Content area
Full text
Introduction
Cystic hydatid disease (CHD) is a result of infection with Echinococcus (E.) granulosus at the larval stage. CHD affects sheep, cattle and humans, and occurs throughout the world (1–2). In endemic regions, approximately 50/100,000 individuals have cystic echinococcosis, and prevalence is between 5 and 10% in regions of Argentina, Peru, East Africa, Central Asia and China (3). At present, the major methods for the treatment of CHD include early prevention, drug administration, which typically involves the administration of benzimidazoles such as albendazole and mebendazole, and surgery (4–6). The disadvantage of these methods is the high cost, which is particularly challenging in remote areas and undeveloped countries. Therefore, the development of a treatment method that is relatively cheap and highly efficient at the same time is of critical importance.
Vaccination of livestock may provide an additional approach for the management of CHD. Various studies have reported vaccines for the protection of certain animals, such as sheep, goats and cattle, against hydatid disease caused by the cysts of E. granulosus (7–12).
In a previous study of our group, E. granulosus myophilin (Eg.myophilin) was isolated from a strain of the parasite present in China (13). Furthermore, the immune response and the induced immunoprotection of recombinant Eg.myophilin (rEg.myophilin) were investigated using an experimental model of hydatidosis in mice challenged with E. granulosus protoscoleces (14). It is also known that cytokines and serum antibodies serve an important role in CHD. Cytokine response indicates Th1/Th2 polarization, which is related to the cystic localization, the clinical stage and evolution. Hydatid infection can induce Th1 and Th2 cytokines. Th1 cytokines are associated with protective immunity in echinococcosis, while Th2 cytokines have been suggested to induce susceptibility to the disease. If cytokine response skews Th1/Th2 ratios towards a preferentially immunopathology-associated Th2 polarization, the immune response will benefit parasite growth and development. In addition, serum antibody response is associated with (or is a marker for) cystic development, growth and disease progression (1,15). The present study aimed to investigate the immunoprotection of rEg.myophilin against the establishment of a challenge oral infection using E. granulosus eggs in sheep. In addition, the study investigates the underlying protection mechanisms in order to assess the value of rEg.myophilin as a potential molecular vaccine.
Materials and methods
Ethics statement
The...