CCL22-producing CD8α- myeloid dendritic cells mediate regulatory T cell recruitment in response to G-CSF treatment Article uri icon

abstract

  • G-CSF prevents type 1 diabetes in the NOD mouse by promoting the local recruitment of T regulatory cells (Tregs). This is an indirect effect because adoptive transfer of G-CSF-induced tolerogenic dendritic cells (DCs) promotes Treg accumulation. However, the identity of the particular DC subset and the molecule(s) mediating this effect remain unknown. We demonstrate in this study that the adoptive transfer of CD11chighCD8α- DCs isolated from pegylated G-CSF (pegG-CSF) recipients, but not that of other DC subtypes, enhanced the pancreatic recruitment of CD4 CD25 Foxp3 Tregs, which generated increased amounts of TGF-β. Likewise, only CD11chighCD8α- DCs from pegG-CSF recipients secreted the chemokine CCL22 at levels that effectively attracted Tregs. PegG-CSF was more efficient at enhancing the synthesis of CCL22 by CD11chighCD8α- DCs from the pancreatic lymph nodes compared with those from the spleen. Accordingly, CD11c highCD8α- DCs from the pancreatic lymph nodes of pegG-CSF recipients were more efficient than their splenic counterparts in the recruitment of Tregs upon adoptive transfer. Predictably, CD11c highCD8α- DCs failed to recruit these Tregs both in vivo and in vitro following intracellular neutralization of CCL22. These data assign a key role to CD8α- DCs and CCL22 in Treg recruitment in the protection of NOD mice against type 1 diabetes following the treatment with G-CSF. Copyright © 2013 by The American Association of Immunologists, Inc.
  • G-CSF prevents type 1 diabetes in the NOD mouse by promoting the local recruitment of T regulatory cells (Tregs). This is an indirect effect because adoptive transfer of G-CSF-induced tolerogenic dendritic cells (DCs) promotes Treg accumulation. However, the identity of the particular DC subset and the molecule(s) mediating this effect remain unknown. We demonstrate in this study that the adoptive transfer of CD11chighCD8α- DCs isolated from pegylated G-CSF (pegG-CSF) recipients, but not that of other DC subtypes, enhanced the pancreatic recruitment of CD4%2bCD25 %2bFoxp3%2b Tregs, which generated increased amounts of TGF-β. Likewise, only CD11chighCD8α- DCs from pegG-CSF recipients secreted the chemokine CCL22 at levels that effectively attracted Tregs. PegG-CSF was more efficient at enhancing the synthesis of CCL22 by CD11chighCD8α- DCs from the pancreatic lymph nodes compared with those from the spleen. Accordingly, CD11c highCD8α- DCs from the pancreatic lymph nodes of pegG-CSF recipients were more efficient than their splenic counterparts in the recruitment of Tregs upon adoptive transfer. Predictably, CD11c highCD8α- DCs failed to recruit these Tregs both in vivo and in vitro following intracellular neutralization of CCL22. These data assign a key role to CD8α- DCs and CCL22 in Treg recruitment in the protection of NOD mice against type 1 diabetes following the treatment with G-CSF. Copyright © 2013 by The American Association of Immunologists, Inc.

publication date

  • 2013-01-01