PL-005 Profile of HBsAg levels in patients with dual hepatitis B virus and hepatitis C virus infection treated with peginterferon alfa-2a and ribavirin

Abstract

for preventing Trichinella spiralis infection. We have previously reported that a recombinant Ts87 protein was considered as a potential candidate vaccine for Trichinella spiralis. In this study mucosal immune responses induced by SL7207/pvax1-Ts87 were assessed. Methods: We constructed a recombinant plasmid pvax1-Ts87, and evaluated safety, stability of SL7207/pvax1-Ts87, a DNA vaccine delivered in attenuated Salmonella typhimurium, and immune responses induced by immunizing BALB/c mice orally with SL7207/pvax1-Ts87 of 108 CFU dosage. After the final boost, mice were challenged orally with 500 Trichinella spiralis infective muscle larvae for per mouse. Results: Oral immunization of mice with SL7207/pvax1-Ts87 elicited significant elevation of intestinal secretory IgA and serum anti-Ts87 IgG. The immunized mice exhibited a high ratio of IgG1 to IgG2a. Splenocytes were isolated after the immunization to determine the antigen-specific T-cell response by the ELISPOT assay. The result showed that CD4+ T cells produced IFN-γ, IL-4, IL-5, IL-6 and IL-10. Immunofluorescent microscopy revealed that the recombinant Ts87 protein was expressed in the dendritic cells of mesenteric lymph nodes. Furthermore BALB/c mice vaccinated with SL7207/pvax1-Ts87 demonstrated 29.8% reduction in adult worm burden and muscle larval reduction (34.2%) following Trichinella spiralis larvae challenge. Conclusion: Our results demonstrated a SL7207/pvax1-Ts87 DNA vaccine delivered in attenuated Salmonella typhimurium can elicit specific immune response as well as provide effective protection against Trichinella spiralis infection in mice.