title: Autologous apoptotic T cells interact with dendritic cells, but do not affect their surface phenotype or their ability to induce recall immune responses.
abstract: Dendritic cells (DCs) play an important role in determining immunogenicity and the subsequent immune response. They may also have a role in maintaining peripheral tolerance to self-antigens by initiating an immune response only in the context of danger signals released from cells during stress, damage or death. These signals may originate from surrounding T cells as well as from other cells. Therefore, in this study the effect of autologous T cell injury on DC morphology and function has been investigated. Co-incubation of apoptotic or necrotic T cells with immature DCs altered their morphology towards a more mature appearance, with more cells showing activation as judged by spreading and formation of arborizing long processes. The apoptotic autologous T cells were rarely phagocytosed by immature DCs, compared to macrophages. The DC surface phenotype was not affected by the co-incubation with autologous injured T cells. The ability of DCs to elicit a secondary immune response was not altered by exposure to autologous injured T cells. These findings suggest that DC can continue to function in T cell activation, rather than in tolerogenic mode, even in the presence of large numbers of dying autologous T cells, such as may be present in the aftermath of an acute antiviral response.
authors.affiliation: Department of Sexually Transmitted Diseases, Windeyer Institute for Medical Sciences, Royal Free and University College Medical School, London, UK.
authors.forename: P J
authors.initials: PJ
authors.lastname: Newton
authors.forename: I V D
authors.initials: IV
authors.lastname: Weller
authors.forename: D R
authors.initials: DR
authors.lastname: Katz
authors.forename: B M
authors.initials: BM
authors.lastname: Chain
mesh_terms: D017951:Antigen Presentation; D017209:Apoptosis; D016923:Cell Death; D018920:Coculture Techniques; D003713:Dendritic Cells / Q000276:immunology*; D006801:Humans; D016130:Immunophenotyping; D008264:Macrophages / Q000276:immunology; D018613:Microscopy, Confocal; D008858:Microscopy, Phase-Contrast; D009336:Necrosis; D010587:Phagocytosis; D013601:T-Lymphocytes / Q000473:pathology*