PT  - JOURNAL ARTICLE
AU  - K. TODOROVA
AU  - S. ZOUBAK
AU  - M. MINCHEFF
AU  - S. KYURKCHIEV
TI  - Biochemical Nature and Mapping of PSMA Epitopes Recognized by Human Antibodies Induced after Immunization with Gene-based Vaccines
DP  - 2005 Nov 01
TA  - Anticancer Research
PG  - 4727--4732
VI  - 25
IP  - 6C
4099  - http://ar.iiarjournals.org/content/25/6C/4727.short
4100  - http://ar.iiarjournals.org/content/25/6C/4727.full
SO  - Anticancer Res2005 Nov 01; 25
AB  - Background: A possible new target for immunotherapy is the prostate-specific membrane antigen (PSMA). The aim of the present study was to define potential PSMA epitopes for antibody binding using sera from patients immunized with gene-based anti-PSMA vaccines. Materials and Methods: Sera from prostate cancer patients, immunized repeatedly with plasmid and adenoviral vectors, each encoding for the extracellular portion of human PSMA, were tested for anti-PSMA antibodies by Western blot. PSMA-producing LNCaP cells were used as a control. Recombinant PSMA protein cleaved with different proteinases was used for epitope mapping. Different enzymes were used to cleave the PSMA molecule. Results: Specific anti-PSMA antibodies were detected in the studied patients' sera, mainly against the PSMA protein core. An alignment of the predicted enzyme-cleavage fragments was compared with Western blot results and several antibody epitopes were determined. Conclusion: These data demonstrate that multiple gene-based vaccinations induce an anti-PSMA humoral immune response. The antibodies are predominantly specific for the PSMA protein core. Copyright© 2005 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved