T cell-mediated inhibition of haematopoiesis in aplastic anaemia: serial assay of inhibitory activities of T cells to autologous CFU-E during immunosuppressive therapy.

T cell-mediated inhibition of autologous erythroid colony formation was found in two patients with aplastic anaemia. Each patient was treated separately with ALG and methylprednisolone. Peripheral blood T cells were cryopreserved serially during the course of the disease. The inhibitory activity of T cells was assayed after remission using autologous bone marrow. The inhibitory activity of T cells was lost following the treatment and preceded haematopoietic recovery.