Date: 16th May 2014Time: 8:00am – 2:00pmVenue: Translational Research Institute Room 2004

Research Workshop 2014

Diamantina Health Partners

Inflammation, Infection andImmunity in Digestive Disease

Hosted by Department of Gastroenterology and Hepatology PAH

Convenors:Professor Gerald Holtmann

Program Committee:Assoc Professor Linda Fletcher (Chair)Dr Brad KendallProfessor Mike McGuckinProfessor Elizabeth Powell

Co-ordinatorMs Mary-Anne Stockwell

Dear colleagues,

Digestive disorders are a spectrum of disorders affecting the alimentary canal, liver and biliary system, and pancreas. The impact of these diseases ranges from the inconvenience of a transient diarrheal disease causing missed time from work, to chronic and debilitating illnesses requiring continuous medical care, or, all too frequently, to dreaded conditions such as oesophageal, colonic or pancreatic cancer that are usually fatal. During the 20th century, dramatic changes in the incidence and prevalence of digestive diseases have occurred. For some diseases such as peptic ulcer disease, cures have been found and in the clinic we can now successfully treat these patients. This is testament to the benefits that collaboration of scientists with clinical medicine can deliver. Conversely, there are other – primarily inflammatory or infectious diseases – that have become much more prevalent and represent a considerable and growing burden to patients and society. These conditions include inflammatory bowel disorders, non-alcoholic fatty liver diseases, viral hepatitis and irritable bowel disorders. It is now well accepted that the gastrointestinal tract hosts a distinct array of microorganisms. Emerging evidence also indicates that this microbiome, and its interaction with the host, plays a critical role in many extra-intestinal diseases including rheumatic conditions, diabetes and obesity. Encompassing the overarching aim of promoting better gastrointestinal and liver health through research, the workshop will build on existing expertise and strengths, and strive to develop new approaches and partnerships, in line with the DHP theme of Inflammation, Infection and Immunity, specifically relevant to Digestive and Liver Disease. The workshop will include ‘state of the art’ overviews of current and emerging concepts presented by senior staff, as well as presentations by scientists and junior medical staff presenting their work in progress. The program will include topics such as emerging concepts of systems biology and gastrointestinal disease, the role of infections in IBD, mucosal biology in IBS and paradigm shifts for viral liver disease and non-alcoholic steatohepatitis, along with a mini update on liver cancer. The primary aim of this workshop is to bring together contributors from the Hospitals in Metro South, the TRI, the University of Queensland, the Diamantina Institute, the Mater Research Institute and other relevant stakeholders. The workshop can only provide a glimpse of the research that is happening in the field of digestive disorders; however it can provide a platform for interaction between clinicians who are directly involved in patient care and scientists who are driving the science of medical research. The opportunity to interact and build new relationships will pay dividends through improved collaboration and ultimately better outcomes for patients.

Professor Gerald Holtmann,Director, Department of Gastroenterology & HepatologyPrincess Alexandra Hospital; Associate Dean Clinical University of Queensland Faculty of Medicine & Biomedical Sciences and Faculty of Health & Behavioural Sciences

Introduction

FRIDAY 16th May 2014

Program8.00 Registration, Tea and Coffee

8.15 Opening

Professor Gerald Holtmann - Director Gastroenterology and Hepatology, Associate Dean Clinical

Faculty of Medicine and Biomedical Sciences & Faculty of Health and Behavioural Sciences

University of Queensland

Dr David Theile AO - Chairman, Diamantina Health Partners

Professor Melissa Brown - Deputy Executive Dean and Associate Dean (Research)

Faculty of Medicine and Biomedical Sciences, University of Queensland

SESSION 1: Chairs:Mark Morrison and Tim Florin

THE MICROBIOME & INFLAMMATION: INTESTINAL AND EXTRAINTESTINAL CONSEQUENCES

8.30 MINI STATE OF THE ART: The GI Microbiome - Mark Morrison

8.45 Mucosal permeability, microbiota and liver disease - Ashok Raj

8.55 Ascites and microbiota - Kevin Fagan

9.05 Microbiota diversity in ulcerative colitis - Paraic O’Cuiv

9.15 The microbiome in functional dyspepsia - Erin Shanahan

9.20 Endobarrier in obesity and metabolic diseasel - Graeme Rich

9.30 MINI STATE OF THE ART: Functional MRI - Marcus Gray

9.45 GI inflammation and central processing of afferences - Jeff Chao

10.00 Discussion

10.10 TEA

SESSION 2: Chairs: Elizabeth Powell and Carolyn McIvor

INFLAMMATION AND LIVER DISEASE

10.30 MINI STATE OF THE ART: Inflammation & The Liver - Elizabeth Powell

10.45 Rapid access model of care in HCV - Marianne Black

10.55 Therapeutic models of DILI - Iulia Onacea

11.05 Inflammatory co-factors in progressive liver injury - Terrence Tan

11.15 Population approaches to liver cancer epidemiology - Paul Clark

11.25 Update on the HCC database - Katherine Stuart

11.35 Fibroscan in viral hepatitis - Peter Hendy

11.45 Muscle mass, hepatic function and outcomes in liver transplantation - Aiden Woodward

11.55 Non-invasive predictors for decompensation in liver disease - James Thomas

12.05 Discussion

12.15 LUNCH

FRIDAY 16th May 2014

ProgramSESSION 3: Chairs: Mike McGuckin and Gerald Holtmann

INFLAMMATION AND GI DISEASE

12.45 MINI STATE OF THE ART: Gut Mucosal Inflammation - Mike McGuckin

13.00 Underpinning for a trial for a novel therapy for IBD - Tim Florin

13.10 Autophagy in IBD - Jake Begun

13.20 Novel mechanisms for IL-23-mediated pathology in colitis - Ran Wang

13.30 Muscularis propria resection in Barrett’s oesophagus - Andrew St John

13.40 Enteral nutrition in Crohn’s disease - Natalie Kiel

13.45 Beta-defensins as a novel treatment for IBD - Dan Croker

13.50 Discussion

14.00 CONCLUSION

ParticipantsPARTICIPANTS TITLE AFFILIATIONS Abstract No.

Prof Gerald Holtmann Director, Gastroenterology & HepatologyAssociate Dean (Clinical)

Gastroenterology & Hepatology, Princess Alexandra Hospital; Faculty of Medicine and Biomedical Sciences and Faculty of Health and Behavioral Sciences, University of Queensland

Dr David Theile AO Chief Executive Officer Diamantina Health Partners

Professor Melissa Brown Deputy Executive Dean & Associate Dean (Research)

Faculty of Medicine and Biomedical Sciences, University of Queensland

Professor Mark Morrison Chair & Group Leader Metagenomics

Diamantina Institute, University of Queensland

1

Professor Tim Florin Head, Inflammatory Bowel Diseases Group

Mater Research Institute, University of Queensland

15

Dr Ashok Raj PhD Scholar School of Medicine, University of Queensland; Gastroenterology & Hepatology, Princess Alexandra Hospital

2

Dr Kevin Fagan Research Fellow Gastroenterology & Hepatology, Princess Alexandra Hospital; School of Medicine, University of Queensland

3

Dr Paraic O’Cuiv Research Fellow Diamantina Institute, University of Queensland

4

Dr Erin Shanahan Postdoctoral Research Fellow

Gastroenterology & Hepatology, Princess Alexandra Hospital

5

Dr Graeme Rich Medical Registrar Gastroenterology & Hepatology, Princess Alexandra Hospital

6

Dr Marcus Gray Postdoctoral Research Fellow

University of Queensland Centre for Advanced Imaging

Dr Jeff Chao Gastroenterology and Hepatology Fellow

Gastroenterology & Hepatology, Princess Alexandra Hospital

7

Professor Elizabeth Powell Hepatologist and NHMRC Practitioner Fellow

Gastroenterology & Hepatology, Princess Alexandra Hospital; School of Medicine, University of Queensland

Dr Carolyn McIvor Director Gastroenterology & Hepatology, Logan Hospital

Gastroenterology, Logan Hospital

PARTICIPANTS TITLE AFFILIATIONS Abstract No.

Ms Marianne Black Clinical Nurse Gastroenterology and Hepatology, Princess Alexandra Hospital

8

Dr Iulia Onacea Research Officer, Inflammatory Bowel Diseases Group

Mater Research Institute, University of Queensland

9

Dr Terrence Tan Gastroenterologist & Hepatologist

Gastroenterology & Hepatology,Princess Alexandra Hospital

10

Dr Paul Clark Postdoctoral Fellow & Gastroenterologist

Gastroenterology & Hepatology, Princess Alexandra Hospital; Cancer Control Unit, Berghoffer – QIMR

11

Dr Katherine Stuart Director of Hepatology Gastroenterology & Hepatology,Princess Alexandra Hospital

Dr Peter Hendy Advanced Trainee Gastroenterology & Hepatology,Princess Alexandra Hospital

12

Dr Aiden Woodward Medical Registrar Gastroenterology & Hepatology,Princess Alexandra Hospital

13

Dr James Thomas Hepatology Fellow Gastroenterology & Hepatology,Princess Alexandra Hospital

14

Professor Michael McGuckin

NHMRC Principal Research Fellow; Deputy Director (Research)

Mater Research Institute, University of Queensland

Dr Jake Begun Gastroenterologist and Research Fellow

Mater Research Institute, University of Queensland

16

Ms Ran Wang PhD Scholar Mater Research Institute, University of Queensland

17

Dr Andrew St John Gastroenterologist Gastroenterology & Hepatology,Princess Alexandra Hospital

18

Dr Natalie Kiel Gastroenterology Fellow Gastroenterology & Hepatology,Princess Alexandra Hospital

19

Dr Daniel Croker Postdoctoral Researcher Institute for Molecular Bioscience, University of Queensland

20

Assoc Professor Linda Fletcher

Senior Scientist Gastroenterology & Hepatology, Princess Alexandra Hospital; School of Medicine, University of Queensland

Dr Brad Kendall Gastroenterologist Gastroenterology & Hepatology, Princess Alexandra Hospital; Cancer Control Unit, Berghoffer – QIMR

Ms Mary-Anne Stockwell Project Officer & Personal Assistant to Professor Holtmann

Gastroenterology & Hepatology, Princess Alexandra Hospital

STATE OF THE ART:THE GASTROINTESTINAL MICROBIOME AND HOW THE TRANSLATIONAL RESEARCH INSTITUTE CAN ENABLE AUSTRALIAN PREEMINENCE IN DIGESTIVE DISEASE RESEARCH THAT ENHANCE PATIENT OUTCOMES

Mark Morrison1,2,3, Philip Hugenholtz2,3,4,5 and Gerald Holtmann3,6

1University of Queensland Diamantina Institute; 2School of Chemistry and Molecular Biosciences and 3School of Medicine and Biomedical Sciences, University of Queensland; 4Australian Centre for Ecogenomics, University of Queensland; 5Institute for Molecular Biosciences, University of Queensland; 6Department of Gastroenterology and Hepatology, Princess Alexandra Hospital.

Australian society is recognized for its relatively high daily intake of dietary fibre, which is globally considered as being necessary for good health and well-being. However our citizens are still afflicted with some of the highest global incidence rates of gastrointestinal cancers, inflammatory bowel diseases, obesity, and related metabolic diseases. Furthermore, nearly 16% of Australians seek treatment for functional gastrointestinal disorders such as dyspepsia and irritable bowel syndrome, making these conditions among the most common reasons for medical consultations; with commensurate social and economic burdens for both patients and Australia’s health care systems. Given there are currently no cures for many of these conditions, there is a pressing need to better understand the biological drivers of their causation and recurrence, and to translate that knowledge into more effective diagnoses and treatments. In that context, the gut microbiota and its “microbiome” are now widely believed to be an extension of the host: a functional and dynamic interface of the Genotype x Environment x Lifestyle interactions that influence our health and well-being. This presentation will introduce the conceptual framework and scope of gastrointestinal microbiome studies now underway across the Translational Research Institute (TRI) and University of Queensland. The nationally unique tertiary-hospital setting that exists because of TRI offers new opportunities to better integrate microbial biology and metagenomics research with the existing basic and clinical research programs into established disease mechanisms (e.g. host genotype, mucosal and systemic immune activation, mucosal barrier function, and gastrointestinal function) to improve clinical assessments and therapeutic endpoints.

AbstractsA1

MUCOSAL PERMEABILITY, MICROBIOTA AND LIVER DISEASE

Raj A1,2, Holtmann G1,2, Bhat P1,2, Fletcher LM1,2, Tran C3, Black M1, Macdonald GA1,2

1Department of Gastroenterology and Hepatology, Princess Alexandra Hospital; 2School of Medicine, University of Queensland; 3University of Adelaide.

Background: Chronic liver disease (CLD) is a major cause of morbidity and mortality. Growing evidence suggests that gut microbiota

are implicated in CLD and one of the mechanisms could be increased intestinal permeability. Our understanding

of the role of gut microbiota in liver disease has changed significantly with the development of next generation

sequencing techniques. These factors warrant further investigation.

Aim:We are undertaking a prospective study to define the association between mucosal permeability and hepatic fibrosis

in chronic liver disease and to identify gut microbiota profiles that may be implicated.

Methods: 171 subjects have been prospectively recruited from gastroenterology and liver clinics at The Princess Alexandra

Hospital. They are divided into the following categories: chronic liver disease (CLD) of mixed aetiology; a control group

undergoing endoscopic procedures with and without mucosal disease (GI disease and GI controls respectively); and

healthy volunteers (HV). Small intestinal permeability was assessed by measuring plasma concentrations of lactulose

and rhamnose (by high performance liquid chromatography), 90 minutes after oral ingestion of 5g lactulose and 1g

rhamnose. Small intestinal permeability is expressed as a lactulose: rhamnose ratio x100 (L: R x100). Subjects were

excluded if they drank alcohol or smoked within 24 hours, had known gastro-intestinal pathology or were taking

potentially confounding medication within 4 weeks. Hepatic stiffness was measured by Transient Elastography,

giving a value in kPa that is known to correlate with fibrosis. Plasma has been collected for assessment of bacterial

translocation (limulus-amoebocyte lysate assay), and gut tissue has been collected for assessment of gut microbiota

profiles. Statistical analysis was performed using GraphPad Prism v6.0. Correlation was analysed by Spearman’s

rank test, and grouped continuous variables (presented as median values and interquartile ranges) were analysed

by Kruskal-Wallis test.

Results:We present our preliminary findings of small intestinal permeability in 87 subjects (58 with CLD, 29 HV). There is

a significant positive correlation between increasing hepatic stiffness and increasing small intestinal permeability

(r=0.25, p-value = 0.04), for a LSM below 35kPa. When these subjects are grouped into clinically relevant fibrosis

categories (no/mild fibrosis = LSM< 7.0kPa, significant fibrosis =LSM≥7.0kPa), small intestinal permeability (median,

IQR) is increased in subjects with CLD and significant fibrosis (36.8, 13.5-64.9) compared to both CLD with no/mild

fibrosis (16.0, 6.4-35.6) and HV (10.0, 5.6-30), p=0.02 (for all comparisons). Above a LSM of 35kPa, there is no

correlation (p>0.5) between hepatic stiffness and small intestinal permeability.

5. Rochester JS, Jaffe DL. Minimizing complications in endoscopic retrograde

A2

Conclusion: In subjects with chronic liver disease, our preliminary findings

demonstrate a positive correlation between hepatic fibrosis

and small intestinal permeability up until a liver stiffness of

35kPa. Above 35kPa other factors, such as portal hypertension,

may have an influence. Ongoing studies are looking at the

associated role of bacterial translocation.

A3

THE ASCITES MICROBIOME AND ITS ASSOCIATION WITH CLINICAL OUTCOMES IN PATIENTS WITH DECOMPENSATED CIRRHOSIS

Kevin Fagan1,2, Katharine Irvine2, Michelle Melino2, Geraint Rogers3, Peter O’Rourke4, Emma Ballard4, Elizabeth Powell1,2.

1Department of Gastroenterology and Hepatology, Princess Alexandra Hospital, Brisbane; 2Centre for Liver Disease Research, School of Medicine, The University of Queensland, Translational Research Institute, Brisbane; 3South Australian Health and Medical Research Institute, Adelaide, 4Statistics Unit, QIMR Berghofer Medical Research Institute, Brisbane, Australia.

Background & Aims: Ascites is the most frequent complication of cirrhosis. It is associated with increased use of hospital services, reduced quality of life and poor prognosis. Spontaneous bacterial peritonitis (SBP), a life threatening complication of ascites is associated with 50-70% mortality at 1 year. Less than 40% of SBP cases are culture positive, requiring initiation of empirical antibiotic treatment without identification of infective agents. Earlier identification of patients with poor outcomes will enable more intensive management and may improve prognosis. The application of next generation sequencing techniques to the ascites microbiome will provide novel insights into the impact of ascites bacterial load and composition on clinical parameters and outcomes. The main aim of this study is to investigate the relationship between ascites microbial species and clinical outcomes. The second aim is to investigate how ascitic fluid innate immune function and systemic inflammation affect susceptibility to infection.

Methods: For this pilot study 26 patients with cirrhosis and ascites requiring paracentesis were recruited from the Princess Alexandra Hospital. Clinical data were collected at presentation and after 6 months. DNA was extracted from the ascites cell pellet using the QIAamp DNA Mini kit (Qiagen). The bacterial 16S rRNA gene was amplified using quantitative PCR and sequenced to confirm and quantify the presence of bacterial DNA.

Results: Bacterial 16S rRNA was detected in 22/26 patients, although none had SBP at the time of recruitment. Sequencing the 16S rRNA product from ascites DNA by Sanger sequencing positively identified enteric bacteria and suggested the presence of a polymicrobial community for 5 patients. During 6 month follow up 2 patients developed SBP, 3 patients received a liver transplant and 8 died.

Future Directions: 16S gene sequencing by 454 pyrosequencing to characterise the diversity of the ascites microbiome has been completed and data analysis is underway. Ascites leukocytes, peripheral blood and serum have also been collected and stored for further investigations.

MICROBIOTA DIVERSITY IN ULCERATIVE COLITIS

Páraic Ó Cuív1,2,3*, Stanislas Mondot2,3, Eline S. Klaassens2,3, Tomas de Wouters4,5, Elisabeth Toll2,3, Wendy J. Smith2,3, Hervé Blottière4,5 and Mark Morrison1,2,3,6.

1The University of Queensland Diamantina Institute, Queensland, Australia; 2CSIRO Preventative Health Flagship Research Program, Queensland, Australia; 3CSIRO Animal, Food and Health Sciences, Queensland, Australia; 4INRA, UMR1319, Jouy-en-Josas, France; 5AgroParisTech, UMR Micalis, Jouy-en-Josas, France;6The Ohio State University, Ohio, USA.

Background & Aim: Ulcerative colitis (UC) is underpinned by at least 133 individual host genetic susceptibility loci however it is now widely accepted that these susceptibilities are necessary but not sufficient for disease to develop and that select bacteria from the microbial community resident in the gut initiate and sustain the UC inflammatory response. While the identity of the bacteria that influence disease risk in genetically susceptible individuals remains largely unknown several commensal gut bacteria, including bacteria affiliated with Bacteroides vulgatus, have been identified as potential drivers of colitis in humans and animal models. B. vulgatus is characterised by important intraspecies variations and a key aim of our research has been to evaluate the functional capacity of B. vulgatus, and determine its relevance to UC.Methods: We isolated and sequenced a new strain, termed B. vulgatus PC510, from a healthy Australian subject. Then the pan-genome of B. vulgatus was examined by comparative analysis with the type strain B. vulgatus ATCC8482 and other sequenced isolates. Next we used an in vitro model of the human gut to assess the growth and functional response of B. vulgatus when grown under healthy and UC like conditions. Finally, we used a functional cell culture assay system to determine the immunomodulatory potential of B. vulgatus PC510 and the type strain B. vulgatus ATCC8482.Results: B. vulgatus possess an extensive pan-genome that encodes putative functionalities with relevance to colonisation and persistence. Indeed a comparative genomics analysis of B. vulgatus ATCC 8482 and PC510 revealed that as much as 10% of the genes in the respective genomes are strain specific. Next, we identified 832 genes that were differentially expressed between the healthy and UC like conditions. In particular growth under UC like conditions was characterised by the expression of genes maximising energy production and conversion and the detoxification of reactive oxygen species. In contrast genes underpinning inorganic ion transport and complex carbohydrate utilisation were significantly down regulated under UC like conditions. We also determined that B. vulgatus PC510 and ATCC8482 possess a putative lipoprotein and efflux transport system previously implicated in NF-κB modulation and consistent with this both strains possessed NF-κB modulatory activity.Discussion & Conclusion: B. vulgatus is one of the most abundant bacteria in the human gut where it is considered to be a pathobiont - a symbiont that is capable of causing pathology under specific host genetic or environmental conditions. Our analyses revealed that B. vulgatus possesses an extensive pan-genome that may provide the gene repertoire and functional versatility necessary to persist in the healthy and UC gut. Our study also revealed that B. vulgatus readily adapts to growth under healthy or UC like conditions and that immunomodulatory activity is characterised by intraspecies variations.

A4

THE MICROBIOME IN FUNCTIONAL DYSPEPSIA

Erin Shanahan1, Mark Morrison2,3, Gerald Holtmann1,3

1 Department of Gastroenterology & Hepatology, Princess Alexandra Hospital2 Diamantina Institute, University of Queensland3 Faculty of Medicine & Biomedical Sciences, University of Queensland

Functional dyspepsia (FD) is a common functional gastrointestinal disorder associated with symptoms of the upper abdomen, including chronic or relapsing pain, post-prandial fullness and early satiation. These symptoms can be severe, significantly affecting quality of life. In a large proportion of patients with severe manifestations, psychiatric co-morbidities also exist. Both mucosal and systemic immune activation has been observed in FD patients, including increases in small bowel homing T lymphocytes, and augmented production of pro-inflammatory cytokines. It is also evident that an association between gastrointestinal inflammation, increased mucosal permeability and symptom manifestation exists in FD. However the cause and effect relationships between these factors are yet to be elucidated. The mucosal microbiome is likely to be a significant factor in FD, based on its role in other functional and inflammatory gastrointestinal disorders. However, to date there have been no studies of the gastric and duodenal microbiome in FD, and the microbiota inhabiting the mucosa of these regions remains poorly characterised compared to that of the large bowel.This project will investigate the microbiome of the upper gastrointestinal tract, and the potential role of the microbiome in immune activation in FD. Community profiling will be undertaken on gastric and duodenal biopsies from FD patients and controls, allowing the bacterial diversity present in the mucosa to be compared. In parallel, patients will be assessed for symptoms, gastric emptying and mucosal permeability. Indicators of immune activation and inflammation, such as pro-inflammatory cytokines, gut homing T lymphocyte (CD4+α4β7+CCR9+) numbers and eosinophil/mast cell infiltration of the mucosa will also be assessed. These gut function and immune markers will be correlated to microbiome profiles, allowing links between alterations to the microbiome and manifestations of FD to be identified. In addition, metagenomic and transcriptomic analyses will be used to identify specific components of the microbiome with the potential to modulate or specifically interact with the host immune system. An increased understanding of the gastro-duodenal microbiota, and the gastrointestinal changes that lead to FD, will enable future development of biomarkers and treatments for this disorder.

A5

A6

THE EFFECT OF TWO ENDOSCOPIC BARIATRIC TREATMENTS ON THE METABOLIC SYNDROME

Graeme Rich1,2, Gerald Holtmann1,2, Saurabh Gupta1,2, Linda Fletcher1,2, Trish O’Moore-Sullivan2,3

1 Department of Gastroenterology & Hepatology, Princess Alexandra Hospital2 School of Medicine. University of Queensland,3 Department of Endocrinology, Princess Alexandra Hospital.

Background:Obesity is a global epidemic that standard conservative measures of diet, exercise and pharmacotherapy have had limited long term success in treating. Almost 1 in 3 Australians are now obese, with that rate predicted to increase. This has numerous adverse health consequences on an individual and population level. This includes the morbidity and mortality associated with obesity related diseases such as type 2 diabetes mellitus and the other components of the metabolic syndrome. Bariatric surgical interventions are well established and effective for both weight loss and glycaemic control but have the disadvantages of requiring invasive abdominal surgery and an inability to be reversed.Several novel TGA-approved endoscopically placed bariatric devices that can be placed under conscious sedation are available. These are minimally invasive, have an excellent safety profile, and are removed endoscopically after either 6 or 12 months. This study looks to assess the effect of two of these devices when combined with a multidisciplinary strategy for weight management on a variety of biological and psychosocial parameters.

Aim: To gain further understanding of the impact and mechanism of two Endoluminal Bariatric Interventions (Endoscopic duodenal-jejunal bypass liner “Endobarrier” and Intragastric Balloon Device “Orbera”).

Method: This study will be a randomised controlled double-blinded three armed study. 90 patients will be recruited for this study. Following recruitment, the patients will be randomised to have implanted either an Endobarrier Device, an Orbera Balloon Device, or undergo an upper endoscopy without device insertion in a ratio of 1:1:1. The devices will be endoscopically placed by a single endoscopist not involved in the ongoing assessment and follow up of the study cohort other than device removal. The patients will be blinded to their treatment group as will all staff involved in the ongoing assessment of the patient throughout the follow up period. All patients will undergo the same investigations, allied health input and follow up. Patients will be followed up for two years after device insertion.

Results: Testing over this 2 year period will assess for change in the following areas: Anthropometric measurements, quality of life and self-image, functional cardiopulmonary exercise tolerance, body composition, insulin resistance and Type II diabetes control, exocrine pancreatic function, the gut microbiome, inflammation and fibrosis associated with non-alcoholic fatty liver disease and non-alcoholic steatohepatitis , nutrition and micronutrient absorption.

THE EFFECT OF SYSTEMIC IMMUNE ACTIVATION OF GASTROINTESTINAL TRACT ON CENTRAL COGNITIVE PROCESSING OF VICERO-SENSORY STIMULI, INTEROCEPTIVE SIGNALLING AND EMOTIVE EFFERENCES

Che yung Chao1, Marcus Gray2 and Gerald Holtmann1,3.

1Department of Gastroenterology and Hepatology, Princess Alexandra Hospital, Brisbane, Australia, 2Centre for Advanced Imaging, Gehrmann Laboratory, University of Queensland, Brisbane, Australia, 3Faculty of Health Sciences, University of Queensland, Brisbane, Australia

Background & Aims: Complex bi-directional gut – brain axis often plays an important role in the development of gastrointestinal disorders. Immune activation of the GI tract has been shown to be associated with symptom manifestation in patients with functional GI disorders. Altered sensory perception has also been demonstrated in inflammatory bowel disease. Current studies indicate that peripheral inflammation may influence interoceptive signalling and modulate interaction with higher cognitive affective processing. Recent rapid advances in neuroimaging including functional magnetic resonance imaging (fMRI) provide promising non-invasive methods to test hypotheses involving neural activity and modulation. This study aims to investigate the effect of changes in GI tract immune activity on cognitive processing of visceral and affective stimuli and interoceptive signalling.

Methods: 18 patients with Crohn’s disease on maintenance therapy with infliximab or adalimumab will be recruited from a tertiary hospital IBD clinic. Baseline characteristics along with biochemical, radiological and endoscopic disease activity assessments will be collected. Detailed psychological assessment using validated questionnaires will also be performed. A 3-teslar magnetic resonance imaging of the brain will be performed to acquire functional measures of neural activity during three validated experimental tasks designed to assess representation of visceral state, interoceptive signalling and cognitive processing of affective efferences. Function MRI testing will be undertaken prior and after patients’ anti-TNF alpha therapy to assess the changes in neural activity in relation to alterations in GI tract immune activity with biologic therapy.

A7

RAAT- Rapid Assessment and Access to Treatment – an innovative model of care for patients with Hepatitis C within the hospital outpatients setting

Marrianne Black1, Cheryl Sendall1, Caroline Tallis1, Rebecca Ryan1, Katherine Stuart1 and Gerald Holtmann1,2.

1 Department of Gastroenterology and Hepatology, 2 School of Medicine University of Queensland.

Untreated hepatitis C within Australia will potentially create a significant increase in the number of patients developing decompensated liver disease and hepatocellular carcinoma. This will place a huge burden on society and the health system. The waiting times for assessment for patients referred with liver disease had expanded due to demand for services surpassing availability within our department. A clinical audit of the Category 3 waiting list highlighted the need for an innovative approach to the assessment and management of long wait patients potentially suitable for treatment of their liver disease.

A clinical audit of 890 charts was undertaken to identify the indications for referral to the liver clinics. The findings included 50 patients with hepatitis B, 523 patients with hepatitis C, and 301 patients considered suitable to remain on the waiting list at the time. The RAAT model of care was then implemented. This would include an assessment by a consultant hepatologist in the outpatient setting, a FibroScan® (transient elastography) and laboratory and radiological tests ordered at initial consultation. The patients were also reviewed by a specialist hepatology treatment nurse for suitability and initial education regarding treatment. 54 patients have commenced treatment with a RVR (rapid viral response rate) of approximately 90 percent.

This innovative model of care has seen an increased throughput and initiation of treatment for eligible patients, with reduced waiting times, hospital visits and delays to treatment commencement.

A8

THERAPEUTIC MODELS OF DRUG INDUCED LIVER INJURY

Iulia Oancea1, Valerie Barbier1, David Chee1, Ran Wang1, Martina Proctor1, Ingrid Winkler1, Tim Florin1,2

1Mater Research Institute, University of Queensland; 2Department of Medicine University of Queensland

Background & Aim: Paracetamol is involved in a large proportion of accidental paediatric exposures and suicidal attempt cases and remains the most important single cause of acute fulminant hepatic failure in Western countries. It has a poor prognosis, with acute hepatic failure followed by indication for transplantation. SOS (sinusoidal obstructive syndrome), a hepatic vascular complication of chemotherapies and Stem Cell transplant, has been described in up to 50% of cases of allogeneic transplants and up to 30% after TG (thioguanine) administration and is associated with high mortality. A more effective therapy for prevention of SOS and paracetamol induced liver injuries would be clinically valuable. Both paracetamol and TG induced liver toxicities have an increased inflammatory infiltrate (neutrophils and macrophages) in the parenchyma that initiates or exacerbates the injury. We hypothesise that blocking the recruitment of inflammatory cells will alleviate these drug induced liver injuries (DILI).

Methods: 1. C57Bl/6 wildtype (WT) and E-selectin-/- 8-10 week-old mice were gavaged daily with 100µL of vehicle control or TG for up to 12 days. 2. Paracetamol was administered once to 5 week-old WT mice after 15h fasting and mice were sacrificed at different time points. Histological analysis, markers of inflammation, hepatocellular and endothelial injury were assessed in both models.

Results: Both TG and paracetamol caused liver injury in WT mice. Besides the hepatocellular injury, E-selectin, a marker of leukocytes homing present on the surface of endothelial cells (EC), had an early marked upregulation in both DILIs . TG induced SOS was abrogated in E-selectin-/- (p<0.05). In paracetamol induced DILI, co-administration of an E-selectin blocking agent reduced the hepatocellular injury measured by area of necrosis and transaminase levels (p<0.05).

Discussion & Conclusion: Both TG and paracetamol affect directly and indirectly endothelial cells in vivo with activation and upregulation of E-selectin, followed by infiltration of inflammatory cells that amplify or initiate liver injury. When E-selectin is either absent or blocked the liver injury is minimised emphasising the importance of EC activation in the recruitment of a damaging inflammatory infiltrate, even though the mechanisms of the initial injury are quite different.

A9

ETHANOL AND A HIGH-FAT DIET INDUCES INTESTINAL ENDOPLASMIC RETICULUM STRESS

TCH Tan1,3, DHG Crawford1, LA Jaskowski1, GJ Anderson2, VN Subramaniam2, LM Fletcher1,3

1 School of Medicine, University of Queensland, Brisbane, Australia2 Queensland Institute of Medical Research, Brisbane, Australia3 Department of Gastroenterology and Hepatology, Princess Alexandra Hospital, Brisbane, Australia

Introduction: Endoplasmic reticulum (ER) stress has been implicated in the development of liver and intestinal inflammation. Alcohol and a high-fat diet (HFD) are known to induce hepatic ER stress but the effects of these two factors on the intestine remain unclear.

Materials and Methods: We investigated the possibility of intestinal ER stress as a potential factor in a mouse model of alcohol and HFD-induced liver injury. 8-week old male C57/BL6 mice were fed ad libitum ethanol, a HFD or in combination.

Results: Combination ethanol and HFD led to moderate steatohepatitis but ethanol or HFD alone led to mild-moderate steatosis only with minimal liver injury. Ethanol and/or a HFD induced phosphorylation of IRE-1α and splicing of XBP-1 in the small intestine, with increased activation of intestinal EIF-2α and ERK1/2 with a corresponding increase in protein levels of JNK. Ethanol but not HFD led to siginifcant increases in NF-κB protein levels, a downstream effect of ER stress. Both ethanol and HFD also significantly reduced mRNA levels of intestinal tight junction proteins ZO-1 and TJAP-1 but an increase in Symplekin, indicating a possible increase in intestinal permeability.

Conclusion: Alcohol and HFD can induce intestinal ER stress, possibly increasing gut permeability and this may be an additional mechanism for liver injury in alcohol and non-alcoholic fatty liver disease.

A10

HEPATOCELLULAR CARCINOMA EPIDEMIOLOGY IN QUEENSLAND, 1996-2010

Paul J. Clark 1,2,3, Peter Baade4, Katherine Stuart3, Darrell Crawford2, Graeme MacDonald3, Barbara Leggett5, David Whiteman1

1Cancer Control Unit, Berghofer-QIMR Medical Research Institute, 2School of Medicine, University of Queensland, 3Gastroenterology and Hepatology, Princess Alexandra Hospital, 4Epidemiology, Cancer Council Queensland, , 5Gastroenterology, Royal Brisbane and Women’s Hospital.

Introduction: Hepatocellular carcinoma (HCC) burden is increasing globally, but epidemiologically informed data are required to ensure services are targeted to those groups who are most at risk of disease or of poor survival once diagnosed. Using population- based data, we documented the incidence and survival of HCC in Queensland, Australia. Queensland occupies a land mass of 1,730,648 km² - larger than the combined area of France, Germany, Italy and Spain, and much of it is remote. Half of Queensland’s4.5 million population live in regional or remote locations, distant from southeast corner of the state where the state’s capital city is located.

Methods: In Queensland, notification of cancer diagnoses with the state Cancer Registry has been mandatory since 1982. HCC incidence between 1996 and 2010 was analysed for gender- and age-standardized incidence, ethnicity, Indigenous status, remoteness (Accessibility/Remoteness Index of Australia), and socio-economic status (Index of Relative Socio-Economic Disadvantage) and assessed with multivariable regression (MVR). Log rank test assessed Kaplan Meir survival curves. MVR Cox regression evaluated potential determinants of survival, adjusting for era of diagnosis, gender, age, birth country of English vs non-English speaking origin, social disadvantage and remoteness.

Results: There were 1461 liver cancer notifications between 1996-2010. 81% of cases were male with an average age of 65. 4.5% of cases were in Indigenous Australians, who represent less than 3.5% of the population. 26-32% were immigrants from non-English speaking countries.Incidence of HCC in males was greater than females (ASR=4.53, 95% CI=4.3-4.8), however for both genders, incidence increased over time (males, 3.5% per year (95%CI=2.3-4.8, p<0.001) and females 3.1% (0.5-5.7, p<0.017). Male gender, age greater than 60 years, residing in a major city and more socio-economic disadvantage were associated with higher HCC incidence on MVR. Median survival improved over time but remains poor (1996-2000, 152 days (SE 17.7 days); 2000-2005, 212 days (SE 31.6 days); 2005-2010, 303 days (SE 28.1 days, P <0.001). On MVR, poorer survival was associated with age, earlier era of diagnosis, and more social disadvantage. Non-English-speaking background had a positive association with survival possibly reflecting a higher proportion of non-cirrhotic, HBV-associated HCC in non-English speaking immigrants. After adjustment for remoteness and social disadvantage, there was no significant disparity in survival for Indigenous Queenslanders (Median survival Indigenous vs. non- Indigenous, 239 vs 304 days P=0.364).

Conclusion: HCC incidence has increased in Queensland. Survival has improved but remains poor. Incidence and survival disparities exist for individuals who are older and socially disadvantaged. Targeted outreach programs in these population groups should include patient and family doctor education to improve diagnosis, cancer surveillance, and referral for treatment of liver disease risk factors such as viral hepatitis.

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CHANGING PRACTICE: ANALYSIS OF THE IMPACT OF TRANSIENT ELASTOGRAPHY IN A VIRAL HEPATOLOGY OUTPATIENT CLINIC. DHP RESEARCH WORKSHOP, BRISBANE 2014.

Peter Hendy1,2, Sara Davidson1, Burglind Liddle1, Mazhar Haque1,2.

1 Department of Gastroenterology and Hepatology, Mater Adult Hospital 2School of Medicine, University of Queensland

Background & Aim: Liver stiffness measurement using transient elastography (FibroScan®) is a well validated non-invasive tool increasingly used to assess hepatic fibrosis. Anecdotally, this has reduced the requirement for liver biopsy and improved capacity in hepatology outpatients. This in progress, retrospective study seeks to examine the impact of the introduction of transient elastography on a hospital based outpatient hepatology clinic.

Methods: Historical outpatient attendance and patient records are to be examined for a two year period prior to, as well as the one year period post the introduction of transient elastography at the Mater Adult Hospital. Occasions of service and number of liver biopsies will be compared between the periods, in addition to the indication for liver biopsy. For new hepatitis B patients, the time to treatment plan is to be compared over the respective time periods.

Results and Conclusion: Study currently in progress

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ASSESSMENT OF MUSCLE MASS, HEPATIC FUNCTION AND OUTCOMES IN PATIENTS AWAITING LIVER TRANSPLANTATION

Aidan Woodward1, Jeff Coombes2, Graeme Macdonald1

1Department of Gastroenterology, Princess Alexandra Hospital; 2School of Human Movement Studies, University of Queensland

BACKGROUND & AIM: One of the cardinal features of advanced liver disease is a poor nutritional state with a catabolic metabolism and muscle wasting. Malnutrition affects approximately 50-100% of patients with decompensated cirrhosis and at least 20% of patients with compensated cirrhosis. Malnutrition is associated with an increase in adverse outcomes in cirrhotic patients. The pathogenesis of malnutrition in liver disease is multifactorial with lipid, carbohydrate and protein metabolism all affected. However there is a predominant loss of muscle mass (sarcopenia). The aims of this project are to examine in adult patients awaiting liver transplantation: a) Non-invasive measures of muscle mass, muscle function and liver function, and b) The relationship between these and outcomes in this population

METHODS: We aim to prospectively recruit 50 adult patients with chronic liver disease accepted on the liver transplant waiting list at the Princess Alexandra Hospital. We will use this group to establish baseline body composition data pre-transplant. We will then look at extending this project into the peri-transplant and post-transplant period in the following years.Baseline data will be collected from investigations which are required as standard pre-transplant assessment. This would include demographic, biochemical and radiological results. All patients will undergo a nutritional review and collection of anthropometric data including height, weight, waist circumference, mid arm muscle circumference, and skin fold thickness. Assessment of muscle function will be performed with handgrip strength, Sit-to-Stand Test, and gait speed. Body composition will be assessed using: total body potassium counting, total body water, extracellular water, DEXA and BIA. CT of the liver is routinely performed pre transplant and will be reanalysed by the investigators to measure the cross-sectional muscle area at the L3/L4 level.Hepatic function will be evaluated using the 13C-Methacetin breath test and ICG retention test.

DISCUSSION: Our research will assess multiple variables which could be used to predict morbidity or mortality of patients awaiting liver transplant. This will help enhance our ability to risk stratify patients on the liver transplant waiting list and hopefully improve outcomes.

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NON-INVASIVE PREDICTORS FOR DECOMPENSATION IN LIVER DISEASE

James Thomas1, Caroline Tallis1, Katherine Stuart1.

1 Department of Gastroenterology and Hepatology, Princess Alexandra Hospital.

Hepatocellular carcinoma (HCC) is the 5th most common cancer worldwide. The most effective treatment is liver transplantation, however this is not suitable for many patients and there is a shortage of available donor organs. HCC usually occurs on the background of cirrhosis therefore more targeted treatments risk compromising the function of the vulnerable liver (termed “decompensation”). Surgical resection and locoregional treatments such as transarterial chemoembolisation (TACE) and radiofrequency ablation (RFA) therefore require careful patient selection to minimise this. Current methods of predicting the risk of liver decompensation in this patient group are limited. No single modality in routine clinical use offers accurate risk stratification. Furthermore, methods such as hepatic venous pressure measurement and liver biopsy are also invasive thereby carrying significant risk to the patient. Since 2012, the Combined Assessment of Liver Function (CALF) service at Princess Alexandra Hospital has tested a panel of non-invasive markers of liver function in cirrhotic patients under consideration for treatment of HCC. Fibroscan, indocyanine green clearance and the 13C methacetin breath test have been measured in this cohort. Each of these is supported by data showing some value in predicting disease stage or risk of decompensation. The aim of this project is to determine the influence of these results on clinical decision making and also the relationship to the risk of post-treatment decompensation. To date 99 patients have been assessed by the CALF service. We will be assessing pre-test demographic, biometric, biochemical and clinical parameters in addition to validated scoring systems based upon these data. Patients will be categorised according to treatment modality and the predictive value of CALF components will be ascertained and compared to the routine clinical tools.

IN CONFIDENCE

THE UNDERPINNINGS FOR A TRIAL OF A NOVEL THERAPY FOR IBD

Tim Florin1,2,3, Jake Begun1,2, Michael Shetzline4, Iulia Oancea2, John A Duley5 6, Michael Henman5 ,Siddharth Jambrunkar2, Michael A McGuckin2, Amirali Popat2,6, Paraic O’Cuiv7, Rohan Lourie5, Paul Chou8, John Wright9, Ben Phillis10

1 Department of Gastroenterology Mater Health Services, 2Mater Research Institute University of Queensland, 3Department of Medicine University of Queensland, 4Ferring International PharmaScience Center, 5Mater Pathology Service, 6PACE University of Queensland 7Diamantina Institute University of Queensland, 8Mater Radiology. 9Department of Veterinary Sciences University of Queensland, 10Uniquest

Background: IBD are polygenic chronic inflammatory diseases. Gently antagonising innate and acquired immunity is the mainstay of treatment for most IBD. An optimal treatment should be oral, fast-acting, durable, safe, palatable and economical. No current treatment fulfills all of these criteria. The most widely used oral treatments for non-trivial IBD are thiopurine drugs – azathioprine and mercaptopurine – but they are slow to work and not always safe or palatable. Current parenteral treatments are hugely expensive and not always safe or durable. Thioguanine (TG) is a thiopurine, which in its current formulation ticks off many of the criteria for an optimal treatment, but it has an off-target association with the serious adverse complication of hepatic sinusoidal obstructive syndrome (SOS), and a narrow therapeutic window where too much TG causes myelosuppression.

Aim: is to trial a formulation of TG that should avoid both SOS and myelosuppression.

Underpinnings: Data will be shown to support that – a) TG delivery which avoids high Cmax in the portal circulation, prevents SOS in a murine model; b) a formulation which releases TG over 3h, avoids high Cmax in the portal circulation of dogs; c) TG antagonises colitis within days in our murine models, and is believed to act within < 4 weeks in IBD, which is not the case for conventional thiopurines;d) splitting a therapeutic daily dose of TG (mean 0.6 mg/kg/d) appeared to be safe and effective in a cohort study of 62 patients with severe IBD over a median observation period of 10 months

Trial: Proof-of-concept (POC) trial designs targeting ulcerative colitis will be discussed. Pre-trial toxicology studies are not required because TG is a TGA-approved pharmaceutical. A properly resourced POC trial to test efficacy and safety, could and should be done in an efficient and timely manner by the Diamantina Health Partners.

IN CONFIDENCE UNIVERSITY OF QUEENSLAND

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ROLE OF AUTOPHAGY IN IBD – A FUNCTIONAL GENETIC APPROACH

Jakob Begun1,2, Kara Lassen2, Ramnik Xavier2,3.

1Mater Research Institute, University of Queensland, 2Centre for Computational and Integrative Biology, Massachusetts General Hospital, 3Department of Gastroenterology, Massachusetts General Hospital.

Background: Autophagy has been implicated in the pathogenesis of inflammatory bowel disease (IBD) through the identification of autophagy associated genes in genome-wide association studies (GWAS) including the T300A coding polymorphism in the core autophagy protein ATG16L1. Autophagy is a critical cellular process with implications for metabolism, cell signalling, programmed cell death, cancer biology, and immunology. Recently autophagy has been recognized as a critical pathway for controlling intracellular bacterial infection, and altered bacterial handling by the gut is recognized as a pathogenic finding in inflammatory bowel disease. Major gaps in knowledge exist in this process, particularly in the identification of factors that control antibacterial autophagy. We hypothesized that additional genes identified by GWAS may be contributing to antibacterial autophagy and control of intracellular bacterial replication.

Methods: A high throughput automated microscopy based antibacterial autophagy assay was developed in an epithelial cell line using the model intracellular pathogen Salmonella enterica. A total of 476 genes associated with inflammatory bowel disease GWAS loci were tested using RNAi knock-down to determine an effect in this assay. In addition these genes were tested in an intracellular bacterial replication control assay, a process that has previously been shown to rely on autophagy dependent and independent mechanisms. Preliminary genes associated with impaired function were validated and prioritized for mechanistic evaluation in vitro and in vivo.

Results: Of the 476 genes tested 35 resulted in a consistent reproducible defect in antibacterial autophagy after knock-down. The majority of these genes had not previously been implicated in autophagy, but many could be mapped onto the autophagy protein network through published protein-protein interaction databases. The majority of the genes identified showed significant expression in the colon and/or small intestine of IBD patients. Intracellular replication testing revealed that a majority of genes affecting autophagy rates also impair bacterial clearance, but also identified additional genes that contributed to control of intracellular replication through independent mechanisms.

Conclusion: Multiple genes implicated in the pathogenesis of IBD through GWAS studies were found to impact the anti-bacterial autophagy pathway and impair the control of intracellular bacterial replication. This highlights the importance of autophagy and bacterial handling to the pathogenesis of IBD and may suggest future therapeutic targets.

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NOVEL MECHANISMS FOR IL-23-MEDIATED PATHOLOGY IN COLITIS

Ran Wang1,2, Sumaira Z. Hasnain1, Hui Tong1, Rohan Lourie1, Alice C. Chen1,2, Iulia Oancea1,2, Timothy H. Florin1,2, Rajaraman Eri1,4, Michael A. McGuckin1,2 1Immunity, Infection and Inflammation Program, Mater Research Institute – The University of Queensland, TRI, 2School of Biomedical Sciences and School of Medicine, University of Queensland, 3School of Biomolecular and Physical Sciences, Griffith University, 4School of Human Life Sciences, University of Tasmania, Launceston.

Background & Aim: IL-23, comprising p40 (shared with IL-12) and p19 subunits, is a member of the IL-12 cytokine family known to promote and sustain proinflammatory TH17 responses and linked to the pathogenesis of inflammatory bowel disease (IBD). We have previously shown that blocking IL-17A, IL-17E or IL-17F cytokines, or the IL-17Ra receptor by monoclonal antibodies was not efficacious in alleviating colonic inflammation in a murine intestinal epithelial defect-induced colitis model. The aim of this study was to determine the effects of anti-IL-23 therapy and study the underline mechanisms of anti-p19 therapy in suppressing colitis.Methods: A murine spontaneous colitis model Winnie mice were used in the study. Winnie mice share similarities with human ulcerative colitis, developing progressive intestinal inflammation derived from an epithelial defect and driven by a mixed but IL-23/TH17-dominated proinflammatory response. Mice with established colitis were treated for 2 weeks with antibodies, and histology and molecular markers were assessed after treatment. Effects of IL-23 on intestinal epithelial cells were assessed by in vitro treatment of human colonic LS174T cells.Results: Two weeks treatment with anti-p19 antibody significantly ameliorated established colitis compared to Winnie mice receiving isotype antibody. Anti-p19 decreased colon weight (p<0.001) and histological colitis scores (p<0.05) and was superior to anti-p40 antibody. Although anti-p19 treatment did not dampen the proinflammatory cytokine production from mesenteric lymph node leucocytes cultured in vitro, anti-p19 diminished colonic neutrophil infiltration, suggesting that the efficacy of anti-IL-23 treatment in Winnie established colitis may be due to mechanisms other than direct suppressing cytokine-producing immune cells. Anti-p19 downregulated Mip2a chemokine mRNA expression in isolated colonic epithelial cells (p<0.05 compared to isotype control) and restored colonic goblet cell mucin production. IL-23 has previously been thought to act only on leukocytes, however, we show here that IL-23 acts directly on intestinal epithelial cells. Treatment of human colonic LS174T cells with 50 ng/ml recombinant IL-23 for 24 h increased intracellular reactive oxygen species (ROS) levels by 20-fold (p<0.001) in a Stat3 transcription factor-dependent manner. IL-23-driven ROS decreased MUC2 mucin biosynthesis (p<0.01) and secretion (p<0.001), and increased IL-8 release (p<0.001) in LS174T cells. The effect of IL-23 on IL-8 secretion was completely blocked, and the effect on MUC2 biosynthesis and secretion were partially blocked, by the ROS inhibitor, reduced glutathione. Due to these multiple mechanisms of action, neutralization of IL-23 in colitis is likely to be efficacious not only via effects on T cells and innate lymphoid cells, but by reducing chemokine-mediated recruitment of inflammatory cells into the intestine, and by replenishing intestinal mucus, thereby helping restore normal intestinal homeostasis.Discussion & Conclusion: Our results show that targeting IL-23 alone suppresses colitis. The direct adverse effects of IL-23 on epithelial cells we describe may partially underlie the protection from IBD conveyed by hypomorphic IL-23 receptor polymorphisms, and contribute to the efficacy of IL-23 neutralizing antibodies in IBD.

LOW RATE OF MUSCULARIS PROPRIA RESECTION USING PRE-INJECTION EMR FOR HIGH GRADE DYSPLASIA AND EARLY OESOPHAGEAL ADENOCARCINOMA IN BARRETT’S ESOPHAGUS: POTENTIAL IMPLICATIONS FOR POST-EMR ESOPHAGEAL STRICTURE

Andrew St John1, Neal Walker2, 3, Luke F. Hourigan1

1Department of Gastroenterology and Hepatology Princess Alexandra Hospital, 2School of Medicine University of Queensland, 3Envoi Specialist Pathologists, Brisbane.

Background and Aim:Endoscopic mucosal resection (EMR) is an established technique for the diagnosis and treatment of high-grade dysplasia (HGD) and early esophageal adenocarcinoma (EAC) in Barrett’s esophagus (BE). Abrams et al assessed specimen depth in EMR specimens using two different EMR techniques (with and without pre-injection).1 Mean specimen depth was 5 mm with muscularis propria (MP) identified in 50-65%.. Pre-injection specimens had a lower rate of MP resection (50% versus 65%, p=0.52) and a lower post-EMR oesophageal stricture rate (15.4% versus 33.3%, p=0.24). We retrospectively assessed specimen size and depth of resection for EMR specimens using a modified pre-injection technique.

Methods:All cases of EMR of lesions in the distal esophagus on adult patients with BE between September 2012 and October 2013 were identified retrospectively. Only cases of focal EMR (≤2 resections) were included in the analysis. All EMR procedures were performed by a single experienced endoscopist using the Olympus 1T therapeutic gastroscope (Olympus America, Center Valley, PA) and the 7 Fr Duette EMR device (Wilson-Cook, Bloomington, IN). Submucosal pre-injection of 2-4 mL of normal saline, indigo carmine with dilute adrenaline (1:40,000) was performed to elevate the lesion prior to EMR in all cases. The lesion was suctioned and banded then resected using snare electrocautery below the band. All specimens were reviewed by an expert GI pathologist.

Results:19 consecutive EMR procedures were performed on 16 patients between September 2012 and October 2013. 15 of the 16 (94%) patients were male, and the median patient age was 68 years (range, 58-76). 3 patients required two sessions of EMR during the study period. EAC was identified in 11 specimens from 10 patients (63%). HGD was identified in the remaining specimens. Median specimen size was 14.0 x 11.0 x 3.0 mm. For the 11 cases of EAC, the median lesion size was 6.0 mm wide x 1.5 mm deep with only 2 cases showing invasion into the submucosa (T1b). No cases of vascular or perineural invasion were identified. Deep resection margins were clear of adenocarcinoma in all cases (median deep clearance margin 1.5 mm, range 0.6-4.0). MP was identified at the base of only one specimen (5%). There were no cases of perforation.

Conclusion:Pre-injection EMR using the Duette system provides adequate specimen size for diagnosis and staging with a very low rate of MP resection. This novel finding may help to explain the variable rates of post-EMR oesophageal stricture using different EMR techniques in the published literature. Furthermore, EMR resection depth and presence of MP may be significant factors in predicting post-EMR stricture rate.

References:1. Abrams JA, Fedi P, Vakiani E, et al. Depth of resection using two different endoscopic mucosal resection techniques. Endoscopy 2008;40:395-399.

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ENTERAL NUTRITION IN CROHN’S DISEASE

Natalie Kiel1, Siong Pang2, Neal Martin1

1Dept of Gastroenterology and Hepatology and 2Department of Nutrition and Dietetics, Princess Alexandra Hospital

Background and AimsExclusive enteral nutrition has long been established as an effective therapy for active Crohn’s disease, in both treatment naïve and treatment experienced patients. It is particularly favoured in children as an alternative to steroid therapy, therefore avoiding the negative impacts of steroids on growth. Use in adult patients has traditionally been much more infrequent, typically due to poor tolerance of the enteral nutrition formulas used. Here we investigate the efficacy of enteral nutrition in inducing clinical and biochemical remission in all-comers with active Crohn’s disease in our real-life patient cohort.

MethodsWe will review the clinical and biochemical data from all patients with Crohn’s disease treated with exclusive enteral nutrition between Jan 2012 and March 2014 at Princess Alexandra Hospital. Active Crohn’s disease is defined as presence of diarrhoea (>3 loose stools/day), weight loss of >2kg in the past month, elevated fecal calprotectin, or CRP >10. Response to treatment will be evaluated from both clinical assessment and a reduction in inflammatory markers (either CRP or fecal calprotectin).

ResultsResults to follow.

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BETA-DEFENSINS AS A NOVEL TREATMENT FOR IBD

Daniel E. Croker1, Rink-Jan Lohmann1, Daniel Burger3, Phil Hugenholtz1,2, Gerald Holtmann3,4, and Matthew A. Cooper1.

1Institute for Molecular Bioscience, The University of Queensland, 2 Australian Centre for Ecogenomics, School of Chemistry and Molecular Bioscience, The University of Queensland, 3Department of Gastroenterology and Hepatology, Princess Alexandra Hospital, 4Faculty of Medicine and Biomedical Sciences, The University of Queensland, Brisbane, Australia.

Background & Aim: β-defensins are natural antimicrobial peptides expressed at a number of epithelial surfaces. Human β-defensin 2 (hBD2) expression is induced in response to inflammatory stimuli and entero-invasive bacteria with little expression by the epithelium in the normal colon. hBD2 has been shown to be induced to significantly higher levels in irritable bowel disease (IBD) patients compared to controls with significantly greater up-regulation in ulcerative colitis (UC) than in Crohn’s disease (CD). hBD2 has shown weak antimicrobial activity in limited testing to date while also showing immunomodulatory effects on peripheral blood mononuclear cells (PBMC). There is currently the theory that microbiome dysbiosis pay a significant role in the pathology and disease progression of IBD. Here we plan to further investigate the utility of hBD2 as a treatment for IBD. hBD2 will be tested for the ability to ameliorate disease symptoms in a mouse model of colitis whilst also profiling gut microbiota in both the mouse colitis model and clinical tissue biopsies from control and IBD patients. Methods: The anti-bacterial activity of hBD2 will be quantified against key protective and pathogenic human gut bacterial flora. The immunomodulatory effects of hBD2 will be quantified in cells of the innate immune system of both mouse and human origin. The dextran sodium sulphate (DSS) model of colitis in mice will be established and the utility of hBD2 as a treatment will be tested in an acute 10-day prophylactic model. hBD2 will be given in a once a day oral dose and will be monitored for the ability to maintain homeostasis and/or ameliorating dysbiosis in a murine DSS IBD model, with concomitant profiling of the gut microbiota by metagenomic sequencing. Profiling of microbiota will also be performed in human tissue biopsies from control and diseased patient samples using a variety of sampling techniques. Expression of hBD2 will be quantified by immune-histology in both mouse DSS colitis and human tissue biopsies.

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