Characterization of a new human cell line derived from a xenografted embryonal carcinoma

A human cell line has been established from a transplantable xenografted human testicular tumor, which, both in the original tumor and in the xenograft, exhibited the histological characteristics of an undifferentiated malignant teratoma (embryonal cell carcinoma). The cells in culture were undifferentiated by biochemical, morphological, and ultrastructural criteria, growing as small islands of cells that tended to form aggregates at high density. The cells showed some variation in chromosome number with 30 to 40% of the cells having a normal human karyotype. The cells expressed high levels of alkaline phosphatase, which by heat inactivation and inhibition studies was 40 to 50% placental type alkaline phosphatase. None of the cultures produced human chorionic gonadotrophin, alphafetoprotein, carcinoembryonic antigen, or fibronectin, although at high cell densities plasminogen activator could be detected at low levels. Cell surface studies showed that the cells shared antigens with the murine embryonal carcinoma cell line F9, expressed beta 2-microglobulin at very low and variable levels, and bound the lectin peanut agglutinin. These studies suggest that this cell line has some of the characteristics described for murine embryonal carcinoma cell lines.