Previous Article | Next Article ![]()
Infect. Immun., 05 1996, 1565-1568, Vol 64, No. 5
JP Russell, G Diamond, AP Tarver, TF Scanlin and CL Bevins
Peptides with potent broad-spectrum antibiotic activity have been
identified in many animal species. Recent investigations have demonstrated
that epithelial cells are a site of antibiotic peptide expression,
suggesting that these peptides contribute to host defense at mucosal
surfaces. Expression of tracheal antimicrobial peptide (TAP), a member of
the beta-defensin family of peptides, is inducible in cultured tracheal
epithelial cells (TEC) upon challenge with bacterial lipopolysaccharide
(LPS) (G. Diamond, J.P. Russell, and C.L. Bevins, Proc. Natl. Acad. Sci.
USA, in press). In this study, an anchored reverse transcriptase PCR
strategy was used to determine if TAP was the sole beta-defensin isoform
expressed upon stimulation of the cells with LPS. In addition to TAP, a
second class of cDNA clones which encoded lingual antimicrobial peptide
(LAP), a beta-defensin peptide recently isolated from a different mucosal
site, the bovine tongue, was identified (B.S. Schonwetter, E.D.
Stolzenberg, and M. Zasloff, Science 267:1645-1648, 1995). Northern (RNA)
blot analysis demonstrated in vivo expression of LAP mRNA in tracheal
mucosa. Levels of LAP mRNA were higher in cultured TEC challenged with
either LPS or tumor necrosis factor alpha than in control cells. Thus, a
response of TEC exposed to inflammatory mediators is induction of
antibiotic- encoding genes, including both TAP and LAP. This work
complements the in vivo studies of Schonwetter et al. (cited above), which
showed elevated levels of LAP mRNA in squamous epithelial cells of the
tongue near sites of tissue injury and inflammation, by suggesting possible
mediators of the in vivo observation. Together these lines of
investigations support the hypothesis that inducible expression of
endogenous antibiotic peptides by inflammatory mediators characterizes
local defense of mammalian mucosal surfaces.
Copyright © 1996, American Society for Microbiology
Coordinate induction of two antibiotic genes in tracheal epithelial cells exposed to the inflammatory mediators lipopolysaccharide and tumor necrosis factor alpha
Division of Human Genetics and Molecular Biology, Children's Hospital of Philadelphia, PA 19104, USA.
This article has been cited by other articles:
| J. Bacteriol. | J. Virol. | Eukaryot. Cell |
|---|
| Microbiol. Mol. Biol. Rev. | Clin. Vaccine Immunol. | All ASM Journals |
|---|