National UK Survey of Radiation Doses During Endovascular Aortic Interventions

PURPOSE

Endovascular aortic repair (EAR) interventions, endovascular abdominal aortic repair (EVAR) and thoracic endovascular aortic repair (TEVAR), are associated with significant radiation exposures. We aimed to investigate the radiation doses from real-world practice and propose diagnostic reference level (DRL) for the UK.

MATERIALS AND METHODS

Radiation data and essential demographics were retrospectively collected from 24 vascular and interventional radiology centres in the UK for all patients undergoing EAR-standard EVAR or complex, branched/fenestrated (BEVAR/FEVAR), and TEVAR-between 2018 and 2021. The data set was further categorised according to X-ray unit type, either fixed or mobile. The proposed national DRL is the 75th percentile of the collective medians for procedure KAP (kerma area product), cumulative air kerma (CAK), fluoroscopy KAP and CAK.

RESULTS

Data from 3712 endovascular aortic procedures were collected, including 2062 cases were standard EVAR, 906 cases of BEVAR/FEVAR and 509 cases of TEVAR. The majority of endovascular procedures (3477/3712) were performed on fixed X-ray units. The proposed DRL for KAP was 162 Gy cm2, 175 Gy cm2 and 266 Gy cm2 for standard EVAR, TEVAR and BEVAR/FEVAR, respectively.

CONCLUSION

The development of DRLs is pertinent to EAR procedures as the first step to optimise the radiation risks to patients and staff while maintaining the highest patient care and paving the way for steps to reduce radiation exposures.

Towards a scientific community consensus on designating Vulnerable Marine Ecosystems from imagery

Management of deep-sea fisheries in areas beyond national jurisdiction by Regional Fisheries Management Organizations/Arrangements (RFMO/As) requires identification of areas with Vulnerable Marine Ecosystems (VMEs). Currently, fisheries data, including trawl and longline bycatch data, are used by many RFMO/As to inform the identification of VMEs. However, the collection of such data creates impacts and there is a need to collect non-invasive data for VME identification and monitoring purposes. Imagery data from scientific surveys satisfies this requirement, but there currently is no established framework for identifying VMEs from images. Thus, the goal of this study was to bring together a large international team to determine current VME assessment protocols and establish preliminary global consensus guidelines for identifying VMEs from images. An initial assessment showed a lack of consistency among RFMO/A regions regarding what is considered a VME indicator taxon, and hence variability in how VMEs might be defined. In certain cases, experts agreed that a VME could be identified from a single image, most often in areas of scleractinian reefs, dense octocoral gardens, multiple VME species' co-occurrence, and chemosynthetic ecosystems. A decision flow chart is presented that gives practical interpretation of the FAO criteria for single images. To further evaluate steps of the flow chart related to density, data were compiled to assess whether scientists perceived similar density thresholds across regions. The range of observed densities and the density values considered to be VMEs varied considerably by taxon, but in many cases, there was a statistical difference in what experts considered to be a VME compared to images not considered a VME. Further work is required to develop an areal extent index, to include a measure of confidence, and to increase our understanding of what levels of density and diversity correspond to key ecosystem functions for VME indicator taxa. Based on our results, the following recommendations are made: 1. There is a need to establish a global consensus on which taxa are VME indicators. 2. RFMO/As should consider adopting guidelines that use imagery surveys as an alternative (or complement) to using bycatch and trawl surveys for designating VMEs. 3. Imagery surveys should also be included in Impact Assessments. And 4. All industries that impact the seafloor, not just fisheries, should use imagery surveys to detect and identify VMEs.

Fibroblast expression of CD248 may contribute to exacerbation of microvascular damage during systemic sclerosis

OBJECTIVES

CD248 is a glycoprotein, highly expressed on pericytes and fibroblasts (FBs), that is implicated in the fibrotic process. During angiogenesis, CD248 can promote vessel regression, binding multimerin-2 (MMRN-2). Thus, we investigated the expression of MMRN-2 in systemic sclerosis (SSc)-skin and of CD248 in isolated SSc-FBs. The anti-angiogenic property of CD248+ SSc-FBs was evaluated by co-culturing these cells with healthy control endothelial cells (HC-ECs). The apoptotic effect of CD248 on HC-ECs was evaluated. Finally, the ability of CD248 to prevent activation of VEGF receptor 2 (VEGFR2) was assessed.

METHODS

By IF, MMRN-2 was investigated in SSc-skin and CD248 in SSc FBs. The anti-angiogenic property of CD248+ SSc-FBs was evaluated by HC-ECs/SSc-FBs co-cultures. Lentiviral-induced CD248 short-hairpin RNA delivery was employed for loss-of-function studies in SSc-FBs. HC-ECs were cultured in the presence of CD248 to assess apoptosis by IF and VEGFR2 phosphorylation by western blot.

RESULTS

MMRN-2 expression was increased in skin SSc-ECs, whereas CD248 expression was increased in SSc-FBs. Functionally, CD248+-SSc-FBs suppressed angiogenesis in the organotypic model, as assessed by the reduction in total tube length of HC-ECs. This anti-angiogenetic behaviour was reversed by CD248 silencing. Furthermore, the presence of CD248 promoted the apoptosis of HC-ECs. Finally, CD248 prevented activation of VEGFR2 by reducing its phosphorylation after VEGF stimulation.

CONCLUSION

CD248 was anti-angiogenic in vitro due to a reduction in tube formation and to induction of apoptosis of ECs. Increased expression of CD248 in SSc could contribute to the microvascular rarefaction observed at the tissue level in SSc. Our results suggest a pathogenic role for CD248-MMRN-2 in SSc.

Understanding Online Registry Facilitators and Barriers Experienced by Black Brain Health Registry Participants: The Community Engaged Digital Alzheimer's Research (CEDAR) Study

BACKGROUND

Failure of Alzheimer's disease and related diseases (ADRD) research studies to include and engage Black participants is a major issue, which limits the impact and generalizability of research findings. Little is known about participation of Black adults in online ADRD-related research registries.

OBJECTIVES

As part of the Community Engaged Digital Alzheimer's Research (CEDAR) Study, this study aims to increase our understanding of facilitators and barriers of Black adults to participating in ADRD-related online registries, as well as to understand their preferences for communication channels.

DESIGN, SETTING, PARTICIPANTS, MEASUREMENTS

We invited all Black participants enrolled in the Brain Health Registry (BHR) to complete a cross-sectional online survey. The survey consisted of rating scales and open-text questions asking about their attitudes towards brain health research, reasons for joining and continuing to participate in BHR, difficulties with participating, and preferences for modes of contact and website usage.

RESULTS

Of all invited Black BHR participants (N=3,636), 198 (5.5%) completed the survey. The mean age was 58.4 (SD=11.3), mean years of education were 16.3 (SD=2.4), and 85.5% identified as female. Reported facilitators for joining and continuing to participate in BHR were personal interest (e.g., learning more about own brain health) and altruism (e.g., helping research). Among additional registry features which could encourage return, receiving feedback or scores about BHR tasks was rated the highest. Of those who found BHR participation difficult (21%), the most frequent reason was time burden. The most preferred way of receiving study information was via email. Participants reported that the websites that they used the most were YouTube and Facebook.

DISCUSSION

The results of our study can inform the development of culturally-responsive registry features and engagement efforts to improve inclusion and participation of Black adults in online ADRD research. Providing participants with feedback about their registry performance and reducing the number of registry tasks are among the recommended strategies.

AB0142 EVIDENCE OF TYPE I INTERFERON ACTIVATION DURING VASCULAR MANIFESTATIONS OF SYSTEMIC SCLEROSIS

Background

Vascular involvement in Systemic Sclerosis (SSc) is known to start even before clinical diagnosis, to drive Digital Ulcer disease and later in the disease natural history to cause Pulmonary Artery Hypertension, among other manifestations. Despite the proven immune origin of Scleroderma, vascular involvement is not currently targeted by immune driven interventions. Similarly, little data is available on immune or inflammatory biomarkers and outcome measures of vascular disease in SSc. Digital Artery Volume Index (DAVIX) has been recently proposed as imaging surrogate outcome measure of vascular disease activity in SSc [1].

Objectives

Here we aimed to determine the value of DAVIX as overall biomarker of vascular involvement and its correlation with Type I IFN activation in patients with SSc.

Methods

Eighty-six patients attending our Scleroderma Program were consecutively enrolled for the evaluation of serum IFN score as previously described [2]. Clinical features including presence or history of Digital Ulcers, Presence of Pulmonary Artery Hypertension (PAH) and DLCO, were recorded. Digital Artery Vascular Index (DAVIX) of the dominant hand’s fingers was calculated using time of flight magnetic resonance images analysed through IAG proprietary algorithm, as previously described [1]. Medians were compared by Mann-Whitney-Wilcoxon test, correlation with clinical parameters was performed using Spearman’s or Pearson test, as appropriate (R).

Results

Sixty-two patients fulfilled the 2013 ACR/EULAR classification criteria for SSc (diffuse cutaneous 24.6%, limited cutaneous 75.4%) whereas 23 were classified as Very Early Diagnosis of Scleroderma (Criteria score between 6 and 8). Twenty-three patients had DU disease (History of DUs in the previous 24 weeks, presence of DUs at baseline assessment, or onset of new DUs during the following 24 weeks). Eighteen patients had reduced DLCO (<70) with FVC/DLCO>1.8 (suspected PAH). DAVIX showed a negative correlation with disease duration (r=-0.33 and p=.003) and with FVC/DLCO ratio (r=-0.34 and p=.009). Patients with DU disease presented lower DAVIX than patients without (p=.018).

DAVIX showed a significant correlation with Serum IFN score (r=-0.24, p<0.032). Accordingly, patients classified as IFN-HI had lower DAVIX than those within the IFN-LO group (p=0.016).

Conclusion

DAVIX correlated both with presence of Digital Ulcer disease, DLCO and disease duration. The correlation of DAVIX and Serum IFN score does support the notion of innate immune involvement in vascular disease manifestations of SSc. Prospective testing in the context of Randomised controlled trial will determine the value of DAVIX as surrogate outcome measure of vascular disease severity in SSc.

References

[1]Gjeloshi K, et al. Arthritis Rheumatol. 2020.

[2]Hinchcliff M et al. Arthritis Rheumatol. 2021.

Disclosure of Interests

Stefano Di Donato: None declared, Mike Hughes: None declared, Giuseppina Abignano: None declared, Giovanni Lettieri: None declared, Rebecca Ross: None declared, Enrico De Lorenzis: None declared, Philip O’Connor: None declared, Olga Kubassova Shareholder of: IAG Image Analysis Group, CEO, Francesco Del Galdo: None declared

POS0467 DERSIMELAGON, A NOVEL ORAL MELANOCORTIN 1 RECEPTOR AGONIST, DEMONSTRATES DISEASE-MODIFYING EFFECTS IN PRECLINICAL MODELS OF SYSTEMIC SCLEROSIS

Background

Activation of melanocortin 1 receptor (MC1R) is known to have broad anti-inflammatory and anti-fibrotic effects. The bleomycin (BLM)-induced skin fibrosis murine model is well-established for systemic sclerosis (SSc). α-melanocyte-stimulating hormone, an endogenous ligand of MC1R, inhibits skin fibrosis and MC1R knock-out enhances skin fibrosis in this model. These pieces of evidence suggest that MC1R agonism has potential in the treatment of SSc.

Objectives

Dersimelagon phosphate (MT-7117) is an investigational small molecule that is an orally administered, selective agonist for MC1R. The purpose of this study is to investigate the potential of MT-7117 as a therapeutic agent for SSc by evaluating its efficacy and mechanism of action in complementary preclinical models. The expression and distribution of MC1R in the skin of SSc patients was investigated.

Methods

The effects of MT-7117 on skin fibrosis and lung inflammation were evaluated in BLM-induced SSc murine models that were optimized for prophylactic and therapeutic evaluation. Microarray-based gene expression analysis and serum protein profiling were performed to investigate the mechanism of action of MT-7117 in the BLM-induced SSc models. The effect of MT-7117 on TGF-β-induced activation of human dermal fibroblasts was evaluated in vitro. Immunohistochemical analyses of MC1R expression in skin samples from SSc patients were performed.

Results

Prophylactic treatment with MT-7117 (≥0.3 mg/kg/day p.o.) significantly inhibited the increase in collagen content of the skin, the serum level of surfactant protein D, and the weight of the lungs from BLM-induced skin fibrosis and lung inflammation model. Therapeutic treatment with MT-7117 (≥3 mg/kg/day p.o.) significantly suppressed skin thickening and the numbers of myofibroblasts in pre-established BLM-induced skin fibrosis model. Gene array analysis using the BLM-induced SSc model demonstrated changes in numerous categories related to macrophages, monocytes, and neutrophils, followed by endothelial cell-related categories after treatment with MT-7117. In the analysis that focused on biological functions, categories of inflammatory response, activation of antigen-presenting cells, angiogenesis, atherosclerosis, vasculogenesis, and vaso-occlusion were suppressed by MT-7117. In the analysis that focused on molecular signaling pathways, triggering receptor expressed on myeloid cells-1, IL-6, and oncostatin M involved in inflammation, and peroxisome proliferator-activated receptor that is related to fibrosis were all affected by MT-7117. Serum protein profiling using BLM-induced SSc model revealed that multiple SSc-related biomarkers including P-selectin, osteoprotegerin, cystatin C, growth and differentiation factor-15 and S100A9 were suppressed by MT-7117. MT-7117 inhibited the activation of human dermal fibroblasts by suppressing TGF-β-induced ACTA2 (encoding α-smooth muscle actin) mRNA elevation in vitro. Immunohistochemical analyses showed that MC1R positivity was observed in 40 of 50 diffuse cutaneous SSc patients. MC1R was expressed by monocytes/macrophages, neutrophils, blood vessels (endothelial cells), fibroblasts, and epidermis (keratinocytes) in the skin of SSc patients.

Conclusion

MT-7117 demonstrates disease-modifying effects in preclinical models of SSc. Investigations of its mechanism of action and target expression analyses indicate that MT-7117 exerts its positive effects by affecting the pathologies of inflammation, vascular dysfunction, and fibrosis through inflammatory cells, endothelial cells, and fibroblasts. In view of its potent beneficial impact on all these three main pathologies of SSc, MT-7117 is a potential therapeutic agent for the treatment of clinically challenging SSc, which has diverse and difficult to treat symptoms. A phase 2 clinical trial investigating the efficacy and tolerability of MT-7117 in patients with early, progressive diffuse cutaneous SSc is currently in progress.

Disclosure of Interests

Masahiro Kondo Employee of: Mitsubishi Tanabe Pharma Corporation, Tsuyoshi Suzuki Employee of: Mitsubishi Tanabe Pharma Corporation, Yuko Kawano Employee of: Mitsubishi Tanabe Pharma Corporation, Shinji Kojima Employee of: Mitsubishi Tanabe Pharma Corporation, Masahiko Miyashiro Employee of: Mitsubishi Tanabe Pharma Corporation, Atsuhiro Matsumoto Employee of: Mitsubishi Tanabe Pharma Corporation, Gabriela Kania: None declared, Przemyslaw Blyszczuk: None declared, rebecca ross: None declared, Panji Mulipa: None declared, Francesco Del Galdo Grant/research support from: Prof. F. Del Galdo received fees and research support from Abbvie, AstraZeneca, Boehringer-Ingelheim, Capella, Chemomab, Kymab, Janssen and Mitsubishi-Tanabe., Yun Zhang: None declared, Jörg H.W. Distler Grant/research support from: Prof. J.H.W. Distler received consulting fees, lecture fees, and/or honoraria from Actelion, Active Biotech, Anamar, ARXX, aTyr, Bayer Pharma, Boehringer Ingelheim, Celgene, Galapagos, GSK, Inventiva, JB Therapeutics, Medac, Pfizer, Sanofi-Aventis, RedX, RuiYi and UCB. J. H. W. Distler is stock owner of 4D Science and Scientific head of FibroCure.

POS0876 SERUM INTERFERON SCORE PREDICTS SEVERITY OF PATIENT REPORTED HAND DISABILITY IN SYSTEMIC SCLEROSIS

Background

Hand involvement is a major cause of disability in systemic sclerosis (SSc) patients. Loss of hand function is the result of a complex and overlapping series of manifestations including Raynaud’s, cutaneous ulcerations as well as skin fibrosis, joint inflammation, and contractures. The natural history of hand involvement in SSc and potential biomarkers to predict its outcome are still poorly defined. Type 1 Interferon (IFN) activation has been extensively correlated with skin fibrosis, joint disease activity, vascular manifestations, and poor prognosis in SSc patients.

Objectives

To characterize hand disability burden in SSc and explore its relationship with IFN activation in a national, multicenter, longitudinal, observational cohort of patients with SSc.

Methods

The Cochin Hand Function Scale (CHFS) was assessed in consecutively enrolled SSc patients at baseline and after 12 months. CHFS values above the patient acceptable symptom state (PASS)(CHFS>25)1 were considered as clinically meaningful hand impairment (CMHI). Minimal clinically important difference (MCID) in CHFS for improvement (reduction of 13.1%) and worsening (increase >24.6%) were assessed in longitudinal analysis. Serum IFN score was evaluated as previously described2.

Results

A total of 397 SSc patients from 10 centers (female 85.3%, aged 54.9±11.5 years, white Caucasian 88.2%) were available for longitudinal (12m) analysis. The median disease duration was 9 (IQR 3-16) years, 37.1% of patients had a diffuse cutaneous variant, while anticentromere (ACA) and anti-Scl70 antibody positivity was reported in 41.2% and 33.5% of cases, respectively. Hand digital ulcers, forearm-hand-finger skin score ≥6, and tenosynovitis/arthritis were clinically reported in 24.0%, 15.3%, and 17.9% of patients, respectively. 37.3% of patients reported a CHFS > PASS at baseline. CMHI was associated with male gender (p<.001), diffuse cutaneous variant (p<.001), anti Scl70 positivity (p<.001), ACA negativity (p=.002), and digital ulcers (p=.001). Patients with CMHI had greater serum IFN score than patients with CHFS < PASS (p=.002). In multivariate logistic regression analysis, high serum IFN score remained associated with CHFS>PASS when adjusted for male gender, ACA positivity, anti-Scl70 positive, diffuse subset, and current digital ulcers (OR 2.67, p=.005). Over the 12-month follow-up, vasoactive and immunosuppressive treatment were escalated or introduced in 7.2 and 7.8% of patients, respectively. Median CHFS worsened over time (from 18 (IQR 5-37) to 21 (IQR 6-37), p=.002)) with 32.5% of patients having a clinically meaningful worsening and 32.0% improving their hand function. Functional hand worsening was associated with lower baseline CHFS (p=.001) and ACA negativity (p=.002), while improving with female gender (p=.047), limited cutaneous subset (p=.029), higher baseline CHFS (p=.001), and active baseline tenosynovitis (p=.014).

Conclusion

One third of the patients within our cohort complain of a significant hand impairment. This is associated with higher IFN activation and worsens at group level in patients despite standard of care treatment.

References

[1]Daste C et al. Semin Arthritis Rheum. 2019;48(4):694-700. [2] Hinchcliff M et al. Arthritis Rheumatol. 2021; 73 (suppl 10).

Disclosure of Interests

Enrico De Lorenzis: None declared, Vishal Kakkar: None declared, rebecca ross: None declared, Stefano Di Donato: None declared, Theresa Barnes: None declared, Benazir Saleem: None declared, Ariane Herrick: None declared, Muhammad Nisar: None declared, Catherine Morley: None declared, Karen Douglas: None declared, Christopher P Denton: None declared, Emma Derrett-Smith: None declared, Philip Helliwell Consultant of: PH received consulting fees (Eli Lilly) and fees for educational services (Abbvie, Amgen, Novartis, Janssen), Grant/research support from: PH received consulting fees (Eli Lilly) and fees for educational services (Abbvie, Amgen, Novartis, Janssen), Francesco Del Galdo Consultant of: FDG has received research support and personal fees, not directly related to the content of this study, from

Abbvie, AstraZeneca, Boehringer-Ingelheim, Capella Biosciences, Chemomab LTD, Janssen, Kymab LTD, Mitsubishi-Tanabe, Grant/research support from: FDG has received research support and personal fees, not directly related to the content of this study, from

Abbvie, AstraZeneca, Boehringer-Ingelheim, Capella Biosciences, Chemomab LTD, Janssen, Kymab LTD, Mitsubishi-Tanabe

EP.FRI.960 USS appraisal in females of child bearing age presented with possible appendicitis

Aims

Appendicitis remains the most common acute surgical condition.  No standard guidelines for the use of imaging studies, and there is a discrepancy between the published data regarding accuracy of these modalities and our practical findings. Yet the growing number of USS reported as “appendix not visualized” has led us to rethink about the value of USS in acute appendicitis. 

Methods

A retrospective single centre study for all females (15-45 years) underwent emergency appendectomy for suspected acute appendicitis. Analysis of preoperative clinical, radiographic and postoperative histopathological data was done.

Results

632 cases analysed over 18months, out of those 238 (37%) were females (15-45 years). USS was done in 129(54%) cases. 25(10.5) cases had both USS and CTAP. 32(13%) cases had only CTAP. The mean rate of appendix visualization in the USS was 30%(71cases) two thirds reported by radiologist versus one third by sonographers. Our negative appendectomy rate dropped from 25 to 15% after a positive scan. 

Conclusions

Traditional preference for ultrasound in the UK compared to CTAP in young population is mostly due to the potential hazards of irradiation, but USS commonly does not visualise the appendix in our practice (70%), and has low sensitivity and specificity for appendicitis.  However, following a positive USS, NAR dropped to 15%. Radiologists had a higher visualization rate of appendix compared to sonographers. Commitment to improve the performance of ultrasonography by allocating adequately timed sessions to the most experienced radiologists and increasing the use of low dose CT scans are possible solutions.

EP.FRI.96 Negative appendectomy rate in young females, between theory and practice. Full audit cycle

Aims

Females of child bearing age are at higher risk of negative appendectomy rate, the accepted overall NAR is up to (20-25%). Presented is our study to examine the real NAR in the female’s cohort aged (15-45 years) in the form of quality improvement project to improve patient’s outcome.

Methodology

Retrospective study in the form of Full audit cycle over 18 months, the first cycle was conducted over 12 months period, followed by the action plan and reassessment over 6 months. Preoperative clinical, laboratory, radiographic and histopathological data were collected.

Results

Over the whole audit period 632 cases were analysed, 238 cases were females in the child bearing age included in our cohort. Over the first phase 419 appendectomy cases were performed, among those 156(37%) were females in child bearing age. Overall NAR was 29% and in our females cohort was 43.5%. Over the second cycle, 213 cases performed, out of which 82(38%) cases included in our cohort. Overall NAR reduced to 25% and in our cohort was 37%

Conclusions

Despite the advances in diagnostic modalities, Females are at significantly higher risk of NAR 37%. Our overall NAR reduced from 29% to 25% compared to the young females cohort, the rate dropped from 43% to 37%. specific consideration and regular auditing of results regards this cohort are highly recommended. Validation of appendicitis scores for risk stratification, Serial examinations and radiological adjuncts are possible solutions to reduce the NAR among this group.

Dissemination and implementation of national physical activity, sedentary behaviour, and/or sleep guidelines among community-dwelling adults aged 18 years and older: a systematic scoping review and suggestions for future reporting and research

Strategies for dissemination (purposive distribution of a guideline to specific audiences) and implementation (actions to support the general public in meeting guideline recommendations/behavioural benchmarks) of national movement guidelines (physical activity (PA), sedentary behaviour, and sleep) have yet to be synthesized. The purpose of this systematic scoping review was to identify strategies for dissemination and implementation of national PA, sedentary behaviour, and/or sleep guidelines among community-dwelling adults (aged >18 years) and/or stakeholders in Canada and analogous countries. Five search approaches (e.g., published literature, grey literature, targeted web-based, custom Google, and content expert consultation) identified records (e.g., empirical studies, organizational reports, website pages, or guideline messages) that discussed and/or evaluated dissemination or implementation strategies for a prespecified list of guidelines. A modified strategy classification system was developed to chart the data. Forty-seven reports met inclusion criteria. Dissemination strategies (n = 42) were more frequently reported than implementation strategies (n = 24). Implementation strategies were more frequently evaluated (n = 13 vs. 7 dissemination strategies) and associated with positive outcomes. The 13 studies that evaluated strategies were at high or serious risk of bias. We identified limited information about the dissemination and implementation of national movement guidelines and identified strategies were rarely evaluated. Greater efforts are required to increase the impact of guidelines among the general public and stakeholders and to build the evidence base in this field. (Open Science Framework registration: https://osf.io/4tyw3.) Novelty An adapted movement guideline dissemination and implementation strategy classification framework is provided. Knowledge translation efforts should be documented and evaluated to advance science and practice in the movement guideline field.

POS0425 INCREASED KERATIN 9 EXPRESSION IN SYSTEMIC SCLEROSIS SKIN IS DRIVEN BY THE lncRNA HOTAIR FROM FIBROBLAST DERIVED EXOSOMES

Background:

Skin fibrosis is the hallmark fibrotic manifestation of systemic sclerosis (SSc). Despite a key role of tissue fibroblasts, skin changes extend to the keratinocyte layer, which contribute to the loss of skin function. RNA seq. analysis of SSc patient forearm skin showed that palmoplantar specific Keratin 9 (CK9) was highly expressed (1). SSc affected skin shares several features with palmoplantar skin including increased keratinocyte layer thickness and lack of hair. Seminal work of last decade has shown that long noncoding RNA in the HOX loci play a crucial role in skin keratinocyte differentiation (2), with the lncRNA HOTAIR being one of the HOX lncRNA mostly expressed in the palmoplantar region.

Objectives:

Following recent data suggesting a role of HOTAIR in the profibrotic phenotype of dermal fibroblasts in SSc (3), here we set out to determine if HOTAIR expressed in SSc dermal fibroblasts was a contributing factor to the high levels of CK9 found in SSc patient skin

Methods:

Full-thickness skin biopsies were surgically obtained from the forearms of patients with SSc of recent onset. Fibroblasts were isolated and cultured in monolayers. HOX transcript antisense RNA (HOTAIR) was expressed in healthy dermal fibroblasts by lentiviral induction employing a vector containing the specific sequence. Exosomes were isolated from dermal fibroblast media using the Total exosome isolation reagent (Thermo Fisher). Enhancer of zeste 2 (EZH2) was blocked with GSK126 inhibitor. Skin equivalents were created using scramble and HOTAIR expressing fibroblasts with primary keratinocytes

Results:

Media from both SSc patient fibroblasts and HOTAIR expressing fibroblasts induced CK9 expression in healthy keratinocytes in vitro. In addition, HOTAIR expressing fibroblasts induces CK9 expression in keratinocytes in 3D skin equivalent models. Media fractionation studies indicated that HOTAIR was present in fibroblasts exosomes and found at a higher concentration (2.7 fold p=0.01) in exosomes from SSc fibroblasts. Importantly, transfection of Exosomal RNAs from SSc fibroblasts could reproduce the increase in CK9 in keratinocytes. Mechanistically, CK9 induction was mediated by changes to the histone methylation profile in the keratinocytes through EZH2.

Conclusion:

Pro-fibrotic dermal fibroblasts in systemic sclerosis contribute to the overall skin loss of function by inducing CK9 in adjacent keratinocytes through transfer of the long non-coding RNA HOTAIR. Unraveling the crosstalk of activated fibroblasts with adjacent cells may lead to identify therapeutic targets to re-establish tissue homeostasis and function during fibrosis.

References:

[1]Assassi S et.al Arthritis and Rheumatology 2015

[2]Rinn JL et.al Cell 2007

[3]Wasson CW et.al Annals of Rheumatic Disease 2020

Disclosure of Interests:

Chris Wasson: None declared, rebecca ross: None declared, Jessica Bryon: None declared, Francesco Del Galdo Speakers bureau: Speakers bureau: Astra-Zeneca, Boehringer Ingelheim, Actelion, Consultant of: Astra-Zeneca, Mitsubishi-Tanabe, Capella Biosciences, Chemomab, Actelion, Boehringer-Ingelheim, Grant/research support from: Grant/research support from: Capella Biosciences, Chemomab, Kymab, Mitsubishi-Tanabe

P149 The intracellular chloride channel 4 (CLIC4) plays an important role in systemic sclerosis fibroblast activation

Background/Aims 

The intracellular chloride ion channel CLIC4 mediates the activation of cancer associated fibroblasts. Interestingly, systemic sclerosis (SSc) fibroblasts display a number of similar properties to cancer associated fibroblasts. Tissue fibrosis in SSc is driven by active fibroblasts (myofibroblasts). Therefore in this study we investigated the role of CLIC4 in SSc fibroblast activation.

Methods 

Dermal fibroblasts were obtained from full thickness skin biopsies from SSc patients (early-diffuse). RNA and protein were collected from the fibroblasts and CLIC4 transcript and protein levels were assessed by qPCR and western blot. SSc patient fibroblasts were treated with the chloride ion channel inhibitors NPPB and IAA-94.

Results 

CLIC4 was found to be expressed at significantly higher levels in SSc patients fibroblasts compared to healthy controls, at both the transcript (3.7 fold) and protein (1.7 fold) levels. Inhibition of the TGF-β signalling pathway led to reduced CLIC4 expression in SSc fibroblasts, confirming this pathway as the main driver of CLIC4 expression. Finally, treatment of SSc fibroblasts with small molecule inhibitors that target the channel led to reduced expression of the myofibroblast markers collagen type 1 and alpha-smooth muscle actin, suggesting a direct role for CLIC4 in SSc associated skin fibrosis.

Conclusion 

We have identified a novel role for CLIC4 in SSc myofibroblast activation, which further strengthen the similarities between SSc fibroblasts and cancer associated fibroblasts. Furthermore this study highlights this channel as a novel target for therapeutic intervention.

Disclosure 

C. Wasson: None. R. Ross: None. R. Morton: None. J. Mankouri: None. F. Del Galdo: None.

Coronavirus-19 (SARS-CoV-2) induces acute severe lung inflammation via IL-1 causing cytokine storm in COVID-19: a promising inhibitory strategy

SARS-Cov-2 infection causes local and systemic inflammation mediated by pro-inflammatory cytokines and COX-2 eicosanoid products with metabolic dysfunction and tissue damage that can lead to patient death. These effects are primarily induced by IL-1 cytokines, which are involved in the elevation of hepatic acute phase proteins and fever. IL-1 has a broad spectrum of biological activities and participates in both innate and acquired immunity. In infections, IL-1 induces gene expression and synthesis of several cytokines/chemokines in both macrophages and mast cells (MCs). The activation of MCs triggers the secretion of mediators stored in the granules, and the de novo synthesis of pro-inflammatory cytokines. In microorganism infections, the release of IL-1 macrophage acts on adhesion molecules and endothelial cells leading to hypotension and septic shock syndrome. IL-1 activated by SARS-CoV-2 stimulates the secretion of TNF, IL-6 and other cytokines, a pro-inflammatory complex that can lead to cytokine storm and be deleterious in both lung and systemically. In SARS-CoV-2 septic shock, severe metabolic cellular abnormalities occur which can lead to death. Here, we report that SARS-CoV-2 induces IL-1 in macrophages and MCs causing the induction of gene expression and activation of other pro-inflammatory cytokines. Since IL-1 is toxic, its production from ubiquitous MCs and macrophages activated by SARS-CoV-2 can also provokes both gastrointestinal and brain disorders. Furthermore, in these immune cells, IL-1 also elevates nitric oxide, and the release of inflammatory arachidonic acid products such as prostaglndins and thromboxane A2. All together these effects can generate cytokine storm and be the primary cause of severe inflammation with respiratory distress and death. Although, IL-1 administered in low doses may be protective; when it is produced in high doses in infectious diseases can be detrimental, therefore, IL-1 blockade has been studied in many human diseases including sepsis, resulting that blocking it is absolutely necessary. This definitely nurtures hope for a new effective therapeutic treatment. Recently, two interesting anti-IL-1 cytokines have been widely described: IL-37 and IL-1Ra. IL-37, by blocking IL-1, has been observed to have anti-inflammatory action in rodents in vivo and in transfected cells. It has been reported that IL-37 is a very powerful protein which inhibits inflammation and its inhibition can be a valid therapeutic strategy. IL-37 is a natural suppressor of inflammation that is generated through a caspase-1 that cleaves pro-IL-37 into mature IL-37 which translocates to the nucleus and inhibits the transcription of pro-inflammatory genes; while IL-1Ra inhibits inflammation by binding IL-1 to its IL-1R (receptor). We firmly believe that blocking IL-1 with an anti-inflammatory cytokine such as IL-37 and/or IL-1Ra is an effective valid therapy in a wide spectrum of inflammatory disorders including SARS-CoV-2-induced COVID-19. Here, we propose for the first time that IL-37, by blocking IL-1, may have an important role in the therapy of COVID-19.

IL-1 induces throboxane-A2 (TxA2) in COVID-19 causing inflammation and micro-thrombi: inhibitory effect of the IL-1 receptor antagonist (IL-1Ra)

IL-1 induces a significant number of metabolic and hematological changes. In experimental animals, IL-1 treatments cause hypotension due to rapid reduction of systemic blood pressure, reduced vascular resistance, increased heart rate and leukocyte aggregations. IL-1 causes endothelial dysfunction, the triggering factor of which may be of a different nature including pathogen infection. This dysfunction, which includes macrophage intervention and increased protein permeability, can be mediated by several factors including cytokines and arachidonic acid products. These effects are caused by the induction of IL-1 in various pathologies, including those caused by pathogenic viral infections, including SARS-CoV-2 which provokes COVID-19. Activation of macrophages by coronavirus-19 leads to the release of pro-inflammatory cytokines, metalloproteinases and other proteolytic enzymes that can cause thrombi formation and severe respiratory dysfunction. Patients with COVID-19, seriously ill and hospitalized in intensive care, present systemic inflammation, intravascular coagulopathy with high risk of thrombotic complications, and venous thromboembolism, effects mostly mediated by IL-1. In these patients the lungs are the most critical target organ as it can present an increase in the degradation products of fibrin, fibrinogen and D-dimer, with organ lesions and respiratory failure. It is well known that IL-1 induces itself and another very important pro-inflammatory cytokine, TNF, which also participates in hemodynamic states, including shock syndrome in COVID-19. Both IL-1 and TNF cause pulmonary edema, thrombosis and bleeding. In addition to hypotension and resistance of systemic blood pressure, IL-1 causes leukopenia and thrombocytopenia. The formation of thrombi is the main complication of the circulatory system and functionality of the organ, and represents an important cause of morbidity and mortality. IL-1 causes platelet vascular thrombogenicity also on non-endothelial cells by stimulating the formation of thromboxane A2 which is released into the inflamed environment. IL-1 is the most important immune molecule in inducing fever, since it is involved in the metabolism of arachidonic acid which increases from vascular endothelial organs of the hypothalamus. The pathogenesis of thrombosis, vascular inflammation and angigenesis involves the mediation of the activation of the prostanoid thromboxane A2 receptor. In 1986, in an interesting article (Conti P, Reale M, Fiore S, Cancelli A, Angeletti PU, Dinarello CA. In vitro enhanced thromboxane B2 release by polymorphonuclear leukocytes and macrophages after treatment with human recombinant interleukin 1. Prostaglandins. 1986 Jul;32(1):111-5), we reported for the first time that IL-1 induces thromboxane B2 (TxB2) releases in activated neutrophils and macrophages. An increase in thromboxane can induce leukocyte aggregation and systemic inflammation, which would account for the dramatic thrombi formation and organ dysfunction. Hence, IL-1 stimulates endothelial cell-leukocyte adhesion, and TxB2 production. All these events are supported by the large increase in neutrophils that adhere to the lung and the decrease in lymphocytes. Therefore, ecosanoids such as TxA2 (detected as TxB2) have a powerful action on vascular inflammation and platelet aggregation, mediating the formation of thrombi. The thrombogenesis that occurs in COVID-19 includes platelet and cell aggregation with clotting abnormalities, and anti-clotting inhibitor agents are used in the prevention and therapy of thrombotic diseases. Prevention of or induction of TxA2 avoids thrombi formation induced by IL-1. However, in some serious vascular events where TxA2 increases significantly, it is difficult to inhibit, therefore, it would be much better to prevent its induction and generation by blocking its inductors including IL-1. The inhibition or lack of formation of IL-1 avoids all the above pathological events which can lead to death of the patient. The treatment of innate immune cells producing IL-1 with IL-1 receptor antagonist (IL-1Ra) can avoid hemodynamic changes, septic shock and organ inflammation by carrying out a new therapeutic efficacy on COVID-19 induced by SARS-CoV-2.

Mast cells activated by SARS-CoV-2 release histamine which increases IL-1 levels causing cytokine storm and inflammatory reaction in COVID-19

SARS-CoV-2 virus is an infectious agent commonly found in certain mammalian animal species and today also in humans. SARS-CoV-2, can cause a pandemic infection with severe acute lung injury respiratory distress syndrome in patients with COVID-19, that can lead to patient death across all ages. The pathology associated with pandemic infection is linked to an over-response of immune cells, including virus-activated macrophages and mast cells (MCs). The local inflammatory response in the lung that occurs after exposure to SARS-CoV-2 is due to a complex network of activated inflammatory innate immune cells and structural lung cells such as bronchial epithelial cells, endothelial cells and fibroblasts. Bronchial epithelial cells and fibroblasts activated by SARS-CoV-2 can result in the up-regulation of pro-inflammatory cytokines and induction of MC differentiation. In addition, endothelial cells which control leukocyte traffic through the expression of adhesion molecules are also able to amplify leukocyte activation by generating interleukin (IL)-1, IL-6 and CXC chemokines. In this pathologic environment, the activation of mast cells (MCs) causes the release of histamine, proteases, cytokines, chemokines and arachidonic acid compounds, such as prostaglandin D2 and leukotrienes, all of which are involved in the inflammatory network. Histamine is stored endogenously within the secretory granules of MCs and is released into the vessels after cell stimulation. Histamine is involved in the expression of chemokine IL-8 and cytokine IL-6, an effect that can be inhibited by histamine receptor antagonists. IL-1 is a pleiotropic cytokine that is mainly active in inflammation and immunity. Alveolar macrophages activated by SARS-CoV-2 through the TLR produce IL-1 which stimulates MCs to produce IL-6. IL-1 in combination with IL-6 leads to excessive inflammation which can be lethal. In an interesting study published several years ago (by E. Vannier et al., 1993), it was found that histamine as well as IL-1 are implicated in the pathogenesis of pulmonary inflammatory reaction, after micorganism immune cell activation. IL-1 in combination with histamine can cause a strong increase of IL-1 levels and, consequently, a higher degree of inflammation. However, it has been reported that histamine alone has no effect on IL-1 production. Furthermore, histamine enhances IL-1-induced IL-6 gene expression and protein synthesis via H2 receptors in peripheral monocytes. Therefore, since MCs are large producers of histamine in inflammatory reactions, this vasoactive amine, by increasing the production of IL-1, can amplify the inflammatory process in the lung infected with SARS-CoV-2. Here, we have proposed for the first time an emerging role for histamine released by MCs which in combination with IL-1 can cause an increase in lung inflammation induced by the viral infection SARS-CoV-2.

SARS-CoV-2, which induces COVID-19, causes kawasaki-like disease in children: role of pro-inflammatory and anti-inflammatory cytokines

Acute severe respiratory syndrome coronavirus-2 (SARS-CoV-2) caused a global pandemic coronavirus disease 2019 (COVID-19). In humans, SARS-CoV-2 infection leads to acute respiratory distress syndrome which presents edema, hemorrhage, intra-alveolar fibrin deposition, and vascular changes characterized by thrombus formation, micro-angiopathy and thrombosis. These clinical signs are mediated by pro-inflammatory cytokines. In recent studies it has been noted that COVID-19 pandemic can affect patients of all ages, including children (even if less severely) who were initially thought to be immune. Kawasaki disease is an autoimmune acute febrile inflammatory condition, which primarily affects young children. The disease can present immunodeficiency with the inability of the immune system to fight inflammatory pathogens and leads to fever, rash, alterations of the mucous membranes, conjunctiva infection, pharyngeal erythema, adenopathy, and inflammation. In the COVID-19 period, virus infection aggravates the condition of Kawasaki disease, but it has also been noted that children affected by SARS-V-2 may develop a disease similar to Kawasaki's illness. However, it is uncertain whether the virus alone can give Kawasaki disease-like forms. As in COVID-19, Kawasaki disease and its similar forms are mediated by pro-inflammatory cytokines produced by innate immunity cells such as macrophages and mast cells (MCs). In light of the above, it is therefore pertinent to think that by blocking pro-inflammatory cytokines with new anti-inflammatory cytokines, such as IL-37 and IL-38, it is possible to alleviate the symptoms of the disease and have a new available therapeutic tool. However, since Kawasaki and Kawasaki-like diseases present immunodeficiency, treatment with anti-inflammatory/immunosuppressant molecules must be applied very carefully.

Changing Learner Beliefs in South African Townships: An Evaluation of a Growth Mindset Intervention

We tested the effectiveness of a growth mindset intervention for N = 354 adolescents from low resource schools in the Western Cape, South Africa. Growth mindset measures demonstrated good psychometric properties in our sample. We found mixed evidence of an intervention effect: We did not find evidence that the intervention improved mastery behavior or math achievement test scores, but treatment-on-the-treated (TOT) analyses showed positive effects on growth mindset for those who received the intervention (0.32 SDs). TOT analyses provided some evidence for effects on math grades, comparable in magnitude with previous research (0.24–0.34 SDs), although tests were underpowered and not all reached significance. The intervention cost approximately R4.4 (31 U.S. cents) per student. A growth mindset intervention may be a low-cost way to shape motivation and grades for those attending low resource schools, but more research is needed to address the mixed results obtained in the current study.

How to reduce the likelihood of coronavirus-19 (CoV-19 or SARS-CoV-2) infection and lung inflammation mediated by IL-1

SARS-CoV-2, also referred to as CoV-19, is an RNA virus which can cause severe acute respiratory diseases (COVID-19), with serious infection of the lower respiratory tract followed by bronchitis, pneumonia and fibrosis. The severity of the disease depends on the efficiency of the immune system which, if it is weak, cannot stem the infection and its symptoms. The new CoV-19 spreads in the population at a rate of 0.8-3% more than normal flu and mostly affects men, since immune genes are more expressed on the X chromosome. If CoV-19 would spread with a higher incidence rate (over 10%), and affect the people who live in closed communities such as islands, it would cause many more deaths. Moreover, people from the poorest classes are most at risk because of lack of health care and should be given more assistance by the competent authorities. To avoid the aggravation of CoV-19 infection, and the collapse of the health system, individuals should remain at home in quarantine for a period of approximately one month in order to limit viral transmission. In the case of a pandemic, the severe shortage of respirators and protective clothing, due to the enormous demand and insufficient production, could lead the CoV-19 to kill a large number of individuals. At present, there is no drug capable of treating CoV-19 flu, the only therapeutic remedies are those aimed at the side effects caused by the virus, such as inflammation and pulmonary fibrosis, recognized as the first causes of death. One of the COVID-19 treatments involves inhaling a mixture of gaseous hydrogen and oxygen, obtaining better results than with oxygen alone. It was also noted that individuals vaccinated for viral and/or bacterial infectious diseases were less likely to become infected. In addition, germicidal UV radiation "breaks down" the oxygen O2 which then aggregate into O3 (ozone) molecules creating the ozone layer, capable of inhibiting viral replication and improving lung respiration. All these precautions should be taken into consideration to lower the risk of infection by CoV-19. New anti-viral therapies with new drugs should also be taken into consideration. For example, microbes are known to bind TLR, inducing IL-1, a pleiotropic cytokine, highly inflammatory, mediator of fever and fibrosis. Therefore, drugs that suppress IL-1 or IL-1R, also used for the treatment of rheumatoid arthritis are to be taken into consideration to treat COVID-19. We strongly believe that all these devices described above can lead to greater survival and. therefore, reduction in mortality in patients infected with CoV-19.

Induction of pro-inflammatory cytokines (IL-1 and IL-6) and lung inflammation by Coronavirus-19 (COVI-19 or SARS-CoV-2): anti-inflammatory strategies

Coronavirus-19 (COVI-19) involves humans as well as animals and may cause serious damage to the respiratory tract, including the lung: coronavirus disease (COVID-19). This pathogenic virus has been identified in swabs performed on the throat and nose of patients who suffer from or are suspected of the disease. When COVI-19 infect the upper and lower respiratory tract it can cause mild or highly acute respiratory syndrome with consequent release of pro-inflammatory cytokines, including interleukin (IL)-1β and IL-6. The binding of COVI-19 to the Toll Like Receptor (TLR) causes the release of pro-IL-1β which is cleaved by caspase-1, followed by inflammasome activation and production of active mature IL-1β which is a mediator of lung inflammation, fever and fibrosis. Suppression of pro-inflammatory IL-1 family members and IL-6 have been shown to have a therapeutic effect in many inflammatory diseases, including viral infections. Cytokine IL-37 has the ability to suppress innate and acquired immune response and also has the capacity to inhibit inflammation by acting on IL-18Rα receptor. IL-37 performs its immunosuppressive activity by acting on mTOR and increasing the adenosine monophosphate (AMP) kinase. This cytokine inhibits class II histocompatibility complex (MHC) molecules and inflammation in inflammatory diseases by suppressing MyD88 and subsequently IL-1β, IL-6, TNF and CCL2. The suppression of IL-1β by IL-37 in inflammatory state induced by coronavirus-19 can have a new therapeutic effect previously unknown. Another inhibitory cytokine is IL-38, the newest cytokine of the IL-1 family members, produced by several immune cells including B cells and macrophages. IL-38 is also a suppressor cytokine which inhibits IL-1β and other pro-inflammatory IL-family members. IL-38 is a potential therapeutic cytokine which inhibits inflammation in viral infections including that caused by coronavirus-19, providing a new relevant strategy.

Experimental Assessment of Two Non-Contrast MRI Sequences Used for Computational Fluid Dynamics: Investigation of Consistency Between Techniques

Purpose

Recent studies have noted a degree of variance between the geometries segmented by different groups from 3D medical images that are used in computational fluid dynamics (CFD) simulations of patient-specific cardiovascular systems. The aim of this study was to determine if the applied sequence of magnetic resonance imaging (MRI) also introduced observable variance in CFD results.

Methods

Using a series of phantoms MR images of vessels of known diameter were assessed for the time-of-flight and multi-echo data image combination sequences. Following this, patient images of arterio-venous fistulas were acquired using the same sequences. Comparisons of geometry were made using the phantom and patient images, and of wall shear stress quantities using the CFD results from the patient images.

Results

Phantom images showed deviations in diameter between 0 and 15% between the sequences, depending on vessel diameter. Patient images showed different geometrical features such as narrowings that were not present on both sequences. Distributions of wall shear stress (WSS) quantities differed from simulations between the geometries obtained from the sequences.

Conclusion

In conclusion, choosing different MRI sequences resulted in slightly different geometries of the same anatomy, which led to compounded errors in WSS quantities from CFD simulation.

Electronic supplementary material

The online version of this article (10.1007/s13239-020-00473-z) contains supplementary material, which is available to authorized users.

An Adaptive Search Algorithm for Detecting Respiratory Artifacts Using a Wireless Passive Wearable Device

With the use of a wireless, wearable, passive knitted smart fabric device as a strain gauge sensor, the proposed algorithm can estimate biomedical feedback such as respiratory activity. Variations in physical properties of Radio Frequency Identification (RFID) signals can be used to wirelessly detect physiological processes and states. However, it is typical for ambient noise artifacts to appear in the RFID signal making it difficult to identify physiological processes. This paper introduces a new technique for finding these repetitive physiological signals and identifying them into two states, active and inactive, using k-means clustering. The algorithm detects these biomedical events without the need to completely remove the noise components using a semi-unsupervised approach, and with these results, predict the next biomedical event using these classification results. This approach enables real-time noninvasive monitoring for use with actuating medical devices for therapy. Using this approach, the algorithm predicts the onset of respiratory activity in a simulated environment within approximately one second.

SAT0281 BIOSAMPLES FROM AT RISK SSC PATIENTS SHOW CLASSIC PATHOLOGICAL SIGNS OF SCLERODERMA: OPPORTUNITY FOR DIAGNOSIS OF PRE-CLINICAL SSC

Background:

The VEDOSS study has recently indicated that more than 80% of patients affected by Raynaud’s phenomenon (RP) with specific SSc auto-antibodies and capillaroscopy changes satisfied ACR/EULAR 2013 criteria within 5 years. These data suggest that there is a window of opportunity for early detection of SSc in these patients.

Objectives:

Here we aimed to determine whether sera, skin biopsies and skin fibroblasts cultured from these patients showed any biomarker sign of SSc.

Methods:

Fifty-nine at risk patients identified by having RP and SSc auto-antibodies or capillaroscopy pattern (or both) were enrolled in the Kennedy national inception cohort. Sera were tested for IFN inducible chemokines (CXCL-9,10 and 11 and CCL2, 8 and 19) and biomarker of extracellular matrix turnover (ELF test), all previously shown to be increased in SSc. Further, two 3mm skin biopsies were taken from the forearms from 3 ACA+ve (anti-centromere antibodies), 3 SCL70+ve patients. One biopsy was subjected to histology analysis, including haematoxylin and eosin staining and immunohistological staining for Collagen Type 1, alpha-SMA, Caveolin 1 and CD31 as endothelial marker. The other biopsy was used to explant fibroblasts cultures. mRNA and protein were isolated from primary fibroblasts and processed for RT-qPCR and western blotting analyses.

Results:

Sera from at risk patients showed overall higher IFN inducible chemokines and ELF test (P<0.05) with bimodal distribution among patients. Skin biopsies from both ACA or SCL70+ve patients showed decreased number of CD31+ cells, increased number of myofibroblasts and increased collagen bundles within the dermis, as usually seen in SSc, compared to healthy controls. In vitro, fibroblasts from both ACA or SCL70+ve patients showed average 10-fold higher collagen mRNA levels and 31-fold increased collagen protein levels

compared to healthy control fibroblasts. Furthermore, fibroblasts from ACA or SCL70+ve patients showed limited TGF-beta induced increase in collagen and SMA expression, similar to SSc fibroblasts.

Conclusion:

Although pilot in nature, this study suggests that patients “at risk” already show biomarker signs of SSc both in their sera, at skin biopsy and fibroblast level. Longitudinal studies on patients at this stage of pre-clinical disease may inform on the stratification strategies for imminent progression to clinical manifestations, and offer both insights on pathogenesis of clinical signs and a window of opportunity for delaying the onset clinical intervention trials.

Disclosure of Interests:

rebecca ross: None declared, Ioanna Georgiou: None declared, Antonio Carriero: None declared, Giuseppina Abignano: None declared, Chris Wasson: None declared, Gemma Migneco: None declared, Ariane Herrick: None declared, Christopher Denton Grant/research support from: GlaxoSmithKline, CSL Behring, and Inventiva, Consultant of: Medscape, Roche-Genentech, Actelion, GlaxoSmithKline, Sanofi Aventis, Inventiva, CSL Behring, Boehringer Ingelheim, Corbus Pharmaceuticals, Acceleron, Curzion and Bayer, Francesco Del Galdo: None declared

O30 Long non-coding RNA HOTAIR induces beta catenin expression in systemic sclerosis through EZH2 dependent repression of Axin-2

Background

Fibroblasts explanted from affected tissues in systemic sclerosis (SSc) maintain their pro-fibrotic phenotype in vitro. This includes increased secretion of collagens and other extracellular matrix proteins and increased proportion of α-Smooth Muscle Actin (α-SMA) positive cells (myofibroblasts). It has been previously shown that among their profibrotic features, myofibroblasts display activation of WNT signalling, which is linked to a decreased basal expression of AXIN2. Here we aimed to determine whether specific long non-coding RNA (lncRNAs) expressed in myofibroblasts could drive the epigenetically stable decreased expression of Axin 2 in vitro.

Methods

Full thickness skin biopsies were surgically obtained from the forearms of twelve adult patients with SSc of recent onset. Fibroblasts were isolated and cultured in monolayers and protein and RNA extracted from the fibroblast cultures. Laser capture was performed to isolate cells expressing or not α-SMA as a marker of myofibroblast differentiation. LncRNA HOTAIR was overexpressed in healthy dermal fibroblasts by lentiviral induction. EZH2 was blocked in cultured fibroblasts with the specific inhibitor GSK126.

Results

HOTAIR expression was increased in SSc patients’ skin (100 fold) and in SSc explanted fibroblasts (5 fold; p &lt; 0.001 for both). Further, laser captured α-SMA expressing fibroblasts expressed in average 2.5 fold higher HOTAIR RNA levels compared to α -SMA negative cells from the same donors (P &lt; 0.05). In vitro, lentiviral induced stable overexpression of HOTAIR in healthy dermal fibroblasts led to their profibrotic activation, including significantly increased expression of Col1A1 and α-SMA both at mRNA and protein levels (2.8 and 1.8 fold respectively, p &lt; 0.05). We further showed that HOTAIR-induced profibrotic activation was due to EZH2 dependent spread of H3k27me3 methylation marker, as demonstrated by complete inhibition by treatment with GSK126. HOTAIR driven EZH2 histone methylation suppressed the expression of Axin 2 in SSc fibroblasts. The reduced Axin 2 levels led to stabilisation of beta catenin and WNT signalling pathway activation.

Conclusion

Here we show that the epigenetically stable activation of SSc dermal fibroblasts is due to HOTAIR. We also identified a major downstream target of HOTAIR is Axin-2. The results of these studies identify a new venue to modulate fibroblasts biology which could inform clinical research to resolve chronic fibrosis and re-establish tissue homeostasis in SSc.

Disclosures

C.W. Wasson None. G. Abignano None. R. Ross None. F. Del Galdo Consultancies; AstraZeneca, GSK, Boehringer-Ingelheim, Actelion, Capella Biosciences, Chemomab.

Passive anti-C acquired in the setting of Rh immune globulin administration following Rh mismatched apheresis platelet transfusion: A case series

Rh immune globulin (RhIG) may be administered to Rh(D)-negative recipients of Rh(D)-positive platelet (PLT) transfusions to mitigate anti-D alloantibody formation. We report a series of seven patients in which anti-C was detected as a result of RhIG administered as immunoprophylaxis following Rh-mismatched apheresis PLT transfusion, persisting for a range of 27 to 167 days post-RhIG. The passively transferred anti-C antibodies created complexities for subsequent transfusion support. Based on these challenges, in combination with emerging evidence supporting an extremely low anti-D alloimmunization risk following Rh-mismatched apheresis PLTs, we have changed our practice and now limit RhIG immunoprophylaxis in this setting to women of reproductive age. In summary, the blood bank and apheresis communities should be aware that passive transfer of non-D antibodies is possible following RhIG administration. This phenomenon represents a compelling reason to consider the risk/benefit ratio of RhIG and to limit its use to situations in which it is clinically necessary.

38 Improving Access to Outpatient Services for Older People Using A Clinical Microsystems Approach

Background

Northumbria Healthcare NHS Foundation Trust provides services to more than 500,000 residents in the North-East of England across multiple sites.

Local problem

Outpatient services for older people across Northumbria include specialist (eg falls) and generic clinics with differing referral routes, demands and waiting times. Referrals derive from primary care, emergency services and elsewhere; some are complex patients requiring a comprehensive geriatric assessment (CGA). Existing pathways led to variable waits for clinics, duplication and delays.

Aim was to improve the timeliness, efficiency and access to appropriate assessment first time.

Methods

We adopted a Clinical Microsystems approach (Sheffield Microsystems Coaching Academy) for improvement. Main components were team coaching, weekly “Big Room” meeting of involved staff to share understanding of current process, agree change ideas, and test these with multiple plan, do, study, act (PDSA) cycles. Impacts of each PDSA cycle were discussed in Big Room, leading to refinement of the pathway.

Interventions

Results: PDSA interventions were tested over 6 months: Development of a single triage systemCGA clinic for frail older patients.Development of shared documentation for CGA.Improved cycle and lead times for assessment

Conclusions

Our quality improvement work supported the development and implementation of a new referral triage process with CGA assessment for complex frail patients. The change has reduced patient wait times, provided early intervention and reduced duplication. Work is ongoing to determine impact on patient satisfaction and time to discharge from clinic. The approach taken by this project could be applied elsewhere to improve outpatient referral processes.

Blood Utilization and Transfusion Reactions in Pediatric Patients Transfused with Conventional or Pathogen Reduced Platelets

OBJECTIVES

To assess the safety and efficacy of a Food and Drug Administration-approved pathogen-reduced platelet (PLT) product in children, as ongoing questions regarding their use in this population remain.

STUDY DESIGN

We report findings from a quality assurance review of PLT utilization, associated red blood cell transfusion trends, and short-term safety of conventional vs pathogen-reduced PLTs over a 21-month period while transitioning from conventional to pathogen-reduced PLTs at a large, tertiary care hospital. We assessed utilization in neonatal intensive care unit (NICU) patients, infants 0-1 year not in the NICU, and children age 1-18 years (PED).

RESULTS

In the 48 hours after an index conventional or pathogen-reduced platelet transfusion, respectively, NICU patients received 1.0 ± 1.4 (n = 91 transfusions) compared with 1.2 ± 1.3 (n = 145) additional platelet doses (P = .29); infants 0-1 year not in the NICU received 2.8 ± 3.0 (n = 125) vs 2.6 ± 2.6 (n = 254) additional platelet doses (P = .57); and PEDs received 0.9 ± 1.6 (n = 644) vs 1.4 ± 2.2 (n = 673) additional doses (P < .001). Time to subsequent transfusion and red cell utilization were similar in every group (P > .05). The number and type of transfusion reactions did not significantly vary based on PLT type and no rashes were reported in NICU patients receiving phototherapy and pathogen-reduced PLTs.

CONCLUSIONS

Conventional and pathogen-reduced PLTs had similar utilization patterns in our pediatric populations. A small, but statistically significant, increase in transfusions was noted following pathogen-reduced PLT transfusion in PED patients, but not in other groups. Red cell utilization and transfusion reactions were similar for both products in all age groups.

The Millennium Villages Project: a retrospective, observational, endline evaluation

BACKGROUND

The Millennium Villages Project (MVP) was a 10 year, multisector, rural development project, initiated in 2005, operating across ten sites in ten sub-Saharan African countries to achieve the Millennium Development Goals (MDGs). In this study, we aimed to estimate the project's impact, target attainment, and on-site spending.

METHODS

In this endline evaluation of the MVP, we retrospectively selected comparison villages that best matched the project villages on possible confounding variables. Cross-sectional survey data on 40 outcomes of interest were collected from both the project and the comparison villages in 2015. Using these data, as well as on-site spending data collected during the project, we estimated project impacts as differences in outcomes between the project and comparison villages; target attainment as differences between project outcomes and prespecified targets; and on-site spending as expenditures reported by communities, donors, governments, and the project. Spending data were not collected in the comparison villages.

FINDINGS

Averaged across the ten project sites, we found that impact estimates for 30 of 40 outcomes were significant (95% uncertainty intervals [UIs] for these outcomes excluded zero) and favoured the project villages. In particular, substantial effects were seen in agriculture and health, in which some outcomes were roughly one SD better in the project villages than in the comparison villages. The project was estimated to have no significant impact on the consumption-based measures of poverty, but a significant favourable impact on an index of asset ownership. Impacts on nutrition and education outcomes were often inconclusive (95% UIs included zero). Averaging across outcomes within categories, the project had significant favourable impacts on agriculture, nutrition, education, child health, maternal health, HIV and malaria, and water and sanitation. A third of the targets were met in the project sites. Total on-site spending decreased from US$132 per person in the first half of the project (of which $66 was from the MVP) to $109 per person in the second half of the project (of which $25 was from the MVP).

INTERPRETATION

The MVP had favourable impacts on outcomes in all MDG areas, consistent with an integrated rural development approach. The greatest effects were in agriculture and health, suggesting support for the project's emphasis on agriculture and health systems strengthening. The project conclusively met one third of its targets.

FUNDING

The Open Society Foundations, the Islamic Development Bank, and the governments of Japan, South Korea, Mali, Senegal, and Uganda.

A Bioabsorbable Polymer for Collateral Ligament Repair in the Pig

A bioabsorbable internal fixation device of a poly-L-isomer of lactic acid (PLLA) was used to repair the proximal attachment of the medial femorotibial collateral ligament (MCL) in six miniature Yucatan pigs and compared with metal screw fixation in four pigs. Healing was evaluated by physical examination, gross dissection of surgical sites and histological evaluation of bone ligament interface. Chemical stress analysis of the tack was also evaluated.

The absorbable PLLA tack induced minimal tissue reaction and maintained sufficient apposition for healing of the MCL in the miniature Yucatan pigs. No postsurgical complications were noted in the experimental or control groups. All surgical implant procedures were considered successful in maintaining MCL apposition. This study suggests future potential for utilization of the PLLA tack for bioabsorbable implants in soft tissue or bone.

A bioabsorbable internal fixation device of a poly-L-isomer of lactic acid was used to repair the proximal attachment of the medial femorotibial collateral ligament in pigs, and compared with metal screw fixation. No postsurgical complications were noted in either group. All surgical implant procedures were successful. This study suggests future potential for utilization of the tack for bioabsorbable implants in soft tissue or bone.

Affimer proteins are versatile and renewable affinity reagents

Molecular recognition reagents are key tools for understanding biological processes and are used universally by scientists to study protein expression, localisation and interactions. Antibodies remain the most widely used of such reagents and many show excellent performance, although some are poorly characterised or have stability or batch variability issues, supporting the use of alternative binding proteins as complementary reagents for many applications. Here we report on the use of Affimer proteins as research reagents. We selected 12 diverse molecular targets for Affimer selection to exemplify their use in common molecular and cellular applications including the (a) selection against various target molecules; (b) modulation of protein function in vitro and in vivo; (c) labelling of tumour antigens in mouse models; and (d) use in affinity fluorescence and super-resolution microscopy. This work shows that Affimer proteins, as is the case for other alternative binding scaffolds, represent complementary affinity reagents to antibodies for various molecular and cell biology applications.

NG2 proteoglycan as a pericyte target for anticancer therapy by tumor vessel infarction with retargeted tissue factor

tTF-TAA and tTF-LTL are fusion proteins consisting of the extracellular domain of tissue factor (TF) and the peptides TAASGVRSMH and LTLRWVGLMS, respectively. These peptides represent ligands of NG2, a surface proteoglycan expressed on angiogenic pericytes and some tumor cells. Here we have expressed the model compound tTF-NGR, tTF-TAA, and tTF-LTL with different lengths in the TF domain in E. coli and used these fusion proteins for functional studies in anticancer therapy. We aimed to retarget TF to tumor vessels leading to tumor vessel infarction with two barriers of selectivity, a) the leaky endothelial lining in tumor vessels with the target NG2 being expressed on pericytes on the abluminal side of the endothelial cell barrier and b) the preferential expression of NG2 on angiogenic vessels such as in tumors. Chromatography-purified tTF-TAA showed identical Factor X (FX)-activating procoagulatory activity as the model compound tTF-NGR with Km values of approx. 0.15 nM in Michaelis-Menten kinetics. The procoagulatory activity of tTF-LTL varied with the chosen length of the TF part of the fusion protein. Flow cytometry revealed specific binding of tTF-TAA to NG2-expressing pericytes and tumor cells with low affinity and dissociation KD in the high nM range. In vivo and ex vivo fluorescence imaging of tumor xenograft-carrying animals and of the explanted tumors showed reduction of tumor blood flow upon tTF-TAA application. Therapeutic experiments showed a reproducible antitumor activity of tTF-TAA against NG2-expressing A549-tumor xenografts, however, with a rather small therapeutic window (active/toxic dose in mg/kg body weight).

Low-Energy Ultrasound Treatment Improves Regional Tumor Vessel Infarction by Retargeted Tissue Factor

OBJECTIVES

To enhance the regional antitumor activity of the vascular-targeting agent truncated tissue factor (tTF)-NGR by combining the therapy with low-energy ultrasound (US) treatment.

METHODS

For the in vitro US exposure of human umbilical vein endothelial cells (HUVECs), cells were put in the focus of a US transducer. For analysis of the US-induced phosphatidylserine (PS) surface concentration on HUVECs, flow cytometry was used. To demonstrate the differences in the procoagulatory efficacy of TF-derivative tTF-NGR on binding to HUVECs with a low versus high surface concentration of PS, we performed factor X activation assays. For low-energy US pretreatment, HT1080 fibrosarcoma xenotransplant-bearing nude mice were treated by tumor-regional US-mediated stimulation (ie, destruction) of microbubbles. The therapy cohorts received the tumor vessel-infarcting tTF-NGR protein with or without US pretreatment (5 minutes after US stimulation via intraperitoneal injection on 3 consecutive days).

RESULTS

Combination therapy experiments with xenotransplant-bearing nude mice significantly increased the antitumor activity of tTF-NGR by regional low-energy US destruction of vascular microbubbles in tumor vessels shortly before application of tTF-NGR (P < .05). Mechanistic studies proved the upregulation of anionic PS on the outer leaflet of the lipid bilayer of endothelial cell membranes by low-energy US and a consecutive higher potential of these preapoptotic endothelial cells to activate coagulation via tTF-NGR and coagulation factor X as being a basis for this synergistic activity.

CONCLUSIONS

Combining retargeted tTF to tumor vessels with proapoptotic stimuli for the tumor vascular endothelium increases the antitumor effects of tumor vascular infarction. Ultrasound treatment may thus be useful in this respect for regional tumor therapy.

Institutional deliveries weakly associated with improved neonatal survival in developing countries: evidence from 192 Demographic and Health Surveys

BACKGROUND

Child and maternal mortality remain high in many developing countries. A principal strategy used in low- and middle-income countries is increasing the proportion of pregnancies delivered at facilities. Although this strategy is reasonable with high quality facilities, evidence for the protective effects of facility deliveries is mixed.

METHODS

We pooled 1.47 million birth records collected by the Demographic and Health Surveys to estimate the association between institutional deliveries and early neonatal mortality. Subsample analysis and instrumental variable estimation were used to assess and correct the extent to which mortality differentials are biased by an increased likelihood of facility attendance for high-risk deliveries.

RESULTS

No associations between institutional deliveries and early neonatal mortality were found in the pooled sample [adjusted odds ratio (aOR) 0.995, 95% confidence interval (CI) 0.966-1.025)]. When stratified by facility type, protective effects were found for private facilities (aOR 0.876, 95% CI 0.840-0.914), but not for public hospitals or health centres. Significant protective effects were found when past behaviour was used to eliminate selection bias generated by short-term responses to medical need (aOR 0.884, 95% CI 0.814-0.961). At the community and country levels, strong positive associations were found between early neonatal mortality among facility deliveries and the prevalence of institutional deliveries.

CONCLUSION

Facility deliveries have the potential to reduce early neonatal mortality in developing countries. The results presented suggest that the quality, utilization and protective effects of institutional deliveries vary widely across countries; major improvements in both utilization and quality of care will be needed to achieve further improvements in maternal and child health.