ANA detected by ELISA using nucleus of egg cell as antigen.

Antinuclear antibodies, ANA, were usually detected with antigen of somatic cell nucleus. It has not been reported to detect ANA with egg cell nucleus as antigen. Enzyme linked immuosorbent assay, ELISA, coated with yolk was developed to detect ANA in our laboratory. A quality control test, cross absorption test, and cross antibody-induced test with yolk were performed. Results showed a good agreement between our method and IFA through measurement of the same samples from patients suspected of having rheumatic connective tissue diseases (Kappa=0.668, P=0.000). The results were not influenced by the RF and different sources of egg. CVs of inter-assay, were less than 10%. The cross absorption test was negative, as well; the ANA to somatic cell nucleus could be induced with egg cell nucleus. It is implied that there were both cross as well as overlapped Egg-ANA and Somatic-ANA. As egg nucleus, its volume was large, its purification was simple, so the better method might be established.