OP0223 DISTINGUISHING OSTEOARTHRITIS AND RHEUMATOID ARTHRITIS SYNOVIUM WITH MACHINE LEARNING USING AUTOMATED CELL DENSITY AND PATHOLOGIST SCORES

Background

Joint damage in the knee can be severe in both rheumatoid arthritis (RA) and osteoarthritis (OA) such that total knee replacement (TKR) is often the only management option. Pathological assessment of the extent or type of synovial tissue inflammation from joint explants or biopsies can be useful. However, an ongoing challenge in using semi-quantitative assessments of synovitis is the disagreement between human pathologist scores of the same sample. We previously developed and validated a computer vision algorithm to automatically count each cell nucleus in an H&E-stained synovial whole slide image and yield a value of cell density, defined as mean nuclei count per mm2 of tissue1.

Objectives

We sought to develop methods to distinguish OA from RA based on machine learning analysis of histologic features on H&E-stained synovial tissue samples.

Methods

We measured 14 pathologist-scored histology features (137 RA and 152 OA patients) and computer vision quantified cell density (60 RA and 147 OA patients) in H&E stained synovial tissue samples from total knee replacement arthroplasty explants. A random forest model was trained using disease state (OA vs RA) as classifier and histology features and/or cell density as inputs, and feature importance scores for the model were calculated.

Results

Synovium from patients with RA exhibited increased lymphocytic inflammation, lining hyperplasia, neutrophils, detritus, plasma cells, Russell bodies, binucleate plasma cells, sub-lining giant cells, synovial lining giant cells, and fibrin (all p<0.001), while synovium from patients with OA had increased mast cells and fibrosis (both p<0.001). Fourteen pathologist-scored features allowed for discrimination between RA and OA samples, producing a macro-averaged area under the receiver operating curve (AUC) of 0.85. This discriminatory ability was comparable to that of the computer vision score of cell density alone (AUC = 0.88). Combining the pathologist scores with the cell density metric improved the discriminatory power of the model (AUC = 0.91). The three most important features in this combined model were mast cells followed by cell density and fibrosis (Figure 1). AUC values for each individual feature are provided in Table 1. The optimal cell density threshold to distinguish RA from OA synovium was 3,400 cells per mm2, which yielded a sensitivity of 0.82 and specificity of 0.82.

Table 1.

Area under receiver operating characteristic curves (AUC) of the synovial features in distinguishing RA and OA patients

FeatureAUCAutomated Cell Density0.88Fibrosis0.84Mast cells0.80Lining hyperplasia0.78Lymphocytic inflammation0.69Fibrin0.68Plasma cells0.66Detritus0.64Binucleate plasma cells0.60Neutrophils0.60Synovial giant cells0.58Sub-lining giant cells0.57Russell bodies0.56Germinal centers0.51Mucoid change0.50Figure 1.

Importance of synovial features in distinguishing RA and OA synovium

Feature importance scores for supervised machine learning model including all 14 pathology scores and the computer vision-generated cell density.

Conclusion

H&E-stained images of RA and OA TKR explant synovium are distinct. We identified cell density, mast cells and fibrosis as the three most important features for making this distinction, with RA being characterized by increased cell density, low mast cells, and low fibrosis. Cell density greater than 3400 per mm2 of tissue yields a sensitivity of 0.82 and a specificity of 0.82 for distinguishing RA from OA. In the future, this can have clinical and research applications as this technique removes the requirement for subjective selection of a certain field of interest, is reproducible, and is scalable as it does not require technical expertise of a pathologist.

References

[1]Guan S, Mehta B…Orange DE. Rheumatoid Arthritis Synovial Inflammation Quantification Using Computer Vision. ACR Open Rheumatology. 2022 Jan 10;acr2.11381.

Acknowledgements

This work was supported by the C. Ronald MacKenzie Young Scientist Endowment Award, the Leon Lowenstein Foundation, and the Kellen Scholar Award supported by the Anna Marie and Stephen Kellen Foundation Total Knee Improvement Program.

Disclosure of Interests

Bella Mehta Paid instructor for: Novartis, Susan Goodman Consultant of: UCB, Grant/research support from: Novartis, Edward DiCarlo: None declared, Deanna Jannat-Khah Shareholder of: AstraZeneca, Cytodyn, and Walgreens, J. Alex Gibbons: None declared, Miguel Otero Consultant of: Regeneron Pharmaceuticals, Grant/research support from: Tissue Genesis, Laura Donlin Speakers bureau: Stryker, Consultant of: Stryker, Grant/research support from: Karius, Inc, Tania Pannellini: None declared, William Robinson: None declared, Peter Sculco Consultant of: Intellijoint Surgical, DePuy Synthes, Lima Corporate, Zimmer Biomet, and EOS Imaging, Grant/research support from: Intellijoint Surgical and Zimmer Biomet, Mark Figgie Shareholder of: HS2, Mekanika, and Wishbone, Consultant of: Lima and Wishbone, Jose Rodriguez Consultant of: ConforMIS, Medacta, Exactech, Inc, and Smith & Nephew, Grant/research support from: DePuy, Exactech, Inc, and Smith & Nephew, Jessica Kirschmann: None declared, James Thompson: None declared, David Slater: None declared, Damon Frezza: None declared, Zhenxing Xu: None declared, Fei Wang: None declared, Dana Orange: None declared

POS0417 LESS ACPA EPITOPE EXPANSION IS FOUND IN ACPA-POSITIVE IMMUNE CHECKPOINT INHIBITOR ARTHRITIS PATIENTS COMPARED TO ACPA-POSITIVE RHEUMATOID ARTHRITIS PATIENTS

Background

Immune checkpoint inhibitors (ICI) have markedly improved the treatment of many advanced cancers; however, they can result in immune-related adverse events (irAE) including ICI arthritis (ICI-A). ICI-A often resembles rheumatoid arthritis (RA) and ~9% of ICI-A patients are anti-citrullinated peptide antibody (ACPA) positive. In RA, ACPA epitope expansion occurs over the years prior to onset of clinical disease. In this study we examined the degree of ACPA epitope expansion in seropositive ICI-A patients in order to determine whether it is similar to early RA, or more suggestive of the pre-clinical phase of disease1.

Objectives

To compare the number of ACPA epitopes targeted in seropositive ICI-A versus RA.

Methods

We used clinical data and serum from 12 ACPA+ ICI-A patients enrolled in a prospective registry and 39 ACPA+ RA patients enrolled in the CATCH-US early RA cohort. ACPA screening was done using a commercial ELISA (positive >20 units/mL). A custom, bead-based antigen array was used to identify antibody reactivities to 16 putative RA associated citrullinated proteins. Synovial fluid (SF) samples from 3 of the ICI-A patients were also tested using the bead-based microarray. Hierarchical clustering software was used to create heatmaps to identify ACPA levels. Z-scores for fluorescence intensity were also calculated separately for each peptide, and a fluorescence level above the mean (Z-score>0) was defined as a positive ACPA. The number of positive epitopes for each patient was determined and compared categorically between the ICI-A and RA patients using Fischer’s exact test.

Results

Characteristics of ICI-A and early RA patients are listed in Table 1. Compared to RA patients, ICI-A patients were older (mean 71 years vs. 48 years), more likely to have ever smoked (67% vs. 36%) and less likely to have positive rheumatoid factor (RF) (8% vs. 69%). Median symptom duration for ICI-A patients was 3.7 months compared to 6.7 months in RA patients. The median ACPA titer was lower in ICI-A patients than RA patients (42 units/mL vs. 250 units/mL). As demonstrated in Figure 1, lower signal intensities (level of ACPA) and a lower number of distinct ACPA epitopes were seen in the serum of ICI-A patients compared to RA patients. Of ICI-A patients, 67% were positive for 0-4 ACPA epitopes, 8% for 5-10 epitopes and 25% for >10 epitopes, as opposed to 23% of RA patients positive for 0-4 epitopes, 36% for 5-10 epitopes, and 41% for >10 epitopes (p=0.02). The one ICI-A patient who was also RF positive had 12 positive ACPA epitopes. There was no significant difference in the number of ACPA epitopes in ICI-A patients who were smokers vs. nonsmokers, RA-like vs. PMR-like, or who received ICI combination vs. ICI monotherapy. In the 3 ICI-A patients with synovial fluid samples, SF ACPA was not demonstrated.

Table 1.

Baseline Characteristics of ACPA+ ICI-A and RA Patients

ICI-A (N=12)Early RA (N=39)Age in years, mean (SD)71.0 (8.3)48.2 (14.6)Female Sex7 (58%)33 (85%)White/Caucasian9 (75%)27 (69%)Symptom Duration in months, median [IQR]3.7 [1.0,11.3]6.7 [4.0,9.7]RF Positive1 (8%)27 (69%)ACPA level (units/mL), median [IQR]42.2 [29.4,70.5]250 [107.5,251.0]Obese (BMI≥30)3 (25%)9 (23%)Current/Past Smoker8 (67%)14 (36%)Cancer Typeǂ Melanoma4 (33%) Renal Cell Carcinoma3 (25%)ICI Regimen PD-1/PD-L17 (58%) CTLA-4+PD-15 (42%)ICI-A Phenotype RA-like9 (75%) PMR-like3 (25%)

ǂOther cancer types in ICI-A patients included urothelial carcinoma (n=2), non-small cell lung cancer (n=2), and head and neck cancer (n=1).

Figure 1.

Heat Map of ACPA repertoire in RA Patients and ICI-A Patients.

Conclusion

ICI-A patients had lower ACPA titers and targeted fewer ACPA epitopes than early RA patients. It remains to be determined if ICI-A represents an accelerated model of RA pathogenesis with ICI triggering an early transition from pre-clinical to clinical disease. This would require sequential sampling and analysis.

References

[1]Sokolove J. et al. PLoS One. 2012;7(5)e35296

Disclosure of Interests

Diviya Rajesh: None declared, Nilasha Ghosh: None declared, Jessica Kirschmann: None declared, Karmela Kim Chan: None declared, Deanna Jannat-Khah Shareholder of: AstraZeneca, Walgreens, and Cytodyn, Susan Goodman Consultant of: UCB Data Monitoring and Safety Board, Grant/research support from: Novartis, Vivian Bykerk Consultant of: Amgen, Bristol Myers Squibb, Genzyme, Gilead, Janssen, Pfizer, Sanofi-Aventis, and UCB, Grant/research support from: Bristol Myers Squibb, Amgen, and The Cedar Hill Foundation, William Robinson: None declared, Anne Bass: None declared.

Non-invasive myocardial work: characterising the normal and ischaemic response to exercise

Background/Introduction

Myocardial work and work efficiency are new parameters for assessing left ventricular function. They have been shown to have value in a range of clinical settings but have not previously been applied to exercise stress echocardiography.

Purpose

We aim to characterize the normal myocardial work and work efficiency response to exercise in a mixed population and determine if myocardial work could be used to identify patients with inducible ischaemia.

Methods

Patients were retrospectively enrolled from an existing database of exercise stress echocardiography. Inclusion criteria were a clinical indication of possible ischemia and technical suitability to calculate myocardial work. Exclusion criteria were abnormal baseline left ventricular function or inadequate image quality. Echocardiograms positive for ischaemia were defined by independent visual assessment and compared with angiographic findings where available. Myocardial work and work efficiency were calculated using a proprietary algorithm.

Results

A total of 177 patients met inclusion criteria, 117 were excluded leaving 40 normal and 20 positive tests for analysis. During normal exercise global work increased 54% and efficiency remained at 96%. Segmental work showed a basal to apical gradient which became more prominent at peak exercise. In patients with inducible ischaemia during exercise there was a significant difference in response; work decreased by 1.9% and efficiency dropped to 87%. Receiver operating characteristic curve for myocardial work had an area under the curve of 0.94. Youden's J statistic suggested an optimum cut point of a 25% increase in work to define a normal test.

Conclusion

During normal exercise myocardial work increased and efficiency remained unchanged, however during exercise induced ischaemia both myocardial work and efficiency decreased. We have demonstrated that myocardial work can be applied to stress echocardiography to identify ischemia but the utility of this remains uncertain. Further research compared to an objective measure of functional ischemia is needed.

Response to exercise

Funding Acknowledgement

Type of funding source: None

SAT0003 ELEVATED BASELINE AND INCREASING AUTOANTIBODY LEVELS ARE ASSOCIATED WITH INCREASED RISK FOR IMMINENT ONSET OF INFLAMMATORY ARTHRITIS IN A PROSPECTIVELY STUDIED ANTI-CITRULLINATED PROTEIN ANTIBODY POSITIVE COHORT: THE TIP-RA COLLECTIVE

Background:

The Targeting Immune Responses for Prevention of RA (TIP-RA) Collaborative prospectively studies individuals at high risk for developing RA because of serum ACPA positivity in absence of baseline inflammatory arthritis (IA).

Objectives:

The objective of the analyses presented herein is to evaluate the role of baseline and changing levels of ACPA and rheumatoid factor (RF) in relationship to incident IA/RA.

Methods:

ACPA+ subjects and ACPA- controls were identified who did not have baseline historical or examination evidence of IA. ACPA+ was defined by serum elevation of anti-CCP3 ≥20 units (Inova). Subjects were evaluated annually or sooner if they had changes in joint symptoms. Factors including RFIgM and RFIgA (Inova) were also assessed, and relationships between autoantibody levels at baseline and over time and incident IA/RA were evaluated using t-tests, with paired testing where applicable.

Results:

Baseline characteristics of ACPA+ and ACPA- subjects are in Table 1. Sixteen of the 94 (17%) ACPA+ subjects developed IA/RA a mean of 518 days from the baseline visit; 14 of these met 2010 ACR/EULAR criteria for RA at the time of detection of IA. There was a trend for ACPA+ subjects who later developed IA/RA to have higher baseline levels of anti-CCP3 compared to those who did not develop IA/RA (Table 2). In addition, those who developed IA/RA had significantly higher mean levels of RFIgM and RFIgA compared to those who did not. While not statistically significant, in longitudinal analyses in the ACPA+ subjects with incident IA/RA, anti-CCP3 levels increased from baseline to identification of IA (mean [SD] of 119 [102] to 126 [100], p=0.42). Furthermore, RFIgM levels increased from 36 [49] at baseline to 43 [51] at the time of IA (p=0.31), and RFIgA levels increased from 16 [29] to 21 [31] (p=0.10). In contrast, in ACPA+ subjects who did not develop IA/RA, anti-CCP3 levels increased only slightly over follow-up of a mean of 712 days: 75 [75] to 80 [76], p=0.70 while the levels of RFIgM and RFIgA decreased slightly during the same follow-up: for RFIgM mean [SD] levels went from 9 [22] to 8 [19], p=0.74; for RFIgA, 5 [16] to 3 [12], p=0.67.

Table 1.

Baseline characteristics of ACPA+/- subjects

ACPA-(n=162)ACPA+(n=94)p-valueAge, mean58580.90% Female69680.67% Ever smoker33340.87RF-IgM, mean (SD)3.2 (10.0)13.5 (30.2)<0.01RF-IgA, mean (SD)0.3 (0.6)6.5 (19.1)<0.01Table 2.

Baseline characteristics of 16 ACPA+ subjects who developed incident IA/RA vs. 78 ACPA+ who did not

Did not develop IA/RA (n=78)Developed IA/RA (n=16)p-valueDays from baseline to IA/RA or follow-up, mean (SD)712 (124)518 (295)–% Meeting 2010 criteria at time of IA-88–CCP3, mean (SD)74.5 (75.3)119.1 (102.1)0.05RFIgM, mean (SD)9 (22)36 (49)<0.01RFIgA, mean (SD)4 (16)16 (29)0.03

Conclusion:

In this prospectively followed cohort of ACPA+ subjects, higher levels of RFIgM and RFIgA at baseline were significantly associated with development of IA/RA within the follow-up period. Furthermore, there was a trend for rising levels of anti-CCP3 and RFIgM and A to be associated with development of IA/RA. These finding support the use of higher and/or rising levels of autoantibodies as additional features to predict imminent onset of IA/RA in ACPA+ individuals as well as potentially to use as outcomes of success of preventive interventions. Furthermore, the trend of increasing levels of RFIgM and RFIgA over time in individuals who developed IA/RA suggests that targeting pathways of RF development may lead to preventive interventions in a subset of RA.

References:

None

Disclosure of Interests:

Kevin Deane Grant/research support from: Janssen, Consultant of: Inova, ThermoFisher, Janseen, BMS and Microdrop, Gary Firestein Grant/research support from: Lilly, Janssen, Abbvie, David Boyle: None declared, Jane Buckner Grant/research support from: Bristol-Myers Squibb, Janssen, Eddie A. James Grant/research support from: Janssen, Pfizer, Sanofi, Novartis, Sylvia Posso Grant/research support from: Janssen, William Robinson Grant/research support from: Janssen, Laurie K. Moss Grant/research support from: Janssen, Jennifer Seifert Grant/research support from: Janssen, Roger Gilmore Grant/research support from: Janssen, Saman Barzideh Grant/research support from: Janssen, Navin Rao Shareholder of: Janssen Pharmaceuticals, Employee of: Janssen Pharmaceuticals, Frederic Baribaud Shareholder of: Janssen Research & Development, LLC, Employee of: Janssen Research & Development, LLC, Sunil Nagpal Shareholder of: Janssen Pharmaceuticals, Employee of: Janssen Pharmaceuticals, Alyssa Johnsen Employee of: Janssen, V. Michael Holers Grant/research support from: Janssen, Celgene, and BMS

SAT0596 ASSOCIATIONS BETWEEN CIRCULATING LIPID MEDIATORS AND INCIDENT INFLAMMATORY ARTHRITIS IN AN ANTI-CITRULLINATED PROTEIN ANTIBODY POSITIVE POPULATION

Background:

Lipid mediators are endogenously derived from the metabolism of omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) and have important roles in promoting and resolving inflammation in the body (1). Epidemiological studies have shown higher omega-3 PUFA status to be associated with a lower risk of both autoimmunity and progression to inflammatory arthritis (IA) (2,3).

Objectives:

To determine the association of lipid mediators with progression from rheumatoid arthritis (RA)-related autoimmunity to inflammatory arthritis (IA).

Methods:

We conducted a prospective cohort study using data from the Studies of the Etiologies of Rheumatoid Arthritis (SERA). SERA enrolled first-degree relatives (FDRs) of individuals with RA (FDR cohort) and individuals who screened positive for RA-related autoantibodies at health fairs (screened cohort). We followed 133 anti-CCP3.1 positive participants, of which 29 developed IA (22 classified as RA by 2010 ACR/EULAR criteria). We quantified lipid mediators from stored plasma samples via liquid chromatography tandem mass spectrometry methods validated against the collection and storage methods used in the study. A priori, we selected 5S-HETE, 15S-HETE and 17S-HDHA because they are precursors to leukotrienes, Lipoxin A4 and Resolvin D series lipid mediators, respectively. We fit Cox proportional hazard models for each lipid mediator as a time-varying covariate. For lipid mediators significantly associated with progression to IA we then examined IL-1β, IL-6, IL-8 and TNF-α (Bio-Plex Pro™ assay) as potential mediators of this relationship.

Results:

Higher plasma 5S-HETE levels were associated with an increased risk of incident IA after adjusting for age at baseline, cohort (FDR or screened), and shared epitope (SE) status (Table 1). The models examining 15S-HETE and 17S-HDHA had the same trend but did not reach statistical significance. We did not find evidence that the association between 5S-HETE and IA risk was mediated by the tested pro-inflammatory cytokines, suggesting a direct role for this lipid mediator in conversion to IA.

Table 1.

Hazard ratios and 95% confidence intervals of lipid mediator concentrations associated with IA, n=29 IA cases

Lipid mediatorCrudeAdjustedb5S-HETE2.10 (1.12, 3.92)2.41 (1.43, 4.07)15S-HETE1.61 (0.88, 2.93)1.52 (0.87, 2.65)17-HDHAa1.59 (0.68, 3.74)1.61 (0.72, 3.56)

adichotomized as <limit of detection (reference) or detected

bAdjusted for SE, age at baseline and cohort

Conclusion:

In a prospective cohort of anti-CCP positive individuals, higher circulating levels of 5S-HETE, an important precursor to pro-inflammatory leukotrienes, was associated with subsequent IA. Our findings highlight the potential pathologic and prognostic significance of these PUFA metabolites in inflammatory processes in pre-RA populations.

References:

[1]Serhan CN. Pro-resolving lipid mediators are leads for resolution physiology. Nature. 2014;510(7503):92-101.

[2]Gan RW, Bemis EA, Demoruelle MK, Striebich CC, Brake S, Feser ML, et al. The association between omega-3 fatty acid biomarkers and inflammatory arthritis in an anti-citrullinated protein antibody positive population. Rheumatology. 2017.

[3]Gan RW, Young KA, Zerbe GO, Demoruelle MK, Weisman MH, Buckner JH, et al. Lower omega-3 fatty acids are associated with the presence of anti-cyclic citrullinated peptide autoantibodies in a population at risk for future rheumatoid arthritis: a nested case-control study. Rheumatology. 2016;55(2):367-76.

Disclosure of Interests:

Kristen Polinski: None declared, Elizabeth Bemis: None declared, Kristen Demoruelle Grant/research support from: Pfizer, Jennifer Seifert: None declared, Tessa Crume: None declared, Fan Yang: None declared, William Robinson: None declared, Michael Clare-Salzler: None declared, Kevin Deane Grant/research support from: Janssen, Consultant of: Inova, ThermoFisher, Janseen, BMS and Microdrop, Michael Holers Shareholder of: AdMIRx, Grant/research support from: AdMIRx, Pfizer, Janssen R&D, Consultant of: AdMIRx, Janssen R&D, Celgene, Bristol-Myers Squibb, Jill Norris Grant/research support from: Janssen R&D, Pfizer, Consultant of: Celgene, BMS

OP0337 DIFFERENTIAL METHYLATION OF PERIPHERAL BLOOD ADAPTIVE IMMUNE CELLS IN INDIVIDUALS AT HIGH RISK FOR RA AND WITH EARLY RA COMPARED WITH CONTROLS IDENTIFIES PATHWAYS IMPORTANT IN TRANSITION TO ARTHRITIS

Background:

The “Targeting Immune Responses for Prevention of RA” (TIP-RA) collaboration studies individuals at high risk for developing RA because of serum anti-citrullinated protein antibody positivity in absence of arthritis, and is focused on defining how they transition from at-risk to classifiable disease. One potential mechanism is through alterations in epigenetics patterns in adaptive immune cells.

Objectives:

Previous studies showed that DNA methylation patterns of early RA (ERA) synoviocytes differ from long-standing RA, suggesting that abnormal methylation occurs early in synovium and evolves over time. To extend these observations, we performed a cross-sectional analysis in TIP-RA of DNA methylation signatures in peripheral blood cells in ERA, at-risk anti-CCP3+ individuals and demographically matched CCP- controls.

Methods:

Genomic DNA was isolated from two independent cohorts of CCP- (cohorts 1 and 2, respectively: B cell: n = 17/34; memory T cell: n = 21/34; and naïve T cell: n = 21/33), CCP3+ (B cell: n = 18/37; memory T cell: n = 20/36; and naïve T cell: n = 20/35), and CCP3+ ERA (B cell: n = 4/18; memory T cell: n = 5/18; and naïve T cell: n = 5/18) after separating PBMCs using antibodies and magnetic beads. Methylation was measured by Illumina Infinium MethylationEPIC chip. Differentially methylated loci (DMLs) were identified using Welch’s t-test and mapped to gene promoter regions to define DM genes (DMGs). Principal component analysis (PCA) was used to represent relationship among groups. Pathway analysis was applied by Reactome.

Results:

For the initial cohort, 1494, 1097 and 1330 DMLs were identified among CCP+, CCP- and ERA in B cells, memory T cells and naïve T cells, respectively. For the confirmatory cohort, 523, 793 and 548 DMLs were found in corresponding cell populations. The DML overlap between the 2 cohorts was highly significant (p= 2.48E-77). The DMLs were combined for both groups and corresponded to 411, 412, and 351 DMGs in B cells, memory T cells and naïve T cells. Of these, we found 246, 198 and 195 DMGs between CCP3+ and ERA in each peripheral blood cell population, respectively. PCA showed separation of CCP+, CCP- and ERA in each of the three blood cell types by DMLs (Fig. 1). DMGs were mapped to biological pathways to identify DM pathways. Although most were not significant, there were several highly significant differences comparing CCP+, ERA and CCP- in memory T cells involving pathways, including “Interferon gamma signaling” (FDR 7.48E-14), “PD-1 signaling” (FDR 8.71E-10), “Translocation of ZAP-70 to Immunological synapse” (FDR 4.75E-10), and “Phosphorylation of CD3 and TCR zeta chains” (FDR 8.71E-10).

Figure 1.

PCA shows the separation of CCP+, CCP- and ERA patients in memory T cells in confirmatory cohort.

Conclusion:

We identified reproducible methylation signatures of CCP-, CCP+, and ERA in peripheral blood B cells, memory T cells and naïve T cells in initial and confirmatory cohorts. The methylome of ERA also demonstrated a distinctive pattern from CCP+, indicating that progression to RA is accompanied by epigenetic remodeling, especially in T cell signaling and interferon responses. These signatures identify critical pathways in CCP positivity and classifiable RA and could provide the basis of novel interventions to prevent disease.

Disclosure of Interests:

Rizi Ai: None declared, David Boyle: None declared, Deepa Hammaker: None declared, Kevin Deane Grant/research support from: Janssen, Consultant of: Inova, ThermoFisher, Janseen, BMS and Microdrop, V. Michael Holers Grant/research support from: Janssen, Celgene, and BMS, Andre Matti: None declared, William Robinson: None declared, Jane Buckner Grant/research support from: Bristol-Myers Squibb, Janssen, Navin Rao Shareholder of: Janssen Pharmaceuticals, Employee of: Janssen Pharmaceuticals, Frederic Baribaud Shareholder of: Janssen Research & Development, LLC, Employee of: Janssen Research & Development, LLC, Alyssa Johnsen Employee of: Janssen, Sunil Nagpal Shareholder of: Janssen Pharmaceuticals, Employee of: Janssen Pharmaceuticals, Wei Wang: None declared, Gary Firestein Grant/research support from: Lilly, Janssen, Abbvie

Assessing adequacy of emergency provider documentation among interhospital transferred patients with acute aortic dissection

BACKGROUND

Acute aortic dissection (AoD) is a hypertensive emergency often requiring the transfer of patients to higher care hospitals; thus, clinical care documentation and compliance with the Emergency Medical Treatment and Active Labor Act (EMTALA) is crucial. The study assessed emergency providers (EP) documentation of clinical care and EMTALA compliance among interhospital transferred AoD patients.

METHODS

This retrospective study examined adult patients transferred directly from a referring emergency department (ED) to a quaternary academic center between January 1, 2011 and September 30, 2015. The primary outcome was the percentage of records with adequate documentation of clinical care (ADoCC). The secondary outcome was the percentage of records with adequate documentation of EMTALA compliance (ADoEMTALA).

RESULTS

There were 563 electronically identified patients with 287 included in the final analysis. One hundred and five (36.6%) patients had ADoCC while 166 (57.8%) patients had ADoEMTALA. Patients with inadequate documentation of EMTALA (IDoEMTALA) were associated with a higher likelihood of not meeting the American Heart Association (AHA) ED Departure SBP guideline (OR 1.8, 95% CI 1.03-3.2, P=0.04). Male gender, handwritten type of documentation, and transport by air were associated with an increased risk of inadequate documentation of clinical care (IDoCC), while receiving continuous infusion was associated with higher risk of IDoEMTALA.

CONCLUSION

Documentation of clinical care and EMTALA compliance by Emergency Providers is poor. Inadequate EMTALA documentation was associated with a higher likelihood of patients not meeting the AHA ED Departure SBP guideline. Therefore, Emergency Providers should thoroughly document clinical care and EMTALA compliance among this critically ill group before transfer.

Biological variation of routine haematology and biochemistry measurands in the horse

BACKGROUND

Clinical pathology results are typically interpreted by referring to population-based reference intervals. The use of individualised (subject-based) reference intervals is more appropriate for measurands with a high degree of variation between individuals.

OBJECTIVES

To determine the biological variation of routinely analysed equine haematology and biochemistry measurands and calculate indices of individuality and reference change values which enable production of individualised reference intervals, in a group of healthy, privately owned horses.

STUDY DESIGN

In a prospective cohort study, thirty-nine privately owned horses were sampled by jugular venipuncture for analysis of haematology and biochemistry measurands at weekly intervals for 6 weeks.

METHODS

Haematology was analysed on the day of collection. Serum was frozen and biochemistry analyses performed on thawed samples. Duplicate results were obtained and the coefficient of variation was calculated for analytical variation, within-subject variation and between-subject variation. The index of individuality and reference change value were derived for each measurand.

RESULTS

Haematology (red blood cell count, mean corpuscular haemoglobin and mean cell volume) and biochemistry measurands (total protein, globulins, albumin, gamma-glutamyl transferase, aspartate aminotransferase) demonstrated high individuality, indicating that individualised reference intervals are more appropriate for evaluation of these measurands. Two haematology (mean corpuscular haemoglobin concentration and platelets) and three biochemistry measurands (chloride, glucose and sodium) had low individuality, indicating that the use of traditional population-based reference intervals is appropriate for these measurands. Remaining measurands had intermediate individuality suggesting interpretation of the reference change value should occur with consideration of the population-based reference interval.

MAIN LIMITATIONS

The use of privately owned horses, variable management and environmental factors.

CONCLUSIONS

The use of individualised reference intervals is justified for many measurands in horses, supporting the use of serial sampling, consideration of biological variation and application of reference change values for improved clinical decision making and patient management in equine practice.

Evaluation of Monoclonal Antibodies to vWf Antigen for Use in Autoradiographing vWf Multimer Analysis

Nine monoclonal antibodies (MAb, coded ESvWF 1-5, 7-10) to human von Willebrand’s factor (vWf) have been studied for their labelling characteristics with 125I and their ability to demonstrate vWf multimers by autoradiography after discontinuous SDS electrophoresis on agarose and agarose/acrylamide gels in plasma from normal and von Willebrand’s disease (vWD) patients. Of ESvWF 1, 2, 4, 7, 8 and 9, ESvWF 2 gave autoradiographs most similar to those obtained with a polyclonal antibody. The others gave much fainter staining of all bands suggesting that the epitope detected by ESvWF 2 is either more common or, less easily altered by SDS than the epitopes identified by the other MAb’s. ESvWF 2 gave a different staining pattern with a IIC vWD patient than that obtained using a polyclonal antibody. The most striking result, however, was shown by ESvWF 3, 5 and 10 which failed to stain the lower band of the lower molecular weight multimer. This suggests that the lower triplet band, unlike the central and upper bands of the triplet, does not contain the epitope identified by these three MAb’s. With these reagents it has been possible to show, for the first time, that epitope differences do exist between the constituent bands of the vWf triplet.

Abstract PD8-01: Race and age differences in PAM50 biomarker status in the Carolina breast cancer study

Background: African American breast cancer patients have lower relative frequency of hormone receptor (HR)-positive/HER2-negative disease and higher subtype-specific mortality. However, few population-based studies have RNA-based subtyping data, and racial differences in the biology of HR-positive/HER2-negative tumors are not well understood.

Methods: Using data and biospecimens from the Carolina Breast Cancer Study (CBCS) Phase 3 (2008-2013), we classified approximately 1,000 invasive breast cancers according to PAM50 subtype and two risk of recurrence scores (ROR-P and ROR-PT). Relative frequency of Luminal A, Luminal B, Her2-enriched, and Basal-like subtypes and ROR scores (low/medium/high) were compared by race (blacks vs. whites) and age (≤50 years vs. &gt;50 years), overall and among HR-positive/HER2-negative cases.

Results: Black women of all ages had significantly higher relative frequency of Basal-like breast cancer (36 and 31% in blacks vs. 18 and 15% in whites; younger and older, respectively) and lower frequency of Luminal A breast cancer (26 and 34% in blacks vs. 43 and 52% in whites; younger and older, respectively). Frequency of Luminal B and HER2-enriched breast cancer did not vary by race or age. Among clinically HR-positive, HER2-negative cases, Luminal A subtype comprised only half of the cases among black women, and was significantly less common than among white women (51% vs 60% in whites, p&lt;0.05). Black women with HR-positive/HER2-negative disease also had significantly higher ROR scores (ROR-P medium or high 82% vs. 66% in whites, p=0.01; ROR-PT medium or high 85% vs. 69% in whites, p&lt;0.01).

Conclusions: Multi-gene assays highlight disparities in frequency of aggressive, poorer prognosis tumor subtypes and implicate differences in tumor biology as an important contributor to mortality disparities among HR-positive/HER2-negative patients.

Citation Format: Troester MA, Sun X, Allott EH, Kit C-K, Thorne L, Mathews M, Cohen SM, Geradts J, Kirk E, Li Y, Hu Z, Robinson W, Hoadley KA, Reeder-Hayes K, Earp S, Olshan AF, Carey LA, Perou CM. Race and age differences in PAM50 biomarker status in the Carolina breast cancer study [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD8-01.

A piecewise regression approach for determining biologically relevant hydraulic thresholds for the protection of fishes at river infrastructure

A piecewise regression approach was used to objectively quantify barotrauma injury thresholds in two physoclistous species, Murray cod Maccullochella peelii and silver perch Bidyanus bidyanus, following simulated infrastructure passage in a barometric chamber. The probability of injuries such as swimbladder rupture, exophthalmia and haemorrhage, and emphysema in various organs increased as the ratio between the lowest exposure pressure and the acclimation pressure (ratio of pressure change, R(NE:A) ) reduced. The relationship was typically non-linear and piecewise regression was able to quantify thresholds in R(NE:A) that once exceeded resulted in a substantial increase in barotrauma injury. Thresholds differed among injury types and between species but by applying a multispecies precautionary principle, the maintenance of exposure pressures at river infrastructure above 70% of acclimation pressure (R(NE:A) of 0·7) should protect downstream migrating juveniles of these two physoclistous species sufficiently. These findings have important implications for determining the risk posed by current infrastructures and informing the design and operation of new ones.

Transcriptional repression of IFNβ1 by ATF2 confers melanoma resistance to therapy

The resistance of melanoma to current treatment modalities represents a major obstacle for durable therapeutic response, and thus, the elucidation of mechanisms of resistance is urgently needed. The crucial functions of Activating Transcription Factor-2 (ATF2) in the development and therapeutic resistance of melanoma have been previously reported, although the precise underlying mechanisms remain unclear. Here, we report a protein kinase C epsilon (PKCε)- and Activating Transcription Factor-2 (ATF2)-mediated mechanism that facilitates resistance by transcriptionally repressing the expression of IFNβ1 and downstream type-I IFN signaling, which is otherwise induced upon exposure to chemotherapy. Treatment of early stage melanomas expressing low levels of PKCε with chemotherapies relieves its transcriptional repression of IFNB1, resulting in impaired S-phase progression, a senescence-like phenotype, and increased cell death. This response is lost in late stage metastatic melanomas expressing high levels of PKCε. Notably, nuclear ATF2 and low expression of IFNβ1 in melanoma tumor samples correlates with poor patient responsiveness to biochemotherapy or neoadjuvant IFN-α2a. Conversely, cytosolic ATF2 and induction of IFNβ1 coincides with therapeutic responsiveness. Collectively, we identify an IFNβ1-dependent, cell autonomous mechanism that contributes to the therapeutic resistance of melanoma via the PKCε-ATF2 regulatory axis.

IFPA meeting 2014 workshop report: Animal models to study pregnancy pathologies; new approaches to study human placental exposure to xenobiotics; biomarkers of pregnancy pathologies; placental genetics and epigenetics; the placenta and stillbirth and fetal growth restriction

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2014 there were six themed workshops, five of which are summarized in this report. These workshops related to various aspects of placental biology but collectively covered areas of animal models, xenobiotics, pathological biomarkers, genetics and epigenetics, and stillbirth and fetal growth restriction.

The beta-lactam antibiotic, ceftriaxone, attenuates morphine-evoked hyperthermia in rats

BACKGROUND AND PURPOSE

Beta-lactam antibiotics are the first practical pharmaceuticals capable of increasing the expression and activity of the glutamate transporter, GLT-1, in the CNS. However, the functional impact of beta-lactam antibiotics on specific drugs which produce their pharmacological effects by increasing glutamatergic transmission is unknown. One such drug is morphine, which causes hyperthermia in rats, mediated by an increase in glutamatergic transmission. Since drugs (e.g. antibiotics) that enhance glutamate uptake also decrease glutamatergic transmission, we tested the hypothesis that ceftriaxone, a beta-lactam antibiotic, would block the glutamate-dependent portion of morphine-evoked hyperthermia.

EXPERIMENTAL APPROACH

A body temperature assay was used to determine if ceftriaxone decreased morphine-induced hyperthermia in rats by increasing glutamate uptake.

KEY RESULTS

Body temperatures of rats treated with ceftriaxone (200 mg kg(-1), i.p. x 7 days) did not differ from rats receiving saline. Morphine (1, 4, 8 and 15 mg kg(-1), s.c.) caused significant hyperthermia. Pre-treatment with ceftriaxone, as described above, decreased the hyperthermic response to these doses of morphine. The effects of ceftriaxone were prevented by TBOA (0.2 micromol, i.c.v.), an inhibitor of glutamate transport.

CONCLUSIONS AND IMPLICATIONS

Ceftriaxone attenuated the hyperthermia caused by morphine, an effect prevented by inhibiting glutamate transport. Thus this effect of ceftriaxone was most likely mediated by increased glutamate uptake. These data revealed a functional interaction between ceftriaxone and morphine and indicated that a beta-lactam antibiotic decreased the efficacy of morphine in conscious rats.

MicroRNA regulation in mantle cell lymphoma

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Mantle Cell Lymphoma (MCL) represents only 5–10% of all non-Hodgkins lymphomas, making it an uncommon but difficult form of lymphoma to treat. It has the worst prognosis among the B cell lymphomas with median survival of three years. The genetic hallmark of MCL is a t(11;14) q32 translocation which results in ectopic and dysregulated expression of cyclin D1. Recent comparative genomic hybridization studies have identied Syk as another gene important in the pathogenesis of MCL. Previous studies have suggested that post transcriptional regulation of Cyclin D1 and Syk may be important the pathogenesis of in MCL. MicroRNAs are a new class of abundant small RNAs that play important regulatory roles at the post transcriptional level by binding to the 3’ untranslated region (UTR) of mRNAs blocking either their translation or initiating their degradation. There have been numerous reports of misregulation of microRNAs and their targets in human cancers. We hypothesized that altered microRNA regulation of cyclin D1 and/or Syk may be present in MCL. Based on bioinformatics, we identified 8 microRNAs and their putative docking sites in either Cyclin D1 and Syk. We then examined their integrity in MCL cell lines, and identified a mutation in the 3’UTR of Syk at the docking site of 1 mir-452* and a SNP in mir-458. Using a GFP reporter construct with the mutated Syk 3’UTR we demonstrated that this mutation resulted in altered microRNA function. We also show that mimics of the microRNA leads to down regulation of Syk protein. This data suggests that microRNA regulation of important genes in MCL may be compromised and play a role in the development and progression of this disease.

No significant financial relationships to disclose.

Palliative care in cystic fibrosis

Although advances in therapy for cystic fibrosis (CF) have dramatically increased the average life span of patients, the disease is still uniformly fatal. Little attention has been paid to methods of palliative care for patients with cystic fibrosis in the medical literature. The primary palliative care issue in end-stage CF is the management of dyspnea. An observational study done at Children's Hospital in Boston suggested that doses of morphine in the range of 5 mg per hour can control the end-stage dyspnea in CF of over 50% of patients; the rest required increasing doses with the highest dose required being 30 mg/hour. The use of mechanical ventilation at the end of life is increasing in CF, particularly for those patients awaiting lung transplantation, and it appears that the consensus against the use of aggressive care at the end of life in CF may be eroding. The use of various modes of assisted ventilation in end-stage CF will add new challenges to the compassionate provision of end-of-life care. In addition to these medical issues, palliative care in CF presents some unique psychosocial issues: there may be more than one family member with the disease, and there is an involved patient community also affected by end-of-life plans. A family-centered approach to end-of-life care for patients with CF is essential.