Sakaida H, Murakami T, Kawamata S, Hattori T, Uchiyama T. V3 loop of human immunodeficiency virus type 1 suppresses interleukin 2-induced T cell growth.
AIDS Res Hum Retroviruses 1997;
13:151-9. [PMID:
9007200 DOI:
10.1089/aid.1997.13.151]
[Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
We tested the effect of three linear or two loop peptides derived from the V3 region of the HTLV-III BH10 clone or the SF2 strain of human immunodeficiency virus type 1 on IL-2-driven T cell proliferation. V3-BH10, which consists of 42 amino acids and has a loop structure, suppressed IL-2-driven proliferation of all IL-2-dependent cells [Kit225, ED-40515(+), KT-3, 7-day PHA-blasts, and fresh peripheral blood mononuclear cells] tested, whereas it did not suppress the cell growth of IL-2-independent cell lines (Hut102, Molt-4, and Jurkat). This suppressive effect was also seen in IL-2-driven cell growth of CD8-positive lymphocytes purified from 7-day PHA-blasts, indicating that CD4 molecules were not required for the suppression. The treatment with anti-V3 loop monoclonal antibody (902 antibody) completely abolished the suppressive effect of V3-BH10. In addition, V3-BH10 generated the arrest of Kit225 cells and also purified CD8-positive lymphocytes in G1 phase in the presence of IL-2. Neither chromatin condensation nor DNA fragmentation was detected in Kit225 cells cultured with V3-BH10 and IL-2. V3-BH10 neither blocked radiolabeled IL-2 binding to IL-2 receptors nor affected tyrosyl phosphorylation of several cellular proteins (p120, p98, p96, p54, and p38), which is immediately induced by IL-2 stimulation. However, V3-BH10 enhanced IL-2-induced mRNA expression of c-fos but not c-myc or junB. Thus, the binding of V3 loop of gp120 to the cell surface molecule(s) appears to affect intracellular IL-2 signaling, which leads to the suppression of IL-2-induced T cell growth.
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