Differentiation of rat lens epithelial cells in tissue culture—IV. Some characteristics of the process, including possible in vitro models for pathogenic processes in cataractogenesis

Abstract

In this paper a number of our observations on cultured rat lens epithelial cells are discussed, and some parallels are drawn with some other systems. Several stages of differentiation of rat lens epithelial cells in tissue culture are outlined along with the criteria used to define them. The effects of several factors including cell density, medium and hormonal factors such as cyclic AMP on differentiation are discussed. The behaviour of primary cells in culture, seen on a time-lapse video tape available from the authors, is outlined. Actin and tubulin both appear to be involved in the elongation stage of primary cells in culture. Cold shock appeared to induce γ-crystallin protein detectable by immunofluorescence in a cell line, RLE-R, obtained by treatment of primary cultures with Rous Sarcoma virus. A second cell-line, RLE-MM, obtained after similar treatment with murine leukemia and murine sarcoma cells is reported. A number of possibilities for modelling various aspects of the globular degeneration occurring in cataracts is reported, including globules formed in old 16-day-embryo cultures, globules formed in primary cells after treatment with cytochalasin D, and in the cell-line RLE-R following cold shock. Glucose toxicity to cells of the line RLE-R, which may also be a contributing factor in diabetic cataracts, was relieved by vitamins E and C which appeared to act additively. Several problems remaining are discussed.