猪链球菌2型人源分离株MRP单克隆抗体的制备与鉴定

Preparation and identification of monoclonal antibodies against muramidase released protein(MRP) of Streptococcus suis serotype 2 isolated from human

为建立一种针对猪链球菌2型（SS2）毒力因子的特异性检测方法，研制了抗SS2溶菌酶释放蛋白（MRP）单克隆抗体（McAb），并对其生物学活性进行了分析。将表达、纯化的SS2菌株MRP免疫BALB／c小鼠，采用淋巴细胞杂交瘤技术将免疫鼠脾细胞与SP2／0骨髓瘤细胞融合，以纯化的MRP蛋白作为包被抗原，通过间接ELISA方法筛选获得了6株能稳定分泌抗MRPMcAb的杂交瘤细胞系288、3G5、1G1、3G9、186和2C3。经用间接ELISA方法测定，单抗腹水的抗体效价均超过1：10^5，杂交瘤细胞培养上清液的效价为1：128～1：1024。Western-blotting鉴定结果表明，6株单抗均具有特异的生物学活性；以288单抗腹水和SS2多克隆抗血清建立的夹心ELISA方法可特异地检测MRP。

Abstract： To establish a specific method for detection of toxicity factors of Streptococcus suis serotype 2（SS2） ,anti-MRP monoclonal antibodies （McAbs） were developed and their biological activities analyzed. The screening result of indirect ELISA with the purified MRP as coating antigen showed that six hybrido- ma cell lines 2B8,3G5,1G1,3G9,1B6 and 2C3 secreting McAb against MRP were obtained by fusion of mouse myeloma cells SP2/0 with splenic cells from BALB/c mice immunized with the purified expression product of MRP. The titers of cultivation supernatants of the 6 hybridoma cell lines ranged from 1 ： 128 to 1 ： 1 024 and the titers of ascites from the mice were over 1 ： 10s. The six McAbs were recognized specifically by MRP in Western-blotting test. A sandwich ELISA for specific detection of MRP was developed using ascites from hybridoma cell line 2B8 and polyclonal anti-serum against SS2.