title: HIV infection deregulates the balance between regulatory T cells and IL-2-producing CD4 T cells by decreasing the expression of the IL-2 receptor in Treg.
abstract: Indexation of regulatory T cells (Treg) to the number of activated T cells constitutes a homeostatic mechanism ensuring that T-cell expansion remains under control. However, immune hyperactivation observed in HIV-infected patients suggests a possible dysfunction of this mechanism. Here we show that the Treg/IL-2-producing cells' balance is deeply disturbed in viremic HIV-infected patients. We found a lower expression of IL-2 receptor alpha on Treg from viremic patients. We confirmed in vitro that HIV infection of Treg downregulates IL-2 receptor alpha and phosphorylated STAT5. Our results argue for an impaired capacity of Treg to sense the expansion of activated T cells in HIV-infected patients that could contribute to the immune deregulation.
authors.affiliation: *Laboratorio de Inmunovirología, Unidad clínica de Enfermedades Infecciosas, Microbiología y Medicina Preventiva, Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain; †Laboratorio de InmunoBiología Molecular, Hospital General Universitario Gregorio Marañón and Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; and ‡Centro Investigación Biomédica en Red, Bioingeniería, Biomateriales y Nanomedicina, Madrid, Spain.
authors.forename: Gema
authors.initials: G
authors.lastname: Méndez-Lagares
authors.forename: Didiana
authors.initials: D
authors.lastname: Jaramillo-Ruiz
authors.forename: Marjorie
authors.initials: M
authors.lastname: Pion
authors.forename: Manuel
authors.initials: M
authors.lastname: Leal
authors.forename: M A
authors.initials: MA
authors.lastname: Muñoz-Fernández
authors.forename: Yolanda M
authors.initials: YM
authors.lastname: Pacheco
authors.forename: Rafael
authors.initials: R
authors.lastname: Correa-Rocha
mesh_terms: D000328:Adult; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D003430:Cross-Sectional Studies; D020869:Gene Expression Profiling; D015658:HIV Infections / Q000276:immunology*; D006801:Humans; D007376:Interleukin-2 / Q000378:metabolism*; D008297:Male; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis*; D050799:STAT5 Transcription Factor / Q000096:biosynthesis; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D007376:Interleukin-2; D015375:Receptors, Interleukin-2; D050799:STAT5 Transcription Factor