Accuri C6 Flow Cytometer System
Originally published online as doi:10.1189/jlb.0209062 on August 25, 2009

Published online before print August 25, 2009
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplemental Figures & Tables
Right arrow Buy
Right arrow All Versions of this Article:
jlb.0209062v1
86/6/1331    most recent
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Google Scholar
Right arrow Articles by Williams, M. R.
Right arrow Articles by McIntire, L. V.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Williams, M. R.
Right arrow Articles by McIntire, L. V.
(Journal of Leukocyte Biology. 2009;86:1331-1343.)
© 2009 Society for Leukocyte Biology

Transmigration across activated endothelium induces transcriptional changes, inhibits apoptosis, and decreases antimicrobial protein expression in human monocytes

Marcie R. Williams*, Yumiko Sakurai*, Susu M. Zughaier{dagger}, Suzanne G. Eskin* and Larry V. McIntire*,1

* The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, and
{dagger} Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA

1. Correspondence: The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, 313 Ferst Dr., Atlanta, GA 30332-0535, USA. E-mail: larry.mcintire{at}bme.gatech.edu

ABSTRACT

We investigated the hypothesis that transmigration drives monocyte transcriptional changes. Using Agilent whole human genome microarrays, we identified over 692 differentially expressed genes (2x, P<0.05) in freshly isolated human monocytes following 1.5 h of transmigration across IL-1β-stimulated ECs compared with untreated monocytes. Genes up-regulated by monocyte transmigration belong to a number of over-represented functional groups including immune response and inhibition of apoptosis. qRT-PCR confirmed increased expression of MCP-1 and -3 and of NAIP following monocyte transmigration. Additionally, quantification of Annexin V binding revealed a reduction in apoptosis following monocyte transmigration. Comparison of gene expression in transmigrated monocytes with additional controls (monocytes that failed to transmigrate and monocytes incubated beneath stimulated ECs) revealed 89 differentially expressed genes, which were controlled by the process of diapedesis. Functional annotation of these genes showed down-regulation of antimicrobial genes (e.g., {alpha}-defensin down 50x, cathelicidin down 9x, and CTSG down 3x). qRT-PCR confirmed down-regulation of these genes. Immunoblots confirmed that monocyte diapedesis down-regulates {alpha}-defensin protein expression. However, transmigrated monocytes were functional and retained intact cytokine and chemokine release upon TLR ligand exposure. Overall, these data indicate that the process of monocyte transmigration across stimulated ECs promotes further monocyte recruitment and inhibits monocyte apoptosis. Unexpectedly, following transmigration, monocytes displayed reduced antimicrobial protein expression.

Key Words: IL-1β • endothelial cells • cationic antimicrobial peptide (CAMP) below.