Optimized codon usage enhances the expression and immunogenicity of DNA vaccine encoding Taenia solium oncosphere TSOL18 gene

Abstract

Cysticercosis due to larval cysts of Taenia solium, is a serious public health problem affecting humans in numerous regions worldwide. The oncospheral stage-specific TSOL18 antigen is a promising candidate for an anti-cysticercosis vaccine. It has been reported that the immunogenicity of the DNA vaccine may be enhanced through codon optimization of candidate genes. The aim of the present study was to further increase the efficacy of the cysticercosis DNA vaccine; therefore, a codon optimized recombinant expression plasmid pVAX1/TSOL18 was developed in order to enhance expression and immunogenicity of TSOL18. The gene encoding TSOL18 of Taenia solium was optimized, and the resulting opt-TSOL18 gene was amplified and expressed. The results of the present study showed that the codon-optimized TSOL18 gene was successfully expressed in CHO-K1 cells, and immunized mice vaccinated with opt-TSOL18 recombinant expression plasmids demonstrated opt‑TSOL18 expression in muscle fibers, as determined by immunohistochemistry. In addition, the codon-optimized TSOL18 gene produced a significantly greater effect compared with that of TSOL18 and active spleen cells were markedly stimulated in vaccinated mice. 3H-thymidine incorporation was significantly greater in the opt-TSOL18 group compared with that of the TSOL18, pVAX and blank control groups (P<0.01). In conclusion, the eukaryotic expression vector containing the codon-optimized TSOL18 gene was successfully constructed and was confirmed to be expressed in vivo and in vitro. The expression and immunogenicity of the codon-optimized TSOL18 gene were markedly greater compared with that of the un-optimized gene. Therefore, these results may provide the basis for an optimized TSOL18 gene vaccine against cysticercosis.

Perturbations of Metabolomic Profiling of Spleen From Rats Infected With Clonorchis sinensis Determined by LC-MS/MS Method

“…Additionally, deoxyadenosine could dampen the function of immune cells by triggering the caspase-3-mediated death of macrophages ( Carrera et al, 1990 ; Thammavongsa et al, 2013 ), which was down-regulated in this present study. As a precursor of DNA, thymidine was down-regulated, which indicating the degree of lymphocytes proliferation ( Wang et al, 2015 ). Taken together, the metabolites suppressed immunity was significantly decreased, indicating that the host actively regulates the immune response, despite the spleen cells were damaged and the proliferation was inactive.…”

Introductory Chapter: Taeniasis and Cysticercosis/Neurocysticercosis – Differences, Risk Factors, and Vaccines

“…In mice, the expression and immunogenicity of the codon-optimized TSOL18 gene were much higher than those of the unoptimized gene. These findings provide the groundwork for developing an improved TSOL18 gene vaccination against cysticercosis [31]. The TSOL16 antigen (for ovine psoroptic mange control) might be a beneficial addition to existing swine vaccination approaches, allowing for the development of novel T. s o l i u m cysticercosis vaccine tactics [32].…”