A heterologous prime-boost vaccination regime using DNA and a vaccinia virus, both expressing GRA4, induced protective immunity against Toxoplasma gondii infection in mice.
SUMMARYThe dense granule antigen 4 (GRA4) is known as an immundominant antigen of Toxoplasma gondii and, therefore, is considered as a vaccine candidate. For further evaluation of its vaccine effect, a recombinant plasmid and vaccinia virus, both expressing GRA4, were constructed, and a heterologous prime-boost vaccination regime was performed in a mouse model. The mice immunized with the heterologous prime-boost vaccination regime showed a high level of specific antibody response against GRA4 and a significantly high level of gamma interferon (IFN-gamma) production and survived completely against a subsequent challenge infection with a lethal dose of T. gondii. In addition, the formation of cysts was inhibited in the mice vaccinated with the heterologous prime-boost vaccination regime. These results demonstrate that the heterologous prime-boost vaccination regime using DNA and a vaccinia virus, both expressing GRA4, could induce both humoral and cellular immune responses and provide effective protection against lethal acute and chronic T. gondii infections in mice.
Zhang
G
G
National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan.
Huong
V T T
VT
Battur
B
B
Zhou
J
J
Zhang
H
H
Liao
M
M
Kawase
O
O
Lee
E G
EG
Dautu
G
G
Igarashi
M
M
Nishikawa
Y
Y
Xuan
X
X
D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000917:Antibody Formation / Q000276:immunology; D001921:Brain / Q000469:parasitology; D002522:Chlorocebus aethiops; D005260:Female; D007111:Immunity, Cellular / Q000276:immunology; D007371:Interferon-gamma / Q000032:analysis; D051379:Mice; D008810:Mice, Inbred C57BL; D015800:Protozoan Proteins / Q000235:genetics / Q000276:immunology*; D016052:Protozoan Vaccines / Q000276:immunology*; D013997:Time Factors; D014122:Toxoplasma / Q000235:genetics / Q000276:immunology*; D014123:Toxoplasmosis / Q000276:immunology* / Q000517:prevention & control*; D019444:Vaccines, DNA / Q000276:immunology*; D014616:Vaccinia virus / Q000235:genetics*; D014709:Vero Cells
D000913:Antibodies, Protozoan; C079248:GRA4 protein, Toxoplasma gondii; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; D019444:Vaccines, DNA; D007371:Interferon-gamma