Pluripotent plasticity of stem cells and liver repopulation.

Different types of stem cells have a role in liver regeneration or fibrous repair during and after several liver diseases. Otherwise, the origin of hepatic and/or extra-hepatic stem cells in reactive liver repopulation is under controversy. The ability of the human body to self-repair and replace the cells and tissues of some organs is often evident. It has been estimated that complete renewal of liver tissue takes place in about a year. Replacement of lost liver tissues is accomplished by proliferation of mature hepatocytes, hepatic oval stem cells differentiation, and sinusoidal cells as support. Hepatic oval cells display a distinct phenotype and have been shown to be a bipotential progenitor of two types of epithelial cells found in the liver, hepatocytes, and bile ductular cells. In gastroenterology and hepatology, the first attempts to translate stem cell basic research into novel therapeutic strategies have been made for the treatment of several disorders, such as inflammatory bowel diseases, diabetes mellitus, celiachy, and acute or chronic hepatopaties. In the future, pluripotent plasticity of stem cells will open a variety of clinical application strategies for the treatment of tissue injuries, degenerated organs. The promise of liver stem cells lie in their potential to provide a continuous and readily available source of liver cells that can be used for gene therapy, cell transplant, bio-artificial liver-assisted devices, drug toxicology testing, and use as an in vitro model to understand the developmental biology of the liver.

Antiglycan antibodies as serological markers in the differential diagnosis of inflammatory bowel disease.

BACKGROUND: The objective of the study was to evaluate the diagnostic accuracy of recently developed antiglycan serological tests in clinical practice for the diagnosis of Crohn's disease. METHODS: This study was a cohort analysis of both clinical and biochemical parameters of patients with diagnosed inflammatory bowel disease compared with those in a control population. Antiglycan antibodies were determined using commercially available enzyme immunoassays. The setting was the outpatient unit of the gastroenterology department of a large, tertiary-care referral academic hospital. Participants were 214 consecutive patients, enrolled over a 5-month period, including 116 with Crohn's disease and 53 with ulcerative colitis, as well as 45 with other gastrointestinal diseases and 51 healthy controls. RESULTS: Anti-Saccharomyces cerevisiae antibodies showed the best performance (54% sensitivity and 88%-95% specificity for Crohn's disease). Among patients with negative anti-Saccharomyces antibodies, 19 (34%) had high titers of at least another tested antiglycan antibody. Anti-Saccharomyces and anti-laminaribioside antibodies were associated with disease involving the small bowel and with penetrating or stricturing phenotype. Anti-laminaribioside was significantly higher in patients with a familial history of inflammatory bowel disease. CONCLUSIONS: The new proposed serological markers are significantly associated with Crohn's disease, with low sensitivity but good specificity. About one third of anti-Saccharomyces-negative patients may be positive for at least 1 of those markers. Antiglycan antibodies appear to be associated with characteristic localization and phenotype of the disease.

Rapid cortisol assay during adrenal vein sampling in patients with primary aldosteronism.

BACKGROUND: Adrenal vein sampling is considered the gold standard test to identify primary aldosteronism, the most frequent form of secondary hypertension. Technical difficulties with this procedure may be overcome by monitoring cortisol concentrations in the different sampling sites during catheterization. METHODS: We applied a rapid automated cortisol assay performed on a benchtop immunoassay analyzer near the operating suite during the catheterization procedures in 5 hypertensive patients. A mean of 7.8 samples (range, 5-13) were collected from the vena cava as well as from right and left adrenal veins. RESULTS: Cortisol concentrations measured by the rapid assay and by our routine method were comparable. Two of 5 patients were found to be affected by an aldosterone-producing adenoma and 3 of 5 by a bilateral adrenal hyperplasia. Cortisol determination during the adrenal vein sampling procedure allowed a successful cannulation in all patients, including a patient in whom it was necessary to cannulate 9 different candidate right adrenal veins before finding the correct one. CONCLUSIONS: Intraoperative cortisol assays appeared safe, reproducible, simple to perform, rapid, and cost-effective. The approach represents a service-oriented model for the laboratory and can provide valuable and timely information for improving the success rate of adrenal vein catheterization.