Immunogenicity and protective efficacy of recombinant human T-cell leukemia/lymphoma virus type 1 NYVAC and naked DNA vaccine candidates in squirrel monkeys (Saimiri sciureus).
We assessed the immunogenicities and efficacies of two highly attenuated vaccinia virus-derived NYVAC vaccine candidates encoding the human T-cell leukemia/lymphoma virus type 1 (HTLV-1) env gene or both the env and gag genes in prime-boost pilot regimens in combination with naked DNA expressing the HTLV-1 envelope. Three inoculations of NYVAC HTLV-1 env at 0, 1, and 3 months followed by a single inoculation of DNA env at 9 months protected against intravenous challenge with HTLV-1-infected cells in one of three immunized squirrel monkeys. Furthermore, humoral and cell-mediated immune responses against HTLV-1 Env could be detected in this protected animal. However, priming the animal with a single dose of env DNA, followed by immunization with the NYVAC HTLV-1 gag and env vaccine at 6, 7, and 8 months, protected all three animals against challenge with HTLV-1-infected cells. With this protocol, antibodies against HTLV-1 Env and cell-mediated responses against Env and Gag could also be detected in the protected animals. Although the relative superiority of a DNA prime-NYVAC boost regimen over addition of the Gag component as an immunogen cannot be assessed directly, our findings nevertheless show that an HTLV-1 vaccine approach is feasible and deserves further study.
Kazanji
M
M
Laboratoire de Rétrovirologie, Institut Pasteur de la Guyane, 23 Av. Pasteur, Cayenne, French Guiana. mkazanji@pasteur-cayenne.fr
Tartaglia
J
J
Franchini
G
G
de Thoisy
B
B
Talarmin
A
A
Contamin
H
H
Gessain
A
A
de Thé
G
G
D000818:Animals; D015686:Gene Products, env / Q000276:immunology*; D015683:Gene Products, gag / Q000276:immunology*; D015368:Human T-lymphotropic virus 1 / Q000276:immunology*; D007114:Immunization; D008297:Male; D012453:Saimiri; D019444:Vaccines, DNA / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000276:immunology*; D014765:Viral Vaccines / Q000276:immunology*
D015686:Gene Products, env; D015683:Gene Products, gag; D019444:Vaccines, DNA; D014614:Vaccines, Synthetic; D014765:Viral Vaccines