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Gastric juice contains both pancreatic group I phospholipase A2 (PLA2-I) and synovial-type group II phospholipase A2 (PLA2-II), which may play a crucial role in Helicobacter pylori infection and gastric mucosal injury. PLA2-I present in gastric juice is derived from pancreatic acinar cells. The cellular source of PLA2-II found in gastric juice is unknown. A specific cell type of the intestinal mucosa, the Paneth cell, is known to secrete PLA2-II. The purpose of the present study was to define the source of PLA2-II present in gastric juice. For this purpose, gastric juice was collected from 29 individuals during gastroscopy, and mucosal biopsies were taken from the antrum and body of the stomach and from the duodenum as well as from the jejunum of individuals with resected stomach, for immunohistochemical detection of PLA2-II. The concentration of bilirubin in the gastric juice samples was determined to identify duodenogastric regurgitation. The PLA2-II content was significantly higher in bilirubin-positive than in bilirubin-negative gastric juice samples. PLA2-II was localized by immunohistochemistry in Paneth cells in three patients with areas of intestinal metaplasia of the gastric mucosa and in Paneth cells of duodenal and jejunal mucosa in all patients, but not in any other epithelial cell type of the mucosa of the stomach or the small intestine. Inflammatory cells did not contain PLA2-II. The current results suggest that PLA2-II found in gastric juice is derived from the Paneth cells of the small intestinal mucosa.

Group II phospholipase A2 is involved in the pathogenesis of various inflammatory diseases and in the host defence against bacteria. The enzyme is expressed in the epithelial cells of colonic mucosa in ulcerative colitis. In this study, we measured the concentration of group II phospholipase A2 in serum and colonic mucosa of patients with ulcerative colitis of different severity and of control patients without any inflammatory disease. The activity of ulcerative colitis was assessed by endoscopy. The concentration of group II phospholipase A2 was measured with an immunoassay. The concentrations of group II phospholipase A2 in serum and colonic mucosa were significantly higher in patients with active and inactive ulcerative colitis than in controls. However, the group II phospholipase A2 levels did not separate patients with different disease activity. The concentration of group II phospholipase A2 in colonic mucosa corresponded with the mucosal inflammatory activity (higher in active colonic areas) intra-individually, but not between different patients with ulcerative colitis. Serum group II phospholipase A2 values were above the normal reference range more often than the values of 11 standard laboratory blood tests widely used for the follow-up of inflammatory activity in ulcerative colitis. These results indicate that the concentration of group II phospholipase A2 is increased in serum and colonic mucosa of patients with ulcerative colitis. The clinical value of the measurement of group II phospholipase A2 in the follow-up of ulcerative colitis remains to be clarified.

Group II phospholipase A2 has been proposed to play an important role in the pathophysiology of inflammatory bowel diseases. This enzyme has also been linked to host defence mechanisms against bacteria. The current study aimed at measuring the mass concentrations of group II phospholipase A2 in serum and colonic mucosa of patients with Crohn's disease of different severity and of appropriate control patients without any inflammatory disease. The activity of the disease was determined by clinical factors (the simple index score) and endoscopic and histological scoring. The mass concentration of group II phospholipase A2 was measured by a time-resolved fluoroimmunoassay. The mass concentrations of group II phospholipase A2 in serum and colonic mucosa were significantly higher both in patients with active and inactive Crohn's disease when compared with controls. There was statistically significant difference in the mass concentration of group II phospholipase A2 in colonic mucosa but not in serum between inactive and active Crohn's disease. The current results indicate that the mass concentration of group II phospholipase A2 is increased in serum and colonic mucosa of patients with Crohn's disease and that the latter is associated with the degree of the inflammatory activity in the intestinal wall. These results support the idea that group II phospholipase A2 is involved in the local and generalised pathological processes of Crohn's disease.

Increased mucosal concentration of bactericidal/permeability-increasing protein (BPI) has been shown in inflammatory bowel diseases. The purpose of the present study was to investigate the relationship between the mucosal concentration of BPI and the grade of mucosal inflammation in ulcerative colitis.Samples of colonic mucosa from 12 patients with ulcerative colitis and from 8 control patients were studied. The concentration of BPI in tissue extracts was measured by a time-resolved fluoroimmunoassay. The concentration of BPI was compared between samples with histological inflammatory changes of different severity. BPI was localized in tissue sections by immunohistochemistry.The concentration of BPI was higher (p0.001) in samples of colonic mucosa from patients with ulcerative colitis (median: 3.2 micrograms/g, range: 0.3-22.6 micrograms/g) than in control samples (0.4 microgram/g, 0.1-0.6 microgram/g,). Moreover, the concentration of BPI was higher (p = 0.015) in samples with severe inflammation (2.5 mu/g, 0.3-22.6 micrograms/g) than in those with mild inflammation (0.5 mu/g, 0.3-2.5 micrograms/g). The concentration of BPI in mucosal samples correlated well with the degree of histological inflammation (Spearman R = 0.70, p = 0.01). BPI was localized in polymorphonuclear leukocytes in the mucosa and stroma of the colonic wall.The concentration of BPI is increased in the colonic mucosa of patients with ulcerative colitis. The increase in the concentration of BPI in colonic mucosa seems to be closely associated with the inflammatory activity of ulcerative colitis.

Phospholipase A2 (PLA2) has been suggested to play an important role in the pathogenesis of inflammatory bowel diseases. Our aim was to identify cells that express group II phospholipase A2 (PLA2-II) at the mRNA and enzyme protein levels in the intestine in Crohn's disease.Tissue samples were obtained from the intestine of 20 patients with Crohn's disease (seven operated and 13 colonoscopied) and from eight control patients without inflammatory diseases. The samples were studied by immunohistochemistry for PLA2-II enzyme protein and in situ hybridization for PLA2-II mRNA.PLA2-II protein and mRNA were detected in the Paneth cells of the small intestinal mucosa in all patients and controls. PLA2-II protein and mRNA were found in the columnar epithelial cells of the small intestinal mucosa in six of eight and eight of eight patients with Crohn's ileitis, respectively. In the eight control patients PLA2-II protein and mRNA were not found in these cells (p = 0.007 and p0.001, respectively). Metaplastic Paneth cells, which consistently contained PLA2-II mRNA, were found in the colonic mucosa in five of six patients with Crohn's colitis and of one of eight control patients (p = 0.026). The columnar epithelial cells of the colonic mucosa contained PLA2-II protein in three of six and PLA2-II mRNA in six of six patients with Crohn's colitis, whereas the protein was found in these cells in none of eight of the controls (p = 0.055) and the mRNA in only one of eight (p = 0.005) controls.In Crohn's disease, Paneth cells and columnar epithelial cells of the small and large intestinal mucosa synthesize PLA2-II at the site of active inflammation.

Group II phospholipase A2 has been proposed to play an important role in the pathophysiology of inflammatory bowel diseases. This enzyme has also been linked to host defence mechanisms against bacteria. The current study aimed at measuring the mass concentrations of group II phospholipase A2 in serum and colonic mucosa of patients with Crohn's disease of different severity and of appropriate control patients without any inflammatory disease. The activity of the disease was determined by clinical factors (the simple index score) and endoscopic and histological scoring. The mass concentration of group II phospholipase A2 was measured by a time-resolved fluoroimmunoassay. The mass concentrations of group II phospholipase A2 in serum and colonic mucosa were significantly higher both in patients with active and inactive Crohn's disease when compared with controls. There was statistically significant difference in the mass concentration of group II phospholipase A2 in colonic mucosa but not in serum between inactive and active Crohn's disease. The current results indicate that the mass concentration of group II phospholipase A2 is increased in serum and colonic mucosa of patients with Crohn's disease and that the latter is associated with the degree of the inflammatory activity in the intestinal wall. These results support the idea that group II phospholipase A2 is involved in the local and generalised pathological processes of Crohn's disease.

BACKGROUND: It has been suggested that phospholipase A2 (PLA2) has an essential role in the pathogenesis of inflammatory bowel diseases. AIMS: This study aimed at identifying cells in intestinal and mesenteric tissue samples that might express group II phospholipase A2 (PLA2-II) at the mRNA and enzyme protein levels in patients with ulcerative colitis. PATIENTS AND TISSUE SAMPLES: Tissue samples were obtained from the intestine, mesentery, skeletal muscle, and subcutaneous fat of six patients who underwent panproctocolectomy for severe ulcerative colitis. Mucosal biopsy specimens were obtained from the colon of another group of six patients with ulcerative colitis during routine diagnostic colonoscopies. Tissues from six patients without intestinal inflammatory diseases served as controls. METHODS: Tissue samples were studied by light microscopy, immunohistochemistry for PLA2-II enzyme protein, and in situ hybridisation and northern hybridisation for PLA2-II mRNA. RESULTS: PLA2-II mRNA and PLA2-II protein were detected in metaplastic Paneth cells in six patients and in the columnar epithelial cells of colonic mucosa in four out of six patients with active ulcerative colitis. Positive findings were less numerous in patients with mild ulcerative colitis. Only two out of six control patients had a weak positive signal for PLA2-II mRNA and one of these two patients had a weak positive immunoreaction for PLA2-II in columnar epithelial cells in the colonic mucosa. None of the control patients had metaplastic Paneth cells. CONCLUSIONS: Metaplastic Paneth cells and colonic epithelial cells synthesise PLA2-II in ulcerative colitis. The activity of the PLA2-II synthesis seems to be related to the degree of inflammation in the diseased bowel.

Summary: A major role has been proposed for group II phospholipase A2 in the pathogenesis of local and generalised inflammatory reactions. Elevated catalytic activity and mass concentrations of this enzyme have been found in serum and tissue samples of the colon in patients with active ulcerative colitis. The cellular source(s) of group II phospholipase Az in the blood circulation is (are) unknown. In the current prospective study, we investigated the mass concentration of group II phospholipase AI and the catalytic activity concentration of phospholipase AI in serial serum samples of 15 consecutive patients who underwent a standard panproctocolectomy operation for severe ulcerative colitis. Both the catalytic activity concentrations of phospholipase A2 and the mass concentrations of group II phospholipase AI increased rapidly in serum samples to maximum values on the first postoperative day and then decreased (p = 0.002 and p < 0.001, respectively) in patients who recovered uneventfully. Three patients had postoperative complications that further increased the enzyme concentrations at the time of respective complications. The pattern of group II phospholipase Az mass concentration profiles was similar to the profiles of C-reactive protein. The results show that the removal of the large bowel does not eliminate the potential to secrete group II phospholipase AZ into the blood circulation in these patients. Secretion of group II phospholipase A2 into the circulation after surgery seems to be a normal host response to a major abdominal operation and postoperative complications. Consequently, we conclude that the large bowel is not an important source of group II phospholipase AZ in sera of patients with ulcerative colitis. The results also support the assumptions that the catalytic activity of phospholipase A2 in serum is attributable to group II phospholipase A2 and that this enzyme is an acute phase protein.