登革病毒EDⅢ特异性单抗的体内外中和活性观察

摘要

目的 鉴定1株能同时识别登革病毒Ⅰ~Ⅳ型(dengue virus serotypesⅠ-Ⅳ,DENV 1~4)的EDⅢ特异性单抗2D73的体内外中和活性.方法 采用间接酶联免疫吸附实验(ELISA)和间接免疫荧光法(IFA)对单抗2D73的特性进行鉴定,并用基于酶联免疫斑点法的微中和实验(ELISPOT-MNT)和乳鼠保护实验观察单抗2D73对DENV 1~4的体内外中和活性.结果 单抗2D73对4型DENV均具有较强的中和活性,其50%抑制浓度(IC50)分别为0.28、0.16、0.18和18.82 μg/ml.乳鼠保护实验显示,该抗体对DENV 1~4同样具有较好的体内保护效果,与对照组相比,实验组小鼠发病时间明显延迟,生存率显著提高(P<0.05).结论 获得1株同时针对DENV 1~4且具有体内外中和活性的单抗,该单抗可进一步用于DENV致病和免疫机制的研究以及抗病毒药物的研制.%Objective To evaluate the neutralizing activities of a murine monoclonal antibody ( mAb) 2D73 against dengue virus serotypes Ⅰ-Ⅳ( DENV1-4) in vitro and in vivo. Methods Indirect ELISA and immuno fluorescence assay (IFA) were applied to identify specificity of mAb 2D73. Enzyme-linked immunospot micro -neutralizing test (ELISPOT-MNT) was performed to identify its neutralizing activities in vitro, and protective capacity was evaluated in a stringent in -tracranial challenge suckling mice model. Results All the four DENV serotypes were strongly neutralized by mAb 2D73 with 50% inhibitory concentrations (IC50) of 0. 28 , 0. 16 , 0. 18 and 18. 82 μg/ml to DENV1-4 , respectively. The onset of pathogenesis was delayed and the survival rate was improved obviously (P < 0. 05 ) in experimental group compared with control group. Conclusion MAb 2D73 against all the four DENV serotypes has strong neutralizing activities in vitro and protective efficacy in vivo, and might be used for the study of the pathogenic and immunologic mechanism of DENV and for the development of antiviral therapy.