IMMUNIZATION WITH LIVE ATTENUATED SALMONELLA-DUBLIN EXPRESSING A SPOROZOITE PROTEIN CONFERS PARTIAL PROTECTION AGAINST THEILERIA-PARVA

Cattle immunised with a recombinant form of p67, the major surface ant igen of Theileria parva sporozoites, have been shown to be protected a gainst parasite challenge. In an attempt to simplify the immunisation procedure live attenuated Salmonella strains expressing p67 have been constructed and used to induce anti-p67 immune responses in cattle. Al l animals immunised with these strains developed strong antibody respo nses to p67. Specific T cell responses could be detected in the majori ty of immunised cattle. Challenge with T. parva sporozoites revealed a significant level of protection in immunised calves compared to naive control animals or animals inoculated with non-recombinant attenuated Salmonella. (C) 1998 Elsevier Science Ltd. All rights reserved.