Brugia malayi: comparison of protective immune responses induced by Bm-alt-2 DNA, recombinant Bm-ALT-2 protein and prime-boost vaccine regimens in a jird model.
Immunization of jirds with Bm-alt-2 elicited partial protection against challenge infection with the filarial parasite Brugia malayi. In this study, we initially compared the protective immune responses elicited following immunization with recombinant Bm-ALT-2 protein regimen and Bm-alt-2 DNA regimen. These studies showed that protein vaccination conferred approximately 75% protection compared to DNA vaccination that conferred only 57% protection. Analysis of the protective immune responses showed that the protein immunization promoted a Th2-biased response with an increase in IL-4, IL-5 and IgG1 responses, whereas, the DNA vaccine promoted a Th1-biased response with profound IFN-gamma and IgG2a responses. Since protein vaccination gave better results than DNA vaccination, we then wanted to evaluate whether a prime-boost vaccination that combined DNA prime and protein boost will significantly increase the protective responses induced by the protein vaccine. Our results suggest that prime-boost vaccination had no added advantage and was comparatively less effective (64% protection) than the Bm-ALT-2 protein alone vaccination. Prime boost vaccination generated mixed Th1/Th2 responses with a slightly diminished Th2 responses compared to protein vaccination. Thus, our results suggest that Bm-ALT-2 protein vaccination regimen may be slightly better than prime-boost vaccine regimen and the mechanism of protection appears to be largely mediated by a Th2-biased response.
Thirugnanam
Sivasakthivel
S
Centre for Biotechnology, Anna University, Chennai 600 025, India.
Pandiaraja
Pandurangan
P
Ramaswamy
Kalyanasundaram
K
Murugan
Vadivel
V
Gnanasekar
Munirathinam
M
Nandakumar
Krithika
K
Reddy
Maryada Venkata Rami
MV
Kaliraj
Perumal
P
D000818:Animals; D000909:Antibodies, Helminth / Q000096:biosynthesis* / Q000097:blood; D000947:Antigens, Helminth / Q000235:genetics / Q000276:immunology*; D017178:Brugia malayi / Q000276:immunology*; D016207:Cytokines / Q000096:biosynthesis / Q000235:genetics; D018509:DNA, Helminth / Q000276:immunology; D015194:Diffusion Chambers, Culture; D004195:Disease Models, Animal; D004605:Elephantiasis, Filarial / Q000517:prevention & control*; D005849:Gerbillinae; D015801:Helminth Proteins / Q000235:genetics / Q000276:immunology*; D007111:Immunity, Cellular; D007114:Immunization / Q000379:methods; D008213:Lymphocyte Activation; D008297:Male; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology; D014612:Vaccines / Q000276:immunology*; D019444:Vaccines, DNA / Q000276:immunology; D014614:Vaccines, Synthetic / Q000276:immunology
C521555:ALT-2 protein, Brugia malayi; D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D016207:Cytokines; D018509:DNA, Helminth; D015801:Helminth Proteins; D011994:Recombinant Proteins; D014612:Vaccines; D019444:Vaccines, DNA; D014614:Vaccines, Synthetic