Pathologic changes in the liver and kidney produced by immunization with intestinal antigens

Area of Science:

• Immunology
• Gastroenterology
• Nephrology

Background:

• Inflammatory bowel disease (IBD) in humans is associated with extraintestinal manifestations like chronic active hepatitis and interstitial nephritis.
• The underlying mechanisms for these extraintestinal conditions are not fully understood.

Purpose of the Study:

• To investigate the role of shared antigens in the pathogenesis of liver and kidney inflammation.
• To explore a potential animal model for studying extraintestinal manifestations of IBD.

Main Methods:

• Rabbits were immunized with intestinal antigens from rabbits, guinea pigs, and germfree rats.
• Control rabbits were immunized with nonintestinal antigens.
• Liver and kidney tissues were examined for inflammatory changes.

Main Results:

• 55% of rabbits receiving intestinal antigens showed portal tract inflammation in the liver.
• 7 out of 23 rabbits developed interstitial nephritis.
• No such changes were observed in control rabbits immunized with nonintestinal antigens.
• A shared antigen was identified in the liver, kidney, and various intestinal tissues across species.

Conclusions:

• An immune response to shared antigens between intestinal and other tissues may contribute to the observed liver and kidney inflammation in this rabbit model.
• This experimental system may provide insights into the pathogenesis of extraintestinal manifestations in human inflammatory bowel disease.