Differential cathelicidin expression in duodenal and gastric biopsies from Tanzanian and German patients.

Epithelial surfaces such as the gastrointestinal mucosa depend on
expression of antimicrobial peptides like cathelicidin for immune
defence against pathogens. The mechanisms behind mucosal
cathelicidin regulation are incompletely understood. Cathelicidin
expression was analysed in duodenal, antral and corpus/fundic
mucosal biopsies from African and German patients. Additionally,
cathelicidin expression was correlated with Helicobacter pylori
(HP) infection and the inflammatory status of the mucosa. High
cathelicidin transcript abundance was detected in duodenal biopsies
from African subjects. On the contrary, cathelicidin mRNA
expression was either undetectable or very low in tissue specimens
from German patients. Also, in the antrum and corpus/fundus regions
of the stomach significantly higher cathelicidin transcript levels
were measured in Tanzanian compared to German patients. In gastric
biopsies from African patients cathelicidin expression was
increased in HP positive compared to HP negative subjects.
Additionally, the inflammatory status measured by IL-8 expression
correlated well with the HP infection status. A higher duodenal and
gastric cathelicidin expression in African (compared with European)
individuals may be due to upregulation by antigenic stimulation and
may confer a higher resistance against enteric infections.