Sequential immunization with domain Ⅲ of dengue envelope proteins induces immune responses against dengue virus
10.3760/cma.j.issn.0254-5101.2018.03.002
- VernacularTitle:序贯免疫策略诱导抗登革病毒免疫应答的研究
- Author:
Xin WANG
1
,
2
;
Min LI
;
Xia JIN
Author Information
1. 200444 上海大学,生命科学学院
2. 200031 中国科学院上海巴斯德研究所,分子病毒与免疫重点实验室
- Keywords:
Tetravalent dengue vaccine;
Sequential immunization;
Antibody response;
T cell re-sponse
- From:
Chinese Journal of Microbiology and Immunology
2018;38(3):169-175
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate whether a novel sequential immunization strategy was more superior to the traditional immunization strategy in eliciting immune responses by using domainⅢof dengue envelope proteins (EDⅢs) as immunogens. Methods EDⅢ subunit proteins of four serotypes of dengue viruses (DENVs) were expressed in a baculovirus expression system. SDS-PAGE and Western blot were performed to analyze the purity and specificity of purified recombinant proteins, respectively. In order to evaluate the immunogenicity of EDⅢ-based immunization strategies, female BALB/c mice were subcutane-ously immunized with PBS,tetravalent mixture of four EDⅢrecombinant proteins,or the four EDⅢproteins sequentially for four times with two weeks interval between each immunization. Two-week after the final im-munization,splenocytes were isolated and analyzed by ELISPOT assay to evaluate T cell responses and serum samples were collected for plaque reduction neutralization test(PRNT). Results Both immunization strate-gies of sequential EDⅢproteins and tetravalent EDⅢproteins could elicit stronger antigen-specific Th2(IL-4) cell responses in immunized mice than PBS did and the former was superior to the latter. Only the se-quential immunization strategy could induce Th2 cell responses in immunized mice against peptide segments of DENV2 EDⅢ. Tetravalent EDⅢ proteins performed better than the sequential immunization strategy in inducing higher levels of neutralizing antibodies against DENV-1,DENV-2 and DENV-3,while both immu-nization strategies failed to generate neutralizing antibodies against DENV-4. Conclusion Sequential immu-nization with DENV EDⅢ proteins induced stronger T cell responses, but weaker neutralizing antibody re-sponses against DENV than tetravalent EDⅢ proteins did.
