Control of ovarian cell growth in culture by serum and pituitary factors.

An ovarian cell line was developed that requires hormonal conditioning of the host for growth in vivo and that requires special factors for growth in vitro. It is necessary to prepare special culture media to demonstrate the effects of growth factors in vitro. To this end, methods were developed for removing from serum those essential factors required for the growth of ovarian cells in culture. Minimal growth occurred in medium containing fetal calf serum that had been passed through a porcelain filter. This method of depleting serum was replaced by a procedure involving passage through a carboxymethylcellulose column. Either pituitary extract or the eluate from the column restored growth in these depleted media. The eluate was more active than pituitary extract with regard to maximal growth enhancement. When the cells were incubated in the depleted media, viability, as measured by plating efficiency, decreased with incubation time. Either pituitary extract or the eluate from the column prevented such death of cells. Based on these findings, we postulate that the eluate contains both a survival factor and a growth-promoting factor for these ovarian cells, while pituitary extract contains only the survival factor.