title: Partial purification of murine tumor-associated peptide epitopes common to histologically distinct tumors, melanoma and sarcoma, that are presented by H-2Kb molecules and recognized by CD8+ tumor-infiltrating lymphocytes.
abstract: The B16/BL6 melanoma is a relatively nonimmunogenic tumor expressing low levels of MHC class I molecules. BL6 clones expressing transfected H-2Kb class I molecules were, by contrast, highly immunogenic in immunocompetent mice. Tumor-infiltrating lymphocytes (TILs) generated from the H-2Kb+ BL6 lesions (Thy 1.2+, CD8+, CD4-) efficiently lysed H-2Kb+ melanoma (CL8-1 and 2Kb38) and the H-2Kb+ nonrelated 3-methylcholanthrene (MCA)-105 sarcoma, but not the H-2Kb- parental melanoma BL6-8. This strongly suggests that CL8-1, 2Kb38, and MCA-105 express identical or cross-reactive T cell epitopes recognized by CL8-1 TILs in the context of the H-2Kb class I allele. To identify the T cell epitopes, peptides were acid-eluted from various cells, and fractionated by HPLC. Five HPLC fractions (F1mel-F5mel) of 70 tested contained peptides derived from H-2Kb+ CL8-1 melanoma (but not H-2Kb- melanomas) that were capable of conferring susceptibility to CL8-1 TIL lysis on H-2b-expressing target cells (EL4, C1R.Kb), but not on H-2d-expressing P815 target cells. CL8-1 TILs failed to recognize peptides derived from H-2Kb+ nonmelanoma targets such as EL4 or normal B6 splenocytes. Interestingly, CL8-1 TILs appeared to recognize peptide species contained in two HPLC fractions derived from the MCA-105 sarcoma (F1sar and F5sar). Conversely, TILs derived from MCA-105 lesions recognized MCA-105 and CL8-1 tumor cells, as well as F5mel and F5sar peptides presented by EL4 targets. These data support common murine tumor-associated peptide epitopes presented by H-2Kb and recognized by CD8+ CTLs derived from histologically distinct tumors, melanoma and sarcoma.
authors.affiliation: Department of Surgery, University of Pittsburgh School of Medicine, PA.
authors.forename: T
authors.initials: T
authors.lastname: Itoh
authors.forename: W J
authors.initials: WJ
authors.lastname: Storkus
authors.forename: E
authors.initials: E
authors.lastname: Gorelik
authors.forename: M T
authors.initials: MT
authors.lastname: Lotze
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology*; D000951:Antigens, Neoplasm / Q000737:chemistry / Q000276:immunology*; D016827:CD8 Antigens / Q000032:analysis; D003602:Cytotoxicity, Immunologic; D000939:Epitopes; D005260:Female; D006183:H-2 Antigens / Q000276:immunology*; D016246:Lymphocytes, Tumor-Infiltrating / Q000276:immunology*; D008546:Melanoma, Experimental / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D010455:Peptides / Q000276:immunology; D012513:Sarcoma, Experimental / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology
chemical_list: D000951:Antigens, Neoplasm; D016827:CD8 Antigens; D000939:Epitopes; D006183:H-2 Antigens; D010455:Peptides