A Megakaryocytic Thrombocytopenia Associated with an Excess of Leu 2a+ Suppressor Cells

Abstract
Eight patients with acute myeloid leukemia (AML), either at presentation or in remission, had normal T-cell subsets as defined by Fc receptors and monoclonal antisera. In contrast, a persistant excess of T lymphocytes staining with Leu 2a ( defining suppressor cells) was noted in a case of AML in which persistant amegakaryocytic thrombocytopenia occurred after other hemopoietic lines had recovered from ablative chemotherapy. Apparently, the 2a+ cells were involved in the suppression of megakaryocytopoiesis. The phenotype of the lymphoid cells is compared and contrasted with previously described cases of other cytopenias associated with an excess of suppressor cells.