title: Dendritic cells with TGF-β1 and IL-2 differentiate naive CD4+ T cells into alloantigen-specific and allograft protective Foxp3+ regulatory T cells.
abstract: BACKGROUND
  Naturally occurring, thymic-derived Foxp3+CD25+CD4+ regulatory T cells (nTregs) are pivotal for the maintenance of self-tolerance. nTregs, however, are sparse and lack alloantigen specificity, and these properties pose challenges for their use in clinical transplantation.
  
  
  METHODS
  We established mixed leukocyte reaction (MLR) with dendritic cells (DCs) as stimulators and CD4+ T cells as responders and supplemented the MLR with IL-2 and TGF-β1 and investigated whether DCs+IL-2+TGF-β1 differentiate the polyclonal CD4+ cells into alloantigen-specific and allograft protective Tregs.
  
  
  RESULTS
  We found a greater than a 10-fold increase in Foxp3+CD25+ subpopulation (P<0.01) following stimulation of BALB/c CD4+ cells with C57BL/6 (B6) CD11c+ DCs+IL-2+TGF-β1 in the MLR. Levels of TGF-β1 messenger RNA (mRNA) (P=0.01) and the ratios of TGF-β1 mRNA to granzyme B mRNA (P=0.0003) and Foxp3 mRNA to granzyme B mRNA (P<0.01) were higher in alloantigen-induced Tregs (alloTregs) compared with nTregs. alloTregs suppressed MLR at a 16:1 responder to suppressor ratio, whereas nTregs suppressed at 4:1. Suppression by alloTregs was alloantigen specific and was observed at the level of responder cells and at the level of stimulator cells. In a fully H-2-mismatched, nonlymphopenic, immunocompetent mouse islet transplantation model, alloTregs but not nTregs prolonged survival of islet allografts without any other immunosuppressive therapy (P=0.0003), and the protection was alloantigen specific.
  
  
  CONCLUSIONS
  A combination of CD11c+ DCs, IL-2, and TGF-β1 may help differentiate naive, high abundant CD4+ T into alloantigen-specific and allograft protective Foxp3+Tregs.
authors.affiliation: Division of Nephrology and Hypertension, Department of Medicine, NewYork Presbyterian/Weill Cornell Medical Center, New York, NY, USA.
authors.forename: Hua
authors.initials: H
authors.lastname: Yang
authors.forename: Elaine Y
authors.initials: EY
authors.lastname: Cheng
authors.forename: Vijay K
authors.initials: VK
authors.lastname: Sharma
authors.forename: Mila
authors.initials: M
authors.lastname: Lagman
authors.forename: Christina
authors.initials: C
authors.lastname: Chang
authors.forename: Ping
authors.initials: P
authors.lastname: Song
authors.forename: Ruchuang
authors.initials: R
authors.lastname: Ding
authors.forename: Thangamani
authors.initials: T
authors.lastname: Muthukumar
authors.forename: Manikkam
authors.initials: M
authors.lastname: Suthanthiran
mesh_terms: D000818:Animals; D018845:CD11 Antigens / Q000378:metabolism; D015704:CD4 Antigens / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D002450:Cell Communication / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects* / Q000502:physiology; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000166:cytology* / Q000276:immunology; D003921:Diabetes Mellitus, Experimental / Q000601:surgery; D004195:Disease Models, Animal; D051858:Forkhead Transcription Factors / Q000378:metabolism*; D007376:Interleukin-2 / Q000494:pharmacology*; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism; D016381:Islets of Langerhans Transplantation / Q000379:methods; D007519:Isoantigens / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D012333:RNA, Messenger / Q000378:metabolism; D013311:Streptozocin; D050378:T-Lymphocytes, Regulatory / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology*; D014184:Transplantation, Homologous
chemical_list: D018845:CD11 Antigens; D015704:CD4 Antigens; D051858:Forkhead Transcription Factors; C498833:Foxp3 protein, mouse; D007376:Interleukin-2; D053645:Interleukin-2 Receptor alpha Subunit; D007519:Isoantigens; D012333:RNA, Messenger; D053773:Transforming Growth Factor beta1; D013311:Streptozocin