IL-17A Controls IL-17F Production and Maintains Blood Neutrophil Counts in Mice

Content Provider	Scilit
Author	von Vietinghoff, Sibylle Ley, Klaus
Copyright Year	2009
Description	G-CSF, its receptor, and IL-17 receptor A (IL-17RA) are all required to maintain baseline neutrophil counts in mice. In this study, we tested whether IL-17F could compensate and maintain baseline neutrophil counts in the absence of IL-17A. Unlike the reduced neutrophil counts found in IL-17RA-deficient mice, neutrophil counts were mildly increased in IL-17A-deficient $(Il17a^{−/−}$) animals. There was no evidence for infection or altered neutrophil function. Plasma G-CSF and IL-17F levels were elevated in $Il17a^{−/−}$ compared with wild-type mice. IL-17F was mainly produced in the spleen and mesenteric lymph nodes, but IL-23 was unaltered in $Il17a^{−/−}$ mice. Instead, $Il17a^{−/−}$ splenocytes differentiated with IL-6, TGF-β, and IL-23 ex vivo produced significantly more IL-17F in response to IL-23 than wild-type cells. Adding rIL-17A to $Il17a^{−/−}$ splenocyte cultures reduced IL-17F mRNA and protein secretion. These effects were also observed in wild-type but not IL-17RA-deficient cells. We conclude that IL-17A mediated suppression of IL-17F production and secretion requires IL-17RA and is relevant to maintain the normal set point of blood neutrophil counts in vivo.
Ending Page	873
Page Count	9
Starting Page	865
ISSN	00221767
e-ISSN	15506606
DOI	10.4049/jimmunol.0804080
Alternate Webpage(s)	http://www.jimmunol.org/content/183/2/865.full.pdf
Journal	The Journal of Immunology
Issue Number	2
Volume Number	183
Language	English
Publisher	The American Association of Immunologists
Publisher Date	2009-07-15
Access Restriction	Open
Subject Keyword	Il-17f
Content Type	Text
Resource Type	Article
Subject	Immunology and Allergy Immunology