title: T-cell receptor BV gene usage in colorectal carcinoma patients immunised with recombinant Ep-CAM protein or anti-idiotypic antibody.
abstract: The tumour-associated antigen, Ep-CAM, is over-expressed in colorectal carcinoma (CRC). In the present study, a recombinant Ep-CAM protein or a human anti-idiotypic antibody (anti-Id) mimicking Ep-CAM, either alone or in combination, was used for vaccination of CRC patients (n=9). GM-CSF was given as an adjuvant cytokine. A cellular immune response was assessed by measuring anti-Ep-CAM lymphoproliferation, IFN-gamma production (ELISPOT) and by analysing the TCR BV gene usage within the CD4+ and CD8+ T-cell subsets followed by CDR3 fragment analysis. A proliferative and/or IFN-gamma T-cell response was induced against the Ep-CAM protein in eight out of nine patients, and against Ep-CAM-derived peptides in nine out of nine patients. Analysis of the TCR BV gene usage showed a significantly higher usage of BV12 family in CD4+ T cells of patients both before and after immunisation than in those of healthy control donors (p<0.05). In the CD8+ T-cell subset, a significant (p<0.05) increase in the BV19 usage was noted in patients after immunisation. In individual patients, a number of TCR BV gene families in both CD4+ and CD8+ T cells were over-expressed mainly in post-immunisation samples. Analysis of the CDR3 length polymorphism revealed a higher degree of clonality in post-immunisation samples than in pre-immunisation samples. In vitro stimulation with Ep-CAM protein confirmed the expansion of anti-Ep-CAM T-cell clones. The results indicate that immunisation with the Ep-CAM protein and/or anti-Id entails the induction of an anti-Ep-CAM T-cell response in CRC patients, and suggest that BV19+ CD8+ T cells might be involved in a vaccine-induced immune response.
authors.affiliation: Immune and Gene Therapy Laboratory, Department of Oncology (Radiumhemmet), Karolinska Institute, Stockholm, Sweden.
authors.forename: Szilvia
authors.initials: S
authors.lastname: Mosolits
authors.forename: Katja
authors.initials: K
authors.lastname: Markovic
authors.forename: Jan
authors.initials: J
authors.lastname: Fagerberg
authors.forename: Jan-Erik
authors.initials: JE
authors.lastname: Frödin
authors.forename: Mohammad-Reza
authors.initials: MR
authors.lastname: Rezvany
authors.forename: Shahryar
authors.initials: S
authors.lastname: Kiaii
authors.forename: Håkan
authors.initials: H
authors.lastname: Mellstedt
authors.forename: Mahmood
authors.initials: M
authors.lastname: Jeddi-Tehrani
mesh_terms: D000328:Adult; D000368:Aged; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology*; D000951:Antigens, Neoplasm / Q000276:immunology*; D015815:Cell Adhesion Molecules / Q000276:immunology*; D015179:Colorectal Neoplasms / Q000276:immunology*; D022801:Complementarity Determining Regions; D000071858:Epithelial Cell Adhesion Molecule; D005260:Female; D019674:Genes, T-Cell Receptor beta; D006801:Humans; D007114:Immunization; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D014614:Vaccines, Synthetic / Q000276:immunology*
chemical_list: D000888:Antibodies, Anti-Idiotypic; D000951:Antigens, Neoplasm; D015815:Cell Adhesion Molecules; D022801:Complementarity Determining Regions; C499379:EPCAM protein, human; D000071858:Epithelial Cell Adhesion Molecule; D014614:Vaccines, Synthetic