title: B7-H1 (PD-L1, CD274) suppresses host immunity in T-cell lymphoproliferative disorders.
abstract: Stromal elements present within the tumor microenvironment may suppress host immunity and promote the growth of malignant lymphocytes in B cell-derived non-Hodgkin lymphoma (NHL). In contrast, little is known about the microenvironment's role in T cell-derived NHL. B7-H1 (PD-L1, CD274), a member of the B7 family of costimulatory/co-inhibitory ligands expressed by both malignant cells and stromal cells within the tumor microenvironment, has emerged as an important immune modulator capable of suppressing host immunity. Therefore, B7-H1 expression and function were analyzed in cutaneous and peripheral T-cell NHL. B7-H1 was expressed by tumor cells, monocytes, and monocyte-derived cells within the tumor microenvironment in T-cell NHL and was found to inhibit T-cell proliferation and promote the induction of FoxP3(+) regulatory T cells. Collectively, the data presented provide the first evidence implicating B7-H1 in the suppression of host immunity in T-cell lymphoproliferative disorders and suggest that the targeting of B7-H1 may represent a novel therapeutic approach.
authors: Division of Hematology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors: Ryan A
authors: RA
authors: Wilcox
authors: Andrew L
authors: AL
authors: Feldman
authors: David A
authors: DA
authors: Wada
authors: Zhi-Zhang
authors: ZZ
authors: Yang
authors: Nneka I
authors: NI
authors: Comfere
authors: Haidong
authors: H
authors: Dong
authors: Eugene D
authors: ED
authors: Kwon
authors: Anne J
authors: AJ
authors: Novak
authors: Svetomir N
authors: SN
authors: Markovic
authors: Mark R
authors: MR
authors: Pittelkow
authors: Thomas E
authors: TE
authors: Witzig
authors: Stephen M
authors: SM
authors: Ansell
mesh_terms: D015703:Antigens, CD / Q000096:biosynthesis / Q000276:immunology*; D060890:B7-H1 Antigen; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D051858:Forkhead Transcription Factors; D015972:Gene Expression Regulation, Neoplastic / Q000276:immunology*; D006801:Humans; D007108:Immune Tolerance; D008232:Lymphoproliferative Disorders / Q000276:immunology* / Q000378:metabolism / Q000628:therapy; D009000:Monocytes / Q000276:immunology / Q000378:metabolism; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000378:metabolism
chemical_list: D015703:Antigens, CD; D060890:B7-H1 Antigen; C423236:CD274 protein, human; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors