Vaccination against Ostertagia ostertagi with subfractions of the protective ES-thiol fraction

Abstract

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 mg 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. #

Granule Exocytosis of Granulysin and Granzyme B as a Potential Key Mechanism in Vaccine-Induced Immunity in Cattle against the Nematode Ostertagia ostertagi

“…1A. The group of animals vaccinated with the ASP-based vaccine in combination with QuilA as an adjuvant showed a significant (P Ͻ 0.05) reduction in the cumulative fecal egg count (cumEPG) of 59%, which is consistent with previous trials in which a similar reduction in the cumulative number of EPG of feces was observed (14,16). Although it was not significant, there was also a small reduction in the total number of worms counted (20%) and in the average length of female worms (3%).…”

“…Helminth-naïve calves were infected with 200,000 O. ostertagi infective larvae (L3) and euthanized 3 weeks later to collect adult worms from the abomasum. O. ostertagi adults were cultured, and ES proteins were collected from the culture supernatant as previously described (16). The ASP subfraction was purified from total adult ES by thiol Sepharose chromatography, followed by anion-exchange chromatography as previously described (16).…”

“…O. ostertagi adults were cultured, and ES proteins were collected from the culture supernatant as previously described (16). The ASP subfraction was purified from total adult ES by thiol Sepharose chromatography, followed by anion-exchange chromatography as previously described (16). The protein profile of the material obtained was checked by separation by 10% sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under reducing/ denaturing conditions and visualized by Coomassie blue staining.…”

“…After the final immunization, the animals were challenged with a trickle infection of 30,000 infective L3 larvae (1,000 L3 larvae/day for 30 days, 5 days a week, for a period of 6 weeks). Three weeks after the last challenge infection, all animals were sacrificed and parasitological parameters (i.e., fecal egg counts, worm counts, and worm lengths) were analyzed as described in previous trials (13,14,16).…”

Gender-enriched transcription of activation associated secreted proteins in Ostertagia ostertagi

“…They are of general interest as they have shown their protective capacity in multiple vaccination trials against Ancylostoma spp., H. contortus and O. ostertagi (Schallig et al, 1997a;Ghosh and Hotez, 1999;Geldhof et al, 2002Geldhof et al, , 2004Goud et al, 2004;Meyvis et al, 2007). Three types of ASP proteins have been identified in nematodes: long ASP proteins composed of two distinct but related domains and short ASP molecules that show similarity to either the C-terminal or the N-terminal domain of the double-domain ASP.…”