Material stiffness influences the polarization state, function and migration mode of macrophages
Abstract
Biomaterial implantation is followed by an inflammatory cascade dominated by macrophages, which determine implant acceptance or rejection through pro- and anti-inflammatory polarization states (Anderson et al., 2008; Brown and Badylak, 2013). It is known that chemical signals such as bacterial endotoxins and cytokines (IL4) can direct macrophage polarization (Mantovani et al., 2004); however, recent evidence implicates biophysical cues in this process (McWhorter et al., 2015; Patel et al., 2012). Here we report that THP-1 derived macrophages cultured on collagen-coated polyacrylamide gels of varying stiffness adapt their polarization state, functional roles and migration mode according to the stiffness of the underlying substrate. Through gene expression and protein secretion analysis, we show that stiff polyacrylamide gels (323 kPa) prime macrophages towards a pro-inflammatory phenotype with impaired phagocytosis in macrophages, while soft (11 kPa) and medium (88 kPa) stiffness gels prime cells towards an anti-inflammatory, highly phagocytic phenotype. Furthermore, we show that stiffness dictates the migration mode of macrophages; on soft and medium stiffness gels, cells display Rho-A kinase (ROCK)-dependent, podosome-independent fast amoeboid migration and on stiff gels they adopt a ROCK-independent, podosome-dependent slow mesenchymal migration mode. We also provide a mechanistic insight into this process by showing that the anti-inflammatory property of macrophages on soft and medium gels is ROCK-dependent and independent of the ligand presented to them. Together, our results demonstrate that macrophages adapt their polarization, function and migration mode in response to the stiffness of the underlying substrate and suggest that biomaterial stiffness is capable of directing macrophage behaviour independent of the biochemical cues being presented to them. The results from this study establish an important role for substrate stiffness in directing macrophage behaviour, and will lead to the design of immuno-informed biomaterials that are capable of modulating the macrophage response after implantation. STATEMENT OF SIGNIFICANCE: Biomaterial implantation is followed by an inflammatory cascade dominated by macrophages, which determine implant acceptance or rejection through pro- and anti-inflammatory polarization states. It is known that chemical signals can direct macrophage polarization; however, recent evidence implicates biophysical cues in this process. Here we report that macrophages cultured on gels of varying stiffness adapt their polarization state, functional roles and migration mode according to the stiffness of the underlying substrate. The results from this study establish an important role for substrate stiffness in directing macrophage behaviour, and will lead to the design of immuno-informed biomaterials that are capable of modulating the macrophage response after implantation.
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ECM bioscaffolds deliver immunomodulatory signals through retained bioactive molecules and native-like architecture that influence immune cell activation, polarization, and effector function.
“As described in the previous section, ECM bioscaffolds deliver immunomodulatory signals through retained bioactive molecules and native-like architecture that influence immune cell activation, polarization, and effector function [48,80].”
From Immune Response to Extracellular Matrix Bioscaffolds: A Comprehensive Review (2025) · cites this paper as [48]
THP-1 monocytes differentiated into macrophages exposed to collagen-coated polyacrylamide gels with softer (11 kPa) and medium (88 kPa) stiffness turned into an anti-inflammatory phenotype, while higher (323 kPa) stiffness invoked a proinflammatory response combined with impaired phagocytosis.
“Gels that range between a softer (11 kPa) and medium (88 kPa) stiffness turned the cells into an anti‐inflammatory phenotype while a higher (323 kPa) stiffness invoked a proinflammatory response in macrophages combined with impaired phagocytosis.”
From Unraveling and Harnessing the Immune Response at the Cell–Biomaterial Interface for Tissue Engineering Purposes (2024) · cites this paper as [152]
The cellular means of migration is affected by stiffness, with a Rho-A kinase dependent fast amoeboid migration on gels with low to medium stiffness and a podosome dependent slow mesenchymal migration on stiffer gels.
“The cellular means of migration is also affected by stiffness, with a Rho‐A kinase dependent fast amoeboid migration on gels with a low to medium stiffness and a podosome dependent slow mesenchymal migration on stiffer gels.[ 152 ]”
From Unraveling and Harnessing the Immune Response at the Cell–Biomaterial Interface for Tissue Engineering Purposes (2024) · cites this paper as [152]
Current literature on the effects of material stiffness on macrophage activation presents conflicting results.
“However, current literature on the effects of material stiffness on macrophage activation presents conflicting results.”
From Soft tissue-mimicking hydrogel stiffness modulates polarisation of human monocyte-derived macrophages (2025) · cites this paper as [14]
Sridharan et al. found greater cell spreading and upregulation of two pro-inflammatory chemokines, such as CXCL11 and CCL20, on stiff polyacrylamide gels (323 kPa).
“Sridharan et al. found greater cell spreading and upregulation of two pro-inflammatory chemokines, such as CXCL11 and CCL20, on stiff polyacrylamide gels (323 kPa) 14”
From Soft tissue-mimicking hydrogel stiffness modulates polarisation of human monocyte-derived macrophages (2025) · cites this paper as [14]
In both studies, softer gels (> 11 kPa) promoted an anti-inflammatory phenotype.
“In both studies, softer gels (> 11 kPa) promoted an anti-inflammatory phenotype.”
From Soft tissue-mimicking hydrogel stiffness modulates polarisation of human monocyte-derived macrophages (2025) · cites this paper as [14]
The stiffness-dependent trend observed in this study aligns with previous reports that increased stiffness promotes a shift towards M1-like macrophage phenotype.
“The stiffness-dependent trend observed in our study aligns with several previous reports in which increased stiffness promoted a shift towards M1-like macrophage phenotype.”
From Soft tissue-mimicking hydrogel stiffness modulates polarisation of human monocyte-derived macrophages (2025) · cites this paper as [14]
Several studies have reported that stiffer substrates promote M1 polarisation.
“Several studies have reported that stiffer substrates promote M1 polarisation.”
From Soft tissue-mimicking hydrogel stiffness modulates polarisation of human monocyte-derived macrophages (2025) · cites this paper as [14]
Cites
Fiji: an open-source platform for biological-image analysis
Schindelin, J., Arganda-Carreras, I., Frise, E., Kaynig, V., Longair, M., Pietzsch, T., Preibisch, S., Rueden, C., Saalfeld, S., Schmid, B., et al. (2012) · Nature Methods · doi:10.1038/nmeth.2019 · Cited by 66,890 · see citing works
Matrix elasticity directs stem cell lineage specification
Engler, A. J., Sen, S., Sweeney, H. L., & Discher, D. E. (2006) · Cell · doi:10.1016/j.cell.2006.06.044 · Cited by 13,915 · see citing works
The chemokine system in diverse forms of macrophage activation and polarization
MANTOVANI, A., SICA, A., SOZZANI, S., ALLAVENA, P., VECCHI, A., & LOCATI, M. (2004) · Trends in Immunology · doi:10.1016/j.it.2004.09.015 · Cited by 6,534 · see citing works
Tissue Cells Feel and Respond to the Stiffness of Their Substrate
Discher, D. E., Janmey, P., & Wang, Y.-L. (2005) · Science · doi:10.1126/science.1116995 · Cited by 6,382 · see citing works
Protective and pathogenic functions of macrophage subsets
Murray, P. J., & Wynn, T. A. (2011) · Nature Reviews Immunology · doi:10.1038/nri3073 · Cited by 5,269 · see citing works
Foreign body reaction to biomaterials
Anderson, J. M., Rodriguez, A., & Chang, D. T. (2008) · Seminars in Immunology · doi:10.1016/j.smim.2007.11.004 · Cited by 5,138 · see citing works
Macrophage plasticity and polarization in tissue repair and remodelling
Mantovani, A., Biswas, S. K., Galdiero, M. R., Sica, A., & Locati, M. (2013) · The Journal of Pathology · doi:10.1002/path.4133 · Cited by 2,384 · see citing works
Effects of substrate stiffness on cell morphology, cytoskeletal structure, and adhesion
Yeung, T., Georges, P. C., Flanagan, L. A., Marg, B., Ortiz, M., Funaki, M., Zahir, N., Ming, W., Weaver, V., & Janmey, P. A. (2005) · Cell Motility and the Cytoskeleton · doi:10.1002/cm.20041 · Cited by 2,325 · see citing works
Understanding the Mysterious M2 Macrophage through Activation Markers and Effector Mechanisms
Rőszer, T. (2015) · Mediators of Inflammation · doi:10.1155/2015/816460 · Cited by 1,762 · see citing works
Garg, K., Pullen, N. A., Oskeritzian, C. A., Ryan, J. J., & Bowlin, G. L. (2013) · Biomaterials · doi:10.1016/j.biomaterials.2013.02.065 · Cited by 457 · see citing works
Fc-receptor-mediated phagocytosis is regulated by mechanical properties of the target
Beningo, K. A., & Wang, Y.-L. (2002) · Journal of Cell Science · doi:10.1242/jcs.115.4.849 · Cited by 389 · see citing works
Battiston, K. G., Labow, R. S., & Santerre, J. P. (2012) · Biomaterials · doi:10.1016/j.biomaterials.2012.08.014 · Cited by 53 · see citing works
Flagged first, then by citations
Cited by
Sorted by citations
Control of innate immune response by biomaterial surface topography, energy, and stiffness
Abaricia, J. O., Farzad, N., Heath, T. J., Simmons, J., Morandini, L., & Olivares-Navarrete, R. (2021) · Acta Biomaterialia · doi:10.1016/j.actbio.2021.04.021 · Cited by 199 · see citing works
TRPV4 plays a role in matrix stiffness-induced macrophage polarization
Dutta, B., Goswami, R., & Rahaman, S. O. (2020) · Frontiers in Immunology · doi:10.3389/fimmu.2020.570195 · Cited by 124 · see citing works
Matrix stiffness regulates macrophage polarisation via the <scp>Piezo1‐YAP</scp> signalling axis
Mei, F., Guo, Y., Wang, Y., Zhou, Y., Heng, B. C., Xie, M., Huang, X., Zhang, S., Ding, S., Liu, F., et al. (2024) · Cell Proliferation · doi:10.1111/cpr.13640 · Cited by 118 · see citing works
“26 Utilising atomic force microscopy (AFM), we analysed 16 positions of BMDM on soft, medium and stiff substrates and generated the typical mechanics heatmaps.”
MethodMechanosensing in macrophages and dendritic cells in steady-state and disease
Lee, M., Du, H., Winer, D. A., Clemente-Casares, X., & Tsai, S. (2022) · Frontiers in Cell and Developmental Biology · doi:10.3389/fcell.2022.1044729 · Cited by 99 · see citing works
Matrix stiffness‐mediated effects on macrophages polarization and their LOXL2 expression
Xing, X., Wang, Y., Zhang, X., Gao, X., Li, M., Wu, S., Zhao, Y., Chen, J., Gao, D., Chen, R., et al. (2021) · The FEBS Journal · doi:10.1111/febs.15566 · Cited by 92 · see citing works
Ezzo, M., Spindler, K., Wang, J. B., Lee, D., Pecoraro, G., Cowen, J., Pakshir, P., & Hinz, B. (2024) · Science Advances · doi:10.1126/sciadv.adp4726 · Cited by 82 · see citing works
Xie, Y., Wang, X., Wang, W., Pu, N., & Liu, L. (2025) · Journal of Translational Medicine · doi:10.1186/s12967-025-06422-5 · Cited by 80 · see citing works
Xiong, J., Xiao, R., Zhao, J., Zhao, Q., Luo, M., Li, F., Zhang, W., & Wu, M. (2024) · Journal of Translational Medicine · doi:10.1186/s12967-023-04810-3 · Cited by 79 · see citing works
ten Brink, T., Damanik, F., Rotmans, J. I., & Moroni, L. (2024) · Advanced Healthcare Materials · doi:10.1002/adhm.202301939 · Cited by 71 · see citing works
Physical cues in biomaterials modulate macrophage polarization for bone regeneration: a review
Yang, T., Fang, Z., Zhang, J., & Zheng, S. (2025) · Frontiers in Bioengineering and Biotechnology · doi:10.3389/fbioe.2025.1640560 · Cited by 50 · see citing works
Biomedical Implants with Charge‐Transfer Monitoring and Regulating Abilities
Wang, D., Tan, J., Zhu, H., Mei, Y., & Liu, X. (2021) · Advanced Science · doi:10.1002/advs.202004393 · Cited by 49 · see citing works
Zhang, Y., Dai, J., Hang, R., Yao, X., Bai, L., Wang, H., Huang, D., & Hang, R. (2024) · Biomaterials Advances · doi:10.1016/j.bioadv.2024.214010 · Cited by 26 · see citing works
Coser, C., Ghaemmaghami, A. M., & Yang, J. (2025) · Biomaterials Science · doi:10.1039/d5bm01187f · Cited by 17 · see citing works
Lei, M., & Chen, G. (2025) · Acta Biomaterialia · doi:10.1016/j.actbio.2025.05.011 · Cited by 12 · see citing works
Immune Response to Extracellular Matrix Bioscaffolds: A Comprehensive Review
Romero, D. J., Hussey, G., & Capella-Monsonís, H. (2025) · Biologics · doi:10.3390/biologics5030028 · Cited by 7 · see citing works
“As described in the previous section, ECM bioscaffolds deliver immunomodulatory signals through retained bioactive molecules and native-like architecture that influence immune cell activation, polarization, and effector function [48,80].”
- Authors
- Sridharan, R., Cavanagh, B., Cameron, A. R., Kelly, D. J., & O'Brien, F. J.
- Affiliations
- Royal College of Surgeons in Ireland (IE)
- Venue
- Acta Biomaterialia
- Publisher
- Elsevier BV
- Published
- 2019-04
- Volume
- 89
- Pages
- 47-59
- ISSN
- 1742-7061 (ISSN-L)
- OpenAlex
- W2920302920
- Cited by
- 450
- References
- 12
- Citations by year
- 2026: 64 · 2025: 83 · 2024: 66 · 2023: 65 · 2022: 72 · 2021: 56 · 2020: 37 · 2019: 7
- FWCI
- 22.79
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Acta Biomaterialia (publishedVersion)
- PubMed (publishedVersion)
- Funders
- SFI (SFI/12/RC/2278)
- AMBER
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Cellular Mechanics and Interactions
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Medicine › Hydrogels: synthesis, properties, applications
- Life Sciences › Immunology and Microbiology › Immunology › Immune cells in cancer
- Keywords
- macrophage polarization, substrate stiffness, macrophage migration, amoeboid migration, mesenchymal migration, podosomes, phagocytosis, anti-inflammatory macrophages, inflammatory macrophages, THP-1 cells, biomaterial design
- MeSH terms
- THP-1 Cells, Polyacrylamides, Acrylic Resins, Cell Movement, Collagen, Humans, Macrophages, Stress, Mechanical, Coated Materials, Biocompatible
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