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Cited by 463D Printing in Biomedical ResearchTissue Engineering and Regenerative MedicineHydrogels: synthesis, properties, applications

3D bioprinting of multi-material decellularized liver matrix hydrogel at physiological temperatures

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Khati, Vamakshi, Ramachandraiah, Harisha, Pati, Falguni, Svahn, Helene A., Gaudenzi, Giulia, Russom, Aman·2022·Biosensors
DOI 10.3390/bios12070521PMC PMC9313433
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Abstract

Bioprinting is an acclaimed technique that allows the scaling of 3D architectures in an organized pattern but suffers from a scarcity of appropriate bioinks. Decellularized extracellular matrix (dECM) from xenogeneic species has garnered support as a biomaterial to promote tissue-specific regeneration and repair. The prospect of developing dECM-based 3D artificial tissue is impeded by its inherent low mechanical properties. In recent years, 3D bioprinting of dECM-based bioinks modified with additional scaffolds has advanced the development of load-bearing constructs. However, previous attempts using dECM were limited to low-temperature bioprinting, which is not favorable for a longer print duration with cells. Here, we report the development of a multi-material decellularized liver matrix (dLM) bioink reinforced with gelatin and polyethylene glycol to improve rheology, extrudability, and mechanical stability. This shear-thinning bioink facilitated extrusion-based bioprinting at 37 °C with HepG2 cells into a 3D grid structure with a further enhancement for long-term applications by enzymatic crosslinking with mushroom tyrosinase. The heavily crosslinked structure showed a 16-fold increase in viscosity (2.73 Pa s−1) and a 32-fold increase in storage modulus from the non-crosslinked dLM while retaining high cell viability (85–93%) and liver-specific functions. Our results show that the cytocompatible crosslinking of dLM bioink at physiological temperatures has promising applications for extended 3D-printing procedures.

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  • GAG concentrations in dLECM hydrogels were between 30 and 80 μg/mg.

    “Collagen concentrations tended to be in the range between 40 and 200 μg/mg, whereas GAGs were found at concentrations between 30 and 80 μg/mg.”

    From From scaffold to function: A systematic review on dLECM-based hydrogels for liver tissue engineering — Fabrication, properties, and translational applications (2026) · cites this paper as [20]

    Section 3.1 (page unavailable) reports 2.03 ± 0.17 μg/mg of GAGs remaining in the decellularized liver tissue, far below the claimed 30–80 μg/mg. The paper reports this for tissue rather than separately measuring GAG concentration in the formulated hydrogel. (LLM, conf=0.87)

    Checked by a reasoning model — may be wrong.

    Experimental — accuracy not yet measured

  • Collagen concentrations in dLECM hydrogels tended to be between 40 and 200 μg/mg.

    “Collagen concentrations tended to be in the range between 40 and 200 μg/mg, whereas GAGs were found at concentrations between 30 and 80 μg/mg.”

    From From scaffold to function: A systematic review on dLECM-based hydrogels for liver tissue engineering — Fabrication, properties, and translational applications (2026) · cites this paper as [20]

    Section 3.1 (page unavailable) reports 29.05 ± 0.52 μg of collagen per mg of decellularized liver tissue, below the claimed 40–200 μg/mg range. It also reports 2.03 ± 0.17 μg/mg of GAGs, rather than the 30–80 μg/mg stated in the citing sentence. (LLM, conf=0.89)

    Checked by a reasoning model — may be wrong.

    Experimental — accuracy not yet measured

  • Collagen and GAG levels tended to change with the extent of decellularization.

    “These levels tended to change with the extent of the decellularization process [19,20].”

    From From scaffold to function: A systematic review on dLECM-based hydrogels for liver tissue engineering — Fabrication, properties, and translational applications (2026) · cites this paper as [20]

    Section 3.1 reports that GAG levels fell and measured collagen content rose after decellularization, compared with native liver. It compares only before and after, not different extents of decellularization; it also cautions that the collagen comparison is ambiguous because of how the assay is normalized. (LLM, conf=0.82)

    Experimental — accuracy not yet measured

  • dLECM can be developed into bioinks with tunable rheometric properties, allowing printing of structurally intricate, functionally active, and potentially implantable liver constructs.

    “Exemplar studies by Khati et al. (2022), Tabatabaei Rezaei et al. (2025), and Kim et al. (2023) have shown that dLECM can be developed into bioinks with tunable rheometric properties, allowing the printing of structurally intricate, functionally active, and potentially implantable liver constructs [20,25,58].”

    From From scaffold to function: A systematic review on dLECM-based hydrogels for liver tissue engineering — Fabrication, properties, and translational applications (2026) · cites this paper as [20]

    The Introduction and Results and Discussions (§§3.2–3.4; page not provided) support a liver-matrix bioink with adjustable rheological properties, printed as a four-layer grid with HepG2 cells showing liver-specific activity. The paper describes complex liver-like architectures and in vivo tissue regeneration as future possibilities; it does not demonstrate a structurally intricate or implantable liver construct. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

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Sorted by citations

Authors
Khati, V., Ramachandraiah, H., Pati, F., Svahn, H. A., Gaudenzi, G., & Russom, A.
Affiliations
  • Science for Life Laboratory (SE)
  • Biopromic AB, 17165 Solna, Sweden
  • Indian Institute of Technology Hyderabad (IN)
Corresponding author
Russom, Aman
ORCID
Venue
Biosensors
Publisher
MDPI AG
Published
2022-07-13
Volume
12
Issue
7
Pages
521
ISSN
2079-6374 (ISSN-L)
DOI
10.3390/bios12070521
PMC
PMC9313433
OpenAlex
W4285394071
Cited by
46
References
2
Citations by year
2026: 6 · 2025: 8 · 2024: 16 · 2023: 14 · 2022: 2
FWCI
2.91
Type
journal article
Language
en
Open access
Licence
Locations
  • Biosensors (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Research Archive of Indian Institute of Technology Hyderabad (Indian Institute of Technology Hyderabad) (acceptedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • Swedish Research Council (2015-05378, 610472, 2019-05170)
  • European Commission (2015-05378, 610472, 2019-05170)
Topics
  • Physical Sciences › Engineering › Biomedical Engineering › 3D Printing in Biomedical Research
  • Health Sciences › Medicine › Surgery › Tissue Engineering and Regenerative Medicine
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Medicine › Hydrogels: synthesis, properties, applications
Keywords
3D bioprinting, gelatin, polyethylene glycol, enzymatic crosslinking, tyrosinase, HepG2 cells, shear-thinning rheology, extrusion-based bioprinting, physiological temperature, mechanical properties, liver tissue engineering, cytocompatibility
MeSH terms
Extracellular Matrix, Liver, Temperature, Hydrogels, Tissue Engineering, Tissue Scaffolds, Bioprinting

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