Abstract
The cell adhesion, migration and growth are fundamental processed controlling wound healing and tissue regeneration. We have reported that albumin conjugated with Arg-Gly-Asp (RGD) peptide, which has cell-adhesion promoting activity, has cellular adhesive activity comparable to fibronectin. In this study, we examined whether RGD-albumin conjugate (RGD-ALB) can promote the soft tissue ingrowth into porous matrix in vivo. Polyurethane sponge with 150-500 um pore size was prepared and used as a matrix. RGD-ALB, fibronectin (FN), albumin (ALB) were coated onto sponge surface, respectively. These sponges implanted in the subcutaneous tissue of rats were examined histologically. The inflammatory cells such as polymorphonuclear leukocyte (PMN) invaded into the deep inside of the RGD-ALB and FN coated sponge within 1 day after implantation. Both sponges exhibited rapid tissue ingrowth at 7th day postimplantation. On the other hand, the inflammatory cell invasion and the tissue ingrowth were markedly retarded for non-coated and ALB coated sponges. As RGD-ALB and FN were found to have little PMN chemotactic activity, the enhanced tissue ingrowth was mainly due to the cell adhesion activity. It was concluded that RGD-ALB can promote tissue activity at the initial stage of wound healing.
