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Flt3 ligand expands bona fide innate lymphoid cell precursors in vivo.

ABSTRACT: A common helper-like innate lymphoid precursor (CHILP) restricted to the innate lymphoid cells (ILC) lineage has been recently characterized. While specific requirements of transcription factors for CHILPs development has been partially described, their ability to sense cytokines and react to peripheral inflammation remains unaddressed. Here, we found that systemic increase in Flt3L levels correlated with the expansion of Lineage (Lin)neg?4?7+ precursors in the adult murine bone marrow. Expanded Linneg?4?7+ precursors were bona fide CHILPs as seen by their ability to differentiate into all helper ILCs subsets but cNK in vivo. Interestingly, Flt3L-expanded CHILPs transferred into lymphopenic mice preferentially reconstituted the small intestine. While we did not observe changes in serum Flt3L during DSS-induced colitis in mice or plasma from inflammatory bowel disease (IBD) patients, elevated Flt3L levels were detected in acute malaria patients. Interestingly, while CHILP numbers were stable during the course of DSS-induced colitis, they expanded following increased serum Flt3L levels in malaria-infected mice, hence suggesting a role of the Flt3L-ILC axis in malaria. Collectively, our results indicate that Flt3L expands CHILPs in the bone marrow, which might be associated with specific inflammatory conditions.

SUBMITTER: Parigi SM

PROVIDER: S-EPMC5760642 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Flt3 ligand expands bona fide innate lymphoid cell precursors in vivo.

Parigi Sara M SM Czarnewski Paulo P Das Srustidhar S Steeg Christiane C Brockmann Leonie L Fernandez-Gaitero Sara S Yman Victor V Forkel Marianne M Höög Charlotte C Mjösberg Jenny J Westerberg Lisa L Färnert Anna A Huber Samuel S Jacobs Thomas T Villablanca Eduardo J EJ

Scientific reports 20180109 1

A common helper-like innate lymphoid precursor (CHILP) restricted to the innate lymphoid cells (ILC) lineage has been recently characterized. While specific requirements of transcription factors for CHILPs development has been partially described, their ability to sense cytokines and react to peripheral inflammation remains unaddressed. Here, we found that systemic increase in Flt3L levels correlated with the expansion of Lineage (Lin)<sup>neg</sup>α4β7<sup>+</sup> precursors in the adult murine ...[more]

PMID: 29317685

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Flt3 ligand expands bona fide innate lymphoid cell precursors in vivo.

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Flt3 ligand expands bona fide innate lymphoid cell precursors in vivo.

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