Purchase this article with an account.
R. Li, A. Maminishkis, F.E. Wang, S.S. Miller; Inflammatory Cytokines and Specific Platelet Derived Growth Factors (PDGF) Alter Human Fetal Retinal Pigment Epithelia (hfRPE) Migration and Proliferation . Invest. Ophthalmol. Vis. Sci. 2006;47(13):2877.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Abnormal proliferation or migration of RPE cells occurs in a variety of degenerative eye diseases, such as retinitis pigmentosa (RP) or proliferative vitreoretinopathy (PVR). Various growth factors (PDGF) and cytokines are known to be associated with degenerative ocular diseases and can induce RPE migration and proliferation. In this study we examined the ability of PDGF isoforms and a cocktail of cytokines to alter hfRPE proliferation and migration.
For the migration assay, confluent hfRPE monolayers were treated with mitomycin C and were scratched using a specially designed tool. Different PDGF isoforms (AA: 10 – 50 ng/ml, BB: 10 – 50 ng/ml; AB: 10 – 50 ng/ml; CC: 100 – 500 ng/ml – concentrations recommended by the manufacturer) or cytokine cocktail (TNFα–10 ng/ml; IL1ß–10ng/ml; IFNγ–100 U/ml) were added for 72 hrs. hfRPE cell proliferation was determined using a standard BrdU based proliferation kit. RT–PCR was used to confirm the presence of PDGF receptors. Affymatrix human U133 V2.0 chips were run in duplicate for each total RNA sample (total 4 chips).
All PDGF isoform messages were detected in hfRPE. PDGF C and D are more abundant than PDGF A and B and ranked 1248 and 3403 out of 54,675 transcripts on the chip. PDGFR ß is more abundant than α. In preliminary experiments, four different isoforms of PDGF were tested in hfRPE proliferation/migration assays. Addition of the AB (50 ng/ml) and BB isoforms (50 ng/ml) of PDGF to hfRPE cells caused an increase in RPE migration (n=4) and proliferation by 91 and 43%, respectively (n = 2). Surprisingly, other isoforms (AA: 10–50 ng/ml, CC: 100 – 500 ng/ml) did not significantly alter RPE migration or proliferation. Presence of both PDGF receptor α and ß was confirmed using RT–PCR. Both isoforms AB and CC bind to the same receptors (PDGFR–αα and PDGFR–αß) but produce opposite results. However, their biological effects on the human RPE cells are distinct. This may suggest inhibitory mechanisms in these cells for the activity of PDGF–CC. Further analysis of their intracellular pathway and testing the effect of PDGF–DD on such cells is warranted. In contrast to PDGF, the cytokine cocktail almost completely inhibited migration (n=2) and proliferation (n=2) of hfRPE cells.
Inhibition of proliferation/migration by the cytokine cocktail provides a possible mechanism or identifies a set of pathways that could be important for mitigating the progression of retinal degenerative diseases such as PVR mediated by growth factors such as PDGF.
This PDF is available to Subscribers Only