title: Human immunodeficiency virus type 1 modulates telomerase activity in peripheral blood lymphocytes.
abstract: The effect of human immunodeficiency virus type 1 (HIV-1) on telomerase activity in peripheral blood lymphocytes (PBL) was examined. Telomerase is an enzyme that is involved in mechanisms that control cell life span and replicative potential. HIV-1 reduced telomerase activity in in vitro-infected PBL and impaired enzyme activation upon cell stimulation. Telomerase activity was significantly lower in PBL from 23 HIV-1-infected patients than in PBL from healthy donors and significantly increased during highly active antiretroviral therapy (HAART) in 10 patients who had both a virological and an immunological response and in 5 and 8 patients with a virological or an immunological response, respectively. Further analyses of fractionated cells revealed that telomerase activity increased mainly in CD4(+) lymphocytes. Overall, these findings demonstrate that HIV-1 infection down-modulates telomerase activity and suggest that both the HIV-1 decline and immunorestoration in response to HAART contribute to increased telomerase activity in CD4(+) lymphocytes.
authors.affiliation: Department of Oncology and Surgical Sciences, Section of Oncology, AIDS Reference Center, University of Padova, Padova, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Ballon
authors.forename: L
authors.initials: L
authors.lastname: Ometto
authors.forename: E
authors.initials: E
authors.lastname: Righetti
authors.forename: A M
authors.initials: AM
authors.lastname: Cattelan
authors.forename: S
authors.initials: S
authors.lastname: Masiero
authors.forename: M
authors.initials: M
authors.lastname: Zanchetta
authors.forename: L
authors.initials: L
authors.lastname: Chieco-Bianchi
authors.lastname: De Rossi A
mesh_terms: D023241:Antiretroviral Therapy, Highly Active; D015496:CD4-Positive T-Lymphocytes / Q000201:enzymology* / Q000276:immunology / Q000821:virology; D002478:Cells, Cultured; D004789:Enzyme Activation; D015658:HIV Infections / Q000188:drug therapy / Q000201:enzymology* / Q000276:immunology / Q000821:virology*; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000201:enzymology* / Q000821:virology*; D008213:Lymphocyte Activation; D010835:Phytohemagglutinins / Q000494:pharmacology; D012367:RNA, Viral / Q000097:blood; D019098:Telomerase / Q000378:metabolism*
chemical_list: D010835:Phytohemagglutinins; D012367:RNA, Viral; D019098:Telomerase