Standard management protocol to improve the short-term outcome of biliary atresia.

AIM: This study compared the outcomes of patients with biliary atresia (BA) treated according to a standardised protocol with historical patients. METHODS: This is a single-centred retrospective study of BA patients treated from 1980 to 2016. A standardised treatment protocol was established since 2008 regarding peri-operative management. The outcomes being compared between the two groups (Groups I and II = before and after 2008, respectively) were jaundice clearance (JC), incidence of recurrent cholangitis, hospital admission and native liver survival (NLS). RESULTS: A total of 128 patients were included (Group I = 100, Group II = 28). The overall median follow-up period was 15.3 years (I vs. II = 20.6 years vs. 5.1 years, respectively). There was no significant difference in the JC at the sixth month between the two groups (I vs. II = 60.0 vs. 82.1%, respectively, P = 0.07). The incidence of recurrent cholangitis was similar between the two groups (I vs. II = 39 vs. 35.7%, respectively, P = 0.45), but the median hospital admission episode per patient was non-significantly higher in Group I (I vs. II = 4.2 vs. 2.7, respectively, P = 0.08). There was an improvement in the 1-year NLS rate in Group II (I vs. II = 69.0 vs. 85.7%, respectively, P = 0.05). CONCLUSIONS: The introduction of a standardised management protocol has improved the short-term outcome of BA patients, with a better 1-year NLS observed.

Downregulation of Hes1 expression in experimental biliary atresia and its effects on bile duct structure.

AIM: To analyze the expression and function of the Notch signaling target gene Hes1 in a rhesus rotavirus-induced mouse biliary atresia model. METHODS: The morphologies of biliary epithelial cells in biliary atresia patients and in a mouse model were examined by immunohistochemical staining. Then, the differential expression of Notch signaling pathway-related molecules was investigated. Further, the effects of the siRNA-mediated inhibition of Hes1 expression were examined using a biliary epithelial cell 3D culture system. RESULTS: Both immature (EpCAM+) and mature (CK19+) biliary epithelial cells were detected in the livers of biliary atresia patients without a ductile structure and in the mouse model with a distorted bile duct structure. The hepatic expression of transcripts for most Notch signaling molecules were significantly reduced on day 7 but recovered to normal levels by day 14, except for the target molecule Hes1, which still exhibited lower mRNA and protein levels. Expression of the Hes1 transcriptional co-regulator, RBP-Jκ was also reduced. A 3D gel culture system promoted the maturation of immature biliary epithelial cells, with increased expression of CK19+ cells and the formation of a duct-like structure. The administration of Hes1 siRNA blocked this process. As a result, the cells remained in an immature state, and no duct-like structure was observed. CONCLUSION: Our data indicated that Hes1 might contribute to the maturation and the cellular structure organization of biliary epithelial cells, which provides new insight into understanding the pathology of biliary atresia.

Uncovering the genetic lesions underlying the most severe form of Hirschsprung disease by whole-genome sequencing.

Hirschsprung disease (HSCR) is a complex birth defect characterized by the lack of ganglion cells along a variable length of the distal intestine. A large proportion of HSCR patients remain genetically unexplained. We applied whole-genome sequencing (WGS) on 9 trios where the probands are sporadically affected with the most severe form of the disorder and harbor no coding sequence variants affecting the function of known HSCR genes. We found de novo protein-altering variants in three intolerant to change genes-CCT2, VASH1, and CYP26A1-for which a plausible link with the enteric nervous system (ENS) exists. De novo single-nucleotide and indel variants were present in introns and non-coding neighboring regions of ENS-related genes, including NRG1 and ERBB4. Joint analysis with those inherited rare variants found under recessive and/or digenic models revealed both patient-unique and shared genetic features where rare variants were found to be enriched in the extracellular matrix-receptor (ECM-receptor) pathway (p = 3.4 × 10-11). Delineation of the genetic profile of each patient might help finding common grounds that could lead to the discovery of shared molecules that could be used as drug targets for the currently ongoing cell therapy effort which aims at providing an alternative to the surgical treatment.