Induction of ICAM-1 Expression in Mouse Embryonic Fibroblasts Cultured on Fibroin-Gelatin Scaffolds

Culturing of allogeneic or autologous cells in three-dimensional bioresorbable scaffolds is an im-portant step in the engineering of constructs for regenerative medicine, as well as for experimental systems to study the mechanisms of cell differentiation and cell-to-cell interaction. Artificial substrates can modulate the phenotype and functional activity of immobilized cells. Investigating these changes is important for understand-ing the fundamental processes underlying cellular interactions in a 3D microenvironment and for improving tissue-engineered structures. In this study, we investigated the expression of the ICAM-1 adhesion molecule in mouse embryonic fibroblasts (MEF) when cultured on gelatin-fibroin scaffolds. Increased expression of ICAM-1 in MEF was detected only under 3D culture conditions both at the mRNA and protein levels. At the same time, the MEF cultured on various substrates did not oerexpress MAdCAM-1, indicating the selective effect of 3D culture conditions on ICAM-1 expression. One possible mechanism for ICAM-1 induction in MEF is associated with the activation of AP-1, since expression of c-Fos and Junb (but not cJun and Jund) was increased in MEF in 3D. When cultured under 2D conditions, the expression level of AP-1 components did not change.