Desmosterol as the major sterol in L-cell mouse fibroblasts grown in sterol-free culture medium.

The principal sterol synthesized by L-cell mouse fibroblasts is desmosterol. Cholesterol was not detected in these cells when they were grown in a sterol-free culture medium. These findings indicate that, in cells, cholesterol can be replaced by desmosterol. Sterol analyses of six other tissue culture cell lines revealed cholesterol synthesis.