In:
The Journal of Immunology, The American Association of Immunologists, Vol. 188, No. 10 ( 2012-05-15), p. 5166-5176
Kurzfassung:
The Thai HIV phase III prime/boost vaccine trial (RV144) using ALVAC-HIV (vCP1521) and AIDSVAX B/E was, to our knowledge, the first to demonstrate acquisition efficacy. Vaccine-induced, cell-mediated immune responses were assessed. T cell epitope mapping studies using IFN-γ ELISPOT was performed on PBMCs from HIV-1–uninfected vaccine (n = 61) and placebo (n = 10) recipients using HIV-1 Env peptides. Positive responses were measured in 25 (41%) vaccinees and were predominantly CD4+ T cell-mediated. Responses were targeted within the HIV Env region, with 15 of 25 (60%) of vaccinees recognizing peptides derived from the V2 region of HIV-1 Env, which includes the α4β7 integrin binding site. Intracellular cytokine staining confirmed that Env responses predominated (19 of 30; 63% of vaccine recipients) and were mediated by polyfunctional effector memory CD4+ T cells, with the majority of responders producing both IL-2 and IFN-γ (12 of 19; 63%). HIV Env Ab titers were higher in subjects with IL-2 compared with those without IL-2–secreting HIV Env-specific effector memory T cells. Proliferation assays revealed that HIV Ag-specific T cells were CD4+, with the majority (80%) expressing CD107a. HIV-specific T cell lines obtained from vaccine recipients confirmed V2 specificity, polyfunctionality, and functional cytolytic capacity. Although the RV144 T cell responses were modest in frequency compared with humoral immune responses, the CD4+ T cell response was directed to HIV-1 Env and more particularly the V2 region.
Materialart:
Online-Ressource
ISSN:
0022-1767
,
1550-6606
DOI:
10.4049/jimmunol.1102756
Sprache:
Englisch
Verlag:
The American Association of Immunologists
Publikationsdatum:
2012
ZDB Id:
1475085-5