title: T-cell immune function in tumor, skin, and peripheral blood of advanced stage melanoma patients: implications for immunotherapy.
abstract: OBJECTIVE
  To predict the potential antitumor effect of antigen-specific T cells in melanoma patients, we investigated T-cell effector function in relation to tumor-escape mechanisms.
  
  
  METHODS
  CD8(+) T cells isolated from tumor, adjacent normal skin, and peripheral blood of 17 HLA-A2(+) patients with advanced-stage melanoma were analyzed for their antigen specificity and effector function against melanocyte differentiation antigens MART-1, gp100, and tyrosinase by using HLA-A2/peptide tetramers and functional assays. In addition, the presence of tumor-escape mechanisms PD-L1/PD-1 pathway, FoxP3 and loss of HLA or melanocyte differentiation antigens, both required for tumor cell recognition and killing, were studied.
  
  
  RESULTS
  Higher percentages of melanocyte antigen-specific CD8(+) T cells were found in the melanoma tissues as compared with adjacent normal skin and peripheral blood. Functional analysis revealed 2 important findings: (i) in 5 of 17 patients, we found cytokine production after specific peptide stimulation by tumor-infiltrating lymphocytes (TIL), not by autologous peripheral blood lymphocytes (PBL); (ii) CD8(+) T cells from 7 of 17 patients did not produce cytokines after specific stimulation, which corresponded with significant loss of tumor HLA-A2 expression. The presence of other tumor-escape mechanisms did not correlate to T-cell function.
  
  
  CONCLUSIONS
  Our data show that functional T-cell responses could be missed when only PBL and not TIL are evaluated, emphasizing the importance of TIL analysis for immunomonitoring. Furthermore, loss of tumor HLA-A2 may explain the lack of T-cell functionality. These findings have important implications for selecting melanoma patients who may benefit from immunotherapy.
authors.affiliation: Departments of Dermatology, The Netherlands Institute for Pigment Disorders, Academic Medical Center, University of Amsterdam, The Netherlands.
authors.forename: Esther P M
authors.initials: EP
authors.lastname: Tjin
authors.forename: Debby
authors.initials: D
authors.lastname: Konijnenberg
authors.forename: Gabrielle
authors.initials: G
authors.lastname: Krebbers
authors.forename: Henk
authors.initials: H
authors.lastname: Mallo
authors.forename: Jan W
authors.initials: JW
authors.lastname: Drijfhout
authors.forename: Kees L M C
authors.initials: KL
authors.lastname: Franken
authors.forename: Chantal M A M
authors.initials: CM
authors.lastname: van der Horst
authors.forename: Jan D
authors.initials: JD
authors.lastname: Bos
authors.forename: Omgo E
authors.initials: OE
authors.lastname: Nieweg
authors.forename: Bin B R
authors.initials: BB
authors.lastname: Kroon
authors.forename: John B A G
authors.initials: JB
authors.lastname: Haanen
authors.forename: Cornelis J M
authors.initials: CJ
authors.lastname: Melief
authors.forename: Florry A
authors.initials: FA
authors.lastname: Vyth-Dreese
authors.forename: Rosalie M
authors.initials: RM
authors.lastname: Luiten
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D060890:B7-H1 Antigen / Q000096:biosynthesis; D015496:CD4-Positive T-Lymphocytes; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis; D003602:Cytotoxicity, Immunologic; D005260:Female; D051858:Forkhead Transcription Factors / Q000096:biosynthesis; D015789:HLA-A2 Antigen / Q000096:biosynthesis / Q000276:immunology; D006801:Humans; D007167:Immunotherapy; D008213:Lymphocyte Activation; D016246:Lymphocytes, Tumor-Infiltrating / Q000276:immunology*; D058965:MART-1 Antigen / Q000276:immunology; D008297:Male; D008545:Melanoma / Q000097:blood / Q000276:immunology* / Q000473:pathology / Q000628:therapy; D008875:Middle Aged; D014442:Monophenol Monooxygenase / Q000276:immunology; D012867:Skin / Q000276:immunology*; D019139:Tumor Escape; D058951:gp100 Melanoma Antigen / Q000276:immunology
chemical_list: D060890:B7-H1 Antigen; C423236:CD274 protein, human; D016207:Cytokines; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; D015789:HLA-A2 Antigen; D058965:MART-1 Antigen; D058951:gp100 Melanoma Antigen; D014442:Monophenol Monooxygenase