title: New monoclonal antibodies against the putative immunosuppressive site of retroviral p15E.
abstract: Both retroviral infections as well as human tumors may cause immunosuppression. One of the factors involved in immunosuppression in patients with squamous cell carcinoma of the head and neck (SCC-HN) is a protein related to the retroviral protein p15E. A conserved, 17-amino acid sequence represents the immunosuppressive epitope of retroviral p15E. In order to study the relationship between SCC-HN associated immunosuppression and retroviral p15E, we produced three new monoclonal antibodies (MAbs; ER-IS1, ER-IS2, and ER-IS5) directed against the immunosuppressive synthetic CKS-17 peptide. These MAbs react with the immunosuppressive peptide (in enzyme-linked immunosorbent assay), with human tumor cell lines (in FACScan analysis), with retroviral p15E (on Western blot), and with cryostat sections of SCC-HN tumor tissue. In addition, the MAbs neutralize the immunosuppressive low molecular weight factors present in sera of patients with SCC-HN. These results show that retroviral p15E and the immunosuppressive factors associated with SCC-HN share a conserved immunosuppressive epitope and that MAbs against this epitope can be used for detection and neutralization of the tumor-associated immunosuppressive protein(s).
authors.affiliation: Department of Immunology, Erasmus University, Rotterdam, The Netherlands.
authors.forename: M S
authors.initials: MS
authors.lastname: Lang
authors.forename: R A
authors.initials: RA
authors.lastname: Oostendorp
authors.forename: P J
authors.initials: PJ
authors.lastname: Simons
authors.forename: W
authors.initials: W
authors.lastname: Boersma
authors.forename: P
authors.initials: P
authors.lastname: Knegt
authors.forename: W
authors.initials: W
authors.lastname: van Ewijk
mesh_terms: D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal; D001666:Binding Sites, Antibody; D015153:Blotting, Western; D002294:Carcinoma, Squamous Cell / Q000473:pathology; D002460:Cell Line; D017124:Conserved Sequence; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000032:analysis; D006258:Head and Neck Neoplasms / Q000473:pathology; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D007165:Immunosuppression Therapy; D007822:Laryngeal Neoplasms / Q000473:pathology; D008175:Lung Neoplasms; D016403:Lymphoma, Large B-Cell, Diffuse; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000276:immunology; D011925:Rauscher Virus / Q000276:immunology; D012190:Retroviridae / Q000276:immunology*; D015682:Retroviridae Proteins, Oncogenic / Q000276:immunology*; D014407:Tumor Cells, Cultured
chemical_list: D000911:Antibodies, Monoclonal; D000939:Epitopes; D010455:Peptides; D015682:Retroviridae Proteins, Oncogenic