Leina Alrabadi, MD

Abstract

BACKGROUND: Oral vancomycin (OV) in primary sclerosing cholangitis (PSC) has been evaluated as a potential therapeutic agent. We report the long-term biochemical course and outcomes of patients with PSC treated with OV.METHODS: Patients were enrolled in 2 open-label clinical trials (ClinicalTrials.gov Identifier: NCT01802073 and NCT01322386) and offered OV at 50mg/kg/day in 3 divided doses if weight <30kg, and 500mg 3 times/day if weight 30kg. Patients with biliary strictures requiring stenting or awaiting liver transplant were excluded. Liver biochemistry, MRCP and histology were documented at baseline and while on OV. The primary outcome was a decrease in elevated gamma glutamyl transferase (GGT), alkaline phosphatase (ALP), and/or alanine aminotransferase (ALT) from baseline.RESULTS: 30 subjects were enrolled, and 29 additional subjects who learned of the clinical trial requested OV (total n=59; median age was 13.5years [range, 1.5-44years]; 64.4% were male; and 94.9% had inflammatory bowel disease [IBD]). The median treatment duration was 2.7years (range, 0.2-14years). Ninety-six percent (57/59), 81.3% (48/59), and 94.9% (56/59) experienced reduction of GGT, ALP, and ALT, respectively. Furthermore, 39% (23/59), 22% (13/59), and 55.9% (33/59) experienced normalization of GGT, ALP, and ALT, respectively, within the first 6months of OV treatment. One patient underwent liver transplantation 8years after beginning OV treatment, and one developed biliary strictures requiring endoscopic intervention. OV was well-tolerated by patients, and no patient developed treatment-related adverse events.CONCLUSION: In PSC, OV was well-tolerated and was associated with improvement in liver chemistry. A randomized placebo-controlled clinical trial is warranted.

View details for DOI 10.1080/00365521.2020.1787501

View details for PubMedID 32633158

Abstract

Primary sclerosing cholangitis (PSC) is a heterogeneous and progressive fibroinflammatory cholangiopathy with no known etiology or effective treatment. Studies of PSC are limited due to difficulty in accessing the cholangiocyte, the small percentage of these cells in the liver, instability of in vitro culture systems, and reliance on samples from end-stage disease. Here, we demonstrate that stem cells can be isolated from the bile of PSC patients undergoing endoscopic retrograde cholangiopancreatography earlier in their clinical course and maintained long term in vitro as three-dimensional (3D) organoids that express a biliary genetic phenotype. Additionally, bile-derived organoids (BDOs) can be biobanked and samples obtained longitudinally over the course of the disease. These BDOs express known cholangiocyte markers including gamma glutamyl transferase, cytokeratin 19, epithelial cellular adhesion molecule, cystic fibrosis transmembrane conductance regulator, and anion exchanger 2. RNA sequence analysis identified 39 genes whose expression differed in organoids from PSC patients compared to non-PSC controls, including human leukocyte antigen DM alpha chain and chemokine (C-C motif) ligand 20 (CCL20), immune-related genes previously described in genome-wide association studies of PSC. Incubation of these BDOs with interleukin 17A or tumor necrosis factor alpha led to an immune-reactive phenotype with a significant increase in secretion of proinflammatory mediators, including CCL20, a T-cell chemoattractant. Conclusion: This study demonstrates that bile can be used as a source of biliary-like cells that can be maintained long term in vitro as 3D organoids; these BDOs retain features of cholangiopathies, including the ability to react to inflammatory stimuli by secreting chemokines and propagating an immune-reactive phenotype reflective of the pathogenesis of these diseases; thus, BDOs represent a platform for the study of the pathogenesis and therapy of cholangiopathies, particularly PSC.

View details for DOI 10.1002/hep.30470

View details for PubMedID 30561836

View details for DOI 10.1177/0009922819832034

View details for Web of Science ID 000466124900017

View details for PubMedID 30788983

View details for Web of Science ID 000446020503126

View details for Web of Science ID 000446020503191

Abstract

An evidence-practice gap for use of celiac disease testing can lead to poor resource utilization. False positive tests may lead to unnecessary diet changes, gastroenterology consults, parental/patient concern, and additional testing and expenses complicated by varied available celiac bundles. An understanding of pediatric provider practices according to guideline recommendations further improves this gap.

View details for DOI 10.1177/0009922818769453

View details for Web of Science ID 000440685200009

View details for PubMedID 29667919

Abstract

Development of macrovesicular steatosis post-LT in patients with PFIC-1 is increasingly being observed, with the etiology not fully understood. We highlight successful and effective EBD for reversal of allograft steatosis in 2 patients with PFIC-1 disease and discuss our experience with internal biliary diversion in this patient population.

View details for DOI 10.1111/petr.13184

View details for Web of Science ID 000433590800014

View details for PubMedID 29654655

View details for Web of Science ID 000412089800110

Abstract

Obesity is an important risk factor for colon cancer in humans, and numerous studies have shown that a high fat diet enhances colon cancer development. As both increased adiposity and high fat diet can promote tumorigenesis, we examined the effect of diet-induced obesity, without ongoing high fat diet, on colon tumor development. C57BL/6J male mice were fed regular chow or high fat diet for 8 weeks. Diets were either maintained or switched resulting in four experimental groups: regular chow (R), high fat diet (H), regular chow switched to high fat diet (RH), and high fat diet switched to regular chow (HR). Mice were then administered azoxymethane to induce colon tumors. Tumor incidence and multiplicity were dramatically smaller in the R group relative to all groups that received high fat diet at any point. The effect of obesity on colon tumors could not be explained by differences in aberrant crypt foci number. Moreover, diet did not alter colonic expression of pro-inflammatory cytokines tumor necrosis factor-, interleukin-6, interleukin-1, and interferon-, which were measured immediately after azoxymethane treatment. Crypt apoptosis and proliferation, which were measured at the same time, were increased in the HR relative to all other groups. Our results suggest that factors associated with obesity - independently of ongoing high fat diet and obesity - promote tumor development because HR group animals had significantly more tumors than R group, and these mice were fed the same regular chow throughout the entire carcinogenic period. Moreover, there was no difference in the number of aberrant crypt foci between these groups, and thus the effect of obesity appears to be on subsequent stages of tumor development when early preneoplastic lesions transition into adenomas.

View details for DOI 10.1371/journal.pone.0060939

View details for Web of Science ID 000318840100109

View details for PubMedID 23560112

View details for PubMedCentralID PMC3616169

Abstract

Neurotensin receptor-1 (NTR-1) is overexpressed in colon cancers and colon cancer cell lines. Signaling through this receptor stimulates proliferation of colonocyte-derived cell lines and promotes inflammation and mucosal healing in animal models of colitis. Given the causal role of this signaling pathway in mediating colitis and the importance of inflammation in cancer development, we tested the effects of NTR-1 in mouse models of inflammation-associated and sporadic colon cancer using NTR-1-deficient (Ntsr1(-) (/-)) and wild-type (Ntsr1(+/+)) mice. In mice treated with azoxymethane (AOM) to model sporadic cancer, NTR-1 had a significant effect on tumor development with Ntsr1(+/+) mice developing over twofold more tumors than Ntsr1(-) (/-) mice (p = 0.04). There was no effect of NTR-1 on the number of aberrant crypt foci or tumor size, suggesting that NT/NTR-1 signaling promotes the conversion of precancerous cells to adenomas. Interestingly, NTR-1 status did not affect tumor development in an inflammation-associated cancer model where mice were treated with AOM followed by two cycles of 5% dextran sulfate sodium (DSS). In addition, colonic molecular and histopathologic analyses were performed shortly after a single cycle of DSS. NTR-1 status did not affect colonic myeloperoxidase activity or histopathologic scores for damage and inflammation. However, Ntsr1(-) (/-) mice were more resistant to DSS-induced mortality (p = 0.01) and had over twofold higher colonic expression levels of Il6 and Cxcl2 (p < 0.04), cytokines known to promote tumor development. These results represent the first direct demonstration that targeted disruption of the Ntsr1 gene reduces susceptibility to colon tumorigenesis.

View details for DOI 10.1002/ijc.26208

View details for Web of Science ID 000300692300009

View details for PubMedID 21630261

View details for PubMedCentralID PMC3288327

View details for Web of Science ID 000290167303612