DNA and virus particle vaccination protects against acquisition and confers control of viremia upon heterologous simian immunodeficiency virus challenge.
We have previously shown that macaques vaccinated with DNA vectors expressing SIVmac239 antigens developed potent immune responses able to reduce viremia upon high-dose SIVmac251 challenge. To further improve vaccine-induced immunity and protection, we combined the SIVmac239 DNA vaccine with protein immunization using inactivated SIVmac239 viral particles as protein source. Twenty-six weeks after the last vaccination, the animals were challenged intrarectally at weekly intervals with a titrated dose of the heterologous SIVsmE660. Two of DNA-protein coimmunized macaques did not become infected after 14 challenges, but all controls were infected by 11 challenges. Vaccinated macaques showed modest protection from SIVsmE660 acquisition compared with naïve controls (P = 0.050; stratified for TRIM5α genotype). Vaccinees had significantly lower peak (1.6 log, P = 0.0048) and chronic phase viremia (P = 0.044), with 73% of the vaccinees suppressing viral replication to levels below assay detection during the 40-wk follow-up. Vaccine-induced immune responses associated significantly with virus control: binding antibody titers and the presence of rectal IgG to SIVsmE660 Env correlated with delayed SIVsmE660 acquisition; SIV-specific cytotoxic T cells, prechallenge CD4(+) effector memory, and postchallenge CD8(+) transitional memory cells correlated with control of viremia. Thus, SIVmac239 DNA and protein-based vaccine protocols were able to achieve high, persistent, broad, and effective cellular and humoral immune responses able to delay heterologous SIVsmE660 infection and to provide long-term control of viremia. These studies support a role of DNA and protein-based vaccines for development of an efficacious HIV/AIDS vaccine.
Human Retrovirus Section, Vaccine Branch, Center for Cancer Research, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA.
Vainav
V
Patel
Rashmi
R
Jalah
Viraj
V
Kulkarni
Antonio
A
Valentin
Margherita
M
Rosati
Candido
C
Alicea
Agneta
A
von Gegerfelt
Wensheng
W
Huang
Yongjun
Y
Guan
Brandon F
BF
Keele
Julian W
JW
Bess
Michael
M
Piatak
Jeffrey D
JD
Lifson
William T
WT
Williams
Xiaoying
X
Shen
Georgia D
GD
Tomaras
Rama R
RR
Amara
Harriet L
HL
Robinson
Welkin
W
Johnson
Kate E
KE
Broderick
Niranjan Y
NY
Sardesai
David J
DJ
Venzon
Vanessa M
VM
Hirsch
Barbara K
BK
Felber
George N
GN
Pavlakis
D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis; D004279:DNA, Viral / Q000008:administration & dosage / Q000276:immunology*; D007111:Immunity, Cellular; D007074:Immunoglobulin G / Q000276:immunology; D008253:Macaca mulatta; D012007:Rectum / Q000276:immunology; D016097:Simian Acquired Immunodeficiency Syndrome / Q000191:economics / Q000276:immunology* / Q000821:virology; D015302:Simian Immunodeficiency Virus / Q000276:immunology*; D019562:Viral Load; D014765:Viral Vaccines / Q000008:administration & dosage / Q000276:immunology*; D014766:Viremia / Q000517:prevention & control*; D014771:Virion / Q000276:immunology*
D000914:Antibodies, Viral; D004279:DNA, Viral; D007074:Immunoglobulin G; D014765:Viral Vaccines