Isolation and serial propagation of malignant and normal cells in semi-defined media. Origins of CCRF cell lines.

Receivedfor publication January 8, 1960. comparatively few reports of the successful isola tion and serial propagation of new cell lines in these media or modifications thereof (4, 6, 11, 25, 30, 32, 46, 47, 52, 61). Soon after the initiation of a research program based upon mammalian cell culture in these labo ratories in 1956, it became evident that, in order to provide an adequate basis for the development of certain research problems, the number of cell lines then available for study in these media had to be increased, and accordingly a program of isolation was undertaken. The purpose of the present report