca. 100-150 microns.

    “Larger islets have been known to form necrotic centers because of a lack of oxygen and nutrient diffusion; other studies have found that islets best maintain cellular identity and function when they have a size of ca. 100–150 microns177.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [177] Hilderink, J. et al. Controlled aggregation of primary human pancreatic islet cells leads to glucose-responsive pseudoislets comparable to native islets. J. Cell. Mol. Med. 19, 1836–1846 (2015). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The smallest cell aggregates reported by the authors were ca. 200 microns in diameter; the typical human islet has a diameter of ca. 130 microns.

    “The smallest cell aggregates reported by the authors were ca. 200 microns in diameter; the typical human islet has a diameter of ca. 130 microns176.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [175] Candiello, J. et al. 3D heterogeneous islet organoid generation from human embryonic stem cells using a novel engineered hydrogel platform. Biomaterials 177, 27–39 (2018). source

      Not checked in the free run.

    • cites [176] Rorsman, P. & Braun, M. in Annual Review of Physiology Vol. 75 (ed. Julius, D) (Annual Reviews, 2013). source

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  • May combine two claims.

    Premisecitation

    Synthetic hydrogels used as medical implants can trigger foreign body reactions; similar effects may be seen in immunogen-containing organoids.

    “Finally, synthetic hydrogels used as medical implants can trigger foreign body reactions188; similar effects may be seen in immunogen-containing organoids.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [188] Anderson, J. M., Rodriguez, A. & Chang, D. T. Foreign body reaction to biomaterials. Semin. Immunol. 20, 86–100 (2008). source

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    Premisecitation

    Functionalizing hyaluronic acid with heparin affects neuronal patterning; the addition of heparin favored differentiation of human progenitors into neurons with a hindbrain fate, whereas non-functionalized hyaluronic acid favored a forebrain fate.

    “Bejoy and colleagues showed that functionalizing hyaluronic acid with heparin affects neuronal patterning; the addition of heparin favored differentiation of human progenitors into neurons with a hindbrain fate, whereas non-functionalized hyaluronic acid favored a forebrain fate.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [116] Bejoy, J. et al. Differential effects of heparin and hyaluronic acid on neural patterning of human induced pluripotent stem cells. ACS Biomater. Sci. Eng. 4, 4354–4366 (2018). source

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  • May combine two claims.

    Premisecitation

    Neural organoids present special challenges including a lack of reproducibility, batch-to-batch variation in transcriptional profiles, and susceptibility to small microenvironmental changes that may have a considerable effect on organoid fate.

    “Neural organoids present special challenges including a lack of reproducibility, batch-to-batch variation in transcriptional profiles, and susceptibility to small microenvironmental changes that may have a considerable effect on organoid fate165.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [165] Di Lullo, E. & Kriegstein, A. R. The use of brain organoids to investigate neural development and disease. Nat. Rev. Neurosci. 18, 573 (2017). source

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  • May combine two claims.

    Premisecitation

    The stiffness of the hybrid hyaluronic acid material is relevant to cell fate determination; lower elastic moduli, ca. 300 Pa, led to forebrain development, whereas higher elastic moduli, ca. 1000 Pa, led to hindbrain development.

    “The authors also established that the stiffness of this hybrid material is relevant to cell fate determination; lower elastic moduli, ca. 300 Pa, led to forebrain development, whereas higher elastic moduli, ca. 1000 Pa, led to hindbrain development116.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [116] Bejoy, J. et al. Differential effects of heparin and hyaluronic acid on neural patterning of human induced pluripotent stem cells. ACS Biomater. Sci. Eng. 4, 4354–4366 (2018). source

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  • May combine two claims.

    Premisecitation

    The differentiation of both normal and Down syndrome iPSCs into neurons was dependent on matrix stiffness; cells could be grown at a softer elastic modulus of ca. 500 Pa but not ca. 1500 Pa.

    “The authors found that the differentiation of both normal and Down syndrome iPSCs into neurons was dependent on matrix stiffness; cells could be grown at a softer elastic modulus of ca. 500 Pa but not ca. 1500 Pa, as indicated by higher expression of β-2 tubulin and microtubule-associated protein 2.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [114] Wu, S. H., Xu, R. J., Duan, B. & Jiang, P. Three-dimensional hyaluronic acid hydrogel-based models for in vitro human iPSC-derived NPC culture and differentiation. J. Mat. Chem. B 5, 3870–3878 (2017). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Inhibition of MMP activity reduced organoid-forming efficiency in the stiffer engineered hydrogel matrices, suggesting that secretion of degradative enzymes in adult intestinal organoids may be a response to overly stiff conditions.

    “Inhibition of MMP activity reduced organoid-forming efficiency in the stiffer engineered hydrogel matrices, suggesting that secretion of degradative enzymes in adult intestinal organoids may be a response to overly stiff conditions191.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [191] DiMarco, R. L., Dewi, R. E., Bernal, G., Kuoc, C. & Heilshorn, S. C. Protein-engineered scaffolds for in vitro 3D culture of primary adult intestinal organoids. Biomater. Sci. 3, 1376–1385 (2015). source

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  • May combine two claims.

    Premisecitation

    When Matrigel was added, endocrine and acinar cell development was inhibited while ductal cell formation was promoted, demonstrating the importance of the ECM microenvironment in pancreatic organoid differentiation.

    “A follow-up study established that when Matrigel was added, endocrine and acinar cell development was inhibited while ductal cell formation was promoted193, demonstrating the importance of the ECM microenvironment in pancreatic organoid differentiation.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [193] Ghazalli, N. et al. Postnatal pancreas of mice contains tripotent progenitors capable of giving rise to duct, acinar, and endocrine cells in vitro. Stem Cells Dev. 24, 1995–2008 (2015). source

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    Premisecitation

    Recombinant proteins are molecularly well-defined and can be tuned independently for stiffness, viscoelastic behavior, and chemical functionality.

    “Recombinant proteins are molecularly well-defined and can be tuned independently for stiffness, viscoelastic behavior, and chemical functionality203–205.”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [203] Madl, C. M., Katz, L. M. & Heilshorn, S. C. Bio-orthogonally crosslinked, engineered protein hydrogels with tunable mechanics and biochemistry for cell encapsulation. Adv. Funct. Mater. 26, 3612–3620 (2016). source

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    • cites [204] Liu, X. et al. Versatile engineered protein hydrogels enabling decoupled mechanical and biochemical tuning for cell adhesion and neurite growth. ACS Appl. Nano Mater. 1, 1579–1585 (2018). source

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    • cites [205] Dooling, L. J. & Tirrell, D. A. Engineering the dynamic properties of protein networks through sequence variation. ACS Cent. Sci. 2, 812–819 (2016). source

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    The programmability of recombinant proteins has prompted increasing interest in the design of protein-based hydrogels as matrices for organoid culture.

    “The programmability of recombinant proteins has prompted increasing interest in the design of protein-based hydrogels as matrices for organoid culture.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    After 2 weeks, endocrine-acinar organoids were observed, demonstrating that aECM-lam was capable of inducing differentiation of ductal progenitor cells into endocrine and acinar lineages.

    “After 2 weeks, endocrine-acinar organoids were observed, demonstrating that aECM-lam was capable of inducing differentiation of ductal progenitor cells into endocrine and acinar lineages192.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [192] Jin, L. et al. Colony-forming cells in the adult mouse pancreas are expandable in Matrigel and form endocrine/acinar colonies in laminin hydrogel. Proc. Natl Acad. Sci. USA 110, 3907–3912 (2013). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S2 (checkable), S4 (based). May combine two claims.

    Interpretationnone given

    Although several Matrigel-free techniques have been developed, they have been used in a narrow range of target tissues; expanding the number of tissue types will increase the acceptance of these alternative techniques.

    “Although several Matrigel-free techniques have been developed, they have been used in a narrow range of target tissues; expanding the number of tissue types will increase the acceptance of these alternative techniques.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Similar work has shown promise in stem cell differentiation and neural regeneration following spinal injury in vivo, further demonstrating the utility of peptide-based materials in cell culture.

    “Similar work has shown promise in stem cell differentiation and neural regeneration following spinal injury in vivo200–202, further demonstrating the utility of peptide-based materials in cell culture.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [200] Stephanopoulos, N. et al. Bioactive DNA-peptide nanotubes enhance the differentiation of neural stem cells into neurons. Nano Lett. 15, 603–609 (2015). source

      Not checked in the free run.

    • cites [201] Lee, S. S. et al. Gel scaffolds of BMP-2-binding peptide amphiphile nanofibers for spinal arthrodesis. Adv. Health. Mater. 4, 131–141 (2015). source

      Not checked in the free run.

    • cites [202] Berns, E. J. et al. Aligned neurite outgrowth and directed cell migration in self-assembled monodomain gels. Biomaterials 35, 185–195 (2014). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Among the elastic moduli studied (700, 3000, and 4000 Pa), the softest material favored the proliferation of embryoid bodies that contain mesodermal progenitor cells and promoted rapid cardiomyocyte differentiation.

    “Among the elastic moduli studied (700, 3000, and 4000 Pa), the softest material favored the proliferation of embryoid bodies that contain mesodermal progenitor cells and promoted rapid cardiomyocyte differentiation (Fig. 5).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [190] Chung, C., Pruitt, B. L. & Heilshorn, S. C. Spontaneous cardiomyocyte differentiation of mouse embryoid bodies regulated by hydrogel crosslink density. Biomater. Sci. 1, 1082–1090 (2013). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Pagliuca and colleagues kept human embryonic stem cells suspended in liquid culture at 70 rpm, added specific growth factors to encourage differentiation, and found that the resulting beta-like cells behaved similarly to mature beta cells.

    “For instance, Pagliuca and colleagues kept human embryonic stem cells suspended in liquid culture at 70 rpm, added specific growth factors to encourage differentiation, and found that the resulting beta-like cells behaved similarly to mature beta cells220.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [220] Pagliuca, FeliciaW. et al. Generation of functional human pancreatic β cells in vitro. Cell 159, 428–439 (2014). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    Control over the mechanical environment in such a system could be exerted by changing the speed of agitation.

    “Control over the mechanical environment in such a system could be exerted by changing the speed of agitation.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Display of BDNF on the peptide amphiphile is necessary for this effect to be observed.

    “Display of BDNF on the peptide amphiphile is necessary for this effect to be observed199.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [199] Edelbrock, A. N. et al. Supramolecular nanostructure activates TrkB receptor signaling of neuronal cells by mimicking brain-derived neurotrophic factor. Nano Lett. 18, 6237–6247 (2018). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Chung and colleagues generated a hydrogel using an elastin-like polypeptide matrix containing a fibronectin-derived RGD cell-binding domain with THPC as an amine-reactive crosslinker; this material transiently inhibited contractility of murine ESC-derived cardiomyocytes and enhanced survival of dorsal root ganglia cells from chick embryos.

    “Chung and colleagues generated a hydrogel using an elastin-like polypeptide matrix containing a fibronectin-derived RGD cell-binding domain with tetrakis(hydroxymethyl)phosphonium chloride (THPC) as an amine-reactive crosslinker; this material transiently inhibited contractility of murine ESC-derived cardiomyocytes and enhanced survival of dorsal root ganglia cells from chick embryos189.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [189] Chung, C., Lampe, K. J. & Heilshorn, S. C. Tetrakis(hydroxymethyl) phosphonium chloride as a covalent cross-linking agent for cell encapsulation within protein-based hydrogels. Biomacromolecules 13, 3912–3916 (2012). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Protein-based hydrogels can be outfitted with a broad range of chemical functionalities by introducing noncanonical amino acids; they can also be readily tailored to a wide variety of biomedical contexts and made thermally responsive.

    “Protein-based hydrogels can be outfitted with a broad range of chemical functionalities by introducing noncanonical amino acids208,209; they can also be readily tailored to a wide variety of biomedical contexts210,211 and made thermally responsive212,213.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [208] Link, A. J., Mock, M. L. & Tirrell, D. A. Non-canonical amino acids in protein engineering. Curr. Opin. Biotechnol. 14, 603–609 (2003). source

      Not checked in the free run.

    • cites [209] Connor, R. E. & Tirrell, D. A. Non‐canonical amino acids in protein polymer design. Polym. Rev. 47, 9–28 (2007). source

      Not checked in the free run.

    • cites [210] Langer, R. & Tirrell, D. A. Designing materials for biology and medicine. Nature 428, 487–492 (2004). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The peptides contain brain-derived neurotrophic factor (BDNF), which enables the formation of mature neurons via activation of the TrkB pathway.

    “The peptides contain brain-derived neurotrophic factor (BDNF), which enables the formation of mature neurons via activation of the TrkB pathway.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [199] Edelbrock, A. N. et al. Supramolecular nanostructure activates TrkB receptor signaling of neuronal cells by mimicking brain-derived neurotrophic factor. Nano Lett. 18, 6237–6247 (2018). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    HYDROSAP peptide 3D hydrogels with elastic moduli of ~800 Pa (similar to the stiffness of human brain tissue) were used to culture human fetal neural stem cells, which were able to differentiate into various lineages including astrocytes, oligodendrocytes, and neurons.

    “The authors used HYDROSAP peptide 3D hydrogels with elastic moduli of ~800 Pa (similar to the stiffness of human brain tissue) to culture human fetal neural stem cells198, which were able to differentiate into various lineages including astrocytes, oligodendrocytes, and neurons.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [198] Marchini, A. et al. Multifunctionalized hydrogels foster hNSC maturation in 3D cultures and neural regeneration in spinal cord injuries. Proc. Natl Acad. Sci. USA 116, 7483–7492 (2019). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The corresponding 2D culture did not show this activation and localization, suggesting that the 3D organoid culture of neurons is critical for modeling Alzheimer's disease.

    “In contrast, the corresponding 2D culture did not show this activation and localization, suggesting that the 3D organoid culture of neurons is critical for modeling Alzheimer’s disease196.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [196] Zhang, D. W. et al. A 3D Alzheimer’s disease culture model and the induction of P21-activated kinase mediated sensing in iPSC derived neurons. Biomaterials 35, 1420–1428 (2014). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    For these reasons, it may be advantageous to engineer recombinant protein gels.

    “For these reasons, it may be advantageous to engineer recombinant protein gels.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    Collectively, these studies demonstrate the utility of aECM-lam in promoting endocrine and acinar cell differentiation in pancreatic organoid culture and identifying the responsible progenitor population.

    “Collectively, these studies demonstrate the utility of aECM-lam in promoting endocrine and acinar cell differentiation in pancreatic organoid culture and identifying the responsible progenitor population.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Inhibition of MMP secretion was deleterious to proliferation and differentiation, suggesting that remodeling of the matrix is essential in cardiomyocyte differentiation.

    “Inhibition of MMP secretion was deleterious to proliferation and differentiation, suggesting that remodeling of the matrix is essential in cardiomyocyte differentiation190.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [190] Chung, C., Pruitt, B. L. & Heilshorn, S. C. Spontaneous cardiomyocyte differentiation of mouse embryoid bodies regulated by hydrogel crosslink density. Biomater. Sci. 1, 1082–1090 (2013). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S2 (checkable). May combine two claims.

    Interpretationreasoning

    Using the methods discussed above, we anticipate a gradual shift away from the use of Matrigel in organoid culture and towards methods that enable exact control of the cell's mechanical and chemical environments with a more precise definition.

    “Using the methods discussed above, we anticipate a gradual shift away from the use of Matrigel in organoid culture and towards methods that enable exact control of the cell’s mechanical and chemical environments with a more precise definition.”
    Quote in the paperNot a substantial claim
77 of 77

  • The paper relies on this without support.

    The quantity of ECM available for study is limited by the availability of donor animals or humans.

    “Most importantly, the quantity of ECM that is available for study is limited by the availability of donor animals or humans, and the quality of ECM can be affected by the health of a donor.”

  • The paper relies on this without support.

    The quality of ECM can be affected by the health of a donor.

    “Most importantly, the quantity of ECM that is available for study is limited by the availability of donor animals or humans, and the quality of ECM can be affected by the health of a donor.”

  • The paper relies on this without support.

    Even with healthy donor tissue, batch-to-batch variability remains.

    “Even with healthy donor tissue, batch-to-batch variability remains.”

  • The paper relies on this without support.

    The physical properties of decellularized ECM are difficult to control or modify.

    “The physical properties of decellularized ECM are difficult to control or modify, which limits the experiments that can be conducted.”

  • The paper relies on this without support.

    Decellularized ECM is chemically undefined; the factors driving differentiation are often unknown.

    “Decellularized ECM is also chemically undefined; the factors driving differentiation are often unknown.”

  • The paper relies on this without support.

    Biomedical-grade collagen can be harvested on an industrial scale from cows and pigs.

    “Collagen-based culture methods are not limited by donor tissue availability; biomedical-grade collagen can be harvested on an industrial scale from cows and pigs.”

  • The paper relies on this without support.

    It is difficult to modify the mechanical properties of collagen-based culture systems without altering chemical concentrations.

    “Furthermore, it is difficult to modify the mechanical properties of these culture systems without altering chemical concentrations.”

  • The paper relies on this without support.

    The human pancreas has a higher lipid content than animal models.

    “The human pancreas presents a challenge in decellularization as it has a higher lipid content than animal models.”

  • The authors state this as an assumption.

    A matrix is required to culture organoids.

    “This review has proceeded with the assumption that a matrix is required to culture organoids, but matrix-free culture systems have also been developed.”

  • The paper relies on this without support.

    Many synthetic materials, including PEG and PLGA, have been approved by the FDA for use in human therapeutics.

    “Moreover, many such materials, including PEG and PLGA, have been approved by the FDA for use in human therapeutics.”

  • The paper relies on this without support.

    The backbone materials of synthetic hydrogels are cheap and can be produced on an industrial scale.

    “While the backbone materials of synthetic hydrogels are cheap and can be produced on an industrial scale, functionalization of these materials with precisely-placed, custom-made peptides significantly increases cost and requires expertise in materials science, making these materials less attractive to cell biology labs.”

  • The paper relies on this without support.

    Functionalization of synthetic hydrogels with precisely-placed, custom-made peptides significantly increases cost and requires expertise in materials science, making these materials less attractive to cell biology labs.

    “While the backbone materials of synthetic hydrogels are cheap and can be produced on an industrial scale, functionalization of these materials with precisely-placed, custom-made peptides significantly increases cost and requires expertise in materials science, making these materials less attractive to cell biology labs.”

  • The paper relies on this without support.

    Not all proteins can be recombinantly expressed and ensuring re-folding and functionality of these proteins can be challenging.

    “First, not all proteins can be recombinantly expressed and ensuring re-folding and functionality of these proteins can be challenging.”
13 of 13

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Formation of necrotic cores was previously observed in other large organoid systems.

    “The formation of necrotic cores was previously observed in other large organoid systems [19].”

    From Efficient Generation of Skin Organoids from Pluripotent Cells via Defined Extracellular Matrix Cues and Morphogen Gradients in a Spindle‐Shaped Microfluidic Device (2024) · cites this paper as [19]

    In “Synthetic hydrogels in action: Modeling difficult tissues such as the brain and pancreas” (page unavailable), the review says larger islets are known to form necrotic centers because oxygen and nutrients cannot diffuse sufficiently. It raises this as a concern while discussing the size of islet-organoid aggregates, but does not say necrotic cores were observed in those organoids or in other large organoid systems. (LLM, conf=0.82)

    Experimental — accuracy not yet measured

  • Matrigel has an ill-defined chemistry and composition, and major lot-to-lot variation, and thus offers poor control over ECM composition.

    “Although Matrigel provides important biochemical cues, it has an ill-defined chemistry and composition, and major lot-to-lot variation [18,19], and thus offers a poor control over ECM composition [20].”

    From Efficient Generation of Skin Organoids from Pluripotent Cells via Defined Extracellular Matrix Cues and Morphogen Gradients in a Spindle‐Shaped Microfluidic Device (2024) · cites this paper as [19]

  • Pooling different cells and/or organoids for bulk analysis can lead to inaccurate results.

    “Pooling together different cells and/or organoids for bulk analysis can lead to inaccurate results3,70,100,204,207,208.”

    From Organoids (2022) · cites this paper as [207]

    The section on neural organoids notes batch-to-batch variation in transcriptional profiles, but it does not say that pooling cells or organoids for bulk analysis produces inaccurate results. Searches for the claim’s wording and for bulk analysis masking heterogeneity found no passage addressing that point. (LLM, conf=0.70)

    Experimental — accuracy not yet measured

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Conflicting cell source for the intestinal organoid experiment

    Minor

    The figure caption says the experiment differentiated induced pluripotent cells, while the main text describes the same study as culturing Lgr5+ progenitor cells derived from intestinal crypts. These are different starting cell populations.

1 of 1

The citation lists haven’t been fetched yet

References 222 · Cited by 409

Authors
Kozlowski, M. T., Crook, C. J., & Ku, H. T.
Affiliations
  • DEVCOM Army Research Laboratory (US)
  • City Of Hope National Medical Center (US)
Corresponding author
Kozlowski, Mark T.
ORCID
Venue
Communications Biology
Publisher
Springer Science and Business Media LLC
Published
2021-12-10
Volume
4
Issue
1
Pages
1387-1387
ISSN
2399-3642 (ISSN-L)
DOI
10.1038/s42003-021-02910-8
PMC
PMC8664924
OpenAlex
W4200071554
Semantic Scholar
f95642963441b865a84f05668c7ac21bb8e07871
Cited by
409
References
222
Citations by year
2026: 78 · 2025: 111 · 2024: 103 · 2023: 74 · 2022: 43
FWCI
13.37
Type
journal article
Language
en
Open access
Licence
Locations
  • Communications Biology (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • U.S. Department of Defense (NDSEG)
  • U.S. Department of Health & Human Services | National Institutes of Health (R01DK099734)
Topics
  • Health Sciences › Medicine › Surgery › Tissue Engineering and Regenerative Medicine
  • Physical Sciences › Engineering › Biomedical Engineering › 3D Printing in Biomedical Research
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Medicine › Hydrogels: synthesis, properties, applications
Keywords
organoids, decellularized extracellular matrix, synthetic hydrogels, stem cells, organogenesis
MeSH terms
Decellularized Extracellular Matrix, Animals, Biocompatible Materials, Collagen, Drug Combinations, Humans, Laminin, Organoids, Proteoglycans, Hydrogels, Tissue Culture Techniques, Mice

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-07.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-07.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

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