title: Neutrophilic granulocytes modulate invariant NKT cell function in mice and humans.
abstract: Invariant NKT (iNKT) cells are a conserved αβTCR(+) T cell population that can swiftly produce large amounts of cytokines, thereby activating other leukocytes, including neutrophilic granulocytes (neutrophils). In this study, we investigated the reverse relationship, showing that high neutrophil concentrations suppress the iNKT cell response in mice and humans. Peripheral Vα14 iNKT cells from spontaneously neutrophilic mice produced reduced cytokines in response to the model iNKT cell Ag α-galactosyl ceramide and expressed lower amounts of the T-box transcription factor 21 and GATA3 transcription factor than did wild-type controls. This influence was extrinsic, as iNKT cell transcription factor expression in mixed chimeric mice depended on neutrophil count, not iNKT cell genotype. Transcription factor expression was also decreased in primary iNKT cells from the neutrophil-rich bone marrow compared with spleen in wild-type mice. In vitro, the function of both mouse and human iNKT cells was inhibited by coincubation with neutrophils. This required cell-cell contact with live neutrophils. Neutrophilic inflammation in experimental peritonitis in mice decreased iNKT cell T-box transcription factor 21 and GATA3 expression and α-galactosyl ceramide-induced cytokine production in vivo. This was reverted by blockade of neutrophil mobilization. Similarly, iNKT cells from the human peritoneal cavity expressed lower transcription factor levels during neutrophilic peritonitis. Our data reveal a novel regulatory axis whereby neutrophils reduce iNKT cell responses, which may be important in shaping the extent of inflammation.
authors.affiliation: Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037, USA.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Wingender
authors.forename: Marcus
authors.initials: M
authors.lastname: Hiss
authors.forename: Isaac
authors.initials: I
authors.lastname: Engel
authors.forename: Konrad
authors.initials: K
authors.lastname: Peukert
authors.forename: Klaus
authors.initials: K
authors.lastname: Ley
authors.forename: Hermann
authors.initials: H
authors.lastname: Haller
authors.forename: Mitchell
authors.initials: M
authors.lastname: Kronenberg
authors.forename: Sibylle
authors.initials: S
authors.lastname: von Vietinghoff
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D002450:Cell Communication; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D005699:Galactosylceramides / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000276:immunology; D006801:Humans; D007111:Immunity, Cellular; D007165:Immunosuppression Therapy; D007958:Leukocyte Count; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008875:Middle Aged; D055611:Natural Killer T-Cells / Q000276:immunology*; D009504:Neutrophils / Q000276:immunology*; D010538:Peritonitis / Q000276:immunology; D011828:Radiation Chimera; D013045:Species Specificity; D013047:Specific Pathogen-Free Organisms; D014157:Transcription Factors / Q000378:metabolism; D055815:Young Adult
chemical_list: D016207:Cytokines; D005699:Galactosylceramides; D014157:Transcription Factors; C493154:alpha-galactosylceramide