GLYCOSPHINGOLIPIDS IN CULTURED LENS EPITHELIAL-CELLS FROM DOG AND RHESUS-MONKEY

Vertebrate lens tissues contain several species of acidic and neutral glycosphingolipids in relatively high amounts. However, the epithelia with capsule from dog and rhesus monkey lenses had a simpler compositi on and lower content of glycosphingolipids than whole lenses. Ganglios ides and neutral glycosphingolipids in monolayer cultures of lens epit helial cells were also different from those in whole lenses. Although cy-galactosyl (Gal alpha 1-3Gal-R) or Lewis(x) (Gal beta 1-4[Fuc alpha 1-3]GlcNAc-R) epitopes were found in glycosphingolipids from whole le nses, they were not detected in those from monolayer cultures of dog a nd rhesus monkey lens cells. In addition, significant changes in gangl io-series gangliosides were induced in monolayer cultures of both cell s, where GM3 and GD3 were predominant. Immunofluorescence study reveal ed a characteristic distribution of cell surface gangliosides in confl uent monolayers. These findings suggest that glycosphingolipid synthes is in lens epithelia is intrinsically different from that in cortical and nuclear fibres, and that the expression of Lewis(x) and alpha-gala ctosyl epitopes in glycosphingolipids appears to be associated with th e differentiation of epithelial cells to fibres.