title: A Cytokine-Independent Approach To Identify Antigen-Specific Human Germinal Center T Follicular Helper Cells and Rare Antigen-Specific CD4+ T Cells in Blood.
abstract: Detection of Ag-specific CD4(+) T cells is central to the study of many human infectious diseases, vaccines, and autoimmune diseases. However, such cells are generally rare and heterogeneous in their cytokine profiles. Identification of Ag-specific germinal center (GC) T follicular helper (Tfh) cells by cytokine production has been particularly problematic. The function of a GC Tfh cell is to selectively help adjacent GC B cells via cognate interaction; thus, GC Tfh cells may be stingy cytokine producers, fundamentally different from Th1 or Th17 cells in the quantities of cytokines produced. Conventional identification of Ag-specific cells by intracellular cytokine staining relies on the ability of the CD4(+) T cell to generate substantial amounts of cytokine. To address this problem, we have developed a cytokine-independent activation-induced marker (AIM) methodology to identify Ag-specific GC Tfh cells in human lymphoid tissue. Whereas Group A Streptococcus-specific GC Tfh cells produced minimal detectable cytokines by intracellular cytokine staining, the AIM method identified 85-fold more Ag-specific GC Tfh cells. Intriguingly, these GC Tfh cells consistently expressed programmed death ligand 1 upon activation. AIM also detected non-Tfh cells in lymphoid tissue. As such, we applied AIM for identification of rare Ag-specific CD4(+) T cells in human peripheral blood. Dengue, tuberculosis, and pertussis vaccine-specific CD4(+) T cells were readily detectable by AIM. In summary, cytokine assays missed 98% of Ag-specific human GC Tfh cells, reflecting the biology of these cells, which could instead be sensitively identified by coexpression of TCR-dependent activation markers.
authors.affiliation: La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037; Division of Infectious Diseases, University of California, San Diego, La Jolla, CA 92093;
authors.forename: Jennifer M
authors.identifier: 0000-0002-1672-0657
authors.initials: JM
authors.lastname: Dan
authors.affiliation: La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037;
authors.forename: Cecilia S
authors.initials: CS
authors.lastname: Lindestam Arlehamn
authors.affiliation: La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037;
authors.forename: Daniela
authors.identifier: 0000-0003-2968-7371
authors.initials: D
authors.lastname: Weiskopf
authors.affiliation: La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037;
authors.forename: Ricardo
authors.identifier: 0000-0001-9785-5272
authors.initials: R
authors.lastname: da Silva Antunes
authors.affiliation: La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037; Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037; and.
authors.forename: Colin
authors.initials: C
authors.lastname: Havenar-Daughton
authors.affiliation: La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037; Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037; and.
authors.forename: Samantha M
authors.identifier: 0000-0001-5273-0898
authors.initials: SM
authors.lastname: Reiss
authors.affiliation: Rady Children's Hospital, San Diego, CA 92025.
authors.forename: Matthew
authors.identifier: 0000-0002-7022-9578
authors.initials: M
authors.lastname: Brigger
authors.affiliation: Rady Children's Hospital, San Diego, CA 92025.
authors.forename: Marcella
authors.identifier: 0000-0001-9771-6221
authors.initials: M
authors.lastname: Bothwell
authors.affiliation: La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037;
authors.forename: Alessandro
authors.identifier: 0000-0001-7013-2250
authors.initials: A
authors.lastname: Sette
authors.affiliation: La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037; Division of Infectious Diseases, University of California, San Diego, La Jolla, CA 92093; Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037; and shane@lji.org.
authors.forename: Shane
authors.identifier: 0000-0002-6484-6262
authors.initials: S
authors.lastname: Crotty
mesh_terms: D015415:Biomarkers / Q000097:blood*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D016207:Cytokines / Q000032:analysis / Q000096:biosynthesis; D058501:Enzyme-Linked Immunospot Assay; D005434:Flow Cytometry; D018858:Germinal Center / Q000166:cytology / Q000276:immunology; D006801:Humans; D007158:Immunologic Techniques / Q000379:methods*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: D015415:Biomarkers; D016207:Cytokines