Vaccination with irradiated Ancylostoma caninum third stage larvae induces a Th2 protective response in dogs.
While X-irradiated live parasites are not an acceptable proposition for human vaccination, they offer a ready experimental system to explore mechanisms by which immunity against hookworm infection may be induced in humans. As such, we sought to further elucidate the details of this highly protective immune response induced by the irradiated vaccine in canids, with special emphasis on the cellular aspects of the response. Vaccination with irradiated L3 induced high production of antibodies and strong PBMCs proliferation to crude L3 antigen preparation. Elevated IL-4 production was also observed in vaccinated dogs, especially in relation to IFN-gamma production (IL-4/IFN-gamma ratio). Serum from vaccinated animals inhibited penetration of L3 through canine skin in vitro by 60%. Finally, vaccinated animals had a strong antibody response to ASP-2, a promising vaccine antigen that is an excretory-secretory product of L3. These results add further support the idea that the Th2 immune response is required to generate protective immunity against hookworm larvae and that ES molecules released during this developmental stage are likely targets of this response.
Fujiwara
Ricardo T
RT
Department of Microbiology and Tropical Medicine, The George Washington University, 2300 Eye Street, Ross Hall Room 727, Medical Center, Washington, DC 20037, USA. mtmrtf@gwumc.edu
Loukas
Alex
A
Mendez
Susana
S
Williamson
Angela L
AL
Bueno
Lilian L
LL
Wang
Yan
Y
Samuel
Andre
A
Zhan
Bin
B
Bottazzi
Maria Elena
ME
Hotez
Peter J
PJ
Bethony
Jeffrey M
JM
D000722:Ancylostoma / Q000235:genetics / Q000276:immunology* / Q000528:radiation effects*; D000724:Ancylostomiasis / Q000276:immunology / Q000469:parasitology / Q000517:prevention & control / Q000662:veterinary*; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D000947:Antigens, Helminth / Q000276:immunology*; D004283:Dog Diseases / Q000276:immunology / Q000469:parasitology / Q000517:prevention & control; D004285:Dogs; D007814:Larva / Q000276:immunology / Q000528:radiation effects; D008666:Metalloendopeptidases / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D018418:Th2 Cells / Q000276:immunology; D014611:Vaccination
D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D008666:Metalloendopeptidases