柔嫩艾美耳球虫表面抗原SAG12对鸡的免疫保护效果评价  

Evaluation of the Immunoprotective Effect of Surface Antigen SAG12 of Eimeria tenella on Chickens

作　　者：王磊 游怡宁 吴天乐 孙雪 王冰楠 毕师诚 周荣琼 WANG Lei;YOU Yining;WU Tianle;SUN Xue;WANG Bingnan;BI Shicheng;ZHOU Rongqiong(School of Veterinary Medicine,Southwest University,Rongchang Chongqing 402460,China)

机构地区：[1]西南大学动物医学院,重庆荣昌402460

出　　处：《西南大学学报（自然科学版）》2025年第2期17-25,共9页Journal of Southwest University(Natural Science Edition)

基　　金：国家自然科学基金项目(32473075)。

摘　　要：为评估柔嫩艾美耳球虫(Eimeria tenella,E.tenella)表面抗原(Surface antigen,SAG)SAG12对鸡的免疫保护效果,首先构建EtSAT12/pET-32a原核表达载体,对EtSAG12重组蛋白进行纯化并制备多克隆抗体;然后进行动物试验,将100只1日龄海兰灰雏公鸡分成5个组,分别是感染对照组(PC)、空白对照组(NC)、EtSAG12重组蛋白50μg、100μg和150μg组。通过统计相对增质量率、卵囊减少率、抗球虫指数(ACI)和血清中特异性IgG抗体等指标评价EtSAG12重组蛋白的免疫保护效果。结果显示:成功表达出EtSAG12重组蛋白,大小约为43 Ku,主要以可溶性形式表达;Western Blot结果显示所制备的多克隆抗体有较强的特异性。免疫保护试验结果显示:与PC组相比,3个重组蛋白组的平均增质量显著增加(p<0.05)、病变计分显著降低(p<0.05),且均能有效降低卵囊产量,其中重组蛋白150μg组相对增质量率(97.34%)和卵囊减少率(52.54%)均为最高,ACI值达到165.34,具有中效抗球虫效果;3个重组蛋白组血清中特异性IgG抗体水平与PC组和NC组相比,在p<0.05水平差异均有统计学意义,且二免7 d后血清中特异性IgG抗体水平达到最高,其中重组蛋白150μg组特异性IgG抗体水平最高,且显著高于另外两个重组蛋白组(p<0.05)。综上所述,EtSAG12重组蛋白能减轻因球虫感染导致的增质量损失和肠道病变,减少卵囊排出,刺激宿主产生体液免疫,具有一定的免疫保护作用。To evaluate the immunoprotective effect of the surface antigen(SAG)SAG12 of Eimeria tenella(E.tenella)on chickens.The prokaryotic expression vector EtSAT12/pET-32a was constructed.The EtSAG12 recombinant protein was purified and polyclonal antibody was prepared.In the animal experiment,100 one-day-old Hy-Line Sonia male chicks were divided into five groups:infection control group(PC),blank control group(NC),and EtSAG12 recombinant protein 50μg,100μg,and 150μg groups.The immunoprotective effect was assessed by measuring relative weight gain,oocyst reduction rate,lesion score,anti-coccidial index(ACI)and the levels of IgG in serum.The results showed that the EtSAGR12 recombinant protein was about 43 Ku in size and mainly expressed in soluble form.Western Blot showed that the antibody had good specificity.Compared to the PC group,the three immunized groups showed significantly higher weight gain(p<0.05),lower lesion scores(p<0.05),and reduced oocyst output.In the group immunized with 150μg,the relative weight gain(97.34%)and the oocyst reduction rate(52.54%)were the highest,with an ACI of 165.34,indicating moderate anticoccidial effects.The levels of IgG in serum antibody levels were significantly higher in the immunized groups than in the PC and NC groups(p<0.05),and reached peak at 7 days after the second immunization,with the 150μg group showing the highest levels(p<0.05).In summary,The EtSAG12 recombinant protein can reduce weight loss and oocyst shedding,stimulate humoral immunity in the host,and have a certain degree of immunoprotective effect against coccidial infection.

关 键 词：柔嫩艾美耳球虫 EtSAG12重组蛋白 原核表达 免疫保护效果 表面抗原 

分 类 号：S852.4[农业科学—基础兽医学]