Deficient in vitro anti-mycobacterial immunity despite successful long-term highly active antiretroviral therapy in HIV-infected patients with past history of tuberculosis infection or disease

• Published in: Clinical Immunology 2007-10, Vol.125 (1), p.60-66
• Main Authors: Mendonça, Marcelo, Tanji, Maury M, Silva, Léia C.R, Silveira, Guilherme G, Oliveira, Sérgio C, Duarte, Alberto J.S, Benard, Gil
• Format: Article
• Language: English
• Subjects: Adult; Allergy and Immunology; Antiretroviral Therapy, Highly Active; Biological and medical sciences; Cell Proliferation - drug effects; Enzyme-Linked Immunosorbent Assay; Female; Fundamental and applied biological sciences. Psychology; Fundamental immunology; General aspects; HAART; HIV; HIV Infections - drug therapy; HIV Infections - immunology; Human immunodeficiency virus; Humans; IFN-γ; Immunologic Memory; In Vitro Techniques; Interferon-gamma - biosynthesis; Interferon-gamma - drug effects; Leukocytes, Mononuclear - drug effects; Leukocytes, Mononuclear - immunology; Lymphocyte Activation; Lymphoproliferation; Male; Medical sciences; Middle Aged; Mycobacterium tuberculosis; Mycobacterium tuberculosis - immunology; PPD; Sarcoidosis. Granulomatous diseases of unproved etiology. Connective tissue diseases. Elastic tissue diseases. Vasculitis; Tuberculosis; Tuberculosis - immunology
• ISSN: 1521-6616; 1521-7035; 1365-2567
• DOI: 10.1016/j.clim.2007.06.002

Abstract We evaluated the anti- Mycobacterium tuberculosis (Mtb) immune responses of HIV patients after long-term successful HAART, presenting > 500 TCD4+ cells/μl, undetectable viral load, and past history of tuberculosis infection (HIV + PPD+, n = 14) or disease (HIV + CTB, n = 17). Their lymphoproliferative and IFN-γ responses were compared with those from HIV-uninfected controls either PPD+ (HIV − PPD+, n = 17) or with past history of pulmonary tuberculosis ( n = 15). Most HIV-infected patients presented normal PHA responses while responses to the Mtb recombinant polypeptides ESAT-6 and Ag85B were markedly reduced. Responses to a whole Mtb lysate (S-Mtb) in HIV + PPD+ patients were lower than in HIV − PPD+ controls, while in HIV + CTB patients these responses were similar to that of past-tuberculosis controls. Comparison between the two HIV groups also suggested better S-Mtb responses in those cured from tuberculosis. Thus, while immune responses to single Mtb proteins are depressed even after successful HAART, reactivity to S-Mtb is high, specially in those cured from tuberculosis, possibly as a result of the survival of higher numbers of mycobacteria-specific T cell clones during the immunosuppression phase, which may afford sufficient protection against new Mtb challenges.