bims-ecemfi 2025-08-03 papers

Nat Commun. 2025 Jul 25. 16(1): 6870

Mammalian cells measure the extracellular matrix area and respond through switching the adhesion state.

Xiaole Wang, Pengli Wang, Lihang Zhang, Tianyu Xu, Seungkuk Ahn, Upnishad Sharma, Han Yu, Nico Strohmeyer, Daniel J Müller.

Mammalian cells adjust integrin-mediated adhesion based on the composition and structure of the extracellular matrix (ECM). However, how spatially confined ECM ligands regulate cell adhesion initiation remains unclear. Here, we investigate how cells adapt early adhesion to different ECM protein areas. Through combining microcontact printing with single-cell force spectroscopy we measure cell adhesion initiation and strengthening to defined areas of ECM proteins. HeLa cells and mouse embryonic fibroblasts gradually increase adhesion with collagen I or fibronectin area, while reaching maximum adhesion force to ECM patterns having areas above certain thresholds. On much smaller patterns, both cell types switch to a different state and considerably increase the adhesion force per ECM protein area, which they strengthen much faster. This spatially enhanced adhesion state does not require talin or kindlin, indicating a fundamentally different adhesion mechanism. Mechanotransduction seems to play integrin and cell type-specific roles in the spatially enhanced adhesion state.

DOI: https://doi.org/10.1038/s41467-025-62153-7

Acta Biomater. 2025 Jul 29. pii: S1742-7061(25)00569-0. [Epub ahead of print]

Anisotropic Hydrogel Degradation Enhances 3D Collective Mesenchymal Stromal Cell Alignment, Mechanotransduction and Osteogenic Differentiation.

Claudia A Garrido, Daniela S Garske, Christian H Bucher, Shahrouz Amini, Georg N Duda, Katharina Schmidt-Bleek, Amaia Cipitria.

Tissue engineering involves assembling cells and mimicking the complex anisotropic architecture of biological tissues to perform specific functions. This study uses 3D alginate-based hydrogels with RGD binding motifs to explore the impact of anisotropic degradation of patterned hydrogels (two components: degradable (Deg) and non-degradable (noDeg)) compared to single-phase materials (one component: Deg or noDeg), on the potential of enhancing cell spreading, collective alignment, mechanotransduction and osteogenic differentiation of encapsulated human mesenchymal stromal cells (hMSCs). Spatial patterns of Deg and noDeg subregions are formed by photolithography: UV-triggered thiol-ene crosslinking with matrix metalloprotease (MMP) sensitive peptides form Deg phases, while non-UV exposed regions result in Diels-Alder spontaneous click crosslinking and noDeg phases. 3D patterns in hydrogel degradation enhance hMSC spreading and allow collective cell alignment in Deg areas, while cells remain rounded with no alignment in noDeg regions. In addition, we observe a boosted osteogenic differentiation when compared to single-phase materials, as mid osteogenic markers (osteocalcin) are expressed at day 14 in anisotropic gels, whereas in single-phase only early osteogenic markers are found (osterix). Mechanosensing pathways were evaluated using the expression and localization of YAP. Deg sections in patterned materials have an enhanced nuclear translocation and higher YAP expression compared to single-phase Deg materials and noDeg sections. This effect is lost and no patterns in YAP expression and localization emerge when using an MMP-scramble peptide or no-RGD materials. These findings demonstrate that 3D patterns in alginate hydrogel degradation guide hMSC spreading, collective alignment, enhance YAP nuclear translocation and osteogenic differentiation. Mimicking tissue anisotropy in 3D patterned hydrogels could have broad applications in biofabrication and tissue engineering. STATEMENT OF SIGNIFICANCE: Patterned materials integrate multiple characteristics within a single material, closely mimicking the anisotropy found in tissues. This research goes further by demonstrating how anisotropic degradation of cell-laden hydrogels leads to emerging patterns in mechanics. As a consequence, anisotropic hMSC morphology and collective alignment are observed in 3D patterned materials compared to single-phase counterparts. Additionally, we show enhanced and spatially guided hMSC osteogenic differentiation in patterned materials. Furthermore, anisotropic mechanosensing via YAP/TAZ signaling is shown to mediate this enhanced and spatially guided mechanotransduction and osteogenic differentiation. Finally, we explore how additional biochemical stimuli can further boost the spatially guided hMSC osteogenic differentiation. These findings advance our understanding of cell response in anisotropic microenvironments, with broad applications in biofabrication and tissue engineering.

Keywords: 3D patterned degradation; YAP expression; YAP nuclear translocation; alginate; anisotropic dual crosslinking; collective cell alignment; mechanotransduction; osteogenic differentiation; primary human mesenchymal stromal cells (hMSC)

DOI: https://doi.org/10.1016/j.actbio.2025.07.063

Adv Nanobiomed Res. 2025 Jan;pii: 2300110. [Epub ahead of print]5(1):

Polymer design of microwell hydrogels influences epithelial-mesenchymal interactions during human bronchosphere formation.

Madeline K Eiken, Justin E Levine, Shinyeong Lee, Samantha Lukpat, Eleanor M Plaster, Vikram Bala, Jason R Spence, Claudia Loebel.

Bronchospheres have emerged as a promising in vitro model towards probing questions on organ development and disease. Several organoid models, including from airway (e.g., bronchial, tracheal) cells, require 3D Matrigel, a complex mouse tumor-derived matrix that typically leads to heterogenous size and structures. Synthetic and naturally-derived polymeric hydrogels show increased opportunities as an alternative to Matrigel culture. In addition, recent advances in hydrogel-based microcavities (i.e., microwells) have shown improved control over organoid size, structure, and composition. Here, we build upon this approach and describe the fabrication and characterization of microwell hydrogels based on other polymers, including diacrylated poly(ethylene glycol), agarose, methacrylated gelatin, and norbornene-modified hyaluronic acid. Using these microwell hydrogels, human bronchial epithelial cells and lung fibroblasts readily assemble into viable cyst-like bronchospheres. Our study shows that the cellular composition regulates the formation and structure of the bronchosphere which is also regulated by the type and adhesiveness of the hydrogel. Furthermore, both hydrogel type and cellular composition influence the amount and composition of deposited ECM within the microwells. This hydrogel fabrication platform provides an accessible in vitro culture platform for the formation and growth of bronchospheres which can be extended to the culture of other stem/progenitor and tissue-derived organoids.

Keywords: bronchospheres; hydrogels for cell culture; microwells

DOI: https://doi.org/10.1002/anbr.202300110

Adv Healthc Mater. 2025 Jul 29. e00389

Interplay between Matrix Viscoelasticity and Integrin Engagement Modulates Cancer-Associated Fibroblast States.

Yunyun Wang, Zixuan Zhao, Nicholas Ching Wei Ho, Narayanan Gopalakrishna Iyer, Eliza Li Shan Fong.

With the recent advent of single-cell transcriptomics, it is increasingly evident that cancer-associated fibroblasts (CAFs) are heterogeneous and exist as different subsets. These distinct CAF subsets likely harbor unique functions, most of which have not been fully elucidated. Efforts to understand CAF subset function and develop therapeutic strategies are currently hampered by the lack of robust preclinical models that controllably recapitulate CAF heterogeneity in vitro. Previous studies have suggested that CAF plasticity can be controlled through modulation of culture matrix parameters. In this study, it is hypothesized that hydrogel viscoelasticity and integrin engagement would influence the plasticity of encapsulated CAFs, specifically skewing CAFs to adopt either the myofibroblastic CAF (myCAF) or inflammatory CAF (iCAF) state. Using alginate hydrogels, it is found that patient-derived CAFs exhibit different morphologies and transcriptomic profiles reminiscent of the myCAF or iCAF subsets, depending on hydrogel viscoelasticity and cell adhesion. Furthermore, it is shown that the JAK/STAT signaling pathway is important for iCAF maintenance and could be leveraged to alter CAF states. Taken together, how matrix viscoelasticity coupled with integrin engagement modulates CAF states in vitro is demonstrated for the first time. The developed CAF models may be highly useful for understanding CAF function and to develop CAF-targeted therapies.

Keywords: JAK/STAT signaling pathway; cancer‐associated fibroblast; viscoelasticity

DOI: https://doi.org/10.1002/adhm.202500389