Restoration of impaired B- and T-lymphocyte subsets and functions in vitro by isoprinosine in prodromal homosexuals and AIDS patients.

Functional and phenotypical parameters demonstrated significant aberrations in both prodromal males and patients with the acquired immune deficiency syndrome (AIDS). Impaired B-cell functions as quantitated by Staphylococcus aureas Cowan Strain I (SAC) and pokeweed mitogen (PWM)-induced blastogenesis, intracytoplasmic immunoglobulins and spontaneous immunoglobulin were associated with a significant decrease in Leu3+ cells but unrelated to Leu2+ lymphocytes. The functional subsets of the latter were further defined by monoclonal antibodies (Leu8 and HLA-DR) applying dual color flow cytometry. Activated and effector-suppressor subsets with the phenotypes Leu2+ HLA-DR+ and Leu2+ Leu8- were elevated while both subsets of helper and suppressor-inducing helper lymphocytes, Leu3+ Leu8- and Leu3+ Leu8+, were depressed. These data demonstrated a broad spectrum of dysfunction involving all 3 stages of B-cell development in AIDS as well as possible defects in the feedback suppressor loop which regulates both the helper and suppressor T-lymphocyte system and B-cell functions. While in vitro incubation with isoprinosine had no modulative effect on SAC-induced blastogenesis (resting B-cell activities), it did modulate both PHA, PWM-induced transformation and the spontaneous secretion of immunoglobulins (partially and fully activated B-cell activities). In co-incubation with PWM, isoprinosine augmented the expression of inducer cells for helper functions while enhancing to normal level the number of suppressor-inducing helper cells. In addition, it reduced activated and effector-suppressor cells to near normal range in the PBL of high risk homosexuals. Only marginal modulation, however, was observed in suppressor subsets of AIDS subjects. This interference with the defective feedback loop may account for the selective clinical and immunoregulatory actions of this drug.