title: GM-CSF production allows the identification of immunoprevalent antigens recognized by human CD4+ T cells following smallpox vaccination.
abstract: The threat of bioterrorism with smallpox and the broad use of vaccinia vectors for other vaccines have led to the resurgence in the study of vaccinia immunological memory. The importance of the role of CD4+ T cells in the control of vaccinia infection is well known. However, more CD8+ than CD4+ T cell epitopes recognized by human subjects immunized with vaccinia virus have been reported. This could be, in part, due to the fact that most of the studies that have identified human CD4+ specific protein-derived fragments or peptides have used IFN-γ production to evaluate vaccinia specific T cell responses. Based on these findings, we reasoned that analyzing a large panel of cytokines would permit us to generate a more complete analysis of the CD4 T cell responses. The results presented provide clear evidence that TNF-α is an excellent readout of vaccinia specificity and that other cytokines such as GM-CSF can be used to evaluate the reactivity of CD4+ T cells in response to vaccinia antigens. Furthermore, using these cytokines as readout of vaccinia specificity, we present the identification of novel peptides from immunoprevalent vaccinia proteins recognized by CD4+ T cells derived from smallpox vaccinated human subjects. In conclusion, we describe a "T cell-driven" methodology that can be implemented to determine the specificity of the T cell response upon vaccination or infection. Together, the single pathogen in vitro stimulation, the selection of CD4+ T cells specific to the pathogen by limiting dilution, the evaluation of pathogen specificity by detecting multiple cytokines, and the screening of the clones with synthetic combinatorial libraries, constitutes a novel and valuable approach for the elucidation of human CD4+ T cell specificity in response to large pathogens.
authors.affiliation: Torrey Pines Institute for Molecular Studies, San Diego, California, United States of America.
authors.forename: Valeria
authors.initials: V
authors.lastname: Judkowski
authors.forename: Alcinette
authors.initials: A
authors.lastname: Bunying
authors.forename: Feng
authors.initials: F
authors.lastname: Ge
authors.forename: Jon R
authors.initials: JR
authors.lastname: Appel
authors.forename: Kingyee
authors.initials: K
authors.lastname: Law
authors.forename: Atima
authors.initials: A
authors.lastname: Sharma
authors.forename: Claudia
authors.initials: C
authors.lastname: Raja-Gabaglia
authors.forename: Patricia
authors.initials: P
authors.lastname: Norori
authors.forename: Radleigh G
authors.initials: RG
authors.lastname: Santos
authors.forename: Marc A
authors.initials: MA
authors.lastname: Giulianotti
authors.forename: Mark K
authors.initials: MK
authors.lastname: Slifka
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Douek
authors.forename: Barney S
authors.initials: BS
authors.lastname: Graham
authors.forename: Clemencia
authors.initials: C
authors.lastname: Pinilla
mesh_terms: D000595:Amino Acid Sequence; D000938:Antigen-Presenting Cells / Q000276:immunology / Q000378:metabolism; D000941:Antigens / Q000276:immunology*; D000956:Antigens, Viral / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D002460:Cell Line; D002478:Cells, Cultured; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000276:immunology* / Q000378:metabolism; D006684:HLA-DR Antigens / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007371:Interferon-gamma / Q000276:immunology / Q000378:metabolism; D012899:Smallpox / Q000276:immunology; D012900:Smallpox Vaccine / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology / Q000378:metabolism; D014611:Vaccination; D014615:Vaccinia / Q000276:immunology; D014616:Vaccinia virus / Q000276:immunology
chemical_list: D000941:Antigens; D000956:Antigens, Viral; D006684:HLA-DR Antigens; D012900:Smallpox Vaccine; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; D016178:Granulocyte-Macrophage Colony-Stimulating Factor