In Vivo Interactions with (Tissue Culture Pretreated) Dermal Sheep Collagen
- PDF / 2,615,447 Bytes
- 8 Pages / 420.48 x 639 pts Page_size
- 43 Downloads / 188 Views
IN VIVO INTERACTIONS WITH (TISSUE CULTURE PRETREATED) DERMAL SHEEP COLLAGEN
P.B. van Wachem, M.J.A. van Luyn, L.H.H. Olde Damink*, P.J.Dijkstra*, J. Feijen* and P. Nieuwenhuis. Department of Histology and Cell Biology, Section Biomaterials Research, University of Groningen, Oostersingel 69/2, 9713 EZ Groningen, The Netherlands. *Department of Chemical Technology, University of Twente, p.o. Box 217, 7500 AE Enschede, The Netherlands.
ABSTRACT Pretreatment in tissue culture (TC) was previously found to markedly reduce the in vitro cytotoxicity of two types of crosslinked dermal sheep collagens (DSC's). This in vivo study confirms our in vitro results, in that TC-pretreatment of crosslinked DSC's resulted in the marked reduction or elimination of cytotoxic effects, such as increased cell infiltration, a deviant neutrophil-morphology, lipid formation and cell death. TC-pretreatment affected the crosslinked state of both DSC's in a different way, which could be deduced from the differences in gelatin-formation and presence of giant cells from macrophage- or fibroblast-origin. The results are explained in view of the differences in crosslinking.
INTRODUCTION Various collagen-based biomaterials have found applications in the biomedical field [1-3]. However, collagen-based biomaterials may induce cytotoxic effects [4,5]. Therefore, detailed evaluations, both in vitro and in vivo, are of importance., Our group is involved in both the in vitro [6-8] and in vivo [9,10] study of dermal sheep collagen (DSC). Three commercially available DSC's, a non-crosslinked version (NDSC), a hexamethylenediisocyanate (HMDIC)-crosslinked version (HDSC) and a glutaraldehyde (GA)crosslinked version (GDSC) are studied. With a new, advanced 6-day in vitro cytotoxicity test system [6-8], we found that exposure of HDSC to fibroblasts resulted in cytotoxic effects, with cell growth inhibitions of ± 50% and moderately deviant, i.e. fatty degenerative-like, cell morphology. With GDSC, the cell growth inhibition was ± 75% with highly deviant cell morphology, while NDSC induced an inhibition of only ± 20% without deviant cell morphology [7]. Repeated in vitro exposure of the tested materials considerably reduced cell growth inhibitions (unpublished results). In case of HDSC, four exposure-periods were needed to eliminate the inhibition on cell growth and to regain normal cell morphology, With GDSC, two exposureperiods resulted in a cell growth inhibition of below 10%; further exposure-periods (examined up to 7 times) always inhibited the cell growth with 10-20%, while slight deviances in morphology were still observed. No more cell growth inhibition was found with NDSC after two exposureperiods. In our in vivo studies with DSC's, we evaluated the tissue interactions with transmission electron microscopy (TEM) after subcutaneous implantations in rats [9,101. During the first 10 days after implantation, both HDSC- and GDSC-implants induced cytotoxic effects. With HDSC, a deviant morphology of neutrophils (disintegration of the cytoplasm), a moderate i
Data Loading...
