CD8+ lymphocyte phenotype and cytokine production in long‐term non‐progressor and in progressor patients with HIV‐1 infection

• Published in: Clinical and experimental immunology Vol. 105; no. 2; pp. 220 - 224
• Main Authors: ZANUSSI, S., SIMONELLI, C., D'ANDREA, M., CAFFAU, C., CLERICI, M., TIRELLI, U., DE PAOLI, P.
• Format: Journal Article
• Language: English
• Published: Oxford BSL Blackwell Science Ltd 01.08.1996; Blackwell Science Inc
• Subjects: Acquired Immunodeficiency Syndrome - immunology; Adult; AIDS/HIV; CD28; CD28 Antigens - analysis; CD8+ lymphocytes; CD8-Positive T-Lymphocytes - immunology; CD95; Cytokines - biosynthesis; fas Receptor - analysis; Female; HIV-1; HIV‐1 non‐progression; Humans; Immunophenotyping; Male; Rapid Publications
• ISSN: 0009-9104; 1365-2249
• DOI: 10.1046/j.1365-2249.1996.d01-746.x

In most HIV‐1‐infected patients, clinical and immunological progression develops within a few years. Few infected people, termed long‐term non‐progressors (LTNP), remain healthy and immunologically stable for a long time. The factors governing the maintenance of this condition are not well known, but it is conceivable that CD8+ lymphocytes, cells that play a central role in controlling in vitro HIV replication, may have a part in vivo in this process. The aim of this study was to characterize the phenotypic profile and the cytokine production of CD8+ cells in a group of LTNP patients who had stable CD4+ cell counts (>500/mm3) for at least 7 years. Their CD8+ absolute numbers were similar to a control group composed of HIV‐1+ patients who have a progressive decline of their CD4+ cell counts. However, our multiparameter immunofluorescence studies show that a clinical and immunologically stable condition is associated with the presence of a CD28+, CD95 strongly positive CD8+ population, while disease progression is marked by the CD28−CD95+CD8+ subset. Purified CD8+ cells from LTNP retain their ability to produce IL‐2, interferon‐gamma (IFN‐γ) and, to a lesser degree, to produce IL‐10 and IL‐4. In contrast, CD8+ cells from progressors are unable to secrete IL‐2 and IL‐10. Although CD8+ cytokine profile does not fit with the proposed T helper (Th)1/Th2 switch in progressive HIV infection, LTNP CD8+ T cells maintain their capacity to produce IL‐2 and IL‐10 (Th0‐like), a pattern very similar to that observed in normal HIV healthy controls. We suggest that CD8+ cells expressing CD28, CD95 and having a Th0‐like profile may be considered to be associated with long‐term survival.