EFFECT OF CROSS-LINKING METHOD ON COLLAGEN FIBER-FIBROBLAST INTERACTIONS

Collagen, the major structural protein of the extracellular matrix in animals, is a versatile biomaterial used in various tissue engineering applications. Crosslinking influences the mechanical properties, reso rption kinetics, and biocompatibility of collagen-based biomaterials. In this study, we evaluated the effects of crosslinking on collagen fi ber-fibroblast interactions in vitro. Collagen fibers were left untrea ted or crosslinked by ultraviolet (UV) irradiation, dehydrothermal (DH T) treatment (3 or 5 days), or hexamethylenediisocyanate (HMDIC) expos ure. The initial attachment, proliferation (through 8 days), and morph ology of human dermal fibroblasts were evaluated on control and crossl inked bundles of 200 collagen fibers in vitro. Initial attachment (num ber of fibroblasts at day 0) was increased on UV and DHT5-treated coll agen fiber bundles. Fibroblast proliferation was similar for control, UV crosslinked, and DHT crosslinked fibers. In contrast, fibroblast at tachment was significantly decreased and proliferation was delayed on HMDIC crosslinked fibers. These results, coupled with our previous stu dies, suggest that UV crosslinking of collagen fibers provides a combi nation of biocompatibility, mechanical properties, and strength retent ion suitable for various tissue engineering applications. (C) 1997 Joh n Wiley & Sons, Inc.