INFLUENCE OF IMMUNE STATUS OF THE IMMUNE DEFICIENT MICE ON THE METASTATIC PHENOTYPES OF THE HETEROGENEOUS CLONAL SUBLINES OF HUMAN LUNG GIANT CELL CARCINOMA

<正> By using cell cloning technique, 4 sublines (A,C,D,E) were isolated from a cell line of human lung giant cell carcinoma (PLA-801). After subcutaneous inoculation in T-cell deficient BALB/c nude mice, the incidence of tumor growth and spontaneous metastasis were the highest in subline D, moderate in sublines A and E, and lowest in subline C. Tumor cells of subline C also showed similar low tumorigenicity in another T-cell deficient 615/ PB1 nude mice.However, in 615/PB1 beige nude mice with con-genitally combined immune-deficiency in both T and NK cell activity, tumor cells of the rarely metastatic subline C do produce significantly high frequency of tumor growth and spontaneous metastasis.Morphological studies (light microscope, electron microscope and immunohistochemistry) showed rich microfilaments and Vimentin positive in the cytoplasm of metastatic tumor cells. This may imply a possibility that tumor cells differentiate towards the direction favourable to spreading and metastasis.