Distribution of the collagen IV isoforms in human Bruch's membrane

Abstract

Aims: To determine the distribution of the α1 to α6 chains of type IV collagen in Bruch's membrane of the human posterior pole. Methods: Cryosections (10 µm) from 18 human eyes (20 months to 83 years old) were acid treated, blocked with 10% normal goat serum, incubated for 1 hour with monoclonal antibodies against type IV collagen isoform specific peptides at 1:75 dilution, and visualised with an ABC staining kit. Results: In Bruch's membrane, the α1(IV) and α2(IV) chains were identified in retinal pigment epithelial (10/18 = 55%) and choriocapillaris basement membranes (18/18 = 100%); the α3(IV), α4(IV), and α5(IV) chains were also found in the retinal pigment epithelial basement membrane (13/18 = 72%). In the choroid, the α1(IV) and α2(IV) chains were detected in the blood vessels (18/18=100%). The α6(IV) chain was not identified in any sections. Conclusion:The heterogeneous distribution of α1-2(IV) and α3-5(IV) in Bruch's membrane could give insights into the function of this structure in health, ageing, and diseases such as age related macular degeneration.

Retinal Abnormalities Characteristic of Inherited Renal Disease

“…These genes code for the chains that comprise the collagen IV ␣3␣4␣5 protomer which is found in the GBM, the stria vascularis of the cochlea, cornea, lens capsule, and internal limiting membrane, and Bruch's membrane of the retina. 48 Individuals with Alport syndrome have hematuria and develop kidney failure, hearing loss, corneal dystrophy, lenticonus, and retinopathy. Retinopathy is present in half the males and 1 in 5 females with X-linked disease, and probably the majority of those with recessive disease.…”

Deposition of Nidogens and Other Basement Membrane Proteins in the Young and Aging Mouse Retina

“…In addition, an individual basement membrane contains a unique set of more minor proteins. The expression and localization of laminin isoforms have been described in great detail for rat [6] and human [7] retinae, and the distribution of collagen IV isoforms in human Bruch's membrane is also known [8] . The presence of nidogen, presumably nidogen 1, in the retina has been noted, but the relative distribution of nidogen 1 and nidogen 2 has not been studied.…”

Morphometric analysis of human sciatic nerve perineurial collagen type IV content

“…More recent studies evaluated biochemical composition of BM by immunohistochemical methods. Distribution of collagen type IV isoforms in human Bruch's membrane was evaluated by Das et al (1990) and Chen et al (2003). Immunohistochemical distribution of BM proteins in human inner ear was studied by Ishiyama et al (2009).…”

“…There are literature data about aging changes of collagen type IV in BM of the human brain blood vessels (Uspenskaia et al, 2004), then blood vessels of the eye (Chen et al, 2003), ear (Ishiyama et al, 2009), and glomeruli in kidney (Anderson and Brenner, 1986;Bloom et al, 1959). First analysis of peripheral nerves extracellular matrix components were performed on rats (Lorimier et al, 1992).…”