A29 HIGH DIMENSIONAL SINGLE CELL ANALYSIS OF IL-4 TREATED MACROPHAGES REVEALS A HETEROGENIC PHENOTYPE AND THE ABSENCE OF CD206+ SUBSETS IN CROHN'S DISEASE PATIENTS

Background

Individuals with IBD have a reduced quality of life and while treatment has improved, a cure remains elusive. Interleukin-4 differentiated macrophages (M(IL4)s) from healthy donors and IBD patients in remission promote epithelial wound repair and reduce the severity of colitis in a mouse model: findings that support the autologous transfer of M(IL4)s to treat IBD. However, issues remain if this novel therapy is to advance to clinical evaluation: a much greater understanding of the possible heterogeneity within the human M(IL4) population, the biology of any sub-groups therein and the biology of any M(IL4) subtypes is needed.

Purpose

To determine if cryopreservation, sex, and disease status in Crohn's disease (CD) impact the phenotype and function of M(IL4)

Method

Blood mononuclear cells were collected from healthy donors, and individuals with active CD or in remission (n=6/group), and differentiated to macrophages with GMP-grade recombinant human M-CSF (10 ng/ml, 7 days). Macrophages (2.5 x10⁵) were activated with IL-4 (10ng/ml, 48h). Fresh and cryopreserved M(0) and M(IL4) were stained using a panel of 18 metal-conjugated antibodies. Data were acquired on a Helios CyTOFII mass cytometer. FCS files were imported into Cytobank for manual gating (viable CD45⁺CD3^-CD19^- singlet cell events) and exported for meta-clustering in R with the CATALYST package using the FlowSOM function with 10 metaclusters.

Result(s)

FlowSOM analysis on M(IL4) from healthy donors indicated clear differences between M(0) and M(IL4), with 8 metaclusters >1.5% of M(IL4)s: the most abundant metaclusters express high and intermediate CD206, PDL1, CD11b, CD33, CD64, HLA-DR and low CD14 levels. There were no significant differences in these M(IL4)s metaclusters between males and females, or fresh vs. cryopreserved cells using this characterization strategy. M(IL4) from patients with active CD, were markedly different with the absence of three high-intermediate CD206⁺PDL1⁺ metaclusters and a general lack of CD206⁺ metaclusters compared to healthy controls. Surprisingly, and despite M(IL4)s from CD patients in remission showing increased CD206 mRNA, CYTOF analysis revealed that the macrophages were more similar to those from individuals with active disease than those from healthy controls

Conclusion(s)

Here human macrophages activated with IL4 in vitro are revealed as a heterogeneous population, and subsets characterized by increased high CD206 expression are generally absent in active Crohn’s disease. Intriguing while prior experiments with M(IL4) from CD patients in remission reduced the severity of colitis in rag1^-/- mice, the characterization of these cells via 18 protein markers indicates they are more like M(IL4)s from patients with active disease compared to healthy controls. While presenting autologous M(IL4) transfer as a novel approach for IBD, a much fuller understanding of the phenotype and function of M(IL4)s (and sub-populations therein) is required before this would become a therapeutic option

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Disclosure of Interest

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Integrated versus nOn-integrated Peripheral inTravenous catheter. Which Is the most effective systeM for peripheral intravenoUs catheter Management? (The OPTIMUM study): a randomised controlled trial protocol

INTRODUCTION

Peripheral intravenous catheters (PIVCs) are frequently used in hospitals. However, PIVC complications are common, with failures leading to treatment delays, additional procedures, patient pain and discomfort, increased clinician workload and substantially increased healthcare costs. Recent evidence suggests integrated PIVC systems may be more effective than traditional non-integrated PIVC systems in reducing phlebitis, infiltration and costs and increasing functional dwell time. The study aim is to determine the efficacy, cost-utility and acceptability to patients and professionals of an integrated PIVC system compared with a non-integrated PIVC system.

METHODS AND ANALYSIS

Two-arm, multicentre, randomised controlled superiority trial of integrated versus non-integrated PIVC systems to compare effectiveness on clinical and economic outcomes. Recruitment of 1560 patients over 2 years, with randomisation by a centralised service ensuring allocation concealment. Primary outcomes: catheter failure (composite endpoint) for reasons of: occlusion, infiltration/extravasation, phlebitis/thrombophlebitis, dislodgement, localised or catheter-associated bloodstream infections.

SECONDARY OUTCOMES

first time insertion success, types of PIVC failure, device colonisation, insertion pain, functional dwell time, adverse events, mortality, cost-utility and consumer acceptability. One PIVC per patient will be included, with intention-to-treat analysis. Baseline group comparisons will be made for potentially clinically important confounders. The proportional hazards assumption will be checked, and Cox regression will test the effect of group, patient, device and clinical variables on failure. An as-treated analysis will assess the effect of protocol violations. Kaplan-Meier survival curves with log-rank tests will compare failure by group over time. Secondary endpoints will be compared between groups using parametric/non-parametric techniques.

ETHICS AND DISSEMINATION

Ethical approval from the Royal Brisbane and Women's Hospital Human Research Ethics Committee (HREC/16/QRBW/527), Griffith University Human Research Ethics Committee (Ref No. 2017/002) and the South Metropolitan Health Services Human Research Ethics Committee (Ref No. 2016-239). Results will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ACTRN12617000089336.

Strength in unity: the power of redesign to align the hospital team

OBJECTIVE

The aim of Queen Elizabeth II Jubilee Hospital (QEII) redesign project (QEII United) was to enhance timely access to an inpatient bed and maximise opportunities to value add during the inpatient episode of care.

METHODS

A tripartite relationship between the hospital team, system manager and external consultants. The team, QEII United, was formed to 'diagnose, solve and implement' change under the unifying metaphorical banner of a football team. A marketing strategy and communication plan targeted the key 'players' and outlined the 'game plan'. Baseline data were collected, analysed and reported in keeping with key aims. Strategies for systems improvement implementation were attached to key performance indicators (KPIs).

RESULTS

Thematic KPIs were developed to embed internal process change to reflect the contributions made towards the National Emergency Access Target (NEAT) at each stage of the patient journey. As such, access block of under 20%, morning discharge rates of 50% before midday, reduced length of stay for selected elective orthopaedic and general medical diagnostic related groupings (DRGs; i.e. relative stay index ≤1) and hospital in the home (HITH) utilisation rates 1.5% of all admissions were all met. Key to sustainability was the transfer of clinical redesign skills to hospital staff and the fostering of emergent ground up leadership.

CONCLUSIONS

QEII United's success has been underpinned by the development of themed solution areas developed by the hospital staff themselves. Robust baseline data analysis used in combination with nationally available benchmarking data provided a quantitative starting point for the work. The collaborative elements of the program re-energised the hospital team, who were kept informed by targeted communications, to establish quick wins and build trust and momentum for the more challenging areas.

Motor nerve terminal degeneration provides a potential mechanism for rapid recovery in acute motor axonal neuropathy after Campylobacter infection

We investigated the possible mechanisms of paralysis and recovery in a patient with the acute motor axonal neuropathy (AMAN) pattern of the Guillain-Barré syndrome. The AMAN pattern of GBS is characterized clinically by acute paralysis without sensory involvement and electrodiagnostically by low compound motor action potential amplitudes, suggesting axonal damage, without evidence of demyelination. Many AMAN patients have serologic or culture evidence of recent Campylobacter jejuni infection. Pathologically, the most severe cases are characterized by wallerian-like degeneration of motor axons affecting the ventral roots as well as peripheral nerves, but some fatal cases have only minor changes in the roots and peripheral nerves, and some paralyzed patients with the characteristic electrodiagnostic findings of AMAN recover rapidly. The mechanism of paralysis and recovery in such cases has been uncertain. A 64-year-old woman with culture-proven Campylobacter upsaliensis diarrhea developed typical features of AMAN. She improved quickly following plasmapheresis. Her serum contained IgG anti-GM1 antibodies. The lipopolysaccharide of the organism bound peanut agglutinin. This binding was blocked by cholera toxin, suggesting that the organism contained the Gal(beta1-3)GalNAc epitope of GM1 in its lipopolysaccharide. Motor-point biopsy showed denervated neuromuscular junctions and reduced fiber numbers in intramuscular nerves. In contrast, the sural nerve biopsy was normal and skin biopsy showed normal dermal and epidermal innervation. In AMAN the paralysis may reflect degeneration of motor nerve terminals and intramuscular axons. In addition, the anti-GM1 antibodies, which can bind at nodes of Ranvier, might produce failure of conduction. These processes are potentially reversible and likely to underlie the capacity for rapid recovery that characterizes some cases of AMAN.

Autosomal dominant spinocerebellar ataxia with sensory axonal neuropathy (SCA4): clinical description and genetic localization to chromosome 16q22.1

The hereditary ataxias represent a clinically and genetically heterogeneous group of neurodegenerative disorders. Various classification schemes based on clinical criteria are being replaced as molecular characterization of the ataxias proceeds; so far, seven distinct autosomal dominant hereditary ataxias have been genetically mapped in the human genome. We report linkage to chromosome 16q22.1 for one of these genes (SCA4) in a five-generation family with an autosomal dominant, late-onset spinocerebellar ataxia; the gene is tightly linked to the microsatellite marker D16S397 (LOD score = 5.93 at theta = .00). In addition, we present clinical and electrophysiological data regarding the distinct and previously unreported phenotype consisting of ataxia with the invariant presence of a prominent axonal sensory neuropathy.