|
|
||||||||



,1
* Neonatology Division and
Center for Experimental Therapeutics and Reperfusion Injury, Brigham and Womens Hospital, Harvard Medical School, Boston, Massachusetts, USA
1Correspondence: Brigham and Womens Hospital and Harvard Medical School, Thorn Building 704, 20 Shattuck St., Boston, MA 02115, USA. E-mail: colgan{at}zeus.bwh.harvard.edu
Sites of inflammation are associated with dramatic shifts in tissue metabolism. Inflammation can result in significant tissue hypoxia, with resultant induction of hypoxia-responsive genes. Given this association, we hypothesized that neutrophil (PMN) ligands expressed on epithelial cells may be regulated by hypoxia. Initial studies confirmed earlier results that epithelial hypoxia enhances PMN transepithelial migration and promotes apical clearance of PMN from the epithelial surface. A screen of known PMN ligands revealed a surprisingly stable expression pattern in hypoxia. However, this screen identified one gene, CD55, as a highly hypoxia-inducible molecule expressed on the apical membrane of mucosal epithelia. Subsequent studies verified the induction of CD55 mRNA and protein expression by hypoxia. Overexpression of CD55 by transfection in nonhypoxic epithelia resulted in a similar pattern of apical PMN clearance, and peptide mimetics corresponding to the PMN binding site on DAF blocked such apical clearance of PMN. Studies directed at understanding molecular pathways of hypoxia inducibility revealed that a
200 bp region of the CD55 gene conferred hypoxia inducibility for CD55. These studies identified a functional binding site for the transcriptional regulator hypoxia-inducible factor (HIF). Taken together, these results identify HIF-dependent induction of epithelial CD55 in the resolution of ongoing inflammation through clearance of apical PMN.Louis, N. A., Hamilton, K. E., Kong, T., Colgan, S. P. HIF-dependent induction of apical CD55 coordinates epithelial clearance of neutrophils.
Key Words: inflammation adhesion mucosa leukocyte resolution
This article has been cited by other articles:
![]() |
E. Krautkramer and M. Zeier Hantavirus Causing Hemorrhagic Fever with Renal Syndrome Enters from the Apical Surface and Requires Decay-Accelerating Factor (DAF/CD55) J. Virol., May 1, 2008; 82(9): 4257 - 4264. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. L. Campbell, N. A. Louis, S. E. Tomassetti, G. O. Canny, M. Arita, C. N. Serhan, and S. P. Colgan Resolvin E1 promotes mucosal surface clearance of neutrophils: a new paradigm for inflammatory resolution FASEB J, October 1, 2007; 21(12): 3162 - 3170. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Shaykhiev and R. Bals Interactions between epithelial cells and leukocytes in immunity and tissue homeostasis J. Leukoc. Biol., July 1, 2007; 82(1): 1 - 15. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. M. Cauvi, G. Cauvi, and K. M. Pollard Constitutive Expression of Murine Decay-Accelerating Factor 1 Is Controlled by the Transcription Factor Sp1 J. Immunol., September 15, 2006; 177(6): 3837 - 3847. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. C. Bosco, M. Puppo, C. Santangelo, L. Anfosso, U. Pfeffer, P. Fardin, F. Battaglia, and L. Varesio Hypoxia Modifies the Transcriptome of Primary Human Monocytes: Modulation of Novel Immune-Related Genes and Identification Of CC-Chemokine Ligand 20 as a New Hypoxia-Inducible Gene J. Immunol., August 1, 2006; 177(3): 1941 - 1955. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |