Faculty Collaboration Database

CD14-dependent activation of human endothelial cells by Bacteroides fragilis outer membrane. J Surg Res 1998 Feb 01;74(2):103-11

Date

05/20/1998

Pubmed ID

9587347

DOI

10.1006/jsre.1997.5248

Scopus ID

2-s2.0-0032004583 (requires institutional sign-in at Scopus site)   7 Citations

Abstract

We studied the capacity of isolated Bacteriodes fragilis outer membrane, B. fragilis NCTC9343 lipopolysaccharide (LPS; endotoxin), and B. fragilis NCTC9343 capsular polysaccharides to activate human umbilical vein endothelial cell (HUVEC) monolayers. To assess HUVEC activation, E-selectin expression was measured by enzyme-linked immunosorbent assay (ELISA), Northern blot analysis for E-selectin-specific mRNA, and electrophoretic gel mobility shift assay (EMSA) for NF-kappa B, a transcription factor necessary for E-selectin gene activation. Exposure of HUVECs to B. fragilis outer membrane fractions, separated from other components of the B. fragilis cell wall by isopycnic, sucrose gradient centrifugation, significantly increased surface expression of E-selectin and induced functional endothelial cell-dependent leukocyte adhesion. B. fragilis outer membranes induced translocation of NF-kappa B to HUVEC nuclei and accumulation of E-selectin mRNA in HUVEC cytoplasm. E-selectin expression induced by B. fragilis outer membranes was not blocked by polymixin B. In contrast, E-selectin expression induced by outer membrane fractions purified from E. coli was competitively inhibited by polymixin B. Neither purified B. fragilis LPS, a prominent constituent of the outer membrane, nor purified B. fragilis capsular polysaccharides induced HUVEC activation. Two different monoclonal antibodies directed against human CD14 completely inhibited B. fragilis outer membrane-induced NF-kappa B activation, E-selectin transcription, and E-selectin surface expression. We conclude that the outer membrane component of the B. fragilis cell wall contains a proinflammatory factor(s), that is not LPS, which induces human endothelial cell activation by a soluble CD14-dependent mechanism.

Author List

Sato TT, Kovacich JC, Boyle EM Jr, Haddix TL, Weintraub A, Pohlman TH

MESH terms used to index this publication - Major topics in bold

Antibodies, Monoclonal
Bacterial Outer Membrane Proteins
Bacteroides fragilis
Blotting, Northern
Cell Adhesion
Cells, Cultured
E-Selectin
Electrophoresis, Polyacrylamide Gel
Endothelium, Vascular
Enzyme-Linked Immunosorbent Assay
Gene Expression Regulation
Humans
Lipopolysaccharide Receptors
Lipopolysaccharides
NF-kappa B
Neutrophils
Polymyxin B
RNA, Messenger
Transcriptional Activation