Localization and Distribution of Cartilage Oligomeric Matrix Protein in the Rat Intervertebral Disc

Abstract

Our results demonstrate the expression of COMP in both the AF and NP of the IVD. COMP is a component of the extracellular matrix of AF and NP, with a lamellar distribution pattern in the AF. Our data suggest that COMP may play a role in the normal structure of IVD.

A phenotypic comparison of intervertebral disc and articular cartilage cells in the rat

“…Recently, Risbud et al, suggested that hypoxia inducible factor 1a (HIF-1a) could be used to distinguish NP cells and articular chondrocytes [38]. NP cells uniquely expressed functionally active HIF-1a protein under normoxic conditions and only modestly increased their HIF-1a [36,45,46] vim Intermediate filament typically co-expressed with k19; expression reported in AF cells, large (''notochordal'') and small (''chondrocytic'') cells of the NP, and notochord cells; expression also documented in cartilage [3,7,21,22] anx3 Ca 2+ and phospholipid binding protein; influences membrane organization and traffic; regulates Ca 2+ currents across membranes and/or intracellular Ca 2+ concentrations [12] comp Extracellular matrix glycoprotein that can cross-link type-II collagen; found abundantly in articular cartilage; also identified in NP and AF [8,20,39] mgp Vitamin-K dependent protein found in bone and cartilage; expression up-regulated in endochondral bone formation, pathological calcification of cartilage, and immature and periosteal hypertrophic chondrocytes during fracture healing [2,15,16,23,24,33] transcriptional activity in a low-oxygen environment. In contrast, AF cells, chondrocytes and osteoblasts showed low-level expression of HIF-1a under normoxia, with significant protein induction at hypoxia.…”

Fibrotic-like changes in degenerate human intervertebral discs revealed by quantitative proteomic analysis

“…Aggrecan is the major PG in IVD, forming large aggregates with hyaluronan 7 . Small leucinerich proteoglycans (SLRPs), including decorin, biglycan, lumican, fibromodulin, and chondroadherin are detected in the IVD 8e10 , also fibronectin 11 , cartilage intermediate layered protein (CILP) 12 , cartilage oligomeric matrix protein (COMP) 13 and thrombospondin 14 . These molecules interact and contribute to matrix integrity, providing tensile strength while retaining water to resist compressive forces.…”

The presence of stem cells in potential stem cell niches of the intervertebral disc region: an in vitro study on rats

“…Rats were chosen as the experimental model since they are commonly used in IVD research [24][25][26]. Considering that the perichondrium region adjacent to the EP may be the common origin of stem cells in the NP, CEP, and AF (including AFo), we chose this region as the target ISN area [24].…”