Autoantibodies in sera of pancreatic cancer patients identify recombination factor Rad51 as a tumour-associated antigen.
OBJECTIVE
The recombination factor Rad51 is highly expressed in human pancreatic adenocarcinoma. In this study we asked whether high-level expression of Rad51 antigen stimulates a B-cell response leading to Rad51-specific autoantibodies in human pancreatic cancer patients.


METHODS
Sera of patients suffering from pancreatic cancer (57) as well as sera of healthy donors (86) were screened for Rad51 autoantibodies by Western-blot analysis. Rad51 over-expressing cell lines were used as antigen source.


RESULTS
Four out of 57 (7%) sera tested were found positive for Rad51 autoantibodies of IgG subclass, while all 86 control sera were negative.


CONCLUSIONS
This observation identifies Rad51 as a tumour-associated antigen in pancreatic adenocarcinoma. Since high-level expression of Rad51 is restricted to tumour cells, Rad51 is also a tumour-specific antigen. Further analyses should reveal whether Rad51 might also function as a tumour-specific transplantation antigen (TSTA) and whether it might serve as a target for new immunotherapeutical approaches.
Maacke
H
H
Present address: Clinic for Internal Medicine II, Friedrich-Schiller University Jena, Erlanger Allee 101, 07743 Jena, Germany.
Hundertmark
C
C
Miska
S
S
Voss
M
M
Kalthoff
H
H
Stürzbecher
H-W
HW
D000230:Adenocarcinoma / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D000951:Antigens, Neoplasm / Q000032:analysis / Q000096:biosynthesis* / Q000276:immunology; D001323:Autoantibodies; D014408:Biomarkers, Tumor / Q000032:analysis / Q000276:immunology*; D015153:Blotting, Western; D004268:DNA-Binding Proteins / Q000032:analysis / Q000096:biosynthesis* / Q000276:immunology; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007150:Immunohistochemistry; D010190:Pancreatic Neoplasms / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D051135:Rad51 Recombinase
D000951:Antigens, Neoplasm; D001323:Autoantibodies; D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D007074:Immunoglobulin G; C495153:RAD51 protein, human; D051135:Rad51 Recombinase