title: Characterization of lung infection-induced TCRγδ T cell phenotypes by CyTOF mass cytometry.
abstract: T cell receptor γδ cells are known to be the primary effector T cells involved in the response to bacterial infections, yet their phenotypic characteristics are not as well established as other T cell subsets. In this study, we used cytometry by time-of-flight mass cytometry to better characterize the phenotypic response of T cell receptor γδ cells to Streptococcus pneumoniae lung infection. Mice were infected, and cells from lung washouts, spleen, and lymph nodes were stained to detect cell-surface, intracellular, and signaling markers. We observed that infection caused a significant increase in T cell receptor γδ cells, which expressed high interferon-γ and interleukin-17A levels. Profiling T cell receptor γδ cells by cytometry by time-of-flight revealed that activated γδ T cells uniquely coexpressed cell-surface Gr-1, cluster of differentiation 14, and cluster of differentiation 274 (programmed death-ligand 1). Further classification of Gr-1 expression patterns on T cell receptor γδ cells demonstrated that Gr-1(+) T cell receptor γδ cells were the primary source of interferon-γ, whereas Gr-1(-) cells mostly expressed interleukin-17A. Gr-1(+) T cell receptor γδ cells also showed higher ζ-chain-associated protein kinase 70, p38, and 4eBP1 signaling in response to infection as compared with Gr-1(-) T cell receptor γδ cells. Taken together, Gr-1 expression patterns on γδ T cells in the lung provide a robust marker to differentiate interferon-γ- and interleukin-17A-producing subsets involved in the early immune response to bacterial pneumonia.
authors.affiliation: *Department of Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA; and Department of Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: Lorenz
authors.initials: L
authors.lastname: Wanke-Jellinek
authors.affiliation: *Department of Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA; and Department of Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: Joshua W
authors.initials: JW
authors.lastname: Keegan
authors.affiliation: *Department of Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA; and Department of Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: James W
authors.initials: JW
authors.lastname: Dolan
authors.affiliation: *Department of Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA; and Department of Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany jlederer@rics.bwh.harvard.edu.
authors.forename: James A
authors.initials: JA
authors.lastname: Lederer
mesh_terms: D000818:Animals; D005434:Flow Cytometry; D007371:Interferon-gamma / Q000096:biosynthesis; D020381:Interleukin-17 / Q000096:biosynthesis; D008297:Male; D051379:Mice; D010641:Phenotype; D011018:Pneumonia, Pneumococcal / Q000276:immunology*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis*; D019707:Receptors, Chemokine / Q000032:analysis; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: C503133:Gr-1 protein, mouse; D020381:Interleukin-17; D016692:Receptors, Antigen, T-Cell, gamma-delta; D019707:Receptors, Chemokine; D007371:Interferon-gamma
keywords: IFN-γ; IL-17; immune response; pneumonia