INFLUENCE OF LITHIUM ON PROLIFERATION OF HEMATOPOIETIC STEM-CELLS

  • 1 January 1981
    • journal article
    • research article
    • Vol. 9  (7) , 804-810
Abstract
Since Li induces granulocytosis, Li has been proposed as a means for reversing the neutropenia associated with cancer chemotherapy. The effect of Li on normal marrow hematopoiesis was studied by determining the numbers of pluripotential (CFU[colony forming cell]S [stem cell]) and committed stem cells (CFUC [granulopoietic CFU], CFUE [erythroid CFU] and BFUE [erythroid burst forming units]) after in vitro and in vivo exposure to Li in mice. In the presence of 1 meq/l Li in vitro, marrow CFUS and CFUC were increased; higher concentrations (.gtoreq. 5 meq/l) were inhibitory. Marrow CFUE and BFUE were decreased at concentrations of Li .gtoreq. 0.5 meq/l. In vivo (0.5-5.0 meq/l i.p.), Li produced similar results to those obtained in vitro with striking CFUC enhancement. Serum from these Li-treated mice contained increased colony stimulating factor (CSF). In the Dexter continuous marrow culture system, Li stimulated increased CFUC production from the non-adherent fraction. These in vitro and in vivo studies document the ability of Li to modulate hematopoiesis by influencing pluripotential and committed stem cell proliferation and differentiation towards granulopoiesis, apparently at the expense of erythropoiesis. Mechanisms of this modulation are discussed.