Lysozyme overexpression in fundic gland polyps.

Area of Science:

• Gastroenterology
• Pathology
• Microbiology

Background:

• Helicobacter pylori (Hp) infection is common, but its proliferation is notably rare in patients with fundic gland polyps (FGPs).
• FGPs exhibit expression of lysozyme, a key component of the innate immune system involved in combating microbial infections.

Purpose of the Study:

• To investigate and quantify the expression levels of lysozyme in fundic gland polyps (FGPs).
• To correlate lysozyme expression patterns with the presence or absence of Helicobacter pylori (Hp) infection.

Main Methods:

• Analysis of 153 gastric biopsies, including FGPs, normal mucosa, Hp-induced gastritis, and non-Hp gastritis.
• Immunohistochemical staining using anti-lysozyme (muramidase) antibodies to assess lysozyme distribution and intensity.

Main Results:

• Lysozyme expression was observed in various gastric tissues, with marked expression in neck glands of normal mucosa and gastritis.
• A higher ratio of lysozyme in neck glands compared to foveoli was noted in non-Hp gastritis and Hp-gastritis.
• FGPs demonstrated significant lysozyme expression in surface epithelium, foveolar pits, and cyst-lining cells.

Conclusions:

• The elevated lysozyme production in the epithelium of FGPs may serve as a protective mechanism against Helicobacter pylori proliferation.
• While lysozyme in gastritis may not be sufficient for bacterial eradication, its overproduction in FGPs offers a potential explanation for the low incidence of Hp infection in these polyps.