[Transforming growth factor beta in the vitreous of patients with epiretinal proliferation]

Recent evidence suggests that TGF beta, a substance synthetized and released by Retinal Pigment Epithelial (RPE) cells, might play a role in fibrotic preretinal proliferation. We measured the concentration of this factor by radioreceptor assay in samples of vitreous obtained from 17 patients by vitrectomy. Seven had uncomplicated Retinal Detachment (RD) and 10 had either Proliferative Vitreoretinopathy (PVR) or Epimacular Membranes (EM). In the RD group, the mean concentration of TGF beta was 0.06 p mole/ml of vitreous, and in the PVR group, 0.21 p mole/ml. The total mitogenic activity of native vitreous and the amounts of a and b FGF in each sample were also measured, but were not different in the 2 groups. These results suggest that TGF beta is involved in the mechanism of excessive repair which characterises preretinal proliferation.