MVA-nef induces HIV-1-specific polyfunctional and proliferative T-cell responses revealed by the combination of short- and long-term immune assays.
Several vaccination trials are evaluating the modified vaccinia virus Ankara (MVA) as a delivery vector in various clinical settings. In this paper, we present the reevaluation of a therapeutic vaccination trial in human immunodeficiency virus (HIV)-1-infected individuals treated with highly active antiretroviral therapy using MVA-expressing HIV-1 nef. Immunogenicity of MVA-nef was assessed using multicolor flow cytometry. Vaccine-induced polyfunctionality and proliferative capacity, which are associated with nonprogressive HIV-1 infection, were detectable by combining two immune assays. By means of short-term polychromatic intracellular cytokine staining, we observed a significant increase in polyfunctional Nef-specific CD4 T cells expressing interferon-γ, interleukin (IL)-2 and CD154 after vaccination, whereas changes in the quality of CD8 T-cell response could not be observed. Only the additional use of a long-term polychromatic Carboxyfluorescein succinimidyl ester (CFSE)-based proliferation assay revealed vaccine-induced Nef-specific CD8, as well as CD4 T cells with proliferative capacity. The correlation between vaccine-induced IL-2 production by CD4 T cells and the increase in proliferating Nef-specific CD8 T cells suggests a causal link between these two functions. These results highlight the importance of combining sophisticated immunomonitoring tools to unravel concealed effects of immunological interventions and support the use of the poxvirus-derived MVA vector to stimulate highly functional HIV-1-specific T-cell responses. However, the clinical benefit of these functional T cells remains to be determined.
Kutscher
S
S
Institute of Virology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany. sarah.kutscher@helmholtz-muenchen.de
Allgayer
S
S
Dembek
C J
CJ
Bogner
J R
JR
Protzer
U
U
Goebel
F D
FD
Erfle
V
V
Cosma
A
A
D016915:AIDS Vaccines / Q000276:immunology*; D023241:Antiretroviral Therapy, Highly Active; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D049109:Cell Proliferation; D005822:Genetic Vectors / Q000235:genetics; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1 / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007118:Immunoassay; D007371:Interferon-gamma / Q000378:metabolism; D008213:Lymphocyte Activation / Q000235:genetics / Q000276:immunology; D019444:Vaccines, DNA / Q000276:immunology; D014616:Vaccinia virus / Q000235:genetics; D054311:nef Gene Products, Human Immunodeficiency Virus / Q000235:genetics / Q000276:immunology
D016915:AIDS Vaccines; C483360:MVA-HIV-1 nef vaccine; D019444:Vaccines, DNA; D054311:nef Gene Products, Human Immunodeficiency Virus; C514837:nef protein, Human immunodeficiency virus 1; D007371:Interferon-gamma