Vaccination against Ostertagia ostertagi with subfractions of the protective ES-thiol fraction.
Previous vaccination trials against Ostertagia ostertagi in cattle have demonstrated the protective capacity of a protein fraction termed ES-thiol, which is enriched for activation-associated secreted proteins (ASPs) and cysteine proteases. In this study, ES-thiol was subfractionated through Q-Sepharose anion exchange chromatography to determine whether the ASPs and/or the cysteine proteases are responsible for the induced protection. Calves (seven/group) were immunized three times intramuscularly with 100 microg of ES-thiol or equivalent amounts of an ASP-enriched fraction, a cysteine protease-enriched fraction or a rest fraction, with QuilA adjuvant. A negative control group only received QuilA. After the final immunization the animals were challenged with a trickle infection of 25,000 infectious L3 larvae (1000 L3/day; 5 days/week). During a 2-month period the geometric mean cumulative faecal egg count (FEC) of the ES-thiol group was reduced by 62% compared to the QuilA control group (P<0.05). Groups injected with the ASP-enriched, the cysteine protease-enriched and the rest fraction demonstrated a reduction in cumulative FEC of 74, 80 and 70%, respectively (P<0.01). Although no significant reductions in worm burdens were observed, adult male and female worms were significantly smaller in all vaccinated groups (P<0.05), except for male worms from the ES-thiol group. These results suggest the protective capacity of ASPs and the presence of other protective antigens in the ES-thiol fraction.
Meyvis
Y
Y
Laboratory of Parasitology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium. yves.meyvis@ugent.be
Geldhof
P
P
Gevaert
K
K
Timmerman
E
E
Vercruysse
J
J
Claerebout
E
E
D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D000947:Antigens, Helminth / Q000276:immunology*; D002417:Cattle; D002418:Cattle Diseases / Q000469:parasitology / Q000517:prevention & control*; D005243:Feces / Q000469:parasitology; D005260:Female; D015801:Helminth Proteins / Q000276:immunology*; D007814:Larva; D010028:Ostertagia / Q000276:immunology*; D010029:Ostertagiasis / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D013997:Time Factors; D014611:Vaccination / Q000662:veterinary*; D014612:Vaccines / Q000276:immunology*
D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D015801:Helminth Proteins; D014612:Vaccines; C097418:excretory-secretory protein, Ostertagia