Clonal T-cell proliferation causing pure red cell aplasia in chronic B-cell lymphocytic leukaemia: successful treatment with cyclosporine following in vitro abrogation of erythroid colony-suppressing activity.

Clonal T cells that cause pure red cell aplasia were demonstrated in a patient with chronic B-cell lymphocytic leukaemia. The T-cell fraction was enriched by the immunomagnetic method and shown to have T-cell receptor-beta gene rearrangement. Cryopreserved T cells, obtained during the period of anaemia, suppressed autologous erythroid progenitor cell growth from remission marrow. The colony-suppressing activity was markedly improved by the addition of cyclosporine to the culture medium. The patient achieved haematological remission by cyclosporine monotherapy. Cyclosporine treatment may improve erythropoiesis in both a T-cell-dependent and a T-cell-independent manner.