TISSUE REACTION TO SUBCUTANEOUS IMPLANTATION OF A COLLAGEN SPONGE - A HISTOLOGICAL, ULTRASTRUCTURAL, AND IMMUNOLOGICAL STUDY

The biocompatibility of a subcutaneously implanted bovine collagen sponge (Haemostagen) was studied in rats by analyzing tissue reactions up to 3 months by histological and ultrastructural methods; in addition, the level of serum antibodies to bovine type I collagen (the major implant collagen) was measured by solid‐phase radio‐immunoassay. By 8 h after implantation, the implant was completely filled with polymorphonuclear cells (PMNs). After 8 days, fibroblasts had developed a granulation tissue within the sponge and the PMNs had almost disappeared. The small residue that remained after 1 month consisted of some densely packed collagen fibrils containing giant cells, which had disappeared by 3 months. No antibodies to bovine type I collagen were found in the sera of implanted rats. Copyright © 1990 John Wiley & Sons, Inc.