Factors That Affect Human Hemopoiesis Are Produced by T Ce1I Growth Factor Dependent and Independent Cultured T-Cell Leukemia Lymphoma Cells

Some laboratory results and clinical situations suggest that human T cells may be important in the regulation of growth of hematopoietic cells. Since the discovery of T-cell growth factor (TCGF). systems are now available for the long-term specific in vitro propagation of mature normal or neoplastic human T cells. providing an opportunity to study the influence of T cells on hematopoiesis. Recently. 24 cell lines from patients with cutaneous T-cell lymphoma (CTCL) and T-cell acute lymphoblastic leukemia (T-ALL) were grown with TCGF and then assessed for release of humoral factors that affect hematopoiesis. Conditioned media (CM) from these cell lines were tested for erythroid burst-promoting activity (BPA) and granulocyte colonystimulating activity (CSA). BPA was detected in CM from