Engineered endothelial cell adhesion via VCAM1 and E-selectin antibody-presenting alginate hydrogels

Materials that adhere to the endothelial cell (EC) lining of blood vessels may be useful for treating vascular injury. Cell adhesion molecules (CAMs), such as endothelial leukocyte adhesion molecule-1 (E-selectin) and vascular cell adhesion molecule-1 (VCAM1), modulate EC-leukocyte interactions. In this study, we mimicked cell-cell interactions by seeding cells on alginate hydrogels modified with antibodies against E-selectin and VCAM1, which are upregulated during inflammation. ECs were activated with interleukin-1α to increase CAM expression and subsequently seeded onto hydrogels. The strength of cell adhesion onto gels was assessed via a centrifugation assay. Strong, cooperative EC adhesion was observed on hydrogels presenting a 1:1 ratio of anti-VCAM1:anti-E-selectin. Cell adhesion was stronger on dual functionalized gels than on gels modified with anti-VCAM1, anti-E-selectin or the arginine-glycine-aspartic acid (RGD) peptide alone. Anti-VCAM1:anti-E-selectin-modified hydrogels may be engineered to adhere the endothelium cooperatively.