Lymphocytes suppressing both immunoglobulin production and erythroid differentiation in hypogammaglobulinaemia

Abstract

CELLS blocking immunoglobulin (Ig) synthesis in vitro have been found among gradient-isolated blood mononuclear cells of individuals with variable immunodeficiency^1–4, immunodeficiency with thymona^1,3,4, infantile X-linked immunodeficiency⁴, multiple myeloma⁵ and Hodgkin's disease⁶. It has been suggested that the suppressor cells block terminal differentiation of human B lymphocytes⁷. The association of red cell aplasia and immunodeficiency states is well documented⁸. A circulating Ig capable of interfering with red cell formation has been demonstrated in several persons^9,10. The majority of individuals with these disorders, however, have no circulating inhibitor of erythro-poiesis. In the present study, lymphocytes from two persons with immunodeficiency with thymoma, one of whom had repeated episodes of red cell agenesis, were cocultivated in assay systems in which human blood B lymphocytes and human bone marrow erythroid precursors differentiate in vitro. The results suggest that the ‘suppressor’ cells observed in certain immunodeficiency diseases may act on both lymphocytic and haematopoietic target cells.