Use of RT-defective HIV virions: new tool to evaluate specific response in chronic asymptomatic HIV-infected individuals

• Published in: PloS one 2013-03, Vol.8 (3), p.e58927
• Main Authors: Guardo, Alberto Crespo, Alvarez-Fernández, Carmen, Arberas, Hodei, García-Pérez, Javier, García, Felipe, Bargalló, Manuel Enric, Maleno, María José, Gatell, José María, Mothe, Beatriz, Alcami, José, Sánchez-Palomino, Sonsoles, Plana, Montserrat
• Format: Article
• Language: English
• Subjects: Acquired immune deficiency syndrome; Adult; AIDS; AIDS vaccines; Alleles; Asymptomatic Diseases; Biology; CD38 antigen; CD4 antigen; CD4-Positive T-Lymphocytes - immunology; CD4-Positive T-Lymphocytes - virology; CD69 antigen; CD8-Positive T-Lymphocytes - immunology; CD8-Positive T-Lymphocytes - virology; Cell activation; Clinical trials; Cryopreservation; Cytokines; Cytometry; Defects; Development and progression; Envelopes; Enzyme-linked immunosorbent assay; Female; Flow cytometry; Gag protein; Gene frequency; Histocompatibility antigen HLA; HIV; HIV (Viruses); HIV infections; HIV Infections - immunology; HIV patients; HIV Reverse Transcriptase - genetics; HIV Reverse Transcriptase - metabolism; HIV tests; HIV-1 - enzymology; HIV-1 - immunology; HIV-1 - physiology; Human immunodeficiency virus; Humans; Immunogenicity; Immunologia; Immunology; Interferon; Leukocytes, Mononuclear - immunology; Leukocytes, Mononuclear - virology; Low cost; Lymphocytes; Lymphocytes T; Male; Markers; Medicine; Microbial Viability - immunology; Middle Aged; Nef protein; Peptides; Peripheral blood mononuclear cells; Prototypes; Reagents; Safety; Sex Characteristics; Surface activation; T cell receptors; T cells; Time Factors; Vaccines; Vacunes antivíriques; VIH (Virus); Viral Load - immunology; Viral vaccines; Viral Vaccines - adverse effects; Viral Vaccines - immunology; Virion - enzymology; Virion - immunology; Virion - physiology; Virions; Viruses; Young Adult; γ-Interferon
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0058927

Generation of new reagents that can be used to screen or monitor HIV-1-specific responses constituted an interesting field in the development of HIV vaccines to improve their efficacy. We have evaluated the specific T cell response against different types of NL4-3 virions (including NL4-3 aldrithiol-2 treated, NL4-3/ΔRT and R5 envelopes: NL4-3/ΔRT/ΔEnv[AC10] and NL4-3/ΔRT/ΔEnv[Bal]) and against pools of overlapping peptides (15 mer) encompassing the HIV-1 Gag and Nef regions. Cryopreserved PBMC from a subset of 69 chronic asymptomatic HIV positive individuals have been employed using different techniques including IFN-γ ELISPOT assay, surface activation markers and intracellular cytokine staining (ICS) by flow cytometry. The differential response obtained against NL4-3 aldrithiol-2 treated and NL4-3/ΔRT virions (25% vs 55%, respectively) allow us to divide the population in three groups: "full-responders" (positive response against both viral particles), "partial-responders" (positive response only against NL4-3/ΔRT virions) and "non-responders" (negative responses). There was no difference between X4 and R5 envelopes. The magnitude of the total responses was higher against NL4-3/ΔRT and was positively correlated with gender and inverse correlated with viral load. On the contrary CD4+ T cell count was not associated with this response. In any case responses to the viruses tended to be lower in magnitude than those detected by the overlapping peptides tested. Finally we have found an increased frequency of HLA-B27 allele (23% vs 9%) and a significant reduction in some activation markers (CD69 and CD38) on T cells surface in responders vs non-responders individuals. In summary these virions could be considered as alternative and useful reagents for screening HIV-1-specific T cell responses in HIV exposed uninfected people, HIV infected patients and to assess immunogenicity of new prototypes both in vitro and in vaccine trials, by a feasible, simply, effective and low cost assay.