title: NKT cells play a limited role in the neutrophilic inflammatory responses and host defense to pulmonary infection with Pseudomonas aeruginosa.
abstract: CD1d-restricted NKT cells are reported to play a critical role in the host defense to pulmonary infection with Pseudomonas aeruginosa. However, the contribution of a major subset expressing a Valpha14-Jalpha18 gene segment remains unclear. In the present study, we re-evaluated the role of NKT cells in the neutrophilic inflammatory responses and host defense to this infection using mice genetically lacking Jalpha18 or CD1d (Jalpha18KO or CD1dKO mice). These mice cleared the bacteria in lungs at a comparable level to wild-type (WT) mice. There was no significant difference in the local neutrophilic responses, as shown by neutrophil counts and synthesis of MIP-2 and TNF-alpha, in either KO mice from those in WT mice. Administration of alpha-galactosylceramide, a specific activator of Valpha14+ NKT cells, failed to promote the bacterial clearance and neutrophilic responses, although the same treatment increased the synthesis of IFN-gamma, suggesting the involvement of this cytokine downstream of NKT cells. In agreement against this notion, these responses were not further enhanced by administration of recombinant IFN-gamma in the infected Jalpha18KO mice. Our data indicate that NKT cells play a limited role in the development of neutrophilic inflammatory responses and host defense to pulmonary infection with P. aeruginosa.
authors.affiliation: Department of Medicine and Therapeutics, Control and Prevention of Infectious Diseases, Faculty of Medicine, University of the Ryukyus, Okinawa, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kinjo
authors.forename: Masashi
authors.initials: M
authors.lastname: Nakamatsu
authors.forename: Chikara
authors.initials: C
authors.lastname: Nakasone
authors.forename: Natsuo
authors.initials: N
authors.lastname: Yamamoto
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kinjo
authors.forename: Kazuya
authors.initials: K
authors.lastname: Miyagi
authors.forename: Kaori
authors.initials: K
authors.lastname: Uezu
authors.forename: Kiwamu
authors.initials: K
authors.lastname: Nakamura
authors.forename: Futoshi
authors.initials: F
authors.lastname: Higa
authors.forename: Masao
authors.initials: M
authors.lastname: Tateyama
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Takeda
authors.forename: Toshinori
authors.initials: T
authors.lastname: Nakayama
authors.forename: Masaru
authors.initials: M
authors.lastname: Taniguchi
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Kaku
authors.forename: Jiro
authors.initials: J
authors.lastname: Fujita
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Kawakami
mesh_terms: D000818:Animals; D002452:Cell Count; D054426:Chemokine CXCL2; D018925:Chemokines / Q000032:analysis; D005699:Galactosylceramides / Q000008:administration & dosage / Q000494:pharmacology; D007155:Immunologic Factors / Q000008:administration & dosage / Q000494:pharmacology; D007249:Inflammation / Q000276:immunology; D007371:Interferon-gamma / Q000096:biosynthesis / Q000276:immunology; D007694:Killer Cells, Natural / Q000276:immunology*; D008168:Lung / Q000382:microbiology; D016131:Lymphocyte Subsets / Q000276:immunology; D051379:Mice; D018345:Mice, Knockout; D009504:Neutrophils / Q000276:immunology*; D018410:Pneumonia, Bacterial / Q000276:immunology* / Q000382:microbiology; D011552:Pseudomonas Infections / Q000276:immunology* / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
chemical_list: D054426:Chemokine CXCL2; D018925:Chemokines; C404915:Cxcl2 protein, mouse; D005699:Galactosylceramides; D007155:Immunologic Factors; D014409:Tumor Necrosis Factor-alpha; C493154:alpha-galactosylceramide; D007371:Interferon-gamma