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          Institute: MPI für molekulare Biomedizin     Collection: Yearbook 2013     Display Documents

ID: 648327.0, MPI für molekulare Biomedizin / Yearbook 2013
Leukocyte function antigen-1, kindlin-3, and calcium flux orchestrate neutrophil recruitment during inflammation
Authors:Dixit, N.; Kim, M. H.; Rossaint, J.; Yamayoshi, I.; Zarbock, A.; Simon, S. I.
Date of Publication (YYYY-MM-DD):2012-12-15
Title of Journal:J Immunol
Issue / Number:12
Start Page:5954
End Page:5964
Review Status:Internal review
Audience:Not Specified
Abstract / Description:Neutrophil arrest and migration on inflamed endothelium involves a conformational shift in CD11a/CD18 (leukocyte function antigen-1; LFA-1) to a high-affinity and clustered state that determines the strength and lifetime of bond formation with ICAM-1. Cytoskeletal adapter proteins Kindlin-3 and Talin-1 anchor clustered LFA-1 to the cytoskeleton and facilitate the transition from neutrophil rolling to arrest. We recently reported that tensile force acts on LFA-1 bonds inducing their colocalization with Orai1, the predominant membrane store operated Ca(2+) channel that cooperates with the endoplasmic reticulum to elicit cytosolic flux. Because Kindlin-3 was recently reported to initiate LFA-1 clustering in lymphocytes, we hypothesized that it cooperates with Orai1 and LFA-1 in signaling local Ca(2+) flux necessary for shear-resistant neutrophil arrest. Using microfluidic flow channels combined with total internal reflection fluorescence microscopy, we applied defined shear stress to low- or high-affinity LFA-1 and imaged the spatiotemporal regulation of bond formation with Kindlin-3 recruitment and Ca(2+) influx. Orai1 and Kindlin-3 genes were silenced in neutrophil-like HL-60 cells to assess their respective roles in this process. Kindlin-3 was enriched within focal clusters of high-affinity LFA-1, which promoted physical linkage with Orai1. This macromolecular complex functioned to amplify inside-out Ca(2+) signaling in response to IL-8 stimulation by catalyzing an increased density of Talin-1 and consolidating LFA-1 clusters within sites of contact with ICAM-1. In this manner, neutrophils use focal adhesions as mechanosensors that convert shear stress-mediated tensile force into local bursts of Ca(2+) influx that catalyze cytoskeletal engagement and an adhesion-strengthened migratory phenotype.
Free Keywords:Animals; Calcium Signaling/genetics/*immunology; Cell Adhesion/genetics/immunology; Cytoskeletal Proteins/deficiency/*physiology; Gene Knockout Techniques; HL-60 Cells; Humans; Hydrodynamics; Inflammation/genetics/immunology/pathology; Lymphocyte Function-Associated Antigen-1/*physiology; Membrane Proteins/deficiency/*physiology; Mice; Mice, Inbred ICR; Neoplasm Proteins/deficiency/*physiology; Neutrophil Infiltration/genetics/*immunology; Stress, Physiological/immunology
External Publication Status:published
Document Type:Article
Communicated by:keuker
Affiliations:MPI für molekulare Biomedizin
External Affiliations:%G eng
Identifiers:ISSN:1550-6606 (Electronic) 0022-1767 (Linking) %R 10.4... [ID No:1]
URL:http://www.ncbi.nlm.nih.gov/pubmed/23144497 [ID No:2]
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