Anti-lymphocyte antibodies in patients with the acquired immune deficiency syndrome

Human lymphotropic retroviruses lymphadenopathy-associated virus/human T lymphoma virus III have been recently implicated in the pathogenesis of the acquired immune deficiency syndrome (AIDS). The mechanisms leading to the complex immune deregulations of this disease, however, are still largely unknown. To investigate the possible presence of anti-lymphocyte antibodies, lymphocytes from a normal donor were incubated with serum samples from patients with AIDS. Substantial increases of up to 75 percent in the number of surface immunoglobulin-positive lymphocytes resulted from incubation with serum of patients with AIDS and AIDS-related complex but not with serum of patients with non-AIDS-related diseases or of normal control subjects. Monoclonal antibodies to OKT11, OKT4, and OKT8 in conjunction with a double-labeling technique were then used to identify the type of surface immunoglobulin-positive lymphocytes. These experiments showed that binding of immunoglobulins to lymphocytes did not occur at random but was directed against OKT4- or OKT11-positive cells whereas OKT8-positive cells showed no detectable reactivity. The results of these studies indicate that patients with AIDS and AIDS-related complex have circulating antibodies capable of reacting selectively with a population of T cells that is predominantly composed of helper cells and does not include suppressor cells. The augmentation of surface immunoglobulin-positive lymphocytes in the patients studied consistently paralleled the marked decreases of the helper/suppressor cell ratios and the presence of circulating anti-human T lymphoma virus III antibodies. Binding of antibodies to the surface of helper T cells may be a determining event in the pathogenesis of this disease.