J Bacteriol Virol.  2002 Jun;32(2):147-157.

Expression of Cyclooxygenase-2 in Human Intestinal Epithelial Cells Stimulated with Bacteroides fragilis Enterotoxin

• Kim JM
• Kang SJ
• Cho SJ
• Jung HY
• Oh YK
• Kim YJ

Abstract

A ~20 kDa heat-labile toxin (BFT) produced by enterotoxigenic B. fragilis induces chemokine responses that may be associated with mucosal inflammation. To determine whether epithelial cells can contribute to BFT-induced inflammation, we assessed the expression of cyclooxygenase (COX)-2 in BFT-stimulated human intestinal epithelial cells. Human intestinal epithelial cell lines, HT-29 and Caco-2, were incubated with purified BFT. COX-2 mRNA and protein expression were measured by quantitative RT-PCR and Western blot analysis, respectively. BFT increased expression of COX-2, not that of COX-1, in human intestinal epithelial cell lines. Up-regulated COX-2 expression was paralleled by increased prostaglandin E2 (PGE2) production measured by the radioimmunoassay. PGE2 was predominantly secreted from the basolateral surface of BFT-treated epithelial cells, whereas lactate dehydrogenase was released predominantly from the apical surface. Moreover, the COX-2 expression and PGE2 production were significantly suppressed when NF-kappaB activity was inhibited. The basolateral secretion of PGE2 by up-regulated COX-2 in the BFT-stimulated colon epithelial cells seems to contribute to the inflammatory response in the underlying intestinal mucosa.

Keyword

Bacteroides fragilis enterotoxin; Cyclooxygenase-2; NF-kappaB; Prostaglandin

MeSH Terms

Bacteroides fragilis*
Bacteroides*
Blotting, Western
Colon
Cyclooxygenase 2*
Dinoprostone
Enterotoxins*
Epithelial Cells*
Humans*
Inflammation
Intestinal Mucosa
L-Lactate Dehydrogenase
NF-kappa B
Prostaglandin-Endoperoxide Synthases
Radioimmunoassay
RNA, Messenger
Cyclooxygenase 2
Dinoprostone
Enterotoxins
L-Lactate Dehydrogenase
NF-kappa B
Prostaglandin-Endoperoxide Synthases
RNA, Messenger