免疫增强剂CVC1302辅助抗原诱导小鼠机体产生长效体液免疫应答的研究  

The mechanism of immunopotentiator CVC1302 in promoting long-term humoral immune responses in mice

作　　者：杜露平[1,2] 侯立婷 于晓明[1,2] 程海卫 郑其升[1,2] 陈瑾 DU Luping;HOU Liting;YU Xiaoming;CHENG Haiwei;ZHENG Qisheng;CHEN Jin(Institute of Veterinary Immunology & Engineering/National Research Center of Engineering and Technology for VeterinaryBiologicals/Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base,Ministry ofScience and Technology,Nanjing 210014,China;Jiangsu Co-innovation Center for Prevention andControl of Important Animal Infectious Diseases and Zoonoses,Yangzhou 225009,China)

机构地区：[1]江苏省农业科学院动物免疫工程研究所/江苏省国家兽用生物制品工程技术研究中心/江苏省食品质量安全重点实验室,江苏南京210014 [2]江苏省动物重要疫病与人兽共患病防控协同创新中心,江苏扬州225009

出　　处：《南京农业大学学报》2022年第3期597-603,共7页Journal of Nanjing Agricultural University

基　　金：国家自然科学基金项目(31802220);江苏省农业自主创新专项[CX(20)3096]。

摘　　要：[目的]本试验旨在探究免疫增强剂CVC1302促进淋巴滤泡生发中心(GC)应答的作用机制。[方法]将模式抗原4-羟基-3-硝基苯乙酰基耦联鸡卵白蛋白(NP-OVA)与CVC1302配伍后,与ISA206佐剂乳化制备疫苗NP-CVC1302,免疫6周龄BALB/c雌性小鼠。免疫后不同时间点,利用NP-BSA作为捕获抗原检测小鼠血清NP^(+)抗体水平及亚型抗体水平。免疫后14 d,流式细胞术检测腹股沟淋巴结的滤泡辅助性T细胞(T_(FH)细胞)、NP^(+)GC B细胞、NP^(+)浆母细胞比例;激光共聚焦显微镜检测GC数目;免疫后42 d,流式细胞术检测骨髓处NP^(+)长寿浆细胞(LLPC)比例。[结果]NP-CVC1302组小鼠NP特异性抗体水平极显著高于NP组(P<0.01),且NP特异性IgG_(1)、IgG_(2a)抗体水平也显著高于NP组(P<0.05或P<0.01);NP-CVC1302组小鼠腹股沟淋巴结T_(FH)细胞和NP^(+)GC B细胞比例极显著高于NP组(P<0.01或P<0.001),且GC数目也极显著高于NP组(P<0.01);此外,骨髓处NP^(+)LLPC比例也极显著高于NP组(P<0.01)。[结论]CVC1302通过促进腹股沟淋巴结处T_(FH)细胞分化,通过对NP^(+)GC B细胞进行正向选择,促使其分化为浆母细胞,进而随着血流进入骨髓形成LLPC,持续分泌NP^(+)抗体,为机体提供体液保护力。[Objectives]This study aimed at deciphering the mechanisms of CVC1302 in promoting germinal center(GC)responses.[Methods]Pattern antigen 4-hydroxy-3-nitrophenylacetyl(NP)-ovalbumin(OVA)were mixed with CVC1302 followed by emulsified with ISA206,named as NP-CVC1302.Six-week-old BALB/c femal mice were immunized with NP-CVC1302,NP or ISA206,and the sera were collected to detect the NP-specific antibody titers and isotype antibody titers.The percentages of follicular helper T cells(T_(FH)),NP^(+) GC B cells and NP^(+) plasma-blasts in inguinal lymph nodes and the numbers of GC were measured at 14 days post immunization(dpi).Furthermore,the percentage of NP^(+) long-lived plasma cells(LLPC)in bone marrow was also detected at 42 dpi by using flow cytometry.[Results]Through the detection,we found that NP-specific antibody titers were significantly higher in NP-CVC1302 group compared with NP group(P<0.01),as well as the NP-specific IgG_(1) and IgG_(2a) antibody titers.Significantly higher percentages of T_(FH) cells,NP^(+) GC B cells and NP^(+) plasma-blasts in inguinal lymph nodes were induced in NP-CVC1302 group compared with NP group(P<0.01 or P<0.001).Moreover,significantly higher percentage of LLPC was transferred into the bone marrow of mice that received NP-CVC1302 compared with those that received NP(P<0.01).[Conclusions]Results of the study revealed that CVC1302 improved the differentiation of T_(FH) cells,then T_(FH) cells selected the high-affinity GC B cells to differentiate into plasma-blasts,and finally became LLPC locating in the bone marrow,continuing to secrete antibody.This study provided the blueprint for designing new generations of immunopotentiators.

关 键 词：小鼠 免疫增强剂 模式抗原 4-羟基-3-硝基苯乙酰基耦联鸡卵白蛋白(NP-OVA) 生发中心应答 滤泡辅助性T细胞 

分 类 号：S855.3[农业科学—临床兽医学]