Succinyl-CoA Ligase Deficiency in Pro-inflammatory and Tissue-Invasive T Cells

Autoimmune T cells in rheumatoid arthritis (RA) have a defect in mitochondrial oxygen consumption and ATP production. Here, we identified suppression of the GDP-forming β subunit of succinate-CoA ligase (SUCLG2) as an underlying abnormality. SUCLG2-deficient T cells reverted the tricarboxylic acid (TCA) cycle from the oxidative to the reductive direction, accumulated α-ketoglutarate, citrate, and acetyl-CoA (AcCoA), and differentiated into pro-inflammatory effector cells. In AcCoA^hi RA T cells, tubulin acetylation stabilized the microtubule cytoskeleton and positioned mitochondria in a perinuclear location, resulting in cellular polarization, uropod formation, T cell migration, and tissue invasion. In the tissue, SUCLG2-deficient T cells functioned as cytokine-producing effector cells and were hyperinflammatory, a defect correctable by replenishing the enzyme. Preventing T cell tubulin acetylation by tubulin acetyltransferase knockdown was sufficient to inhibit synovitis. These data link mitochondrial failure and AcCoA oversupply to autoimmune tissue inflammation.

Long-term outcomes and recurrence-free interval after the treatment of keloids with a standardized protocol

BACKGROUND

Recurrence rates of keloids have generally been reported at one time point. However, the longer the duration after treatment, the greater the likelihood that such lesions will recur. In this study, we analysed the time to recurrence during long-term follow-up.

MATERIAL AND METHODS

We retrospectively reviewed recurrence-free interval in 52 patients with keloid (age 8-79 years) who had been treated between June 2006 and January 2011 using a standardised protocol developed by our group.

RESULTS

Mean duration of follow-up was 37.5 (range, 7-120) months in patients with keloid. Kaplan-Meier survival curves revealed a statistically significant difference in recurrence-free interval between ear keloids and keloids excluding ear keloids. Recurrence rate for keloids was high in the first 2 years after treatment.

CONCLUSIONS

Kaplan-Meier analysis was useful for understanding the tendency of recurrence of keloids after treatment using a standardised protocol.

Effect of chest-compression-only bystander cardiopulmonary resuscitation on the likelihood of initial shockable rhythm after out-of-hospital cardiac arrest: a propensity matching analysis

Background/Introduction

Shockable rhythm after cardiac arrest is highly expected after early initiation of bystander cardiopulmonary resuscitation (CPR) owing to increased coronary perfusion. However, the relationship between bystander CPR and initial shockable rhythm in patients with out-of-hospital cardiac arrest (OHCA) remains unclear. We hypothesized that chest-compression-only CPR (CC-CPR) before emergency medical service (EMS) arrival has an equivalent effect on the likelihood of initial shockable rhythm to the standard CPR (chest compression plus rescue breathing [S-CPR]).

Purpose

We aimed to examine the rate of initial shockable rhythm and 1-month outcomes in patients who received bystander CPR after OHCA.

Methods

The study included 59,688 patients (age, ≥18 years) who received bystander CPR after an OHCA with a presumed cardiac origin witnessed by a layperson in a prospectively recorded Japanese nationwide Utstein-style database from 2013 to 2017. Patients who received public-access defibrillation before arrival of the EMS personnel were excluded. The patients were divided into CC-CPR (n=51,520) and S-CPR (n=8168) groups according to the type of bystander CPR received. The primary end point was initial shockable rhythm recorded by the EMS personnel just after arrival at the site. The secondary end point was the 1-month outcomes (survival and neurologically intact survival) after OHCA. In the statistical analyses, a Cox proportional hazards model was applied to reflect the different bystander CPR durations before/after propensity score (PS) matching.

Results

The crude rate of the initial shockable rhythm in the CC-CPR group (21.3%, 10,946/51,520) was significantly higher than that in the S-CPR group (17.6%, 1441/8168, p<0.0001) before PS matching. However, no significant difference in the rate of initial shockable rhythm was found between the 2 groups after PS matching (18.3% [1493/8168] vs 17.6% [1441/8168], p=0.30). In the Cox proportional hazards model, CC-CPR was more negatively associated with the initial shockable rhythm before PS matching (unadjusted hazards ratio [HR], 0.97; 95% confidence interval [CI], 0.94–0.99; p=0.012; adjusted HR, 0.92; 95% CI, 0.89–0.94; p<0.0001) than S-CPR. After PS matching, however, no significant difference was found between the 2 groups (adjusted HR of CC-CPR compared with S-CPR, 0.97; 95% CI, 0.94–1.00; p=0.09). No significant differences were found between C-CPR and S-CPR in the 1-month outcomes after PS matching as follows, respectively: survival, 8.5% and 10.1%; adjusted odds ratio, 0.89; 95% CI, 0.79–1.00; p=0.07; cerebral performance category 1 or 2, 5.5% and 6.9%; adjusted odds, 0.86; 95% CI, 0.74–1.00; p=0.052.

Conclusions

Compared with S-CPR, the CC-CPR before EMS arrival had an equivalent multivariable-adjusted association with the likelihood of initial shockable rhythm in the patients with OHCA due to presumed cardiac causes that was witnessed by a layperson.

Funding Acknowledgement

Type of funding source: None

Fluorescence optical imaging in patients with active rheumatoid arthritis: a comparison with ultrasound and an association with biomarkers

Objectives: This study compared indocyanine green (ICG)-enhanced fluorescence optical imaging (FOI) and musculoskeletal ultrasound (MSUS), and explored the significance of the FOI findings based on the association between the FOI and MSUS findings and serum biomarkers in patients with rheumatoid arthritis (RA). The study also explored the association between the FOI findings and patients' joint destruction at the joint-area level.Method: We enrolled 50 consecutive patients with active RA from among the patients hospitalized from May 2014 to March 2016 at Nagasaki University Hospital, Japan. FOI images were acquired with the Xiralite^® fluorescence imaging system and compared with the patients' clinical examination results and MSUS findings. On the same day, the patients' clinical disease activity and levels of serum biomarkers (including vascular endothelial growth factor) were obtained.Results: Although the FOI detected synovitis with high sensitivity, the frequency of positive findings and the diagnostic performance with MSUS as the reference standard for FOI differed considerably among the phases of FOI as well as among the affected joint regions. The FOI scores were positively correlated with clinical disease activity, MSUS scores, and serum biomarkers. The severity of FOI-proven synovitis was associated with the presence of MSUS-proven bone erosion.Conclusion: FOI is effective for detecting joint inflammation in RA patients, with high accuracy. The severity of the FOI score was closely associated with the joint destruction at the joint-area level. However, the significance of positive FOI findings differed depending on not only the phase of FOI but also the affected joint regions.

Predictive factors for effective selection of Interleukin-6 inhibitor and tumor necrosis factor inhibitor in the treatment of rheumatoid arthritis

Treatment of rheumatoid arthritis (RA) is aimed at long-term remission and inhibition of joint destruction by different biologic drugs. However, the choice of a particular biologic agent based on individual cases of RA remains unestablished. Interleukin-6 (IL-6) inhibitor and tumor necrosis factor (TNF) inhibitor are common biologics used for the treatment of RA. This study aimed to investigate predictive factors for effective selection of tocilizumab (IL-6 inhibitor) and etanercept (TNF inhibitor) in patients with RA. This is a retrospective cohort study. The 196 patients analyzed in this study were divided into four groups: tocilizumab treatment as the first biologic group (TCZ first, 42 patients), tocilizumab as second/ third biologic group (TCZ second, 34 patients), etanercept as the first biologic group (ETN first, 103 patients) and etanercept as second/third group (ETN second, 17 patients). Visual analog scale (VAS), clinical disease activity index (CDAI), and modified health assessment questionnaire (mHAQ) scores at the initiation of biologic treatment and after 6 months of tocilizumab and etanercept therapy were measured and compared to clinical parameters and radiographical parameters among the four groups. CRP, MMP-3, VAS, CDAI, and HAQ were improved after 6 months of treatment in all groups. Improvement of clinical outcomes was correlated with CRP value, duration of RA, and Sharp scores at the initiation of treatment. Multivariate analysis demonstrated improvement in CDAI was significantly associated with the yearly progression of erosion according to the Sharp score in TCZ first group (OR, 1.5; 95% CI, 1.03–2.07) and was negatively associated with the duration of RA (OR, 0.49; 95% CI, 0.29–0.86) at the initiation of treatment with ETN first group. We identified the predictive factors for effective selection of tocilizumab and etanercept treatment and established the effectiveness of tocilizumab for the patients with rapid progressive joint erosion and etanercept for the early administration from diagnosis of RA.

Effects of cigarette smoking and human T-cell leukaemia virus type 1 infection on anti-citrullinated peptide antibody production in Japanese community-dwelling adults: the Nagasaki Islands Study

Objectives: We investigated whether the positivity of anti-citrullinated peptide antibody (ACPA) is associated with cigarette-smoking status and human T-cell leukaemia virus type 1 (HTLV-1) infection in a general population in Nagasaki, Japan, which is an ageing and HTLV-1-endemic area.Method: Baseline data from community-dwelling people in the Nagasaki Islands Study (NaIS) were included in this cross-sectional analysis. ACPA and HTLV-1 were measured in 3887 subjects without a history of treatment for rheumatoid arthritis. A logistic regression analysis was performed to assess the relationship between ACPA positivity and candidates of correlation with ACPA, i.e. the cigarette-smoking status quantified by Brinkman's index (BI) and HTLV-1 positivity.Results: Fifty-one subjects (1.3%) showed ACPA positivity, and 650 subjects (16.6%) were HTLV-1 carriers. In an age- and gender-adjusted logistic regression analysis, the BI [odds ratio (OR) 1.09, 95% confidence interval (CI)1.02-1.14, p = 0.0031] and a BI value > 500 (OR 3.92, 95% CI 1.72-9.22, p = 0.0014) were each significantly associated with ACPA positivity. HTLV-1 positivity did not show any association with ACPA positivity.Conclusion: A significant effect of cigarette-smoking status on ACPA production was revealed, whereas HTLV-1 positivity was not associated with ACPA production in this general population.

AB0089 THE ANALYSIS FOR THE INHIBITION OF ANGIOGENESIS BY JAK INHIBITOR

Background:

Many blood vessels are generated in the hyperplastic synovial tissue of patients with rheumatoid arthritis (RA), and lead to chronic tissue inflammation and joint destruction [1]. Janus kinase (JAK) family consisting of JAK1, JAK2, JAK3 and tyrosine kinase 2 (TYK2) are chain receptors which phosphorylate signal transducers and activators of transcription (STAT) and mediate inflammatory diseases including RA [2]. Nowadays, several JAK inhibitors such as Tofacitinib (TOF), Baricitinib (BAR) and Peficitinib (PEF) have been developed and demonstrated to have the inhibitory effects on inflammatory arthritis [3-5]. However, there were few reports concerning their effects on angiogenesis in vitro.

Objectives:

The purpose of the present study is to investigate the influence of JAK inhibitors on angiogenesis of human umbilical vein endothelial cell (HUVEC) activated by vascular endothelial growth factor (VEGF).

Methods:

The cell line of HUVECs were used for this study. The activity of proliferation and tube formation were analyzed by counting assay and tube formation assay, respectively.

In counting assay, HUVECs (5 × 104cells/ml) were seeded onto 96-well cell culture plate with 20 ng/ml VEGF including various doses (0.1µM, 1µM, 5µM) of TOF, BAR or PEF. After 48 hours incubation at 37°C in a humidified atmosphere containing 5% CO2, cell proliferation of each groups was assessed using cell counting kit. In tube formation assay, HUVECs (5 × 104cells/ml) were treated with 20ng/ml VEGF including various dose (0.1µM, 1µM, 5µM) of TOF, BAR or PEF for 00 hours, then seeded onto 48-well plate applied with Matrigel. After 24 hours incubation on Matrigel, the capillary-like tube formation of each well was photographed using phase contrast microscopy. Tube formation were quantitated by measurement of the length of branch.

Results:

HUVECs were activated in proliferation and tube formation by VEGF treatment. And, the proliferation and tube formation of HUVECs activated by VEGF were suppressed by All of TOF, BAR and PEF. In particular, TOF and PEF could suppress them highly.

Conclusion:

This study showed the inhibitory effect of JAK inhibitors on proliferation and tube formation of HUVECs activated by VEGF. In particular, the angiogenesis of HUVECs activated by VEGF was highly suppressed by TOF and PEF. VEGF is reported to regulate the angiogenesis through multi JAK-STAT signaling pathways [6]. The inhibitory effects on angiogenesis of TOF, BAR and PEF might depend on the differences in their affinity for JAKs. VEGF has been shown to a have a central involvement in the angiogenic process in RA [7]. JAK inhibitors might suppress the angiogenesis in RA synovial tissues by inhibiting VEGF signaling.

References:

[1]Scott DL, et al. Rheumatoid arthritis. Lancet. 2010.

[2]Banerjee S, et al. JAK-STAT signaling as a target for inflammatory and autoimmune diseases: current and future prospects. Drugs. 2017.

[3]William D, et al. JAK inhibitors in dermatology: the promise of a new drug class. Journal of the American Academy of Dermatology. 2017.

[4]Dhillon S. Tofacitinib: A Review in Rheumatoid Arthritis. Drugs. 2017.

[5]Markham A, et al. Peficitinib: First Global Approval. Drugs. 2019.

[6]Zhang HY, et al. Three important components in the regeneration of the cavernous nerve: brain-derived neurotrophic factor, vascular endothelial growth factor and the JAK/STAT signaling pathway. Asian journal of andrology. 2011.

[7]Paleolog EM. Angiogenesis in rheumatoid arthritis. Arthritis research. 2002.

Acknowledgments:

none

Disclosure of Interests:

None declared

AB1232 ORAL DYSBIOSIS REFLECTS THE IMMUNOLOGICAL ALTERATION OF RA REGARDING TO ACPA AND HLA DRB1*SE: NAGASAKI ISLAND STUDY

Background:

Anti-citrullinated protein antibody (ACPA) production is observed in several organs even prior to the onset of rheumatoid arthritis (RA), and oral mucosa is considered to be one of the important tissues. The presence of HLA-DRB1*SE closely associates with ACPA production. Saliva is considered to reflect the oral microbiota including periodontal disease. Alteration of oral microbiota of RA becomes to be normalized by DMARDs treatment, however, the interaction of HLA-DRB1*SE, ACPA and oral microbiota of RA patients remains to be elucidated.

Objectives:

The Nagasaki Island Study, which had started in 2014 collaborating with Goto City, is intended for research of the preclinical stage of RA, including ACPA/HLA genotype screening and ultrasound and magnetic resonance imaging examinations in high-risk subjects. Using the samples accumulated in this cohort, we have tried to investigate the difference of oral microbiota among RA patients and healthy subjects regarding to ACPA and HLA-DRB1*SE.

Methods:

Blood and salivary samples were obtained from 1422 subjects out of 4276 who have participated in the Nagasaki Island Study from 2016 to 2018. ACPA positivity was 1.7 % in total. Some of RA patients resided in Goto City participated in the Nagasaki Island Study. At this point, we selected 291 subjects, who were ACPA positive non-RA healthy subjects (n=22) and patients with RA (n=33, 11 subjects were ACPA positive and 22 ACPA negative respectively) as the case, age and gender matched ACPA negative non-RA healthy subjects (n=236) as the control. ACPA was measured by an enzyme-linked immunosorbent assay, and HLA genotyping was quantified by next-generation sequencing (Ref.1). The operational taxonomic unit (OUT) analysis using 16S rRNA gene sequencing were performed. The richness of microbial diversity within-subject (alpha diversity) was scaled via Shannon entropy. The dissimilarity between microbial community composition was calculated using Bray-Curtis distance as a scale, and differences between groups (beta diversity) were tested by permutational multivariate analysis of variance (PERMANOVA). In addition, UniFrac distance calculated in consideration of the distance on the phylogenetic tree were performed.

Results:

Median age 70 y.o., % Female 58.8 %. Among RA and non-RA subjects, not alpha diversity but beta diversity was statistically significance (p=0.022, small in RA). In RA subjects, both alpha and beta diversity is small (p<0.0001), especially significant in ACPA positive RA (Figure 1). Amongt RA subjects, presence of HLA-DRB1*SE did not show the difference but the tendency of being small of alpha diversity (p=0.29).

Conclusion:

Our study has suggested for the first time the association of oral microbiota alteration with the presence of ACPA and HLA-DRB1*SE. Oral dysbiosis may reflect the immunological status of patients with RA.

References:

[1]Kawaguchi S, et al. Methods Mol Biol 2018;1802: 22

Disclosure of Interests:

None declared

P492Estimation of no-flow duration and survival in patients with an initial shockable rhythm after out-of-hospital cardiac arrest

Funding Acknowledgements

Japan Society for the Promotion of Science (KAKENHI Grant No. 18K09999)

Background

In patients with unwitnessed out-of-hospital cardiac arrest (OHCA), the actual no-flow duration (the time with no organ perfusion) is unclear. However, when these patients have a shockable rhythm as an initial recorded rhythm, the no-flow duration may be relatively short as compared with other initial rhythms, and some patients can obtain a good functional outcome after OHCA.

Purpose

The purpose of the present study was to estimate the no-flow duration and to determine the relationship between no-flow duration and neurologically intact survival in patients with an initial shockable rhythm after OHCA.

Methods

We reviewed 82,464 patients with OHCA (aged ≥18 years, non-traumatic, witnessed, and without any bystander interventions) who were included in the All-Japan Utstein-style registry from 2013 to 2017. The study end point was 1-month neurologically intact survival (Cerebral Performance Category scale 1 or 2). No-flow duration was defined as the time from emergency call to emergency medical services (EMS) arrival at the patient site.

Results

The rate of 1-month neurologically intact survival in the patients with an initial shockable rhythm (n = 10,384, 12.6% of overall patients) was 16.5% (1718/10,384). No-flow duration was significantly and inversely associated with 1-month neurologically intact survival (adjusted odds ratios for 1-minute increments: 0.85, 95% confidence interval: 0.84–0.86). The proportion of patients with a shockable rhythm to the overall patients (y, %) had a high correlational relationship with no-flow duration (x, min), depicted by y = 21.0 - 0.95 × x, R² = 0.935. In this analytical model, the number of patients with shockable rhythm reached null at 22 minutes of no-flow duration. The no-flow durations, beyond which the chance for initial shockable rhythm diminished to &lt;10%, &lt;5%, and &lt;1%, were 12, 13, and 17 minutes, respectively. The rate of neurologically intact survival in the patients with shockable rhythm (y, %) and no-flow duration (x, min) were also found to have a strong correlation, depicted by y = 0.16 × x² - 5.12 × x + 45.0, R² = 0.907. The no-flow durations, beyond which the chance for 1-month neurologically intact survival diminished to &lt;10%, &lt;5%, and &lt;1%, were 10, 11, and 15 minutes, respectively.

Conclusions

In OHCA patients without any bystander interventions before EMS personnel arrival, when a shockable rhythm is recorded by EMS personnel as an initial rhythm, the no-flow duration after cardiac arrest is highly likely to be &lt;17 minutes regardless of the layperson witness status. The limitation of no-flow duration to obtain a 1-month neurologically intact survival after OHCA may be 15 minutes when the patients have an initial shockable rhythm.

P498External validation of a field termination-of-resuscitation rule for refractory out-of-hospital cardiac arrests in Japan

Background

A universal basic life support termination-of-resuscitation (BLS-TOR) rule was developed to identify patients with out-of-hospital cardiac arrest (OHCA) eligible for field termination of cardiopulmonary resuscitation (CPR). In Japan, however, emergency medical service (EMS) providers are not allowed field termination of CPR and must transport all patients with OHCA to hospitals, regardless of return of spontaneous circulation (ROSC). Therefore, we previously developed a Japanese TOR (JP-TOR) rule in the field for refractory OHCAs using data from the All-Japan Utstein registry between 2011 and 2015, when CPR was performed according to the 2010 guidelines. The JP-TOR rule recommends CPR termination when patients meet all the following criteria: initial asystole, unwitnessed arrest, age ≥81 years, no bystander interventions before EMS arrival, and no ROSC after EMS-initiated CPR for 14 min.

Purpose

To validate the JP-TOR rule using more recent data where CPR was performed according to the 2015 guidelines, comparing the relevance of JP-TOR rule with the BLS-TOR rule, which consists of the following criteria: no prehospital ROSC after 6-min EMS-initiated CPR, arrest unwitnessed by EMS providers, and no shock received.

Methods

We analysed the records of 242,184 patients (age ≥18 years) who experienced OHCA treated by EMS providers. Data were obtained from a prospectively recorded Japanese nationwide Utstein-style database from 2016 to 2017. The primary endpoints were specificity and positive predictive value (PPV) for predicting the 1-month mortality after OHCA with the JP-TOR and BLS-TOR rules.

Results

The overall 1-month survival rate was 5.3% (12,847/242,184). The proportions of patients with OHCA fulfilled the JP-TOR and BLS-TOR criteria were 10.4% and 89.3%, respectively. The specificity and PPV of the JP-TOR and BLS-TOR rules for predicting 1-month mortality were 99.5% (95% confidence interval [CI], 99.4%–99.5%) and 99.8% (95% CI, 99.7%–99.8%) and 44.7% (95% CI, 43.8%–45.5%) and 96.7% (95% CI, 96.6%–96.8%), respectively.

Conclusions

The JP-TOR rule for EMS providers treating patients with OHCA in the field was successfully validated using more recent data from a Japanese registry where CPR was performed according to the 2015 guidelines. The JP-TOR rule was superior to the BLS-TOR rule in Japanese EMS systems, having both high specificity and PPV of &gt;99% for predicting 1-month mortality. The JP-TOR rule may help EMS providers decide whether to terminate resuscitation efforts for unresuscitable patients with OHCA in the field. Prospective validation studies and establishment of prehospital EMS protocol are required before implementing this rule in Japan.

P489Survival in children with out-of-hospital cardiac arrest after standard or chest compression-only bystander cardiopulmonary resuscitation before emergency medical services arrival

Funding Acknowledgements

Japan Society for the Promotion of Science (KAKENHI Grant No. 18K09999)

Background

For out-of-hospital cardiac arrest (OHCA), current cardiopulmonary resuscitation (CPR) guidelines recommend chest compression-only bystander CPR (C- BCPR) for both untrained and trained bystanders unwilling to perform rescue breaths before emergency medical services personnel arrival. However, during 3 consecutive guideline periods, changes in type of BCPR and neurologically intact survival rate are unclear in paediatric OHCA cases.

Purpose

We aimed to determine the change in the rate and type of BCPR in correlation to the 1-month neurologically intact survival and causes of OHCA.

Methods

We reviewed 5461 children with bystander witnessed OHCA included in the All-Japan Utstein-style registry from 2005 to 2017. Patients were divided into 3 groups according to the type of BCPR: no BCPR (NO-BCPR), standard BCPR with rescue breaths (S-BCPR), and C-BCPR. Guideline periods 2005 to 2010 (pre-G2010), 2011 to 2015 (G2010), and 2016 to 2017 (G2015) were used for comparison over time. The study endpoint was 1-month neurologically intact survival (Cerebral Performance Category [CPC] scale 1 or 2; CPC 1–2).

Results

The rates of patients receiving any BCPR and 1-month CPC 1–2 by year significantly increased from 46.2% and 9.4% in 2005 to 61.3% and 15.7% in 2017 (all P for trend &lt;0.0001), respectively. The rates of patients receiving C-BCPR in the pre-G2010 period significantly increased from 21.6% to 35.5% in the G2010 period, and to 40.4% in the G2015 period (P for trend &lt;0.0001); the overall proportion of cases with 1-month CPC 1–2 increased from 9.1% to 10.8% and 14.7%, respectively (P for trend &lt;0.0001). Particularly, in patients receiving C-BCPR, CPC 1–2 rate significantly increased from 9.5% in the pre-G2010 period to 19.0% in the G2015 period (P for trend &lt;0.0001). For all time periods, 1-month CPC 1–2 rate in the S-BCPR (17.2%) cohort was significantly higher than those in the C-BCPR (12.5%) and NO-BCPR (6.4%) cohorts (adjusted odds ratio [aOR] of S-BCPR compared with C-BCPR, 1.59; 95% confidence interval [CI], 1.25–2.01; P &lt; 0.0001; compared with NO-BCPR, aOR 2.31; 95% CI, 1.82–2.94; P &lt; 0.0001). No significant difference between S-BCPR and C-BCPR was found in 1-month CPC 1–2 rate for patients with non-traumatic origin (17.7% vs. 16.3%; aOR, 1.23, 95% CI, 0.95–1.59, all P &gt;0.05). However, in patients with traumatic origin, S-BCPR was superior to C-BCPR (15.1% vs. 3.4%; aOR, 4.53, 95% CI, 2.39–8.61, all P &lt;0.0001). During the 3 guidelines periods, the CPC 1–2 rate in patients with non-traumatic origin significantly increased from 11.8% to 19.7% (P for trend &lt; 0.0001), but not in patients with traumatic origin (from 4.9% to 4.1%, P for trend = 0.29).

Conclusions

During the 3 guidelines periods, the rate of C-BCPR and 1-month CPC 1–2 increased by approximately 2-fold each over time. C-BCPR was associated with increased odds of 1-month CPC 1–2 similar to S-BCPR for children with non-traumatic origin but not in those with traumatic origin.

AB0090 DEATH RECEPTOR 3 REGULATES THE GENE EXPRESSIONS OF VARIOUS KEY MOLECULES IN RHEUMATOID SYNOVIAL FIBROBLASTS

Background:

Rheumatoid arthritis (RA) is a chronic inflammatory disease that causes hyperplasia of synovial tissue. Death receptor 3 (DR3) is a tumor necrosis factor receptor and binds to TL1A, a member of the TNF family. DR3 is involved in the mechanism of cell proliferation and apoptosis through NF-κB signaling. Suppression of DR3 in rheumatoid synovial fibroblasts (RA-FLS) is associated with hyperplasia of rheumatoid synovial tissue [1]. We previously revealed the expression profiles regulated by TL1A, suggesting that TL1A might affect the pathogenesis of RA, including proliferation, regulation of B cells and T cells, inflammation, and cytokine processing [2].

Objectives:

In this study, we investigated the gene expression profiles regulated by DR3 in RA-FLS to reveal how DR3 is involved in the pathogenesis of RA.

Methods:

RA-FLS were from patients with RA. Four individual lines of primary cultured RA-FLS were incubated either with 1000 ng/ml of human DR3-Fc protein or 1000ng/ml of human IgG1 as a control for 12h. Gene expressions were detected by microarray assay.

Results:

Microarray data analysis revealed that DR3 up-regulated or down-regulated the expression of various genes in RA-FLS (Figure). The function of regulated genes included protein-L-isoaspartate (D-aspartate) O-methyltransferase activity, carboxyl-O-methyltransferase activity, protein carboxyl O-methyltransferase activity, regulation of cilium assembly, O-methyltransferase activity, regulation of plasma membrane bounded cell projection assembly, regulation of cell projection assembly, regulation of organelle assembly, protein methyltransferase activity, and S-adenosylmethionine-dependent methyltransferase activity. The most up-regulated 2 genes by DR3 were KIAA1109 (KIAA1109), and adhesion G protein-coupled receptor A3 (ADGRA3). The most down-regulated 2 genes by DR3 were RNA exonuclease 2 (REXO2), and family with sequence similarity 120A (FAM120A).

Conclusion:

In this study, we first revealed the expression profiles of genes regulated by DR3 in RA-FLS. KIAA1109/TENR/IL2/IL21 gene is strongly associated with RA in European descent populations [3]. ADGRA3 is a member of G protein-coupled receptors (GPCRs). GPCRs associates with the regulation of cytoskeletal organization, the cell adhesion and migration, cell proliferation and apoptosis, and cell differentiation [4]. Loss of REXO2 affects cell growth and morphology [5], and REXO2 was identified as a target gene for inflammatory bowel disease-associated variants [6]. FAM120A regulates activity of Src kinase to protect cells from oxidative stress-induced apoptosis [7]. DR3 regulates the gene expressions of various key molecules in RA-FLS and may affect the pathogenesis of RA by regulating gene expression of RA-FLS.

References:

[1]Takami N. et al., Arthritis Rheuma. 2006;54:779-787.

[2]Fukuda K. et al., Biomed Rep. 2019;1:1-5.

[3]Teixeira VH. et al., Arthritis Research & Therapy. 2009;11:R45.

[4]Hamann J. et al., Pharmacol Rev. 2015;67:338-367.

[5]Bruni F, et al., PLoS One. 2013;8:e64670.

[6]Hulur I, et al., BMC Genomics. 2015;16:138.

[7]Tanaka M. et al., Mol Cell Biol. 2009;29:402-413.

Disclosure of Interests:

None declared

P490Time boundaries of three-phase time-sensitive model for ventricular fibrillation cardiac arrest

Funding Acknowledgements

Japan Society for the Promotion of Science (KAKENHI Grant No. 18K09999)

Background

Recent clinical evidence has suggested that the pathophysiology of ventricular fibrillation (VF) cardiac arrest may consist of three time-sensitive phases, namely electrical, circulatory, and metabolic. According to this model of cardiopulmonary resuscitation (CPR), the optimal treatment of cardiac arrest is phase-specific. The potential survival benefit of bystander cardiopulmonary resuscitation (BCPR) depends in part on ischemic time (i.e., the collapse-to-shock interval), with the greatest benefit occurring during the circulatory (second) phase. However, the time boundaries between phases are not precisely defined in the current literature.

Purpose

The purpose of the present study was to determine the time boundaries of the three-phase time-sensitive model for VF cardiac arrest.

Methods

We reviewed 20,741 adult patients with initial VF after witnessed out-of-hospital cardiac arrest from a presumed cardiac origin who were included in the All-Japan Utstein-style registry from 2013 to 2017. We excluded patients who underwent bystander defibrillation prior to arrival of emergency medical services personnel. The study end point was 1-month neurologically intact survival (Cerebral Performance Category scale 1 or 2). Collapse-to-shock interval was defined as the time from collapse to first shock delivery by emergency medical services personnel. Patients were divided into two groups, BCPR (n = 11,606, 56.0%) and non-BCPR (n = 9135, 44.0%), according to whether they had received BCPR or not.

Results

The rate of 1-month neurologically intact survival in the BCPR group was significantly higher than that in the non-BCPR group (27.9% [3237/11,606] vs 17.9% [1632/9135], P &lt; 0.0001; adjusted odds ratio [OR], 1.90; 95% confidence interval [CI], 1.75–2.07; P &lt; 0.0001). Overall, increased collapse-to-shock interval was associated with significantly decreased adjusted odds of 1-month neurologically intact survival (adjusted OR for each 1-minute increase, 0.94; 95% CI, 0.93–0.95; P &lt; 0.0001). In the BCPR group, the ranges of collapse-to-shock interval that were associated with increased adjusted 1-month neurologically intact survival were from 7 minutes (adjusted OR, 1.95; 95% CI, 1.44–2.63; P &lt; 0.0001) to 17 minutes (adjusted OR, 2.82; 95% CI, 1.62–4.91; P = 0.0002) as compared with those in the non-BCPR group. However, the increase in neurologically intact survival of the BCPR group became statistically insignificant as compared with that of the non-BCPR group when the collapse-to-shock interval was outside these ranges.

Conclusions

The above-mentioned findings suggest that the time boundaries of the three-phase time-sensitive model for VF cardiac arrest may be as follows: electrical phase, from collapse to &lt;7 minutes; circulatory phase, from 7 to 17 minutes; and metabolic phase, &gt;17 minutes onward from collapse.

The efficacy of eribulin mesylate for patients with cutaneous angiosarcoma previously treated with taxane: a multicentre prospective observational study

BACKGROUND

Taxanes are the current first-line treatment for advanced cutaneous angiosarcoma (CAS) for patients who are considered difficult to treat with doxorubicin owing to advanced age or comorbidity. However, no effective second-line therapy for such patients has been established.

METHODS

We designed a single-arm prospective observational study of eribulin mesylate (ERB) administered at a dose of 1·4 mg m^-2 on days 1 and 8 in a 21-day cycle. Patients with advanced CAS who were previously treated with a taxane and were scheduled to begin ERB treatment were enrolled. The primary endpoint was overall survival (OS) and the secondary endpoints were response rate (RR), progression-free survival (PFS) and toxicity assessment.

RESULTS

We enrolled a total of 25 patients. The median OS and PFS were 8·6 months and 3·0 months, respectively. The best overall RR was 20% (five of 25). In total, 16 grade 3/4 severe adverse events (SAEs) occurred; however, all patients recovered. Patients who achieved partial response or stable disease as best response had longer OS than those with progressive disease (median OS not reached and 3·3 months, respectively; P < 0·001). Patients who did not experience SAEs showed longer OS than those who did (median OS 18·8 months and 7·5 months, respectively; P < 0·05). Patients with distant metastasis had shorter median OS than those with locoregional disease, but without statistically significant difference.

CONCLUSIONS

ERB showed a promising RR and is a potential candidate for second-line treatment for patients with CAS, after treatment with taxanes. However, owing to the occurrence of SAEs in over half of the participants, caution should be exercised regarding ERB use in elderly patients. What is already known about this topic? Taxanes are the current first-line treatment for patients with advanced cutaneous angiosarcoma (CAS) who are considered difficult to treat with doxorubicin owing to advanced age or comorbidity. No effective therapy for taxane-resistant CAS has been established thus far. Eribulin suppresses microtubule polymerization and elicits an antitumour effect similar to that of taxanes. What does this study add? In our single-arm prospective observational study to evaluate the efficacy of eribulin for treating patients with advanced CAS who previously received taxanes, the median overall survival and progression-free survival were 8·6 and 3·0 months, respectively. Response rates at weeks 7, 13 and 25 were 20%, 17% and 14%, respectively. Although 16 grade 3/4 severe adverse events occurred, all patients recovered. Eribulin showed a promising response rate and is a potential candidate for second-line treatment in CAS after taxane treatment. Linked Comment: Smrke and Benson. Br J Dermatol 2020; 183:797-798.

Evaluation of a high-speed but low-throughput RT-qPCR system for detection of SARS-CoV-2

With the emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), a high-speed and convenient detection technology should be at the forefront of medical care worldwide. This study evaluated the usefulness of GeneSoC, a compact, high-speed reciprocal flow quantitative reverse transcription polymerase chain reaction system, for the detection of SARS-CoV-2. The results support the use of this system for the rapid identification of SARS-CoV-2. This approach can contribute to the strategic selection of initial management strategies for patients with COVID-19.

Complement profile in microscopic polyangiitis and granulomatosis with polyangiitis: analysis using sera from a nationwide prospective cohort study

OBJECTIVE

The complement cascade, especially the alternative pathway of complement, has been shown in basic research to be associated with anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV). We aimed to elucidate relationships between serum complement components and clinical characteristics in AAV.

METHOD

In a nationwide prospective cohort study (RemIT-JAV-RPGN), we measured the serum levels of C1q, C2, C3, C3b/iC3b, C4, C4b, C5, C5a, C9, factor B, factor D, factor H, factor I, mannose-binding lectin, and properdin in 52 patients with microscopic polyangiitis (MPA) and 39 patients with granulomatosis with polyangiitis (GPA).

RESULTS

The properdin level of MPA and GPA was significantly lower than that of healthy donors. The properdin level was negatively correlated with the Birmingham Vasculitis Activity Score (BVAS) (ρ = -0.2148, p = 0.0409). The factor D level at 6 months was significantly positively correlated with the Vasculitis Damage Index (VDI) at 6, 12, and 24 months (ρ = 0.4207, 0.4132, and 0.3115, respectively). Patients with a higher ratio of C5a to C5 had higher neutrophil percentage and serum immunoglobulin G levels, and significantly lower creatinine levels. Cluster analysis divided the MPA and GPA patients into three subgroups. A principal component (PC) analysis aggregated 15 types of complements into alternative pathway-related PC 1 and complement classical pathway and common pathway-related PC 2.

CONCLUSIONS

The serum levels of properdin and factor D were correlated with the BVAS and the VDI in MPA and GPA, respectively. Our analyses suggested the pathological heterogeneity of MPA and GPA from the aspect of complement components.

M2 Phenotype Macrophages Colocalize with Schwann Cells in Human Dental Pulp

Macrophages are immune cells with high plasticity that perform many functions related to tissue injury and repair. They are generally categorized as 2 functional phenotypes: M1 (proinflammatory) and M2 (anti-inflammatory and prohealing). To investigate the role of macrophages in human dental pulp, we examined the localization and distributional alterations of macrophages in healthy dental pulp as well as during the reparative process of pulp capping with mineral trioxide aggregate (MTA) and in cariously inflamed pulp of adult human teeth. We also quantified the populations of M1/M2 macrophages in healthy dental pulp by flow cytometric analysis. CD68⁺CD86⁺ cells (M1 phenotype) and CD68⁺CD163⁺ cells (M2 phenotype) were 2.11% ± 0.50% and 44.99% ± 2.22%, respectively, of 2.96% ± 0.41% CD68⁺ cells (pan-macrophages) in whole healthy dental pulp. Interestingly, M2 phenotype macrophages were associated with Schwann cells in healthy pulp, during mineralized bridge formation, and in pulp with carious infections in vivo. Furthermore, the M2 macrophages associated with Schwann cells expressed brain-derived neurotrophic factor (BDNF) under all in vivo conditions. Moreover, we found that plasma cells expressed BDNF. Coculture of Schwann cells isolated from human dental pulp and human monocytic cell line THP-1 showed that Schwann cells induced M2 phenotypic polarization of THP-1 cell-derived macrophages. The THP-1 macrophages that maintained contact with Schwann cells were stimulated, leading to elongation of their cell shape and expression of M2 phenotype marker CD163 in cocultures. In summary, we revealed the spatiotemporal localization of macrophages and potent induction of the M2 phenotype by Schwann cells in human dental pulp. M2 macrophages protect neural elements, whereas M1 cells promote neuronal destruction. Therefore, suppressing the neurodestructive M1 phenotype and maintaining the neuroprotective M2 phenotype of macrophages by Schwann cells may be critical for development of effective treatment strategies to maintain the viability of highly innervated dental pulp.

MMP (Matrix Metalloprotease)-9-Producing Monocytes Enable T Cells to Invade the Vessel Wall and Cause Vasculitis

RATIONALE

Giant cell arteritis (GCA)-a primary vasculitis of medium and large arteries-is associated with vessel wall damage, elastic membrane fragmentation, and vascular remodeling. Proteinases are believed to contribute to pathogenesis by degrading extracellular matrix and causing tissue injury.

OBJECTIVE

The MMP (matrix metalloproteinase)-9-a type IV collagenase-is produced in the vasculitic lesions of GCA. It is unknown which pathogenic processes are MMP-9 dependent.

METHODS AND RESULTS

The tissue transcriptome of GCA-affected temporal arteries contained high amounts of MMP-9 transcripts, and immunostaining for pro-MMP-9 localized the enzyme to wall-infiltrating macrophages. MMP-2 and MMP-9 transcripts were also abundant in monocytes and monocyte-derived macrophages from patients with GCA. Patient-derived monocytes outperformed healthy monocytes in passing through engineered basement membranes. GCA CD (cluster of differentiation) 4⁺ T cells required MMP-9-producing monocytes to penetrate through matrix built from type IV collagen. In vivo functions of MMP-9 were tested in a human artery-SCID (severe combined immunodeficiency) chimera model by blocking enzyme activity with a highly specific monoclonal antibody or by injecting rMMP-9 (recombinant MMP-9). Inhibiting MMP-9 activity profoundly suppressed vascular injury, decreased the density of inflammatory infiltrates ( P<0.001), reduced intramural neoangiogenesis ( P<0.001), and prevented intimal layer hyperplasia ( P<0.001). rMMP-9 amplified all domains of vasculitic activity, promoted assembly of T-cell infiltrates ( P<0.05), intensified formation of new microvessels ( P<0.001), and worsened intimal thickening ( P<0.001). Systemic delivery of N-acetyl-proline-glycine-proline-a matrikine produced by MMP-9-mediated gelatinolysis-had limited vasculitogenic effects.

CONCLUSIONS

In large vessel vasculitis, MMP-9 controls the access of monocytes and T cells to the vascular wall. T cells depend on MMP-9-producing monocytes to pass through collagen IV-containing basement membrane. Invasion of vasculitogenic T cells and monocytes, formation of neoangiogenic networks, and neointimal growth all require the enzymatic activity of MMP-9, identifying this protease as a potential therapeutic target to restore the immunoprivilege of the arterial wall in large vessel vasculitis.

P1703Impact of prehospital epinephrine administration and quality of cardiopulmonary resuscitation on neurologically intact survival in out-of-hospital cardiac arrest patients with non-shockable rhythm

Background

The effects of prehospital epinephrine administration in combination with the quality of cardiopulmonary resuscitation (CPR) on neurological outcomes in out-of-hospital cardiac arrest (OHCA) patients with non-shockable rhythm remains unclear.

Purpose

This study aimed to elucidate the effects of prehospital epinephrine administration in combination with the quality of CPR on neurologically intact survival in OHCA patients with non-shockable rhythm.

Methods

We analysed 118,732 adult OHCA patients with non-shockable rhythm from the All-Japan OHCA registry between 2011 and 2016 (29,989 emergency medical service [EMS]-witnessed arrests with EMS-initiated CPR [high-quality CPR] and 88,743 bystander-witnessed arrests with bystander-initiated CPR continued by EMS providers [low-quality CPR]). Patients who achieved prehospital return of spontaneous circulation without prehospital epinephrine administration were excluded. The primary outcome measure was 1-month neurologically intact survival (cerebral performance category 1 or 2; CPC 1–2). Time from collapse to prehospital epinephrine administration for patients with prehospital epinephrine administration, or to hospital arrival for patients without prehospital epinephrine administration was calculated and adjusted collectively in multivariate logistic regression analysis for 1-month CPC 1–2.

Results

Multivariate logistic regression analysis revealed that the time from collapse to prehospital epinephrine administration or to hospital arrival was negatively associated with 1-month CPC 1–2 (adjusted odds ratio [OR] 0.95 per 1-minute increment, 95% confidence interval [CI] 0.94–0.96). Compared with bystander-witnessed arrests without prehospital epinephrine administration, EMS-witnessed arrests with or without prehospital epinephrine administration were significantly associated with increased chances of 1-month CPC 1–2 (adjusted OR 2.04, 95% CI 1.50–2.75 and adjusted OR 1.97, 95% CI 1.57–2.48, respectively). Prehospital epinephrine administration was significantly associated with an increased chance of 1-month CPC 1–2 among bystander-witnessed arrests (adjusted OR 1.57, 95% CI 1.24–1.98), but not among EMS-witnessed arrests. EMS-witnessed arrests without prehospital epinephrine administration were significantly associated with an increased chance of 1-month CPC 1–2 compared with bystander-witnessed arrests with prehospital epinephrine administration (adjusted OR 1.26, 95% CI 1.01–1.56).

Conclusions

High-quality CPR is crucial for increasing neurologically intact survival in OHCA patients with non-shockable rhythm. The additional beneficial effects of prehospital epinephrine administration were observed only among OHCA patients with low-quality CPR.

5227Effects of witness status and time to cardiopulmonary resuscitation by emergency medical services on neurological outcomes in out-of-hospital cardiac arrest patients with non-shockable rhythm

Background

Data on the effects of witness status and time from an emergency call to initiation of cardiopulmonary resuscitation (CPR) by emergency medical service (EMS) providers on neurological outcome in out-of-hospital cardiac arrest (OHCA) patients with non-shockable rhythm according to the first documented rhythm are limited.

Purpose

We aimed to determine the effects of witness status and time from an emergency call to CPR initiation by EMS providers on neurologically intact survival in OHCA patients according to the type of non-shockable rhythm (pulseless electrical activity [PEA] and asystole).

Methods

We analysed the records of 583,431 adult OHCA patients with non-shockable rhythm (191,905 bystander-witnessed arrest and 391,526 unwitnessed arrest). Data were derived from the prospectively recorded All-Japan OHCA registry between 2011 and 2016. Call to EMS-CPR interval was defined as the time from an emergency call to CPR initiation by EMS providers. The primary outcome was 1-month neurologically intact survival (cerebral performance category 1 or 2; CPC 1–2) and secondary outcome was presence of PEA.

Results

The rates of 1-month CPC 1–2 were 1.21% (2,326/191,905) for bystander-witnessed arrest and 0.24% (959/391,526) for unwitnessed arrest. When divided into 4 groups based on witness status and initial documented rhythm, these rates were 2.42% (1,869/77,190) for bystander-witnessed arrest with PEA (group A), 0.40% (457/114,715) for bystander-witnessed arrest with asystole (group B), 1.51% (679/44,926) for unwitnessed arrest with PEA (group C) and 0.08% (280/346,600) for unwitnessed arrest with asystole (group D). Multivariate logistic regression analysis revealed each 1-min delay of Call to EMS-CPR interval to be significantly associated with decreased chances of 1-month CPC 1–2 for groups A, B and D (adjusted odds ratio [OR]: 0.95, 0.91 and 0.96, respectively; 95% confidence interval [CI]: 0.93–0.96, 0.88–0.94 and 0.93–0.99, respectively). However, for group C, there was no significant relationship between these variables (adjusted OR: 1.00; 95% CI: 0.98–1.02). The proportion of PEA was 40.2% (77,190/191,905) for bystander-witnessed arrest and 11.5% (44,926/391,526) for unwitnessed arrest. Multivariate logistic regression analysis revealed that, as Call to EMS-CPR interval lengthened (per 1-min delay), the number of OHCA patients with PEA decreased for bystander-witnessed arrest (adjusted OR: 0.94; 95% CI: 0.93–0.94) and for unwitnessed arrest (adjusted OR: 0.96; 95% CI: 0.96–0.97).

Conclusions

The 1-month CPC 1–2 rate differed by witness status and initial documented rhythm in OHCA patients with non-shockable rhythm. Shortening of Call to EMS-CPR interval is crucial for improving 1-month CPC 1–2 rate and sustaining PEA, particularly in bystander-witnessed arrest.