A SMALL HEAT SHOCK PROTEIN OF OSTERTAGIA OSTERTAGI: STAGE-SPECIFIC EXPRESSION, HEAT INDUCIBILITY, AND PROTECTION TRIAL

In this study, we isolated and analyzed a small heat shock protein (HSP) of Ostertagia ostertagi (Oo-HSP18). Oo-hsp18 is encoded by a single-copy gene and the full-length cDNA represents an 18-kDa protein. The expression of Oo-hsp18 is highly stage specific and restricted to the adult stage. The protein is synthesized in a tissue-specific manner and localized in the body muscle layer. The levels of Oo-hsp18 mRNAs are sharply induced by heat shock but not by other stressors such as levamisole and H₂O₂. A vaccination trial with recombinant Oo-HSP18 failed to protect calves against a challenge infection.