血清中Epstein-Barr病毒膜抗原IgA抗体检测法的改进及应用

用萄葡球菌菌体A蛋白(SPA)预先处理被检血清,以去除抗体IgG部份的竞争性结合,提高了间接免疫荧光法检查鼻咽癌病人血清中EB病毒膜抗原IgA(IgA/MA)抗体的敏感性及特异性,检查48例鼻咽癌病人血清IgA/MA抗体,阳性率为100％,血清几何平均滴度为141;40例其它恶性肿瘤病人和46例正常人都检不出IgA/MA抗体,免疫荧光法测得IgA/MA抗体阴性的6例鼻咽癌病人血清,SPA吸收后呈阳性反应,此改进方法可用以追踪观察鼻咽癌病的病程及预后。

DEVELOPMENT AND APPLICATON OF A NEW TECHNIQUE FOR THE DETECTION OF IgA ANTIBODY TO EPSTEIN-BARR VIRUS MEMBRANE ANTIGEN

IgA antibody to membrane antigen ( MA ) of Epstein-Barr Virus ( EB V) was examined in sera from 48 nasopharyngeal carcinoma(NPC ) patients, 40 patients with tumors other than NPC and 46 normal individuals after pre-absorption of sera with staphylococcus aureus ( SPA) strain No. 1800 and by indirect immunofluorescence test. One hundred percent of the NPC patients had the IgA/MA antibody with a GMT of 1 : 141. In patients with tumors other than NPC or normal individuals, IgA/MA antibody was not detectable. IgA/MA antibody has been demonstrated in six NPC patients lacking detectable antibody levels by the indirect immunoflourescence test using non-absorbed sera. Our data indicate that preabsorption of sera with SPA renders the diagnostic test significantly more sensitive for the detection of the nasopharyngeal carcinoma and can be used for screening for patients.