IMMUNOLOGICAL ANALYSIS OF PATIENTS WITH THALASSEMIA MAJOR AT RISK FOR AIDS

Abstract

Immunological analysis of 29 patients with thalassemia major has been undertaken to determine factors that might influence development of AIDS in cases of blood transfusion acquired Human Immunodefiency Virus, HIV, disease. Natural Killer, NK, activity against the K562 tumor target was very reduced in 72% (21 of 29) of cases initially and in 7 of 9 patients studied repeatedly. Augmentation in vitro with interferon α (800 I.U.) could be achieved in 11, or 52% of cases in contrast to 100% of controls. Of these 11, 8 showed boosting into low normal range. In addition some patients with normal endogenous NK could not be boosted in vitro. Of 25 patients studied for mononuclear proliferation in vitro 14 (56%) had reduced activation to mitogen. Study of Tymphocyte subpopulations by flow cytometry showed that few patients had percentages of T3+, T4+, or T8+ lymphocytes outside normal range although low normal T8+% was seen. However, 4 patients had reduced T4+/T8+ ratios with proportionately increased T8+% and borderline T4+%. All of these patients had serum antibodies to HIV. All 4 had very low endogenous NK that could not be augmented into normal range in vitro and 3 of 4 had poor proliferative response. Three patients with normal T4+/T8+ but poor function (1 had low T3+%) also had HIV antibodies. These data indicate probable high risk of AIDS in thalassemia patients with HIV disease and suggest that altered NK associated with thalassemia may potentiate this process since low NK and absence of interferon are found in both HIV antibody negative and positive patients.