0.05). Conclusion pcDNA3.1/SjTs-1 induced the mucosal and systemic immune response and partial protection against the challenge of S.japonicum by the intranasal vaccinations of mice.

Animals ; Disease Models, Animal ; Liver ; parasitology ; Mice ; Mice, Inbred BALB C ; Schistosomiasis japonica ; immunology ; Thiourea ; analogs & derivatives ; pharmacology

OBJECTIVETo obtain peptide mimicking epitopes of Schistosoma japonicum (S. japonicum) through screening of a phage peptide library and to test their potential for induction of protection.

METHODSS. japonicum infected sera from Microtus fortis (IMFS) and normal sera from Microtus fortis (NMFS) were used respectively to screen a 12-mers random peptide library by testing the reactivity of anti-S. japonicum serum with the phagotopes. After three rounds of biopanning, the pooled phages were used to immunize mice, after which challenge infection was performed.

RESULTSOf 12 randomly picked clones, 10 clones selected using IMFS and 7 clones selected using NMFS were shown to be antigenic. Significant reduction in adult worms (22.6%) and a high reduction (68.9%) in liver eggs were achieved following immunization with phages screened with IMFS. However, no protection was elicited by those selected with NMFS.

CONCLUSIONThe results show that the phagotopes are both antigenic and immunogenic, suggesting a potential use of phage displayed peptide as novel vaccines against S. japonicum.

Animals ; Arvicolinae ; parasitology ; Epitopes ; Helminth Proteins ; immunology ; Peptide Library ; Schistosoma japonicum ; immunology ; Schistosomiasis japonica ; prevention & control ; Vaccines ; immunology