[Effect of antithymocyte globulin on bone marrow colony-forming capacity during defective myelopoiesis].

The effect of antithymocytic globulin (ATG) on colony-forming and claster-forming capacity (CFC and ClFC) of the bone marrow in vitro was studied in patients with hypoplastic anemia. 15 children in the initial stage of the disease and 6 patients before and after splenectomy were examined. The initial CFC and ClFC of the bone marrow were 1.84 +/- 0.55 and 1.92 +/- 0.32, respectively, per 10(5) myelokaryocytes. After the treatment of the bone marrow cell suspension with ATG the characteristics of CFC and ClFC remained unchanged: CFC amounted to 1.72 +/- 0.5 and ClFC to 1.81 +/- 0.27 per 10(5) cells (P greater than 0.05). It has been discovered after splenectomy that ATG produced no effect whatsoever on the colony-forming capacity of bone marrow granulocytic precursors.