Cells and Materials


Tissue interactions with discs of dermal sheep collagen (DSC), subcutaneously implanted in rats, were evaluated using transmission electron microscopy. DSC cross-linked with hexamethylenediisocyanate (HDSC) had already been tested previously. In the present study, we compared tissue interactions of non-cross-linked DSC (NDSC) and glutaraldehyde-cross-linked DSC (GDSC) with those of HDSC. To gain more insight in the relation between basophil-like cells, foreign body multinucleate giant (FBM-G) cells derived from them, and aluminum/silicate (Al/Si)-crystals, we also implanted agarose-embedded Al/Si-crystals. GDSC induced early after implantation extensive lipid formation, cell degeneration and death, but NDSC did not have any cytotoxic effects. Basophil-like (FBM-G) cells specifically dealt with Al/Si-crystals, because they were attracted by the agarose-embedded Al/Si-crystals. These cells were also attracted by GDSC and NDSC, where Al/Si-crystals are present. Accumulation of Al/Si-crystals was especially prominent with GDSC. Degradation by phagocytosis was in part carried out by FBM-G cells, derived from macrophages or fibroblasts, and observed only with GDSC, which indicates that the presence of cross-links is a prerequisite for their formation.