Differential requirement for ROCK in dendritic cell migration within lymphatic capillaries in steady-state and inflammation

Blood. 2012 Sep 13;120(11):2249-58. doi: 10.1182/blood-2012-03-417923. Epub 2012 Jul 31.

Abstract

Dendritic cell (DC) migration via lymphatic vessels to draining lymph nodes (dLNs) is crucial for the initiation of adaptive immunity. We imaged this process by intravital microscopy (IVM) in the ear skin of transgenic mice bearing red-fluorescent vasculature and yellow-fluorescent DCs. DCs within lymphatic capillaries were rarely transported by flow, but actively migrated within lymphatics and were significantly faster than in the interstitium. Pharmacologic blockade of the Rho-associated protein kinase (ROCK), which mediates nuclear contraction and de-adhesion from integrin ligands, significantly reduced DC migration from skin to dLNs in steady-state. IVM revealed that ROCK blockade strongly reduced the velocity of interstitial DC migration, but only marginally affected intralymphatic DC migration. By contrast, during tissue inflammation, ROCK blockade profoundly decreased both interstitial and intralymphatic DC migration. Inhibition of intralymphatic migration was paralleled by a strong up-regulation of ICAM-1 in lymphatic endothelium, suggesting that during inflammation ROCK mediates de-adhesion of DC-expressed integrins from lymphatic-expressed ICAM-1. Flow chamber assays confirmed an involvement of lymphatic-expressed ICAM-1 and DC-expressed ROCK in DC crawling on lymphatic endothelium. Overall, our findings further define the role of ROCK in DC migration to dLNs and reveal a differential requirement for ROCK in intralymphatic DC crawling during steady-state and inflammation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Adhesion Molecules / genetics
  • Cell Adhesion Molecules / metabolism
  • Cell Movement* / drug effects
  • Crosses, Genetic
  • Dendritic Cells / drug effects
  • Dendritic Cells / immunology
  • Dendritic Cells / metabolism*
  • Dendritic Cells / pathology
  • Dermatitis, Contact / drug therapy
  • Dermatitis, Contact / immunology
  • Dermatitis, Contact / metabolism*
  • Dermatitis, Contact / pathology
  • Endothelium, Lymphatic / drug effects
  • Endothelium, Lymphatic / immunology*
  • Endothelium, Lymphatic / metabolism
  • Endothelium, Lymphatic / pathology
  • Intercellular Adhesion Molecule-1 / metabolism
  • Luminescent Proteins / genetics
  • Luminescent Proteins / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Microscopy, Fluorescence
  • Microscopy, Video
  • Protein Kinase Inhibitors / pharmacology
  • Radiation Chimera
  • Recombinant Fusion Proteins / metabolism
  • Skin / drug effects
  • Skin / immunology
  • Skin / metabolism
  • Skin / pathology
  • Up-Regulation / drug effects
  • rho-Associated Kinases / antagonists & inhibitors
  • rho-Associated Kinases / genetics
  • rho-Associated Kinases / metabolism*

Substances

  • Cell Adhesion Molecules
  • Icam1 protein, mouse
  • Luminescent Proteins
  • Protein Kinase Inhibitors
  • Recombinant Fusion Proteins
  • Intercellular Adhesion Molecule-1
  • rho-Associated Kinases