RAPID CLONAL GROWTH AND SERIAL PASSAGE OF HUMAN-DIPLOID FIBROBLASTS IN A LIPID-ENRICHED SYNTHETIC MEDIUM SUPPLEMENTED WITH EPIDERMAL GROWTH-FACTOR, INSULIN, AND DEXAMETHASONE

A serum-free, hormone-supplemented medium, enriched with a mixture of lipids, was developed that supports rapid clonal growth of human diploid fetal lung fibroblasts (Flow 2000, WI-38, MRC-5 and IMR-90) and of low-passage human foreskin fibroblasts. The medium, which contains < 1 .mu.g total protein/ml, also supports serial passage of Flow 2000 cells under totally serum-free conditions. It provides lipid at a total of 10 .mu.g/ml as a liposome prepared from a mixture of soybean lecithin, cholesterol sphingomyelin, vitamin E and vitamin E acetate. The sobyean lecithin, which contains a variety of naturally occurring phospholipids, can be replaced with a mixture of highly purified phospholipids. Except for possible contaminants in the substances used in its preparation, the serum-free medium is fully defined chemically. It consists of an optimized basal nutrient medium, MCDB 110, supplemented with insulin, epidermal growth factor, dexamethasone, prostaglandin[PG]E1 and F2.alpha., phosphoenolypyruvate, dithiothreitol, glutathione and the lipids listed above.