title: Distinct effects of human glioblastoma immunoregulatory molecules programmed cell death ligand-1 (PDL-1) and indoleamine 2,3-dioxygenase (IDO) on tumour-specific T cell functions.
abstract: Immunotherapy is a promising new treatment for patients suffering from glioma, in particular glioblastoma multiforme (GBM). However, tumour cells use different mechanisms to escape the immune responses induced by the treatment. As many other tumours, gliomas express or secrete several immunosuppressive molecules that regulate immune cell functions. In this study, we first analysed FasL, HLA-G, IDO, PDL-1 and TGF-beta1, -beta2 and -beta3 expression by transcriptomic microarray analysis in a series of 20 GBM samples and found respectively 15%, 60%, 85%, 30%, 70%, 80% and 35% of positive specimens. mRNA expression was then confirmed in 10 GBM primary cell lines and 2 immortalised cell lines U251 and U87MG. Furthermore, the protein expression of PDL-1, IDO activity and TGF-beta2 secretion were found on most of the untreated GBM primary cell lines. Remarkably, treatment with IFN-gamma increased the PDL-1 cell surface expression and the IDO activity, but reduced the TGF-beta2 secretion of GBM cell lines. We finally analysed the immunosuppressive effects of IDO, PDL-1 and TGF-beta1-3 by measuring IFN-gamma production and cell cytotoxicity activity of tumour antigen-specific T cells. PDL-1 partially affected the IFN-gamma production of antigen-specific T cells in response to GBM primary cell lines, and IDO inhibited lymphocyte proliferation induced by lectins. None of these molecules directly affected the T cell cytotoxicity function. Due to the functional role of PDL-1 and IDO molecules expressed by GBM cells, one could expect that blocking these molecules in the immunotherapy strategies would reinforce the efficiency of these treatments of GBM patients.
authors.affiliation: Département de Biologie, Centre Eugène Marquis, Rennes, France. t.avril@rennes.fnclcc.fr
authors.forename: Tony
authors.initials: T
authors.lastname: Avril
authors.forename: Stéphan
authors.initials: S
authors.lastname: Saikali
authors.forename: Elodie
authors.initials: E
authors.lastname: Vauleon
authors.forename: Anne
authors.initials: A
authors.lastname: Jary
authors.forename: Abderrahmane
authors.initials: A
authors.lastname: Hamlat
authors.forename: Marie
authors.initials: M
authors.lastname: De Tayrac
authors.forename: Jean
authors.initials: J
authors.lastname: Mosser
authors.forename: Véronique
authors.initials: V
authors.lastname: Quillien
mesh_terms: D015703:Antigens, CD / Q000378:metabolism* / Q000494:pharmacology; D000951:Antigens, Neoplasm / Q000378:metabolism*; D060890:B7-H1 Antigen; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D003602:Cytotoxicity, Immunologic / Q000187:drug effects / Q000276:immunology; D053222:Fas Ligand Protein / Q000235:genetics / Q000378:metabolism; D005434:Flow Cytometry / Q000379:methods; D020869:Gene Expression Profiling / Q000379:methods; D005786:Gene Expression Regulation / Q000187:drug effects; D005909:Glioblastoma / Q000276:immunology* / Q000473:pathology*; D006680:HLA Antigens / Q000235:genetics / Q000378:metabolism; D015789:HLA-A2 Antigen / Q000378:metabolism; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000235:genetics / Q000378:metabolism; D006801:Humans; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase / Q000378:metabolism* / Q000494:pharmacology; D007371:Interferon-gamma / Q000378:metabolism / Q000494:pharmacology; D037102:Lectins / Q000494:pharmacology; D058965:MART-1 Antigen; D009363:Neoplasm Proteins / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D012333:RNA, Messenger / Q000378:metabolism; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D053781:Transforming Growth Factor beta2 / Q000378:metabolism
chemical_list: D015703:Antigens, CD; D000951:Antigens, Neoplasm; D060890:B7-H1 Antigen; C423236:CD274 protein, human; D053222:Fas Ligand Protein; D006680:HLA Antigens; D015789:HLA-A2 Antigen; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase; D037102:Lectins; D058965:MART-1 Antigen; C548667:MLANA protein, human; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D053781:Transforming Growth Factor beta2; D007371:Interferon-gamma