title: Imaging of plasmacytoid dendritic cell interactions with T cells.
abstract: Plasmacytoid dendritic cells (pDCs) efficiently produce type I interferon and participate in adaptive immune responses, although the molecular interactions between pDCs and antigen-specific T cells remain unknown. This study examines immune synapse (IS) formation between murine pDCs and CD4(+) T cells. Mature pDCs formed canonical ISs, involving relocation to the contact site of the microtubule-organizing center, F-actin, protein kinase C-, and pVav, and activation of early signaling molecules in T cells. However, immature pDCs were less efficient at forming conjugates with T cells and inducing IS formation, microtubule-organizing center translocation, and T-cell signaling and activation. Time-lapse videomicroscopy and 2-photon in vivo imaging of pDC-T-cell interactions revealed that immature pDCs preferentially mediated transient interactions, whereas mature pDCs promoted more stable contacts. Our data indicate that, under steady-state conditions, pDCs preferentially establish transient contacts with naive T cells and show a very modest immunogenic capability, whereas on maturation, pDCs are able to form long-lived contacts with T cells and significantly enhance their capacity to activate these lymphocytes.
authors.affiliation: Departamento de Biología Vascular e Inflamación, Centro Nacional de Investigaciones Cardiovasculares, Melchor Fernández Almagro 3, Madrid, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Mittelbrunn
authors.forename: Gloria
authors.initials: G
authors.lastname: Martínez del Hoyo
authors.forename: María
authors.initials: M
authors.lastname: López-Bravo
authors.forename: Noa B
authors.initials: NB
authors.lastname: Martín-Cofreces
authors.forename: Alix
authors.initials: A
authors.lastname: Scholer
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Hugues
authors.forename: Luc
authors.initials: L
authors.lastname: Fetler
authors.forename: Sebastián
authors.initials: S
authors.lastname: Amigorena
authors.forename: Carlos
authors.initials: C
authors.lastname: Ardavín
authors.forename: Francisco
authors.initials: F
authors.lastname: Sánchez-Madrid
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D000938:Antigen-Presenting Cells / Q000166:cytology / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000276:immunology*; D002450:Cell Communication / Q000276:immunology*; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000166:cytology* / Q000276:immunology*; D054992:Immunological Synapses; D008198:Lymph Nodes / Q000166:cytology; D008213:Lymphocyte Activation / Q000276:immunology; D008565:Membrane Proteins / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D018715:Microscopy, Video; D022101:Microtubule-Organizing Center / Q000276:immunology; D010047:Ovalbumin / Q000494:pharmacology; D015398:Signal Transduction / Q000276:immunology; D013047:Specific Pathogen-Free Organisms
chemical_list: D008565:Membrane Proteins; C084881:flt3 ligand protein; D010047:Ovalbumin