抗ＡＴＬＡ抗体測定法４法（ＥＬＩＳＡ法，ＰＡ法，ＩＦ法及びＷＢ法）間における抗体陽性率の比較検討

Abstract

A standard method for antibodies to adult T-cell leukemia-associated antigens (anti-ATLA), indirect immunofluorescence method (IF), is not suitable for mass screening of anti-ATLA. Recently, new methods of testing anti-ATLA suitable for mass screening of anti-ATLA, enzyme-linked immunosorbent assay (ELISA) and gelatin particle agglutination method (PA), have been developed and carried out in many institutes in Japan. However, few comparative study on these methods of anti-ATLA was reported. Therefore, we carried out the comparative study on anti-ATLA among ELISA, PA and IF method, furthermore adding Western blotting method (WB), which has been used for the confirmatory test of anti-ATLA, in the sera from healthy residents in the Kagoshima district, one of the highly endemic areas of human T-cell leukemia virus type I (HTLV-I) in Japan.The results obtained were summarized as follows:1) Of 517 tested sera from healthy residents in the Kagoshima district, positive rate of anti-ATLA was 28.8% (149 sera/517 sera) by PA, 21.1% (109 sera/517 sera) by ELISA and 18.2% (94 sera/517 sera) by IF.2) The coincident rate between IF and PA and that between IF and ELISA was very high (98.6% and 99.5%, respectively) in the positive sera for anti-ATLA, decided by each method.On the other hand, the concordant rate between IF and PA and that between IF and ELISA was not so high (59.7% and 84.4%, respectively) in the negative sera for anti-ATLA.Therefore, PA and ELISA were revealed to be suitable for mass screening in the negative sera for anti-ATLA.3) Of 69 sera, tested by WB, the coincident rate between WB and ELISA was high (90.7%). However, especially in the sera having low titer antibodies (1:16-1:64) by PA, there was disagreement between PA and WB. So it might be careful to decide the positivity of anti-ATLA in the sera having relatively lower titer antibodies by PA.4) Of 69 sera, tested for anti-ATLA by above 4 methods, it was important that there were some sera positive by WB but negative by PA or ELISA. Further studies to clarify the discrepancy between these methods and the developement of a new accurate testing method for anti-ATLA are thought to be necessary.