title: Cytotoxic T lymphocytes that recognize decameric peptide sequences of retinoblastoma binding protein 1 (RBP-1) associated with human breast cancer.
abstract: Retinoblastoma binding protein 1 (RBP-1) is a 143-kDa nuclear phosphoprotein that promotes cell growth by inhibiting the product of retinoblastoma tumour suppressor gene (pRB). We recently found that RBP-1 contains KASIFLK, a heptameric peptide (250-256) recognized by human antibodies and overexpressed by breast cancer cells. In the present study, we demonstrate that human T-cells stimulated with RBP-1 decameric peptides containing KASIFLK can kill human breast cancer cells. These decamers, GLQKASIFLK (247-256) and KASIFLKTRV (250-259), have anchor motifs for both HLA-A2 and HLA-A3. Peripheral blood lymphocytes from 41 normal donors were stimulated by these peptides in culture media containing 15 IU ml(-1) interleukin-2, 25 IU ml(-1) interleukin-7 and 500 IU ml(-1) granulocyte-macrophage colony-stimulating factor. Cytotoxic activity of the T-cells was assessed against autologous B lymphoblastoid cells pulsed with each peptide. Stimulation by GLQKASIFLK generated specific cytotoxic T lymphocyte (CTL) lines from HLA-A2, A3 donors, HLA-A2 donors and HLA-A3 donors. Stimulation with KASIFLKTRV generated specific CTL lines from HLA-A2 donors. No HLA-A2-, A3 CTL line showed specific cytotoxicity against these target cells. These CTL lines were also cytotoxic against HLA-A2 and HLA-A3 breast cancer cells but not against normal fibroblastoid cell lines, normal epidermal cell lines, or a melanoma cell line. RBP-1 peptide antigens may be of clinical significance as a potential peptide vaccine against human breast cancer.
authors.affiliation: Department of Biotechnology Sciences, John Wayne Cancer Institute, Santa Monica, CA 90404, USA.
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: J
authors.initials: J
authors.lastname: Cao
authors.forename: D S
authors.initials: DS
authors.lastname: Hoon
authors.forename: R F
authors.initials: RF
authors.lastname: Irie
mesh_terms: D000595:Amino Acid Sequence; D001943:Breast Neoplasms / Q000276:immunology* / Q000378:metabolism*; D002352:Carrier Proteins / Q000737:chemistry / Q000502:physiology*; D003601:Cytotoxicity Tests, Immunologic; D003602:Cytotoxicity, Immunologic; D015234:HLA-A Antigens; D006801:Humans; D008213:Lymphocyte Activation; D016160:Retinoblastoma Protein / Q000737:chemistry / Q000502:physiology*; D013602:T-Lymphocytes, Cytotoxic / Q000502:physiology*; D014407:Tumor Cells, Cultured
chemical_list: D002352:Carrier Proteins; D015234:HLA-A Antigens; D016160:Retinoblastoma Protein