Tumor cell line characterization of a malignant histiocytosis transplanted into nude mice.

The successful transplantation of a human malignant histiocytosis into nude mice allowed the examination of its atypical histiocytic cell proliferation. Histiocytic type cells were identified by positive reactions with acid phosphatase and non-specific esterase and with anti human DR or OKI1 antisera. Presence of OKT9 antigen and negative results obtained with most OKT antisera, rosettes, erythrophagocytosis and lysozyme corroborate the histiocytic immature state of the cells and preclude another type of tumor. All positive tests to prove a mature mononuclear phagocytic origin were attributable to the murine host cell reaction.