title: Murine CD4⁺CD25⁻ cells activated in vitro with PMA/ionomycin and anti-CD3 acquire regulatory function and ameliorate experimental colitis in vivo.
abstract: BACKGROUND
  Induced regulatory T (iTreg) lymphocytes show promise for application in the treatment of allergic, autoimmune and inflammatory disorders. iTreg cells demonstrate advantages over natural Treg (nTreg) cells in terms of increased number of starting population and greater potential to proliferate. Different activation methods to generate iTreg cells result in iTreg cells that are heterogeneous in phenotype and mechanisms of suppression. Therefore it is of interest to explore new techniques to generate iTreg cells and to determine their physiological relevance.
  
  
  METHODS
  Using phorbol myristate acetate (PMA)/ionomycin and anti-CD3 activation of CD4⁺CD25⁻ cells we generated in vitro functional CD4⁺CD25⁻ iTreg (TregPMA) cells. Functionality of the generated TregPMA cells was tested in vivo in a mouse model of inflammatory bowel disease (IBD) - CD45RB transfer colitis model.
  
  
  RESULTS
  TregPMA cells expressed regulatory markers and proved to ameliorate the disease phenotype in murine CD45RB transfer colitis model. The body weight loss and disease activity scores for TregPMA treated mice were reduced when compared to diseased control group. Histological assessment of colon sections confirmed amelioration of the disease phenotype. Additionally, cytokine analysis showed decreased levels of proinflammatory colonic and plasma IL-6, colonic IL-1 β and higher levels of colonic IL-17 when compared to diseased control group.
  
  
  CONCLUSIONS
  This study identifies a new method to generate in vitro iTreg cells (TregPMA cells) which physiological efficacy has been demonstrated in vivo.
authors.affiliation: Research and Development, uniQure BV, Meibergdreef 61, 1105 BA, Amsterdam, The Netherlands. a.majowicz@uniqure.com
authors.forename: Anna
authors.initials: A
authors.lastname: Majowicz
authors.forename: Sander
authors.initials: S
authors.lastname: van der Marel
authors.forename: Anje A
authors.initials: AA
authors.lastname: te Velde
authors.forename: Sybren L
authors.initials: SL
authors.lastname: Meijer
authors.forename: Harald
authors.initials: H
authors.lastname: Petry
authors.forename: Sander J
authors.initials: SJ
authors.lastname: van Deventer
authors.forename: Valerie
authors.initials: V
authors.lastname: Ferreira
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001835:Body Weight; D017252:CD3 Complex / Q000276:immunology*; D015704:CD4 Antigens / Q000378:metabolism; D061207:Calcium Ionophores / Q000494:pharmacology*; D003092:Colitis / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D016207:Cytokines / Q000378:metabolism; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism; D015759:Ionomycin / Q000494:pharmacology*; D017493:Leukocyte Common Antigens / Q000378:metabolism; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects* / Q000378:metabolism / Q000637:transplantation*; D013755:Tetradecanoylphorbol Acetate / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D017252:CD3 Complex; D015704:CD4 Antigens; D061207:Calcium Ionophores; D016207:Cytokines; D053645:Interleukin-2 Receptor alpha Subunit; D015759:Ionomycin; C016658:phorbolol myristate acetate; D017493:Leukocyte Common Antigens; D013755:Tetradecanoylphorbol Acetate