title: T Cell Responses against Mycobacterial Lipids and Proteins Are Poorly Correlated in South African Adolescents.
abstract: Human T cells are activated by both peptide and nonpeptide Ags produced by Mycobacterium tuberculosis. T cells recognize cell wall lipids bound to CD1 molecules, but effector functions of CD1-reactive T cells have not been systematically assessed in M. tuberculosis-infected humans. It is also not known how these features correlate with T cell responses to secreted protein Ags. We developed a flow cytometric assay to profile CD1-restricted T cells ex vivo and assessed T cell responses to five cell wall lipid Ags in a cross-sectional study of 19 M. tuberculosis-infected and 22 M. tuberculosis-uninfected South African adolescents. We analyzed six T cell functions using a recently developed computational approach for flow cytometry data in high dimensions. We compared these data with T cell responses to five protein Ags in the same cohort. We show that CD1b-restricted T cells producing antimycobacterial cytokines IFN-γ and TNF-α are detectable ex vivo in CD4(+), CD8(+), and CD4(-)CD8(-) T cell subsets. Glucose monomycolate was immunodominant among lipid Ags tested, and polyfunctional CD4 T cells specific for this lipid simultaneously expressed CD40L, IFN-γ, IL-2, and TNF-α. Lipid-reactive CD4(+) T cells were detectable at frequencies of 0.001-0.01%, and this did not differ by M. tuberculosis infection status. Finally, CD4 T cell responses to lipids were poorly correlated with CD4 T cell responses to proteins (Spearman rank correlation -0.01; p = 0.95). These results highlight the functional diversity of CD1-restricted T cells circulating in peripheral blood as well as the complementary nature of T cell responses to mycobacterial lipids and proteins. Our approach enables further population-based studies of lipid-specific T cell responses during natural infection and vaccination.
authors.affiliation: Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, WA 98109; seshadri@u.washington.edu.
authors.forename: Chetan
authors.initials: C
authors.lastname: Seshadri
authors.affiliation: Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109;
authors.forename: Lin
authors.initials: L
authors.lastname: Lin
authors.affiliation: South African TB Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7700, South Africa; Department of Pediatrics and Child Health, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7700, South Africa;
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Scriba
authors.affiliation: Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, WA 98109;
authors.forename: Glenna
authors.initials: G
authors.lastname: Peterson
authors.affiliation: Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109; HIV Vaccine Trials Network, Fred Hutchinson Cancer Research Center, Seattle, WA 98109;
authors.forename: David
authors.initials: D
authors.lastname: Freidrich
authors.affiliation: Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109; HIV Vaccine Trials Network, Fred Hutchinson Cancer Research Center, Seattle, WA 98109;
authors.forename: Nicole
authors.initials: N
authors.lastname: Frahm
authors.affiliation: Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109; HIV Vaccine Trials Network, Fred Hutchinson Cancer Research Center, Seattle, WA 98109; Department of Laboratory Medicine, University of Washington, Seattle WA 98109;
authors.forename: Stephen C
authors.initials: SC
authors.lastname: DeRosa
authors.affiliation: Division of Rheumatology, Allergy, and Immunology, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115;
authors.forename: D Branch
authors.initials: DB
authors.lastname: Moody
authors.affiliation: Institut de Pharmacologie et Biologie Structurale, Centre National de la Recherche Scientifique, Toulouse 31077, France; and.
authors.forename: Jacques
authors.initials: J
authors.lastname: Prandi
authors.affiliation: Institut de Pharmacologie et Biologie Structurale, Centre National de la Recherche Scientifique, Toulouse 31077, France; and.
authors.forename: Martine
authors.initials: M
authors.lastname: Gilleron
authors.affiliation: Division of Community Health, Stellenbosch University, Stellanbosch 7602, South Africa.
authors.forename: Hassan
authors.initials: H
authors.lastname: Mahomed
authors.affiliation: Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109;
authors.forename: Wenxin
authors.initials: W
authors.lastname: Jiang
authors.affiliation: Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109;
authors.forename: Greg
authors.initials: G
authors.lastname: Finak
authors.affiliation: South African TB Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7700, South Africa; Department of Pediatrics and Child Health, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7700, South Africa;
authors.forename: Willem A
authors.initials: WA
authors.lastname: Hanekom
authors.affiliation: Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109;
authors.forename: Raphael
authors.initials: R
authors.lastname: Gottardo
authors.affiliation: Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109; HIV Vaccine Trials Network, Fred Hutchinson Cancer Research Center, Seattle, WA 98109;
authors.forename: M Juliana
authors.initials: MJ
authors.lastname: McElrath
authors.affiliation: Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, WA 98109;
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Hawn
mesh_terms: D000293:Adolescent; D000942:Antigens, Bacterial / Q000276:immunology; D018949:Antigens, CD1 / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D023201:CD40 Ligand / Q000096:biosynthesis; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002473:Cell Wall / Q000276:immunology; D003430:Cross-Sectional Studies; D005260:Female; D005434:Flow Cytometry; D006017:Glycolipids / Q000276:immunology; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D007376:Interleukin-2 / Q000096:biosynthesis; D020014:K562 Cells; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D008563:Membrane Lipids / Q000276:immunology*; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D013019:South Africa / Q000453:epidemiology; D014397:Tuberculosis, Pulmonary / Q000453:epidemiology / Q000276:immunology* / Q000382:microbiology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D000942:Antigens, Bacterial; D018949:Antigens, CD1; D006017:Glycolipids; C508594:IL2 protein, human; D007376:Interleukin-2; D008563:Membrane Lipids; D014409:Tumor Necrosis Factor-alpha; C048938:glucose mycolate; D023201:CD40 Ligand; D007371:Interferon-gamma