Collagen synthesis and turnover following particle phagocytosis in dermal fibroblasts.

Dermal fibroblast collagens were isolated after cold pepsin/acetic acid extraction and characterized by differentiated salt precipitation, agarose molecular sieve chromatography, CM-cellulose chromatography, and identification of cyanogen bromide cleavage peptides. Subsequent to particle phagocytosis, collagens recovered as secretory products from latex-treated cells were quantitatively less in total collagen and deficient in type III collagen. Although the total levels of hydroxyproline synthesized were similar to control cell populations, hydroxyproline recovered as non-dialyzable material was only 32% of the total hydroxyproline synthesize. Recovery of exogenous labeled collagen following dialysis, molecular sieve chromatography (Bio-Gel A-5m), and [14C]proline pulse-chase labeling of endogenous collagen, indicates that the alteration in types and quantities of recoverable collagen chains are primarily the result of rapid intracellular turnover.