Vaccination with recombinant adenovirus expressing multi-stage antigens of Toxoplasma gondii by the mucosal route induces higher systemic cellular and local mucosal immune responses than with other vaccination routes

Wang, Ting; Yin, Huiquan; Li, Yan; Zhao, Lingxiao; Sun, Xiahui; Cong, Hua

Various vaccination strategies against toxoplasmosis in rodent models have been used in the last few decades. However, effective vaccines remain a challenge as tested vaccines have not been able to confer sterile immunity against infection [19] . Current research on T. gondii vaccines only focuses on antigens expressed in the tachyzoite stage, which only induce partial protective immunity [20, 28, 38, 44] . The development of a variety of epitope combinations from different stages of the life cycle, including tachyzoites, bradyzoites (in tissue cysts), and sporozoites (in oocysts), are likely to induce full protection [2, 3, 4, 43] . With the development of bioinformatics, epitope vaccines are considered a novel immunization approach to prevent T. gondii infection. In addition, an appropriate delivery system of vaccines could increase the transfection efficiency of immune cells.