Nullipotent teratocarcinoma cells acquire the pluripotency for differentiation by fusion with somatic cells.

By fusion of nullipotent embryonal carcinoma F9 cells with certain somatic cells freshly collected from differentiated tissues such as thymus and lens, pluripotent hybrid cell lines were obtained. They exhibited a wide spectrum of differentiation, including neural tubes, cartilages, skeletal muscles, ciliated epithelia and others, in solid tumors formed after injection into syngeneic mice. Cells from these tumors differentiated into several cell types when cultured in vitro. A possibility of the introduction of genes to code the factors for regulating differentiation into F9 cells by fusion is suggested.