PANCREATITIS-ASSOCIATED PROTEIN IN PATIENTS WITH CELIAC-DISEASE - SERUM LEVELS AND IMMUNOCYTOCHEMICAL LOCALIZATION IN SMALL-INTESTINE

Since PAP is a stress protein expressed in human pancreas during pancr eatitis but also constitutively synthesized in the small intestine, we looked whether its expression would be altered in patients with celia c disease. Serum PAP concentrations were determined consecutively in 5 4 patients with celiac disease on a free diet (group A), in 47 patient s with celiac disease on a gluten-free diet (group B), in 22 patients with other intestinal pathologies but with normal intestinal mucosa (g roup C), in 14 patients with retarded growth, no gastrointestinal dise ase and normal intestinal mucosa (group D), and in 17 controls (group E). Serum PAP levels (ng/ml) were significantly higher in group A (127 .3 +/- 56.8) than in the other groups (B: 47.2 +/- 20.5; C: 51.5 +/- 3 2.2; D: 47 +/- 22.8; E: 27.6 +/- 9.0), which were not different from e ach other. In group A, a positive correlation was observed between ser um PAP values and antigluten antibody levels (vs. AGA IgG r = 0.58, p < 0.001; vs. AGA IgA r = 0.66, p < 0.001). Furthermore, 12 patients fr om group A were evaluated after 10-12 months of gluten-free diet and i n all of them PAP serum concentration had decreased (mean +/- SE befor e the diet 122.5 +/- 36.4, after the diet 48.7 +/- 13.7, p < 0.0001). In addition, we performed an immunocytochemical study to localize PAP in the intestinal mucosa of patients from all groups except E. PAP was localized to the Paneth cells and to some globet cells, in patients w ith mucosal atrophy as well as in those with normal mucosa with no obv ious quantitative difference. We concluded that in patients with celia c disease the active phase of the disease was accompanied by an increa sed serum concentration of PAP. Further studies are necessary to under stand the mechanism leading to PAP elevation in the serum of patients with celiac disease.