Vacunación frente a la hemoncosis ovina con la proteína recombinante Hc23

Abstract

Infections by the abomasal parasitic nematode Haemonchus contortus are responsible of important losses of productivity in ruminants particularly sheep. The control of this disease has been largely based on the use of anthelmintics. However, the indiscriminate administration of drugs, lack of strategic planning, drug rotation and unknowledge of the epidemiology of the process have provoked the widespread appearance of anthelmintics resistance. Furthermore, concerns have been raised regarding the presence of pharmacologically active residues both in food for human consumption and in the environment. Therefore, it is necessary to explore new alternative or complementary control methods among them immunoprophylaxis. Under controlled conditions, some proteins have shown to induce protection against H. contortus infections. A number of potentially protective hidden antigens (HAGs) of H. contortus have been cloned and expressed but limited attempts have been made to clone natural antigens (NAGs). As a rule, while some native proteins have been able to elicit a significant protective response against haemonchosis their recombinant counterparts fell behind the expectations. However, the economic importance of this parasitic disease, anthelmintic resistance developed in many regions of the world together with the impracticality of immunization with native proteins make necessary the use of recombinant proteins. The aims of our project were the purification of both native (Hc23) and recombinant (rHc23) forms of the protein Hc23 from adult worms since this protein has previously shown to induce a partially protective immune response. In addition the potential immunoprophylactic value against haemonchosis of native and recombinant Hc23, administered with different adyuvants, was tested in experimentally infected lambs