猪链球菌血清2型抗体IHA检测方法的建立及应用

Development and application of an indirect hemagglutination assay for detection of antibodies against Streptococcus suis serotype 2

用猪链球菌血清2型(Streptococcus suis serotype 2,SS2)的荚膜多糖(Capsular polysaccharide,CPS)致敏经戊二醛处理过的鸡红细胞,优化致敏醛化红细胞的抗原量和时间。结果显示,在37℃条件下CPS(2.2 5mg/L)致敏鸡红细胞90min,IHA试验在25℃条件下操作,被检血清IHA效价在1∶8及其以上时判为SS2抗体阳性。应用此方法对猪大肠杆菌、副嗜血杆菌、猪肠球菌、SS1、SS7、SS9、金黄色葡萄球菌、沙门菌、巴氏杆菌阳性血清进行检测,结果表明,SS2抗体均为阴性。对1044份无临床症状的猪血清进行检测,SS2抗体阳性率为61.69%。该方法敏感性高,特异性较强,可用于大规模SS2抗体水平的检测和SS2的血清流行病学调查。

To establish an indirect hemagglutination assay（IHA） for detection of antibodies against SS2,the glutaraldehyde-fixed chicken red blood cells（CRBC） were sensitized by capsular polysaccharide of SS2.The best antigen concentration was 2.25 mg/L.The serum is positive if antibody titre was≥1∶16.The positive sera against Escherichia coli,haemophilus parasuis,Enterococcus,SS1,SS7,SS9,staphylococcus aureus,Salmonella typhimurium,Pasteurella multocida showed negative reaction to the CPS antigen of SS2 used in IHA.Examination of 1044 serum samples revealed that the positive ratio of antibody against SS2 was 61.69%.These data indicated that the IHA established is sensitive,specific for detecting antibody against SS2.