title: Allo-restricted CTLs generated by coculturing of PBLs and autologous monocytes loaded with allogeneic peptide/HLA/IgG1-Fc fusion protein.
abstract: The graft-versus-leukemia effect of allogeneic marrow transplantation suggests the dramatic effect of the allogeneic T cell to eradicate malignant disease. Preparation and adoptive transfusion of tumor-specific T cells from HLA-mismatched donors might be expected to circumvent CTL tolerance to the tumor. In this study, a soluble, divalent HLA-A2 molecule was constructed with the Fc part of human IgG1 and was pulsed with a peptide related to melanoma tyrosinase 368-376 [Tyr(368-376) (Tyr)] to form the Tyr/HLA-A2 dimer, which allowed loading onto monocytes via interaction of the Fc and FcR. The HLA-A2-negative (HLA-A2-ve) monocytes loaded with the Tyr/HLA-A2 dimer acted as allo-APC with copies of a single allogeneic epitope. After coculture of the HLA-A2-ve PBLs and autologous monocytes loaded with the dimer, CD8+ cells in the coculture show an obvious proliferation and increased frequency of Tyr/HLA-A2 tetramer-stained cells. The sorted Tyr/HLA-A2 tetramer-positive CD8+ cells display an elevated cytotoxic activity against HLA-A2-positive melanoma cells expressing tyrosinase endogenously (i.e., SK-Mel-5) but little against tyrosinase-negative melanoma cells (i.e., A375). The coculture of PBLs and autologous monocytes loaded with allogeneic peptide/HLA complexes offers a novel approach to expand allo-restricted, peptide-specific CTLs, which might be a potential arsenal for treatment of patients with malignant disease, if the tumor-related epitope were defined.
authors.affiliation: Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Xiufang
authors.initials: X
authors.lastname: Weng
authors.forename: Shengjun
authors.initials: S
authors.lastname: Lu
authors.forename: Maohua
authors.initials: M
authors.lastname: Zhong
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Liang
authors.forename: Guanxin
authors.initials: G
authors.lastname: Shen
authors.forename: Jianguo
authors.initials: J
authors.lastname: Chen
authors.forename: Xiongwen
authors.initials: X
authors.lastname: Wu
mesh_terms: D000938:Antigen-Presenting Cells / Q000276:immunology; D000951:Antigens, Neoplasm / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D018920:Coculture Techniques; D015789:HLA-A2 Antigen; D006801:Humans; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D007519:Isoantigens; D008214:Lymphocytes / Q000276:immunology*; D008545:Melanoma / Q000276:immunology; D009000:Monocytes / Q000276:immunology*; D010455:Peptides; D011993:Recombinant Fusion Proteins / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology* / Q000276:immunology
chemical_list: D000951:Antigens, Neoplasm; D015789:HLA-A2 Antigen; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D007519:Isoantigens; D010455:Peptides; D011993:Recombinant Fusion Proteins