title: Induction of a Th1 response from Th2-polarized T cells by activated dendritic cells: dependence on TCR:peptide-MHC interaction, ICAM-1, IL-12, and IFN-gamma.
abstract: Dendritic cells (DC) are important regulators of T cell immunity. The degree of stimulation, the pattern of costimulatory molecules expressed, and the cytokines secreted by DC dictate the nature of the effector and memory cells generated, particularly with respect to their Th1 or Th2 phenotypes. In this study, we demonstrate that the addition of activated DC to spleen cultures containing established Th2-polarized CD4(+) T cells was sufficient to suppress Th2 and induce Th1 cytokines in a recall response, a phenomenon referred to as phenotype reversal. The ability of activated DC to induce phenotype reversal displayed exquisite Ag specificity. The DC activator B7-DC cross-linking Ab (XAb) was >10,000-fold more efficient at inducing phenotype reversal than the TLR agonists CpG-oligodeoxynucleotide and Gardiquimod. Characterization of the mechanisms governing phenotype reversal revealed the requirement for cognate interaction between the TCR:peptide-MHC complex, the expression of the costimulation/adhesion molecule ICAM-1, and secretion of IL-12 and IFN-gamma by the activated DC. The requirement for the costimulation/adhesion molecule SLAM (signaling lymphocytic activation molecule) was found to be quantitative. Thus, activation of DC, particularly by crosslinking B7-DC, can modulate well-established Th2 T cell responses in an Ag-specific manner. Because the regulation of mouse and human DC by B7-DC XAb overlaps in several significant ways, immune modulation with B7-DC XAb is a potential strategy for treating Th2-mediated diseases.
authors.affiliation: Department of Immunology, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: Suresh
authors.initials: S
authors.lastname: Radhakrishnan
authors.forename: Karla R
authors.initials: KR
authors.lastname: Wiehagen
authors.forename: Vesna
authors.initials: V
authors.lastname: Pulko
authors.forename: Virginia
authors.initials: V
authors.lastname: Van Keulen
authors.forename: William A
authors.initials: WA
authors.lastname: Faubion
authors.forename: Keith L
authors.initials: KL
authors.lastname: Knutson
authors.forename: Larry R
authors.initials: LR
authors.lastname: Pease
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D017951:Antigen Presentation / Q000187:drug effects / Q000276:immunology; D015703:Antigens, CD / Q000276:immunology; D018122:B7-1 Antigen / Q000276:immunology; D002478:Cells, Cultured; D018899:CpG Islands / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology*; D006649:Histocompatibility Antigens / Q000276:immunology*; D007154:Immune System Diseases / Q000276:immunology; D007152:Immunologic Capping / Q000187:drug effects / Q000276:immunology; D018799:Intercellular Adhesion Molecule-1 / Q000276:immunology*; D007371:Interferon-gamma / Q000276:immunology*; D018664:Interleukin-12 / Q000276:immunology*; D051379:Mice; D018345:Mice, Knockout; D010455:Peptides / Q000276:immunology* / Q000494:pharmacology; D011485:Protein Binding / Q000276:immunology; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D011956:Receptors, Cell Surface / Q000276:immunology; D000071177:Signaling Lymphocytic Activation Molecule Family Member 1; D018417:Th1 Cells / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology*; D051193:Toll-Like Receptors / Q000819:agonists / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D018122:B7-1 Antigen; D006649:Histocompatibility Antigens; D010455:Peptides; D011948:Receptors, Antigen, T-Cell; D011956:Receptors, Cell Surface; D051193:Toll-Like Receptors; D018799:Intercellular Adhesion Molecule-1; D000071177:Signaling Lymphocytic Activation Molecule Family Member 1; D018664:Interleukin-12; D007371:Interferon-gamma