Collagen types in neocartilage tissue resulting from rib perichondrial graft in an articular defect--a rapid semi-quantitative methodology.

A method for estimating type II to type I collagen ratios in small tissue samples has been developed. The cyanogen bromide peptides of the tissue collagens were analyzed by SDS-gel electrophoresis. Marker peptides representative of each collagen type were established and their relative amounts determined by integration of the stained peptide bands following gel scans. Marker peptide ratios were then computed for each of several standard type II/type I mixtures and these peptide ratios were mathematically correlated with the corresponding type II/type I collagen ratios. A linear relationship between marker peptide ratio and collagen type ratio was established. This relationship was applied to the analyses of type II/type I ratios in samples of rib perichondrium and neocartilage derived from perichondrial graft repairs of full thickness femoral condyle defects. The results indicated that perichondrial grafts synthesize both types II and I collagens and that the proportion of type II increases with increasing post-transplant time.