title: Interleukin-10 dose-dependent regulation of CD4+ and CD8+ T cell-mediated graft-versus-host disease.
abstract: BACKGROUND
  Endogenous interleukin (IL)-10 production has been associated with the lack of graft-versus-host disease (GVHD) in human recipients of MHC-disparate donor grafts. Paradoxically, we have shown that the exogenous administration of high doses (30 microg/dose) of IL-10 to murine recipients of MHC-disparate grafts accelerates GVHD lethality.
  
  
  METHODS
  The effects of IL-10 on GVHD mediated by either CD4+ or CD8+ T cells was examined in studies involving exogenous IL-10 administration or the infusion of T cells from IL-10-deficient (-/-) donor mice. The role of interferon (IFN)-gamma on IL-10-induced GVHD acceleration was studied using IFN-gamma-deficient (-/-) donor mice or neutralizing monoclonal antibody.
  
  
  RESULTS
  IL-10 was found to have a dose-dependent effect on the GVHD lethality mediated by either CD4+ or CD8+ T cells. High doses of exogenous IL-10 accelerated GVHD lethality. IFN-gamma release was not responsible for the IL-10 facilitation of GVHD lethality. Paradoxically, low doses of IL-10 protected mice against GVHD lethality. The GVHD protective effect of the bioavailability of small amounts of IL-10 was confirmed by demonstrating that the infusion of T cells from IL-10 -/- donors accelerated GVHD lethality.
  
  
  CONCLUSIONS
  The results suggest that IL-10 has a dose-dependent effect on the GVHD lethality mediated by CD4+ or CD8+ T cells, such that high doses accelerate lethality, while low amounts of bioavailable IL-10 are protective.
authors.affiliation: University of Minnesota Cancer Center and the Department of Pediatrics, Minneapolis 55455, USA.
authors.forename: B R
authors.initials: BR
authors.lastname: Blazar
authors.forename: P A
authors.initials: PA
authors.lastname: Taylor
authors.forename: A
authors.initials: A
authors.lastname: Panoskaltsis-Mortari
authors.forename: S K
authors.initials: SK
authors.lastname: Narula
authors.forename: S R
authors.initials: SR
authors.lastname: Smith
authors.forename: M G
authors.initials: MG
authors.lastname: Roncarolo
authors.forename: D A
authors.initials: DA
authors.lastname: Vallera
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D004306:Dose-Response Relationship, Immunologic; D015536:Down-Regulation; D006086:Graft vs Host Disease / Q000276:immunology*; D006801:Humans; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000378:metabolism; D016753:Interleukin-10 / Q000008:administration & dosage* / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL
chemical_list: D016753:Interleukin-10; D007371:Interferon-gamma