Type III collagen

Type III collagen is a fibrillar collagen of homotrimers containing α1(III) chains supercoiled around one another in a right-handed triple helix. Type III collagen is secreted by fibroblasts and other mesenchymal cell types, making it a major player in various inflammation-associated pathologies, such as lung injury, arthropathies, liver diseases, kidney fibrosis, hernia, and vascular disorders. Type III collagen and type I collagen are the main constituents of the interstitial matrix. Type III collagen mutations have been associated with Ehlers–Danlos syndrome, vascular deficiency, and aortic and arterial aneurysms. Several biomarkers for type III collagen formation and degradation have been developed and used extensively as investigatory tools in drug development and health care. In particular, the identification of biomarkers measuring the N-terminal propeptide of type III collagen as a marker of formation has proven valuable as a tool for monitoring liver fibrosis.