The tissue transglutaminase activity does not strengthen cell adhesion during mechanical stretch

Tissue transglutaminase activity (tTGA) has been shown to be important in cell adhesion to an extracellular matrix (EM). However, it is not well know if tTGA improves cell adhesion during mechanical strains imposed on the EM. We have compared the adherence properties of NIH 3T3-fibroblast cell line on fibronectin (FN) and on an EM that lacks the 42KD tTG-binding site. The cells were plated on silicone membranes and were stretched 10% also. Results indicate cell loose their morphology in the absence of tTG binding site and mechanical stretch exacerbates this poor response. The presence of tTGA is important in initial cell adhesion but does not strengthen the cell adhesion to EM.