Pathobiology of epiretinal and subretinal membranes: possible roles for the matricellular proteins thrombospondin 1 and osteonectin (SPARC)

• Published in: Eye (London) Vol. 16; no. 4; pp. 393 - 403
• Main Authors: HISCOTT, P, HAGAN, S, HEATHCOTE, L, SHERIDAN, C. M, GROENEWALD, C. P, GRIERSON, I, WONG, D, PARAOAN, L
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Basingstoke Nature Publishing Group 01.07.2002
• Subjects: Biological and medical sciences; Epiretinal Membrane - metabolism; Epiretinal Membrane - pathology; Humans; Medical sciences; Ophthalmology; Osteonectin - physiology; Pigment Epithelium of Eye - pathology; Retinopathies; Thrombospondin 1 - physiology; Vitreoretinopathy, Proliferative - metabolism; Vitreous body disease; Human; Eye disease; Retinopathy; Epiretinal membrane; Hepatocyte growth factor; Pathogenesis; Osteonectin; Proliferative vitreoretinopathy; Thrombospondin
• ISSN: 0950-222X; 1476-5454
• DOI: 10.1038/sj.eye.6700196

Epiretinal and subretinal membranes are fibrocellular proliferations which form on the surfaces of the neuroretina as a sequel to a variety of ocular diseases. When these proliferations complicate rhegmatogenous retinal detachment (a condition known as proliferative vitreoretinopathy or PVR), the membranes often contain numerous retinal pigment epithelial (RPE) cells and a variety of extracellular proteins. The extracellular proteins include adhesive proteins like collagen, laminin and fibronectin. In addition, several matricellular proteins with potential counter-adhesive functions are present in the membranes. Two such matricellular proteins, thrombospondin 1 and osteonectin (or SPARC: Secreted Protein Acidic and Rich in Cysteine), tend to be co-distributed with the RPE cells in PVR membranes. By virtue of their counter-adhesive properties, thrombospondin 1 and SPARC may reduce RPE cell-matrix adhesion and so permit key RPE cellular activities (for example, migration or shape change) in periretinal membrane development. Furthermore, within a 'cocktail' containing other proteins such as the metalloproteinases and growth factors like the scatter factor/hepatocyte growth factor family, matricellular proteins may play a role in the RPE cell dissociation from Bruch's membrane, which characterises early PVR.