Two SHIPs passing in the middle of the immune system.
Immunity requires a complex, multiscale system of molecules, cells, and cytokines. In this issue of the European Journal of Immunology, Collazo et al. [Eur. J. Immunol. 2012. 42: 1785-1796] provide evidence that links the lipid phosphatase SHIP1 with the coordination of interactions between regulatory T (Treg) cells and myeloid-derived suppressor cells (MDSCs). Using conditional knockouts of SHIP1 in either the myeloid or T-cell-lineage of mice, the authors show that the regulated development of Treg cells is controlled directly by cell-intrinsic SHIP1, and indirectly by extrinsic SHIP1 control of an unknown myeloid cell. Regulation of MDSCs is also determined by SHIP1 in an extrinsic manner, again via an as-yet-unknown myeloid cell. Furthermore, this extrinsic control of Treg cells and MDSCs is mediated in part by increased production of G-CSF, a growth factor critical for the production of neutrophils, in SHIP1-deficient mice. Thus, a physiologically important implication of this report is the collaboration between the innate and adaptive immune systems in fine tuning of Treg cells as discussed in this commentary.
Department of Pediatrics and Cell & Molecular Biology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA. s-corey@northwestern.edu
Seth J
SJ
Corey
Hrishikesh M
HM
Mehta
Paul L
PL
Stein
D056704:Adaptive Immunity / Q000276:immunology; D000818:Animals; D018507:Gene Expression Regulation, Developmental / Q000276:immunology; D016179:Granulocyte Colony-Stimulating Factor / Q000276:immunology; D007113:Immunity, Innate / Q000276:immunology; D000072181:Inositol Polyphosphate 5-Phosphatases; D051379:Mice; D022423:Myeloid Cells / Q000276:immunology*; D000072183:Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases; D010744:Phosphoric Monoester Hydrolases / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
D016179:Granulocyte Colony-Stimulating Factor; D010744:Phosphoric Monoester Hydrolases; D000072181:Inositol Polyphosphate 5-Phosphatases; C000606433:Inpp5d protein, mouse; D000072183:Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases