title: EBV-specific CD8+ T cell reactivation in transplant patients results in expansion of CD8+ type-1 regulatory T cells.
abstract: Posttransplantation lymphoproliferative disorders (PTLD) are life-threatening complications of solid organ transplantation, triggered by EBV infection in chronically immunosuppressed (IS) patients. Our goal is to establish DC-based protocols for adoptive immunotherapy of refractory PTLD, while understanding how the immunosuppressive drug environment may subvert DC-EBV-specific T cell interactions. Type-1 CD8(+) T cells are critical for efficient immune surveillance and control of EBV infection, whereas type-2 or Treg/type-3 responses may provide an environment conductive to disease progression. We have recently reported that chronic IS inhibits DC function in transplant patients. Here, we have analyzed the comparative ability of mature, type-1 polarized DCs (i.e. DC1) generated from quiescent transplant patients or healthy controls, to boost type-1 EBV-specific CD8(+) T cells in vitro. Our results show that unlike healthy controls, where DC1 loaded with MHC class I EBV peptides preferentially reactivate specific type-1 CD8(+) T cells, DC1 generated from transplant patients reactivate EBV-specific CD8(+) T cells that produce both IFN-gamma and IL-10, up-regulate FOXP3 mRNA, and suppress noncognate CD4(+) T-cell proliferation via cell-cell contact. These data support a novel regulatory pathway for anti-EBV T-cell-mediated responses in IS transplant patients, with implications for the design of adoptive immunotherapies in this setting.
authors.affiliation: Thomas E. Starzl Transplantation Institute and Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA.
authors.forename: I
authors.initials: I
authors.lastname: Popescu
authors.forename: C
authors.initials: C
authors.lastname: Macedo
authors.forename: K
authors.initials: K
authors.lastname: Abu-Elmagd
authors.forename: R
authors.initials: R
authors.lastname: Shapiro
authors.forename: Y
authors.initials: Y
authors.lastname: Hua
authors.forename: A W
authors.initials: AW
authors.lastname: Thomson
authors.forename: A E
authors.initials: AE
authors.lastname: Morelli
authors.forename: W J
authors.initials: WJ
authors.lastname: Storkus
authors.forename: D
authors.initials: D
authors.lastname: Metes
mesh_terms: D000914:Antibodies, Viral / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000502:physiology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D016022:Case-Control Studies; D002450:Cell Communication / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000276:immunology / Q000378:metabolism / Q000502:physiology; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000378:metabolism; D004854:Herpesvirus 4, Human / Q000276:immunology*; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology; D016219:Immunotherapy, Adoptive; D007371:Interferon-gamma / Q000235:genetics / Q000378:metabolism; D016753:Interleukin-10 / Q000235:genetics / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology / Q000502:physiology*; D008232:Lymphoproliferative Disorders / Q000276:immunology / Q000517:prevention & control; D016377:Organ Transplantation / Q000009:adverse effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D014181:Transplantation Immunology / Q000276:immunology / Q000502:physiology*
chemical_list: D000914:Antibodies, Viral; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; D007166:Immunosuppressive Agents; D012333:RNA, Messenger; D016753:Interleukin-10; D007371:Interferon-gamma