Haematologia 23. (1990)
1990 / 1. szám - Ujhelyi, E. - Illei, G. - Bohm, U. - Füst, G. - Dierich, M. M. - Szelényi, J. - Merétey, K. - Hofbauer, J. - Hollán, S. R.: E. coli antibodies do not cause false-positivity in recombinant anti-HTV assay
1* Haematologia 23 (I), pp. 3— 7 (1990) E. Coli Antibodies Do Not Cause False-positivity in Recombinant Anti-HIV Assays E. Újhelyi,1 G. Illei,1 U. Böhm,2 G. Füst,1*, M. M. Dierich,3 J. Szelényi,1 K. Merétey,2 J. Hofbauer,3 S. R. Hollán1 1NationaI Institute of Haematology and Blood Transfusion, Budapest, POB 44, H-1502, Hungary, 2National Institute of Rheumatology and Physiotherapy, Budapest, institute for Hygiene, University Medical School, Innsbruck, Austria (Received 16 November, 1988; accepted 19 December, 1988) 129 sera with known antibody titres against E. coli 026 and E. coli 055 strains were tested with the Abbot second generation anti-HTLV III recombinant screening assay. No difference in the O.D. values was found between sera with high, normal and low anti-E. coli titres. In addition, no false-positive reactions were observed with the anti-HIV negative sera containing E. coli antibodies in high titres in a Western blot assay in which recombinant env antigen was applied. These results suggest that E. coli assays in which E. coli-produced recombinant antigens are used. Keywords: E. coli antibodies, recombinant anti-HIV assay, false positivity Introduction As a result of the development of HIV serology, improved, second generations ELISA tests are more and more frequently used for screening blood donors and members of high risk groups for HIV antibodies. In most second generation assays, plates or beads are coated with recombinant env and/or core antigens. In addition, recombinant HIV antigens are applied in some experimental Western blot assays as well [2, 5]. Use of these antigens excludes the possibility of false-positive reactions due to anti-HLA and other anti-lymphocyte antibodies [3,4,6]. Since, however, recombinant antigens are produced mostly in different strains of E. coli, theoretically it is possible that some antigens of bacterial origin can be present even in the purified HIV env and core antigen preparations. If recombinant HIV antigens are really contaminated with bacterial antigens, false-positive anti-HIV reactions can develop when serum samples containing anti-E. coli antibodies in high titres are tested. * To whom correspondence should be addressed VSP Utrecht, Tokyo Akadémiai Kiadó, Budapest