During development, collagen IV is ubiquitously distributed in BMs. During the maturation process, this network gets partially replaced in a remarkably tissue specific manner, defining BM structure and function. Collagen IV has been shown to bind to platelets, hepatocytes, keratinocytes, endothelial, mesangial, pancreatic cells and some tumor cells.

All collagen molecules are composed of three polypeptide chains arranged in a triple helical conformation, with a primary structure that is mostly a repeating motif with glycine in every third position and proline or 4-hydroxyproline frequently preceding the glycine residue. Type IV collagen occurs only in the basement membranes and contains up to six genetically distinct a-chains.

This is a lyophilized powder that can be reconstituted in sterile .5 M acetic acid, PBS or water at 1 mg/mL. A PBS solution will be stable for at least one year at -20°C. It is prepared by a modification of the pepsin extraction method of Glanville, R.W., et al.

An SDS polyacrylamide gel electrophoresis test run under reducing conditions consistent with basement membrane collagen yields three major bands.

Collagen is classified into a number of structurally and genetically distinct types. We use the nomenclature proposed by Bornstein and Traub. Be wary of confusing Sigma-type designations with recognized collagen classification types.