In vitro immunologic and virologic effects of interleukin 15 on peripheral blood mononuclear cells from normal donors and human immunodeficiency virus type 1-infected patients

• Published in: Clinical and diagnostic laboratory immunology Vol. 4; no. 1; pp. 43 - 48
• Main Authors: Lucey, D R, Pinto, L A, Bethke, F R, Rusnak, J, Melcher, G P, Hashemi, F N, Landay, A L, Kessler, H A, Paxton, R J, Grabstein, K, Shearer, G M
• Format: Journal Article
• Language: English
• Published: United States 01-01-1997
• Subjects: AIDS/HIV; Cells, Cultured; HIV Infections - immunology; HIV Infections - therapy; HIV Infections - virology; HIV-1 - drug effects; HIV-1 - isolation & purification; human immunodeficiency virus 1; Humans; Interferon-gamma - analysis; Interferon-gamma - pharmacology; Interleukin-15 - pharmacology; Interleukin-2 - analysis; Interleukin-2 - pharmacology; Killer Cells, Lymphokine-Activated - drug effects; Leukocytes, Mononuclear - drug effects; Lymphocyte Activation - drug effects
• ISSN: 1071-412X; 1098-6588
• DOI: 10.1128/CDLI.4.1.43-48.1997

Interleukin 15 (IL-15) is a cytokine that shares receptor subunits and functional activity, such as T-cell and B-cell stimulation, with IL-2. The effect of IL-2 on immune function and human immunodeficiency virus (HIV) viral load in HIV-infected patients is being actively studied. Thus, we examined how IL-15 compares with IL-2 in several in vitro immunologic and virologic assays in order to explore whether a rationale exists for pursuing initial clinical therapeutic trials with IL-15. The effects of IL-15 on induction of lymphokine-activated killer (LAK) cells, gamma interferon (IFN-gamma) production from HIV-positive peripheral blood mononuclear cells (PBMCs), and HIV production from PBMCs were studied. Induction of LAK cells by IL-15 was found in eight of eight HIV-positive donors. Incubation of PBMCs from some donors with IL-15 (1, 10, 50, and 100 ng/ml) induced production of IFN-gamma. The effect of IL-15 was compared with that of IL-2 on HIV replication in PBMCs from five HIV-positive patients and four HIV-negative donors whose PBMCs were infected in vitro with HIV. Levels of HIV p24 antigen were moderately lower in the presence of 10 ng of IL-15 per ml than with 10 ng of IL-2 per ml, but they were similar for 100 and 500 ng of each cytokine per ml. In summary, IL-15 can induce LAK cell activity in HIV-seropositive patients and can stimulate IFN-gamma production from PBMCs of some donors. IL-15 stimulates levels of HIV production from PBMCs which are similar to or moderately lower than those obtained with IL-2, depending on cytokine concentration.