Gastric mucosa-associated lymphoid tissue lymphoma: implications of animal models on pathogenic and therapeutic considerations--mouse models of gastric lymphoma.

There are a number of Helicobacter species that will readily colonise the mouse stomach for the duration of the animal's life. They are Helicobacter felis, "Helicobacter heilmannii" and Helicobacter pylori. Early studies on long-term infection of BALB/c mice showed the presence of lesions resembling low-grade gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Because of the suggestion that H. pylori was the cause of these tumors in humans, this phenomenon was studied further as it was reasoned that the Helicobacter-infected mice would provide a valuable model of the human disease. Low-grade gastric MALT lymphomas have been shown to follow infection with all the Helicobacter species listed above. These lesions are indistinguishable from the human disease with the presence of centrocyte-like cells, characteristic lymphoepithelial lesions and glandular destruction. Treatment with antimicrobial therapy results in regression of the lymphomas. There is evidence of progression to high-grade in some animals. The Helicobacter mouse models of lymphoma are likely to provide important information relevant not just to H. pylori-induced lesions in the human, but to antigen-driven tumors in general.