Since oral lesions appear to occur more commonly in patients with Crohn's disease (CD) than in normal controls or patients with ulcerative colitis, it has been suggested that a deficit of locally produced IgA allows the invasion of the oral mucous membrane by antigens and contributes to the production of oral lesions. In connection with this hypothesis, the concentrations of IgA, IgM, and IgG in whole and parotid saliva were investigated by the ELISA technique in 20 patients with CD and 20 healthy subjects matched for dental status. IgA predominated in whole and parotid saliva in both patients and controls, and in both groups whole saliva had higher levels of IgA, IgM, and IgG than parotid saliva did. Compared with the controls, IgA, IgM, and IgG levels were significantly elevated in the whole saliva of CD patients. However, no correlation was found between immunoglobulin levels and age, sex, therapy, duration, localization, or activity of the disease.

SummaryPlasminogen activators were determined in intestinal tissue, obtained after surgery from patients with Crohn’s disease and ulcerative colitis, and compared with normal intestinal tissue from colorectal cancer patients.The activity and quantity of tissue-plasminogen activator (t-PA) was found to decrease with the severity of inflammation in the patients with inflammatory bowel disease. Urokinase (u-PA) activity, however, was not changed compared with controls or in relation with severity of inflammation. In contrast, the level of u-PA antigen was found to be increased significantly in the inflammatory bowel disease tissues and was also related with severity of inflammation. The difference between u-PA activity and antigen in inflammatory bowel disease tissue could be attributed to an increase in inactive pro-u-PA and u-PA-inhibitor complexes.This increase in u-PA and the concomitant decrease in t-PA, are similar to those found in premalignant colonic adenomas, and might be related to the known increased cancer risk in inflammatory bowel disease.