摘要
共研制出11株抗大肠杆菌987P 粘着素单克隆抗体,对其部分免疫学特性作了测定。这些单抗不仅效价很高,而且特异性强,对不具有987P 抗原的大肠杆菌及所试的其他肠道杆菌均无交叉反应。以 FITC 或 HRPO 标记的987P 单抗作实验室诊断,具有简易、快速、敏感和准确的优点。酶标 EPN3株单抗检测的灵敏度可达2×10~3个/ml 987P^+菌,对人工发病仔猪的粪样和小肠内容物的阳性检出比分别为4/4和2/2。EP22株荧光标记单抗对病猪小肠粘膜触片的阳性检出比为6/6。11株单抗中7株能不同程度地阻断987P^+菌对仔猪小肠上皮细胞的吸附作用。ELISA 和荧光阻抑试验表明,11株单抗是针对987P 粘着素上三种不同的抗原决定簇。EPN2株单抗的免疫胶体金定位还表明,987P 粘着素似呈螺旋状结构,且含有许多相同的抗体结合位点。这些单抗不仅可用于 ETEC 菌株的987P 柔毛鉴定,而且可用于987P 分子结构和生物学特性的研究。
A panel of 11 monoclonal antibodies(MAbs) to 987P adhesin antigen of E.coliwere developed and partially characterized.They only reacted with E.coli strains bea-ring 987P adhesin but neither with other E.coli (K88^+,K99^+ and F41~~) strains norother species in family of Enterobacteriaceaein IF or ELISA.The amount of 987P^+ bac-teria which could be detected by the HRPO-conjugated MAb EPN3 was as small as 2×10~3 cells/ml,and the detected rate of fecal orintestinal samples from piglets with artifici-ally induced diarrhoea by IF and /or ELISAwas 4/4 and 6/6,respectively.The adhesionof 987P^+ E.coli to porcine intestinal epithe-lial cells could be inhibited by seven of theseMAbs in vitro.The binding pattern of MAbEPN2 with 987P fimbriae as shown in im-munogold stain under electron microscopewas periodic and discrete distribution alongthe length of each of the fimbriae.ELISAand IF blocking test suggested that there wereat least 3 kinds of determinants on 987P ad-hesin.These MAbs were not only useful inidentification of 987P fimbriae of enterotoxi-genic E.coli,but also in the studies of its mo-lecular structure and biological function.
出处
《微生物学报》
CAS
CSCD
北大核心
1990年第1期41-47,共7页
Acta Microbiologica Sinica
关键词
大肠杆菌
粘着素
单克隆抗体
Escherichia coli
987P adhesin
Monoclonal antibody
