Data regarding the chronological changes in gastric mucosal
cytokines in the different phases of Helicobacter pylori
infection are unavailable. We examined Mongolian gerbils for up to 52 weeks after H. pylori (ATCC 43504) inoculation. Levels of mRNAs of mucosal
cytokines (
interleukin-1beta [IL-1beta],
gamma interferon [IFN-gamma], IL-4, IL-6, and IL-10) were assessed using real-time reverse transcription-PCR. Starting 26 weeks after H. pylori inoculation, two clinicohistologic patterns appeared:
gastric ulcers in 32% and hyperplastic
polyps in 68% of gerbils. High levels of mucosal IL-1beta
mRNA were observed early in the
infection, reaching maximum at 4 weeks and then rapidly declining. Mucosal IFN-gamma
mRNA also reached maximal levels at 4 weeks but remained high thereafter. Both IL-1beta and IFN-gamma
mRNA levels were consistently higher in the pyloric mucosa than in the fundic mucosa. In contrast,
IL-4,
IL-6, and
IL-10 mRNA levels peaked at 8 to 26 weeks and levels were similar in the pyloric mucosa and the fundic mucosa. IFN-gamma
mRNA levels were significantly higher in gerbils with
ulcers than in those with hyperplastic
polyps (median IFN-gamma/
glyceraldehyde-3-phosphate dehydrogenase ratio x 100,000 = 650 versus 338, respectively [antrum], and 172 versus 40, respectively [corpus]) (P < 0.05). We propose that the different outcomes (e.g.,
ulcers or hyperplastic
polyps) might relate to imbalances among
cytokines.