Gastric epithelial anti-microbial peptides--histological correlation and influence of anatomical site and peptic ulcer disease.
OBJECTIVE
Natural anti-microbial peptides are increasingly recognised for their protective effects in mucosal surfaces. We, therefore, aimed at investigating their expression in the human stomach in a range of peptic conditions.


METHODS
We assessed the expression of epithelial secretory leukocyte protease inhibitor, human beta-defensins (HBD1 and HBD2), and alpha-defensin (HD5) in gastric biopsies taken from 52 patients, median age of 55 years. Expression of peptide mRNA was determined using real-time quantitative polymerase chain reaction. The activity of gastritis was graded on a 0-3 scale.


RESULTS
The antrum had a median secretory leukocyte protease inhibitor of 0.93 and HBD1 of 0.42, compared with 0.13 (P = 0.001) and 0.08 units (P = 0.002) respectively in the gastric body. The antral histological scores correlated positively with HBD2 expression (r = 0.69; P< 0.001) and negatively with HBD1 (r = -0.47; P = 0.006) particularly in the absence of aspirin. Patients with Helicobacter pylori gastritis, gastric or duodenal ulcers had lower expression of HBD1 and greater expression of HBD2 than in controls. The intake of aspirin by patients infected with H. pylori was associated with marked rise in the expression of HD5 and less expression of secretory leukocyte protease inhibitor.


CONCLUSIONS
Gastric epithelial anti-microbial peptides are influenced by anatomical site, grade of gastritis, peptic ulceration, and can be modulated by aspirin.
Taha
A S
AS
The Gastroenterology Service, Crosshouse Hospital, Kilmarnock KA20BE, Scotland, UK. ali.taha1@btinternet.com
Faccenda
E
E
Angerson
W J
WJ
Balsitis
M
M
Kelly
R W
RW
D000293:Adolescent; D000328:Adult; D004381:Duodenal Ulcer / Q000378:metabolism*; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D053491:Proteinase Inhibitory Proteins, Secretory; D011506:Proteins / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013276:Stomach Ulcer / Q000378:metabolism*; D023084:alpha-Defensins / Q000378:metabolism*; D023083:beta-Defensins / Q000378:metabolism*
C406407:DEFB1 protein, human; C106641:DEFB4A protein, human; D053491:Proteinase Inhibitory Proteins, Secretory; D011506:Proteins; D023084:alpha-Defensins; D023083:beta-Defensins