Construction of a protozoan infection therapeutic vaccine development platform technology using antigen-displaying baculovirus

本研究为新孢子虫病组分疫苗的研制奠定了基础。五种候选抗原在家蚕中成功表达并纯化。构建了表达家蚕新孢子虫（Neospora caninum）抗原（NcSAG 1、NcSRS 2和NcMIC 3）的家蚕核型多角体病毒（BmNPV）颗粒。犬的与IgG 1相比，抗原特异性IgG 2a主要通过用NcSAG 1展示的BmNPV颗粒免疫在小鼠中产生，并且IFN-γ的诱导占主导地位，这表明抗原展示的BmNPV颗粒可以在小鼠中引发Th 1免疫应答。半定量PCR分析表明，用从家蚕中纯化的抗原展示BmNPV颗粒免疫小鼠，部分保护小鼠免受脑型N。犬感染这些结果表明，从家蚕中纯化的抗原展示BmNPV颗粒可以提供一种替代方法的新一代N。犬疫苗

In this study, we build the foundation of component vaccine development of neosporosis. Five candidate antigens were successfully expressed and purified in silkworm. Bombyx mori nucleopolyhedrovirus (BmNPV) particles displaying Neospora caninum antigens (NcSAG1, NcSRS2 and NcMIC3) purified from silkworm larvae were constructed to vaccinate mice against N. caninum. Antigen-specific IgG2a was predominantly produced in mice by immunization with NcSAG1-displaying BmNPV particles compared to IgG1, and induction of IFN-gamma was dominant, indicating that antigen-displaying BmNPV particles can elicit a Th1 immune response in mice. Semi-quantitative PCR analysis revealed that immunization with each antigen-displaying BmNPV particle purified from silkworms partially protected mice from cerebral N. caninum infection. These results suggest that antigen-displaying BmNPV particles purified from silkworms can provide an alternative method of a new generation of N. caninum vaccines.