Collagen type I and III fibers (COL1/COL3)

Collagen type I and III fibers are the primary structural components of the extracellular matrix (ECM), providing essential tensile strength and elasticity to tissues such as skin, bone, and blood vessels (UniProt P02452, P02461). Type I collagen is the most abundant protein in mammals, forming thick fibers that support high-stress tissues, while Type III collagen forms thinner reticular fibers and is particularly prominent in distensible organs and during the early stages of wound repair (PubMed: 28215447). In pathological states, the dysregulated and excessive deposition of these fibers is a hallmark of fibrotic diseases, including idiopathic pulmonary fibrosis, liver cirrhosis, and systemic sclerosis, where scarring leads to organ stiffness and failure (NIH: PMC7279134). Conversely, genetic mutations in the genes encoding these collagens result in connective tissue disorders such as Osteogenesis Imperfecta and Ehlers-Danlos Syndrome (StatPearls: NBK531479). Therapeutic strategies target these fibers by either promoting their enzymatic degradation using collagenases for conditions like Dupuytren's contracture or by inhibiting their synthesis and cross-linking through the modulation of myofibroblast activity and signaling pathways like TGF-beta (FDA: Xiaflex Label; PubMed: 25150430).

Other names

Type I collagenType III collagenFibrillar collagenCOL1A1/COL1A2COL3A1

Enzymatic degradation of collagen fibers, inhibition of collagen synthesis via TGF-beta pathway modulation, and stimulation of collagen production for tissue repair.