捕捉法ELISA检测脊髓灰质炎IgA抗体方法的建立与应用

ESTABLISHED A CAPTURE ELISA FOR DETECTING POLIO IgA ANTIBODY USING FOR RAPID DIAGNOSIS OF POLIOVIRUS INFECTION

建立了一种检测脊髓灰质炎(简称脊灰)IgA抗体的捕捉法ELISA(Aac-ELISA)。方法敏感,快速,特异,用于检测144份脊灰可疑病人的血清,IgA抗体检出率为77.8％(112/144).而这些血清的IgM抗体检出率为65.2％(94/144)。如同时检测IgM和IgA抗体,则阳性率可达91.7％(132/144)。麻痹后1～3天内IgA的检出率为76.5％(13/17),4～7天内为95％(19/20)。最长检出IgA的一例可疑病人,其血清收集于病后第59天。本方法在一部分16天后可疑病人IgM阴性血清中查出IgA阳性,故可以作为查IgM抗体诊断方法的补充,尤其适用于诊断感染后未能及时收到血清标本,IgM已经转阴而IgA抗体仍为阳性的病人。

A capture-ELISA for detecting specific IgA antibody (Aac-ELISA) as a sensitive and rapid diagnosis of type 1 poliovirus infection was deve loped. The test can be blooked by type 1 poliovirus antigen only and has no cross reaction with some other enterovirus antigens such as type 2 poliovirus, type 3 poliovirus, Cox A24, Cox B6 and EV71. The positive detecting rate of IgA in 144 polio suspected case sera were as follows, 65.2% by IgM antibody Captur-ELISA test(Mac-ELISA), 77.8% by Aac-ELISA test and 91.7% by both of the test. The data shows that to detect IgA antibody could be a supplement test for detecting polio IgM antibody to increase the positive detecting rate of poliovirus infection.By the day after onset of the illness, the positive detecting rate of the IgA antibody was as follows, lst-3rd were 76.5%(l3/l7),4-7th were 95% ( 19/20) . In the sera collected at the 31st-60th days after onset of the disease, no one could be found out IgM antibody, but 7 of the 10 suspected case sera were positive of IgA antibody. At that time the IgM antibody response may be decreased under the detecting Ievel, but the IgA antibody were stili positive. So the IgA Capture-ELISA was a use ful test for polio diagnosis, especcially for the patients from which the sera were collected late for example in 1-2 months after onset of disease.