江苏农业学报2025，Vol.41Issue(3)：549-558,10.DOI:10.3969/j.issn.1000-4440.2025.03.014
鹅星状病毒衣壳蛋白的表达及其免疫的小鼠B细胞受体组库特征分析
Expression of goose astrovirus capsid protein and analysis of B cell recep-tor repertoire characteristics in mice immunized with the capsid protein
摘要
Abstract
This study synthesized and obtained the capsid protein(Cap)gene fragment of goose astrovirus(GoAstV)based on its gene sequence and constructed the recombinant baculovirus rBV-Cap.Through indirect immunofluorescence detec-tion,Western Blot identification,and transmission electron microscopy observation,it was found that rBV-Cap was efficiently ex-pressed in sf9 cells,and the capsid protein(Cap)could self-assemble into virus-like particles similar in structure to the natural GoAstV.The purified capsid protein was used to im-munize BALB/c mice.The results of enzyme-linked immu-nosorbent assay(ELISA)and plaque reduction neutralization tests indicated that the recombinant capsid protein had good immunogenicity and could induce high levels of antibodies in mice.To further explore the characteristics of B cell immune responses,spleen tissues were collected from control mice and immunized mice,and single-cell immune profile sequencing technology was used to sequence the B cell receptor(BCR)repertoire.The re-sults showed that the length of the BCR heavy chain(H)-CDR3 polypeptide chain in control mice was mainly 13 aa,while in im-munized mice,it was mainly 14 aa.Compared with the controls,the number and proportion of immunoglobulin G(IgG)in im-munized mice were increased,indicating that Cap protein could effectively stimulate the production of IgG antibodies in mice.Compared with the controls,the diversity index for BCR repertoire(D50 value)of immunized mice decreased,indicating a re-duction in BCR diversity.However,the cell number of certain clones increased in immunized mice,indicating that immunization could lead to the expansion of specific clones.The usage frequencies of IGHV1,IGHV2 and IGHV5 genes were higher in control mice,while those of IGHV1,IGHV6 and IGHV9 genes were higher in immunized mice.There was no significant difference in the usage frequency of IGHJ genes between control and immunized mice.Compared with the controls,the frequency of IGHV7-3-IGHJ2 and IGHV2-6-2-IGHJ2 pairings increased in immunized mice.The pairings of IGHV2-2-IGHJ1 and IGHV5-1-IGHJ1 were detected in immunized mice but were not detected in control mice,indicating that Cap protein immunization led to changes in V-J gene pairings.This study provides theoretical support for the development of subunit vaccines based on B cell epitopes.关键词
新型鹅星状病毒/衣壳蛋白/B细胞受体/互补决定区Key words
novel goose astrovirus/capsid protein/B cell receptor/complementary determining region分类
农业科技引用本文复制引用
赵冬敏,刘青涛,韩凯凯,黄欣梅,刘宇卓,李银..鹅星状病毒衣壳蛋白的表达及其免疫的小鼠B细胞受体组库特征分析[J].江苏农业学报,2025,41(3):549-558,10.基金项目
江苏省农业科技自主创新基金项目[CX(23)3077] （23）
