Attempts to immunize sheep against Haemonchus contortus using a cocktail of recombinant proteases derived from the protective antigen, H‐gal‐GP

  title={Attempts to immunize sheep against Haemonchus contortus using a cocktail of recombinant proteases derived from the protective antigen, H‐gal‐GP},
  author={{\'E}lise Cachat and George F J Newlands and S E Ekoja and Hudson McAllister and W. David Smith},
  journal={Parasite Immunology},
The objective of this study was to determine whether an antigen cocktail containing recombinantly expressed versions of most of the protective proteases of H‐gal‐GP, a known protective antigen from Haemonchus contortus, would confer any protection to lambs in a vaccine‐challenge trial. Haemonchus contortus metalloendopeptidases, MEP1, MEP3 and MEP4, were expressed as soluble recombinant proteins in insect cells, but attempts to express the H. contortus aspartyl proteases, PEP1 and PEP2, by the… 

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