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PubMedDate not supplied

Measles is more prevalent in Crohn's disease patients. A multicentre Israeli study.

The question whether there is a transmissible pathogenetic agent as a cause for Crohn's disease, remains unanswered. Measles virus has been the subject of many intensive studies, in the attempt to find a role for it in the pathogenesis of inflammatory bowel disease. Whether an early infection with measles virus may predispose to Crohn's disease in later life is still not clear. We conducted a large scale multicentre study, in order to obtain sufficient data to answer this question. To do so, we compared inflammatory bowel disease patients, with Crohn's disease or ulcerative colitis, with two matched control groups: clinical controls, and community controls. A total of 531 patients, 271 with ulcerative colitis and 260 with Crohn's disease were interviewed, as well as 903 matched controls. Blood from 104 inflammatory bowel disease patients and 50 controls was tested for antibodies to measles virus. We did not find any differences related to measles vaccination, either in Crohn's disease or in ulcerative colitis. Exposure to measles in childhood was more frequent in Crohn's disease patients than in their controls, the difference being statistically significant (p < 0.05) in relation to community controls. The presence of IgG antibodies to measles virus was higher in patients with Crohn's disease than in patients with ulcerative colitis or controls (p = 0.084). Another observation of interest was the finding that Crohn's disease patients who had measles in childhood, more frequently had large bowel disease than those who had not had measles. These data lead us to postulate that there may be a role for measles infection in Crohn's disease, even if, at present, this role remains unclear.

Adult↗

PubMedDate not supplied

Human HT-29 colon carcinoma cells: mucin production and tumorigenicity in relation to growth phases.

The main aim of this study was to determine whether changes in mucin production/secretion during the growth phases of a human adenocarcinoma cell line, HT-29, are associated with a different tumorigenic potential. HT-29 cells cultured in DMEM supplemented with 10% FCS were harvested in the exponential and post-confluent phases of growth. Metabolic labeling of the cells was performed using [3H]-glucosamine. Following a 24 hr-incubation period, radioactivity was measured in 1 ml-aliquots of cell cytosol and culture medium. Concurrently, mucin synthesis was assessed by size exclusion chromatography of [3H]-glucosamine-labeled glycoprotein in a Sepharose CL-4B column. Clonigenic assay in soft agar of pre- and post-confluent HT-29 cells was determined by scoring viable colonies according to size and number using phase-contrast microscopy. To assess in vivo tumorigenicity, pre-and post-confluent HT-29 cells (4 x 10(6)) in 0.2 ml DMEM were inoculated into nude mice. Tumor size and volume were recorded for 31 days. H-29 cells grew as multilayers of unpolarized, undifferentiated cells. Colony forming efficiency was similar at all growth stages. A significant increase in mucin synthesis was noted in HT-29 cells harvested in the exponential phase of growth compared to the stationary phase (148.3 +/- 41.9 versus 49.1 +/- 5.0, mean +/- SE, dpm/4 x 10(3) cells, p < 0.05). Mucin secretion was not significantly changed. Tumorigenicity in nude mice was consistently higher when the cells were injected in the exponential phase of growth. On day 31 after cell inoculation the average tumor volume/site was 332.7 mm3 in mice injected with HT-29 cells in log phase compared to 142.7 mm3 (p < 0.01) in animals which received post-confluent cells. Tumor weights were 0.36 g and 0.22 g respectively (p < 0.05). The present results indicate a definitive correlation between growth phases of HT-29 cells and mucin synthesis: mucin production was significantly higher in exponentially growing cells. The cloning efficiency in soft agar, a marker of in vitro tumorigenicity, was similar in HT-29 cells irrespective of the growth stage. A main finding of the present study was the increased in vivo tumorigenicity of colon cancer cells inoculated into athymic mice in the log phase of growth compared to cells harvested at post-confluence. These results are consistent with the view that mucin plays an important contributory role in determining tumorigenicity.

Animals↗