title: Dynamic imaging of the effector immune response to listeria infection in vivo.
abstract: Host defense against the intracellular pathogen Listeria monocytogenes (Lm) requires innate and adaptive immunity. Here, we directly imaged immune cell dynamics at Lm foci established by dendritic cells in the subcapsular red pulp (scDC) using intravital microscopy. Blood borne Lm rapidly associated with scDC. Myelomonocytic cells (MMC) swarmed around non-motile scDC forming foci from which blood flow was excluded. The depletion of scDC after foci were established resulted in a 10-fold reduction in viable Lm, while graded depletion of MMC resulted in 30-1000 fold increase in viable Lm in foci with enhanced blood flow. Effector CD8+ T cells at sites of infection displayed a two-tiered reduction in motility with antigen independent and antigen dependent components, including stable interactions with infected and non-infected scDC. Thus, swarming MMC contribute to control of Lm prior to development of T cell immunity by direct killing and sequestration from blood flow, while scDC appear to promote Lm survival while preferentially interacting with CD8+ T cells in effector sites.
authors: Program in Molecular Pathogenesis, Helen L. and Martin S. Kimmel Center for Biology and Medicine of the Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York City, New York, United States of America.
authors: Janelle C
authors: JC
authors: Waite
authors: Ingrid
authors: I
authors: Leiner
authors: Peter
authors: P
authors: Lauer
authors: Chris S
authors: CS
authors: Rae
authors: Gaetan
authors: G
authors: Barbet
authors: Huan
authors: H
authors: Zheng
authors: Daniel A
authors: DA
authors: Portnoy
authors: Eric G
authors: EG
authors: Pamer
authors: Michael L
authors: ML
authors: Dustin
mesh_terms: D056704:Adaptive Immunity; D000818:Animals; D003602:Cytotoxicity, Immunologic; D003713:Dendritic Cells / Q000276:immunology / Q000473:pathology; D005260:Female; D055879:Gene Knock-In Techniques; D054884:Host-Pathogen Interactions; D007113:Immunity, Innate; D008089:Listeria monocytogenes / Q000472:pathogenicity*; D008088:Listeriosis / Q000276:immunology / Q000473:pathology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D009000:Monocytes / Q000276:immunology / Q000473:pathology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology / Q000473:pathology*