T-cell abnormalities in antibody deficiency syndromes.

We studied two patients with hypogammaglobulinaemia, three with selective IgA deficiency, and four with selective extreme IgM deficiency for T-cell abnormalities in the circulating blood. Most patients had altered CD4+ helper/inducer and CD8+ suppressor/cytotoxic T-cell subsets, and an elevated percentage of HLA-DR+ and interleukin 2 (IL-2) receptor+ antigens on lymphocytes. One patient with the selective IgA deficiency had an absence of CD4+ T cells in blood. The lymphocytes of eight patients showed a diminished proliferative response and deficient IL-2 production in response to stimulation with phytohaemagglutinin or concanavalin A. The three patients with selective IgM deficiency were found to have a defective T-cell abnormality in IgM synthesis by B cells. It is interesting that CD8+ T cells of the two patients with IgM deficiency demonstrated suppressor cell function for IgM synthesis by the normal B and T cells.