To understand the molecular events underlying disease-related vitreous gel contraction, the effect of serum components on collagen was investigated.
Bovine vitreous or dermal collagen was incubated with a mixture of transglutaminase (TG; factor XIIIa) and fibronectin (FN), and biochemical changes in collagen were monitored by gel electrophoresis. In addition, serum-induced changes in collagen gel volume were monitored.
Gel electrophoresis revealed a new band of high molecular weight (M(r) 240,000), presumably due to intermolecular crosslinks of collagen and FN peptides. Whey components were also shown to cause a significant decrease in collagen gel volume. CONCLUSION. Collagen gel contraction could be attributed to collagen-FN-collagen crosslinks catalyzed by TG.