Epitope Mapping of HIV1 gp41 Protein for Korean Anti - HIV1 Antisera using Synthetic Peptides

Hahm, Kyung Soo; Lee, Myung Kyu; Shin, Song Yub; Kim, Sun Young; Jang, So Youn

Abstract

The N-terminal sequence of HIV1 gp41 (amino acid residues 584-623) was known to be the immundominant region of HIV1 gp41 protein. In order to determine epitope for gp41 protein of Korean anti-HIV1 positive sera, multiple antigenic peptides (MAPs) for the sequences corresponding to 584-604, 590-612, 604-623 and 584-618 of HIV1 gp41 were synthesized by solid phase method using Fmoc-Lys (Fmoc)-OH and used as coating antigens for ELISA. The reactivities of the synthetic peptides with Korean HIV1 positive (21 samples) and anti-HIV1 negative sera (22 samples) obtained from healthy blood doner were estimated by an indirect ELISA. MAPs for 584-604, 590-612 and 604-623 of gp41 reacted with 62 %, 100 % and 81 % of Korean anti-HIV1 positive sera tested, respectively. The results suggest that the epitope for HIV1 gp 41 for Korean anti-HIV1 positive sera is located in the region of amino acid 590-612 of gp41. MAP for gp41 (584-618) reacted with all (100 %) of anti-HIV1 positive sera tested, but did not react with anti-HlV1 negative sera. In addition, this MAP reacted stronger with seven samples of anti-HIV1 positive sera of anti-HIV1/2 combo performance panel than the mixture of 584-604, 590-612 and 604-623 of gp41, but did not react with anti-HIV negative serum. The high sensitivity and selectivity of MAP of gp41 (584-618) suggest that this peptide as a coating antigen in an ELISA system will be useful for antibody detection of HIV1.