title: Dendritic cells amplify T cell-mediated immune responses in the central nervous system.
abstract: Neuroinflammation often starts with the invasion of T lymphocytes into the CNS leading to recruitment of macrophages and amplification of inflammation. In this study, we show that dendritic cells (DCs) facilitate T-T cell help in the CNS and contribute to the amplification of local neuroinflammation. We adoptively transferred defined amounts of naive TCR-transgenic (TCR) recombination-activating gene-1-deficient T cells into another TCR-transgenic mouse strain expressing different Ag specificity. Following adoptive transfers, we coinjected DCs that presented one or multiple Ags into the brain and followed the activation of T cells with defined specificities simultaneously. Injection of DCs presenting both Ags simultaneously led to significantly higher infiltration of T cells into the brain compared with injection of a mixture of DCs pulsed with two Ags separately. DCs mediated either cooperative or competitive interactions between T cell populations with different specificities depending upon their MHC-restricting element usage. These results suggest that DC-mediated cooperation between brain-infiltrating T cells of different Ag specificities in the CNS plays an important role in regulation of neuroinflammation. This work also implies that blocking Ag-specific responses may block not only the targeted specificities, but may also effectively block their cooperative assistance to other T cells. Therefore, these data justify more attention to Ag-specific therapeutic approaches for neuroinflammation.
authors.affiliation: Cellular and Molecular Pathology Graduate Program, Department of Pathology, University of Wisconsin, 1300 University Avenue, Madison, WI 53706, USA.
authors.forename: Jozsef
authors.initials: J
authors.lastname: Karman
authors.forename: Hamlet H
authors.initials: HH
authors.lastname: Chu
authors.forename: Dominic O
authors.initials: DO
authors.lastname: Co
authors.forename: Christine M
authors.initials: CM
authors.lastname: Seroogy
authors.forename: Matyas
authors.initials: M
authors.lastname: Sandor
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Fabry
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D017951:Antigen Presentation / Q000276:immunology*; D001921:Brain / Q000276:immunology* / Q000473:pathology; D002450:Cell Communication / Q000276:immunology*; D003713:Dendritic Cells / Q000276:immunology*; D005434:Flow Cytometry; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D007150:Immunohistochemistry; D007249:Inflammation / Q000276:immunology / Q000473:pathology; D008213:Lymphocyte Activation / Q000276:immunology; D051379:Mice; D008822:Mice, Transgenic; D034741:RNA, Small Interfering; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000276:immunology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000949:Histocompatibility Antigens Class II; D034741:RNA, Small Interfering; D011948:Receptors, Antigen, T-Cell