Naturally occurring antibodies to epithelial cell adhesion molecule (EpCAM).
Epithelial cell adhesion molecule (Ep-CAM) is an epithelial tumor-associated antigen that is expressed by a number of normal tissues and has been used as a target in many immunotherapy studies. The purpose of this study was to determine the incidence of serum anti-EpCAM IgG (immunoglobulin G) antibodies in colon cancer and tumor-free patients and to assess the tumor protective value of anti-EpCAM antibodies. One third of both the cancer (16/48) and the control (9/27) patients had detectable antibodies. Although the mean antibody concentration was higher in cancer patients (0.048 +/- 0.120 U) than in controls (0.038 +/- 0.064 U) the difference was not statistically significant. Western blot analysis revealed reactivity to multiple HT29 cell proteins including a 40-kDa protein (presumed to be Ep-CAM). Monoclonal anti-EpCAM 323/A3 antibody did not have a tumor-protective effect in murine Ep-CAM expressing colocarcinoma. We conclude that Ep-CAM is immunogenic not only for cancer patients, but also for tumor-free individuals.
Kirman
Irena
I
College of Physicians and Surgeons of Columbia University, Department of Surgery, 630 West, 168th Street, New York, New York 10032, USA. ik139@columbia.edu
Jenkins
Dareema
D
Fowler
Ryan
R
Whelan
Richard L
RL
D000230:Adenocarcinoma / Q000097:blood* / Q000188:drug therapy; D000818:Animals; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D000912:Antibodies, Neoplasm / Q000097:blood*; D000951:Antigens, Neoplasm / Q000097:blood*; D015153:Blotting, Western; D017252:CD3 Complex / Q000097:blood*; D016022:Case-Control Studies; D015815:Cell Adhesion Molecules / Q000097:blood*; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000097:blood* / Q000188:drug therapy; D004195:Disease Models, Animal; D000071858:Epithelial Cell Adhesion Molecule; D005260:Female; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008875:Middle Aged
D000911:Antibodies, Monoclonal; D000912:Antibodies, Neoplasm; D000951:Antigens, Neoplasm; D017252:CD3 Complex; D015815:Cell Adhesion Molecules; D000071858:Epithelial Cell Adhesion Molecule