We attempted to induce in vivo clonal growth of neoplastic lymphoid cells from fresh specimens of involved tissue from 22 patients with no-Hodgkin lymphoma (NHL). Conditioned media derived from two human B-lymphocyte tissue culture lines were tested for their ability to promote colony growth. In addition, we compared the incidence of colony induction to the flash-3H-thymidine labeling index (LI) of the cells in the tissues cultured. Successful colony induction occurred in three-tenths of the cases of diffuse histiocytic lymphoma and one-half of the cases of nodular lymphoma. Cloning efficiencies were low, ranging from 0.0003 to 0.04%. There was no apparent relationship between successful instances of cloning and LI. We have confirmed the observations of Jones et al that lymphoid tumor cells can be cloned from tissues involved by NHL using a soft agar system. The possibility of using such systems for clinical predictive assays of chemotherapeutic drug toxicity toward tumor cells of NHL is discussed. We conclude that further refinements of the assays are desirable before they can be applied to widespread clinical use.
