Balance between activation and regulation of HIV-specific CD8+ T-cell response after modified vaccinia Ankara B therapeutic vaccination.

Autor: Rallón N; aIIS-Fundación Jiménez Díaz, UAM, Madrid bHospital Universitario Rey Juan Carlos, Móstoles cIrsicaixa/HIVACAT, Autonomous University of Barcelona, Hospital Germans Trias i Pujol, Badalona dHospital General Universitario Gregorio Marañon, Madrid eHospital Clinic, Barcelona fCentro Nacional de Investigaciones Cardiovasculares CNIC gCentro Nacional de Biotecnologia, Madrid hInstitució Catalana de Recerca i Estudis Avancats (ICREA), Barcelona iUniversity of Vic and Central Catalonia, Vic, Spain., Mothe B, Lopez Bernaldo de Quiros JC, Plana M, Ligos JM, Montoya M, Muñoz-Fernández MA, Esteban M, Garcia F, Brander C, Benito JM
Jazyk: angličtina
Zdroj: AIDS (London, England) [AIDS] 2016 Feb 20; Vol. 30 (4), pp. 553-62.
DOI: 10.1097/QAD.0000000000000966
Abstrakt: Background: The causes of HIV-vaccines failure are poorly understood. Therapeutic vaccination with modified vaccinia Ankara (MVA)-B in HIV-1-infected individuals did not control the virus upon analytical treatment interruption (ATI). We investigated whether the functional characteristics of HIV-specific CD8 T-cell responses stimulated by this vaccine, and the level of exhaustion of these cells might explain these results.
Methods: Twenty-one HIV-1 chronically infected patients on combination antiretroviral therapy, included in the therapeutic vaccine trial RISVAC03, were studied: 13 immunized and eight controls. Functional characteristics, cytotoxic potential and exhaustion of HIV-specific CD8 T cells, were evaluated by polychromatic flow cytometry. Differences between groups were tested using nonparametric tests.
Results: MVA-B vaccine induced an increase in HIV-specific CD8 T-cell response, but also increased their levels of exhaustion. At week 18 (following three immunizations) the level of response increased with respect to baseline (P = 0.02). A significant increase at weeks 18 and 24 (ATI) in granzyme B content was also observed. Interestingly, an increase in expression of exhaustion markers was found at weeks 18 (P = 0.006) and 24 (P = 0.01). However, there was no significant change in the functional profile of vaccine-induced CD8 cells. At week 36, in parallel to the rebound of plasma viremia after 12 weeks ATI, a significant increase in the level of CD8 response, in granzyme B content and in exhaustion markers expression, was observed in both groups.
Conclusion: We show that therapeutic vaccination with MVA-B tilts the balance between activation and regulation of the response of HIV-specific CD8 T cells towards regulation, which impacts on the viral rebound after ATI.
Databáze: MEDLINE