IMMUNOREACTIVITY OF RECOMBINANT HUMAN GLANDULAR KALLIKREIN USING MONOCLONAL-ANTIBODIES RAISED AGAINST PROSTATE-SPECIFIC ANTIGEN

The gene encoding human glandular kallikrein (KLK2) was expressed in E scherichia coli, and the corresponding protein (hK2) was produced by f ermentation. The hK2 was characterized by Western blotting and epitope map using monoclonal antibodies (MAbs) specific for another protease, prostate-specific antigen (PSA) with high structural identity (80%). MAbs that recognized three different epitopes were bound to hK2, repre senting 7 out of 23 MAbs tested. One epitope was localized to the sequ ence region around amino acid position 78, which is believed to be gly cosylated in hK2. The affinities of MAbs recognizing hK2 were similar to those for PSA, suggesting that common epitopes seem to contain very conserved structures. The results may help in designing specific diag nostic assays for the assessment of prostate cancer. (C) 1997 Wiley-Li ss, Inc.