[Electron-immunostaining characteristics of platelet-derived growth factor, transforming growth factor beta1 and their receptors in epiretinal membranes].

OBJECTIVE

To investigate the ultrastructural distribution of platelet-derived growth factor (PDGF), transforming growth factor beta(1) (TGF-beta(1)) and their receptors in epiretinal membranes (ERM) and discuss the clinical significance of the distribution.

METHODS

25 membrane specimens were surgically removed by vitrectomy from 9 patients with rhegmatogenous retinal detachment. Double-staining techniques of immunoelectromicroscopy for eight antibodies (PDGF, TGF-beta(1), PDGF receptor subunits alpha and beta, TGF-beta subunits I and II, type I and III collagen) were used in these specimens as previously designed.

RESULTS

PDGF and TGF-beta(1) staining appeared to be stronger on early (< 2 months) and late (> 6 months) stage membranes than that of middle (2 - 6 months) stage of membranes, and the immunostaining intensity inverted with the degree of proliferative vitreoretinopathy (PVR). We found that the gold particles of PDGF and TGF-beta(1) tended to get together with that of type I and III collagen. In addition, the stainings of four growth factor receptors were frequently positive in a type of epithelial-like cells with rich cytoplasm components, and also the gold particles of PDGF and TGF-beta(1) were found around these cells.

CONCLUSIONS

A concentration change of PDGF and TGF-beta(1) exists in development of ERM throughout. The epithelial-like cells are of a type of active cells, and autocrine and paracrine activity may be involved in ERM pathogenesis. PDGF and TGF-beta(1) influence the contractile activity of ERM.