Zj. Fan et al., INHIBITION OF FIBROBLAST PROLIFERATION BY HUMAN IRIS PIGMENT EPITHELIAL-CELLS IN-VITRO - PRELIMINARY-RESULTS, Graefe's archive for clinical and experimental ophthalmology, 234(1), 1996, pp. 64-66
Background: The interaction between different cells plays an important
role in many physiological and pathological processes. Since the prol
iferation of fibroblasts is very much involved in the pathogenesis of
eye diseases such as proliferative vitreoretinopathy, the failure of f
iltration in glaucoma surgery, etc., we attempted to ascertain whether
iris pigment epithelial cells (IPE) have some modulating effect on fi
broblast proliferation. Methods: Human IPE were explanted and the thir
d-passage culture was transferred into serum-fi ee RPMI-1640 medium. A
fter 48 h of further incubation, the medium was collected and submitte
d to centrifugation; the supernatant was used as the conditioned mediu
m of IPE (IPE-CM). Cultured fibroblasts from Tenon's capsule were seed
ed in a 96-well plate and incubated with IPE-CM in different concentra
tions. The proliferation of fibroblasts was estimated by thymidine inc
orporation and cell counting. Results: The incorporation of tritiated
thymidine by fibroblasts was reduced to 56.68% of baseline with 1:16 d
iluted IPE-CM and to 13.63% and 8.20%, respectively, with 1:8 and 1:2
diluted IPE-CM. These findings were in good accordance with the result
s of cell counting! performed in parallel. SDS-PACE of IPE-CM revealed
two specific bands with molecular weight 65 kDa and 40 kDa. Conclusio
n: IPE-CM showed an obvious dose-dependent inhibitory effect on fibrob
last proliferation and was presumed to contain some active factors con
tributing to this effect.