Biohybrid corneal stromal tissue formation using keratocytes encapsulated in supramolecular microgels.

Compared to bulk hydrogels, microgels offer distinct advantages for biomedical applications. Their increased modularity and heterogeneity compared to hydrogels, combined with their small size and reversible dynamic bonding, enhance their suitability for minimally invasive cell delivery. Additionally, microgels offer greater control over porosity, resulting in the formation of intricate porous microstructures. In this work, keratocytes encapsulated in ureidopyrimidinone (UPy) supramolecular microgels functionalized with UPy-cRGD were fabricated to generate a micro stromal tissue in vitro. Both the human corneal keratocyte cell line (HCK) and primary keratocytes (PK) demonstrated effective cell-cell and cell-matrix mediated microgel assembly, resulting in the formation of self-generated scaffolds. The void spaces between the assembled microgels facilitate migration and infiltration of the cells through the biohybrid stromal tissue construct. The retention time of the cells within the microgels can be controlled by altering the microgel composition. Immunohistochemical analyses of PKs assembled tissues demonstrated the formation of stromal micro tissues, cellular extracellular matrix deposition and substantial upregulation of nuclear yes-associated-protein (YAP) during culture. This work highlights a novel supramolecular approach with promising potential for minimally invasive therapies aimed at treating corneal defects in clinical settings.