title: A T-helper cell epitope overlaps a major B-cell epitope in human papillomavirus type 18 E2 protein.
abstract: Cultivated CD4+ T-helper cells from two patients with cervical adenocarcinoma showed responses to a peptide EKTGILTVTYHSETQRTK derived from an E2 protein of human papillomavirus type 18 (HPV 18), but not to a corresponding HPV 16 peptide (HKSAIVTLTYDSEWQRDQ). Serum antibodies in the HPV 18 peptide were also demonstrated in these patients. The GILT motif resembles a common pattern present in many T-cell epitopes, and is located at the beginning of an 11-amino acid-long A-helix structure close to the carboxyterminal end of HPV 18 E2. We conclude that two epitopes (a T-helper cell epitope and a B-cell epitope) overlap in the HPV 18 E2.
mesh_terms: D000595:Amino Acid Sequence; D000914:Antibodies, Viral / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D004268:DNA-Binding Proteins; D000939:Epitopes; D015234:HLA-A Antigens / Q000378:metabolism; D006684:HLA-DR Antigens / Q000378:metabolism; D006801:Humans; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D009856:Oncogene Proteins, Viral / Q000276:immunology*; D010455:Peptides / Q000276:immunology; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D004268:DNA-Binding Proteins; C054855:E2 protein, Human papillomavirus type 16; D000939:Epitopes; D015234:HLA-A Antigens; D006684:HLA-DR Antigens; D009856:Oncogene Proteins, Viral; D010455:Peptides; D011948:Receptors, Antigen, T-Cell; C069102:oncogene protein E2, Human papillomavirus type 18