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Studies of cell-extracellular matrix (ECM) interactions within fibrous systems such as collagen or fibrin are challenging, particularly if peri-cellular stiffness cannot be monitored. Here we present our light-based method for non-invasive patterning of molecular crosslinking combined with multi-axes optical tweezers active microrheology to map ECM stiffness landscapes. This method allows us to generate prescribed stiffness gradients and associated anisotropies, which model stiffness of the natural peri-cellular ECM. Patterned crosslinking induces strain hardening and measured stiffness gradients are in agreement with predicted strain fields. Migratory cells respond to these gradients as assessed by change in F-actin distribution and morphological properties.
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Diels–Alder Photoclick Patterning of Extracellular Matrix for Spatially Controlled Cell Behaviors
Abstract Strategies that mimic the spatial complexity of natural tissues can provide cellular scaffolds to probe fundamental questions in cell biology and offer new materials for regenerative medicine. Here, the authors demonstrate a light‐guided patterning platform that uses natural engineered extracellular matrix (ECM) proteins as a substrate to program cellular behaviors. A photocaged diene which undergoes Diels–Alder‐based click chemistry upon uncaging with 365 nm light is utilized. By interfacing with commercially available maleimide dienophiles, patterning of common ECM proteins (collagen, fibronectin Matrigel, laminin) with readily purchased functional small molecules and growth factors is achieved. Finally, the use of this platform to spatially control ERK activity and migration in mammalian cells is highlighted, demonstrating programmable cell behavior through patterned chemical modification of natural ECM.
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- PAR ID:
- 10508641
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 35
- Issue:
- 46
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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