Hélène Gilgenkrantz

About 60% of both Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) is due to deletions of the dystrophin gene. For cases with a deletion mutation, the "reading frame" hypothesis predicts that BMD patients produce a semifunctional, internally deleted dystrophin protein, whereas DMD patients produce a severely truncated protein that would be unstable. To test the validity of this theory, we analyzed 258 independent deletions at the DMD/BMD locus. The correlation between phenotype and type of deletion mutation is in agreement with the "reading frame" theory in 92% of cases and is of diagnostic and prognostic significance. The distribution and frequency of deletions spanning the entire locus suggests that many "in-frame" deletions of the dystrophin gene are not detected because the individuals bearing them are either asymptomatic or exhibit non-DMD/non-BMD clinical features.

BACKGROUND: The effect of regression of cirrhosis in chronic hepatitis C is unknown. OBJECTIVE: To evaluate the relation between regression of cirrhosis and clinical outcome in patients with chronic hepatitis C after antiviral therapy. DESIGN: A cohort of patients with cirrhosis treated between 1988 and 2001. SETTING: Hepatology unit of a tertiary care center in France. PATIENTS: 96 patients with chronic hepatitis C and biopsy-proven cirrhosis (METAVIR score F4) who were treated with an interferon-based regimen and had at least 1 posttreatment liver biopsy. Patients were followed until November 2006. MEASUREMENTS: Occurrence of a combined end point of liver-related events (ascites, hepatic encephalopathy, variceal bleeding, spontaneous bacterial peritonitis, hepatocellular carcinoma, or liver transplantation) and death in patients with regression of cirrhosis (defined as a decrease from 4 to <or=2 METAVIR units on posttherapy liver biopsy). RESULTS: The median follow-up was 118 months (interquartile range, 86 to 138 months). Eighteen patients had regression of cirrhosis. The incidence of the combined end point per 100 patient-years was 0 in patients with regression of cirrhosis and 4 in patients without regression of cirrhosis (P = 0.002, log-rank test). The transplantation-free survival rate at 10 years was 100% in patients with regression of cirrhosis and 74.2% in patients without regression of cirrhosis (P = 0.025). LIMITATIONS: Selection of patients was retrospective; selection and survival biases may have influenced the estimates of the overall rate of regression of cirrhosis. The low number of patients who experienced regression of cirrhosis precludes analysis of factors that could predict regression of cirrhosis. CONCLUSION: Regression of cirrhosis occurs after antiviral therapy in some patients with chronic hepatitis C. Regression is associated with decreased disease-related morbidity and improved survival.

Liver fibrosis is the common response to chronic liver injury, and leads to cirrhosis and its complications. Persistent inflammation is a driving force of liver fibrosis progression. Mucosal-associated invariant T (MAIT) cells are non-conventional T cells that display altered functions during chronic inflammatory diseases. Here, we show that circulating MAIT cells are reduced in patients with alcoholic or non-alcoholic fatty liver disease-related cirrhosis while they accumulate in liver fibrotic septa. Using two models of chronic liver injury, we demonstrate that MAIT cell-enriched mice show increased liver fibrosis and accumulation of hepatic fibrogenic cells, whereas MAIT cell-deficient mice are resistant. Co-culture experiments indicate that MAIT cells enhance the proinflammatory properties of monocyte-derived macrophages, and promote mitogenic and proinflammatory functions of fibrogenic cells, via distinct mechanisms. Our results highlight the profibrogenic functions of MAIT cells and suggest that targeting MAIT cells may constitute an attractive antifibrogenic strategy during chronic liver injury.