DMSO mimics inhibitory effect of thalidomide on choriocapillary endothelial cell proliferation in culture.

AIM To evaluate the effect of thalidomide on bovine choriocapillary endothelial cell proliferation. METHODS Posterior segments of bovine eyes were incubated with trypsin. After digestion of the tapetum, pieces of Bruch's membrane with the adherent choriocapillaris were scraped, digested again with a cocktail of enzymes, washed and cultured in MCDB 131 medium. Cells were incubated with 100 micro g/ml thalidomide (dissolved in DMSO as recommended). Control cultures were incubated with DMSO alone or without any supplement. Cell proliferation after 24 hours was determined in a counting chamber. Purity of the cultures was controlled by immunohistochemical staining and labelling with low density lipoprotein. RESULTS Thalidomide dissolved in DMSO inhibited proliferation of choriocapillary endothelial cells compared to control cultures incubated without any supplement. However, DMSO alone suppressed cell proliferation equally well. CONCLUSION In cultured bovine choriocapillary cells the inhibiting effect of thalidomide may at least in part be attributed to the solvent DMSO alone.