Impaired production of interleukins in patients with cell-mediated immunodeficiencies.

The poor mitogen response to phytohaemagglutinin (PHA) of lymphocytes from three patients with cell-mediated immunodeficiencies was restored to normal when supernatants containing interleukin 2 (IL-2) were added. One of three children with severe combined immunodeficiency also showed a partial response. There was no improvement in the normal mitogenic response of the lymphocytes from patients with either the X linked or common variable forms of hypogammaglobulinaemia. All three patients with cell-mediated immunodeficiencies showed gross imbalance in the ratio of helper/inducer (OKT4+) to suppressor/cytotoxic (OKT8+) T cells. The PHA stimulated culture supernatant from one of these patients failed to induce proliferation of a cytolytic continuous T cell line. Our data suggests that the underlying defect in these patients may be a failure in production of interleukins but not in the acquisition of IL-2 receptors.