Serum-free cultivation of bovine lens epithelial cells

Mammalian cells in culture have individual nutritional requirements which are mainly fulfilled by the addition of fetal calf serum to the basic culture medium. Since many of the serum components are as yet poorly understood or even completely unknown, a number of difficulties arise in the evaluation of the effect of exogenously added factors or drugs on the growth of the cells. This paper presents data demonstrating the successful adaptation, routine cultivation and cryopreservation of bovine lens epithelial cells (BLEC) under serum-free culture conditions by use of the commercially available serum substitutes BMS, BM-86 Wissler and Ultroser G. Moreover, a culture medium especially designed for cell quiescence, named LR-1, is presented. Cells cultivated in culture medium containing 10% fetal calf serum served as controls. While BM-86 Wissler caused significantly reduced growth rates within 2 days and, finally, cell death after 12 days of incubation, the use of BMS resulted in growth rates which did not differ from the corresponding controls. Ultroser G resulted in a significant increase of proliferative activity of BLEC. LR-1 medium caused cell quiescence and kept the cells alive for a number of days. Thus, LR-1 allowed evaluation of the response of the cells to a mitogenic mixture from bovine brain mainly containing endothelial cell growth factor. The results demonstrate that cultivation of BLEC is possible under serum-free culture conditions. Moreover, the medium LR-1, which causes cell quiescence, is useful for the evaluation of growth factor-induced effects in vitro.