The impact of pain on daily activities in patients with idiopathic inflammatory myopathies: Report from the OMERACT myositis working group.

BACKGROUND: International focus groups with patients with idiopathic inflammatory myopathies (IIM) conducted by the OMERACT Myositis Working Group over the years demonstrated the pain as an important symptom experienced by these patients. In this study, we aimed to examine the frequency and degree of pain interference, the aspects of daily life impacted by pain, and the factors associated with pain interference in adults with IIM. METHODS: This was a prospective observational study with two visits. The patients who fulfilled the probable/definite IIM (ACR/EULAR Myositis Classification Criteria) were enrolled. Pain interference was assessed with PROMIS pain interference form (6a). Myositis core set measures and PROMIS fatigue (7a) and physical function (8b) were obtained at both visits. Logistic regression and linear mixed models were performed to assess the association between pain interference and other parameters. RESULTS: A total of 129 patients with IIM (60 % females) were recruited from U.S., South Korea, Netherlands, Sweden, and Australia. Approximately 71 % reported pain interference. The patients in the greater pain interference group were more likely to be female, had significantly worse patient/physician global disease activity, fatigue, and physical function than those in the lower pain interference group. The most commonly impacted life aspect was household chores. Manual muscle testing, patient/physician global disease activity, fatigue, and physical function were all significantly associated with pain interference score >60. CONCLUSION: The majority of the patients with IIM experience the impact of pain on their daily activities, particularly household chores. Myositis disease activity, duration, and subtype could be associated with greater pain interference.

Immune checkpoint inhibitor therapy in patients with cancer and pre-existing systemic sclerosis.

OBJECTIVE: Immune checkpoint inhibitor (ICI) therapies have dramatically improved outcomes in multiple cancers. ICI's mechanism of action involves immune system activation to augment anti-tumor immunity. Patients with pre-existing autoimmune diseases, such as systemic sclerosis (SSc), were excluded from initial ICI clinical trials due to concern that such immune system activation could precipitate an autoimmune disease flare or new, severe immune related adverse events (irAE). In the present study, we report our experience with ICIs in patients with pre-existing SSc. METHODS: Patients with SSc who received ICI therapy for cancer were identified from the Johns Hopkins Scleroderma Center Research Registry. Through chart review and prespecified definitions, we identified whether patients experienced worsening SSc activity or new irAEs. SSc disease activity worsening was pre-defined as an increase in modified Rodnan skin score (mRSS), new scleroderma renal crisis, progression of interstitial lung disease (ILD) on CT scan, increased Raynaud's phenomenon frequency or severity, new pulmonary hypertension, or myositis flare. IrAEs also included active inflammatory arthritis and dermatitis. RESULTS: Eight patients with SSc who received ICI therapy for cancer were included. Overall, SSc symptoms remained stable during and after ICI therapy. None of the patients with long-standing sine or limited cutaneous SSc (lcSSc) had progressive skin thickening after ICI therapy. One patient, who was early in his diffuse cutaneous SSc (dcSSc) disease course, experienced worsening skin thickening and renal crisis. Three patients (38 %) experienced a total of five irAEs (grade 2: diarrhea, mucositis and dermatitis; grade 3: pneumonitis, and grade 4: nephritis). The patient with grade 4 nephritis developed scleroderma renal crisis and immune checkpoint related nephritis simultaneously. There were no deaths due to irAEs. CONCLUSION: In this study, ICI therapy was well tolerated in patients with longstanding, sine or lcSSc. IrAE were common but generally manageable. Patients with early, active SSc may be at greater risk from ICI therapy, but more research is needed.

Collaborative research in myositis-related disorders: MIHRA, a global shared community model.

Myositis International Health and Research Collaborative Alliance (MIHRA) is a newly formed purpose-built non-profit charitable research organization dedicated to accelerating international clinical trial readiness, global professional and lay education, career development and rare disease advocacy in IIM-related disorders. In its long form, the name expresses the community's scope of engagement and intent. In its abbreviation, MIHRA, conveys linguistic roots across many languages, that reflects the IIM community's spirit with meanings such as kindness, community, goodness, and peace. MIHRA unites the global multi-disciplinary community of adult and pediatric healthcare professionals, researchers, patient advisors and networks focused on conducting research in and providing care for pediatric and adult IIM-related disorders to ultimately find a cure. MIHRA serves as a resourced platform for collaborative efforts in investigator-initiated projects, consensus guidelines for IIM assessment and treatment, and IIM-specific career development through connecting research networks.MIHRA's infrastructure, mission, programming and operations are designed to address challenges unique to rare disease communities and aspires to contribute toward transformative models of rare disease research such as global expansion and inclusivity, utilization of community resources, streamlining ethics and data-sharing policies to facilitate collaborative research. Herein, summarises MIHRA operational cores, missions, vision, programming and provision of community resources to sustain, accelerate and grow global collaborative research in myositis-related disorders.

Improved lung cancer clinical outcomes in patients with autoimmune rheumatic diseases.

PURPOSE: Concomitant autoimmune rheumatic diseases (ARD) can add morbidity and complicate treatment decisions for patients with lung cancer. We evaluated the tumour characteristics at diagnosis and clinical outcomes in lung cancer patients with or without ARD. METHODS: This retrospective cohort study included 10 963 patients with lung cancer, treated at Johns Hopkins. Clinical data including tumour characteristics and outcomes were extracted from the cancer registry. Data on patients' history of 20 ARD were extracted from the electronic medical record. Logistic regression was used to compare tumour characteristics between those with and without ARD; Kaplan-Meier curves and Cox proportional hazards models were performed to compare survival outcomes. RESULTS: ARD was present in 3.6% of patients (n=454). The mean age at diagnosis was 69 (SD 10) and 68 (SD 12) in patients with and without ARD (p=0.02). Female sex and smoking history were significantly associated with a history of ARD (OR: 1.75, OR: 1.46, p<0.05). Patients with ARD were more likely to be diagnosed with stage 1 lung cancer (36.8% vs 26.9%, p<0.001) and with smaller tumour size (OR: 0.76, p=0.01), controlling for sex, race and histology. Notably, lung cancer patients with ARD had a significantly prolonged median overall survival (OS) (7.11 years vs 1.7 years, p<0.001), independent of stage. CONCLUSION: Patients with ARD and lung cancer had better OS compared with their counterparts, independent of cancer stage and treatments and were less likely to have advanced stage lung cancer at diagnosis. Additional studies are needed to investigate the differential immunological anti-tumour immune activity and genomic variations in patients with and without ARD.

Myocarditis in Patients With Idiopathic Inflammatory Myopathies: Clinical Presentation and Outcomes.

OBJECTIVE: To determine the clinical phenotype and outcomes of patients with idiopathic inflammatory myopathies (IIMs) and myocarditis. METHODS: Using the Johns Hopkins Myositis Center Research Registry, we identified 31 adult patients with IIM-out of a total of 3082 with confirmed or suspected muscle disease-with an encounter code of myocarditis from 2004 to 2021. Of these, 14 adult patients with IIM were adjudicated to have clinical myocarditis. Information about demographics, autoantibodies, and clinical outcomes was retrospectively collected and analyzed. RESULTS: Of 14 patients with IIM with clinical myocarditis, the median age at IIM diagnosis was 49 (IQR 35-56) years, and the median age at myocarditis diagnosis was 54 (IQR 36-61) years. The median duration between IIM diagnosis and myocarditis was 3 (IQR 2-9) years. The majority of patients were female (8/14, 57%) and Black (10/14, 71%). Antisynthetase syndrome was the most common IIM subtype (9/14, 64%). Anti-Jo1 (n = 4) and anti-PL12 (n = 3) were the most frequent autoantibodies. At myocarditis diagnosis, most patients (11/14, 79%) had active myositis, defined as elevated creatine kinase and/or muscle weakness; required hospitalization (13/14, 93%); and had reduced left ventricular ejection fraction (LVEF < 50%; 10/14, 71%). Despite intensification of immunosuppression, the 5-year overall survival rate from IIM diagnosis was 84%, and the 5-year overall survival rate from myocarditis diagnosis was 53%. Systolic dysfunction (LVEF < 40%) at final evaluation was observed in all expired patients (n = 6). CONCLUSION: Clinical presentations of myocarditis in this select cohort of patients with IIM were severe and heterogeneous with poor outcomes despite intensification of immunosuppression, potentially reflecting late detection of myocarditis.

Diagnostic Yield of Computed Tomography for Cancer Detection in a Tertiary Referral Population of Idiopathic Inflammatory Myositis Patients.

OBJECTIVE: To inform guidance for cancer detection in patients with idiopathic inflammatory myopathy (IIM), we evaluated the diagnostic yield of computed tomography (CT) imaging for cancer screening/surveillance within distinct IIM subtypes and myositis-specific autoantibody strata. METHODS: We conducted a single-center, retrospective cohort study in IIM patients. Overall diagnostic yield (number of cancers diagnosed/number of tests performed), percentage of false positives (number of biopsies performed not leading to cancer diagnosis/number of tests performed), and test characteristics were determined on CT of the chest and abdomen/pelvis. RESULTS: Within the first 3 years since IIM symptom onset, a total of 9 of 1,011 (0.9%) chest CT scans and 12 of 657 (1.8%) abdomen/pelvis CT scans detected cancer. Diagnostic yields for both CT of the chest and CT of the abdomen/pelvis were highest in dermatomyositis, specifically anti-transcription intermediary factor 1γ (2.9% and 2.4% for CT of the chest and abdomen/pelvis, respectively). The highest percentage of false positives was in patients with antisynthetase syndrome (ASyS) (4.4%) and immune-mediated necrotizing myopathy (4.4%) on CT of the chest, and ASyS (3.8%) on CT of the abdomen/pelvis. Patients ages <40 years old at IIM onset had both low diagnostic yields (0% and 0.5%) and high false-positive rates (1.9% and 4.4%) for CT of the chest and abdomen/pelvis, respectively. CONCLUSION: In a tertiary referral cohort of IIM patients, CT imaging has a wide range of diagnostic yield and frequency of false positives for contemporaneous cancer. These findings suggest that cancer detection strategies targeted according to IIM subtype, autoantibody positivity, and age may maximize cancer detection while minimizing the harms and costs of over-screening.

Association of Anti-CCAR1 Autoantibodies With Decreased Cancer Risk Relative to the General Population in Patients With Anti-Transcriptional Intermediary Factor 1γ-Positive Dermatomyositis.

OBJECTIVE: To describe the disease specificity, clinical phenotype, and risk of cancer in dermatomyositis (DM) patients with autoantibodies against cell division cycle and apoptosis regulator protein 1 (anti-CCAR1). METHODS: The frequency of anti-CCAR1 autoantibodies was measured by enzyme-linked immunosorbent assay in the serum of DM patients from 2 independent cohorts (Johns Hopkins and Stanford), with patients with several other rheumatic diseases and healthy controls used as comparators. Clinical features and the risk of cancer incidence relative to that in the general population were determined in anti-CCAR1-positive DM patients. RESULTS: Anti-CCAR1 antibodies were significantly associated with anti-transcriptional intermediary factor 1γ (anti-TIF1γ) antibodies present in the serum of patients with DM: 80 (32%) of 252 anti-TIF1γ-positive DM patients versus 14 (8%) of 186 anti-TIF1γ-negative DM patients were positive for anti-CCAR1 antibodies (P < 0.001). Anti-CCAR1 antibodies were not detected in any of the 32 serum samples from healthy controls, and were present at very low frequencies in the sera of patients with other rheumatic diseases: 1 (2.3%) of 44 patients with anti-hydroxymethylglutaryl-coenzyme A reductase-positive necrotizing myopathy, 1 (2.3%) of 44 patients with inclusion body myositis, and 3 (6.5%) of 46 patients with systemic lupus erythematosus were positive for anti-CCAR1 antibodies. Upon examining data on occurrence of cancer from the onset of DM onward, the observed number of cancers diagnosed in anti-TIF-1γ-positive DM patients was significantly greater than expected in both cohorts, with a standardized incidence ratio (SIR) of 3.49 (95% confidence interval [95% CI] 2.39-4.92) in the Johns Hopkins cohort and a SIR of 4.54 (95% CI 3.04-6.52) in the Stanford cohort (each P < 0.001). DM patients who were both anti-TIF1γ positive and anti-CCAR1 positive had lower SIRs for cancer, with a SIR of 1.78 (95% CI 0.77-3.51) (P = 0.172) in the Johns Hopkins cohort and a SIR of 1.61 (95% CI 0.44-4.13) (P = 0.48) in the Stanford cohort. CONCLUSION: Anti-CCAR1 autoantibodies are specific for anti-TIF1γ-positive DM. Their presence in anti-TIF1γ-positive patients attenuates the risk of cancer to a level comparable to that seen in the general population.

Anti-MDA5-positive dermatomyositis and remission in a single referral centre population.

OBJECTIVES: To describe a single-centre North American adult cohort of anti-MDA5-positive dermatomyositis patients, with emphasis on drug-free long-term remission. METHODS: We conducted an observational retrospective cohort study of anti-MDA5-positive DM patients. All consented patients seen in the Johns Hopkins Myositis Centre from 2003-2020 with suspected muscle disease were routinely screened for myositis-specific autoantibodies. All sera were screened for anti-MDA5 autoantibodies by line blot; positives were verified by enzyme-linked immunoassay. Patients whose sera were anti-MDA5 positive by both assays (n=52) were followed longitudinally. If clinical status was unavailable, structured telephone interviews were conducted. Clinical remission was defined as being off all immunosuppression >1 year while remaining asymptomatic. RESULTS: 38/52 (73%) of the patients were women with a median age at disease-onset of 47 (IQR 40-54). Twenty-five of the patients (48%) were White, 16 (30%) were Black and 3 (6%) were Asian. Most patients (42/52, 80%) had interstitial lung disease, defined by inflammatory or fibrotic changes on high resolution computed tomography (HRCT). 18/52 (35%) of patients required pulse-dose methylprednisolone, 4/52 (8%) experienced spontaneous pneumothorax/pneumomediastinum, 6/52 (12%) required intubation, and 5/52 (10%) died. Over longitudinal follow-up (median 3.5 years), 9 (18%) patients achieved clinical remission. The median time from symptom onset to clinical remission was 4 years, and the median duration of sustained remission was 3.5 years (range 1.4-7.8). No demographic or disease characteristics were significantly associated with remission. CONCLUSIONS: In this single centre, tertiary referral population of anti-MDA5-positive dermatomyositis, ~20% of patients experienced long-term drug-free remission after a median disease duration of 4 years. No clinical or biologic factors were associated with clinical remission.

Clinical Subgroups and Factors Associated With Progression in Patients With Inclusion Body Myositis.

BACKGROUND AND OBJECTIVES: Sporadic inclusion body myositis (IBM) is the most common acquired myopathy in individuals older than 50 years. The disorder is slowly progressive, and although many therapies have been investigated, response has generally been poor. Clinical heterogeneity may influence treatment responsiveness; however, data regarding heterogeneity in IBM are limited and often conflicting. We aim to identify clinically distinct subgroups within a large IBM cohort and prognostic factors for disease progression. METHODS: Clinical, histologic, radiologic, and electrophysiologic data were analyzed for all patients with IBM and other forms of myositis enrolled in a longitudinal cohort from The Johns Hopkins Myositis Center from 2003 to 2018. Patients with IBM were included if they met at least one of the following criteria: Griggs possible, European Neuromuscular Centre 2011 probable, or Lloyd-Greenberg data-derived criteria for IBM. Univariate, multivariate, and graphical analyses were used to identify prognostic factors in patients with IBM. Thus, linear and logistic regressions were used to adjust for potential confounding variables. The evolution of creatine kinase and muscle strength was studied using multilevel linear regression models. Nonmodifiable risk factors (sex, race, disease duration, and age at the onset of first symptoms) were used as adjusting covariates for the regression analyses. RESULTS: Among the 335 patients meeting the inclusion criteria for IBM, 64% were male with an average age of disease onset of 58.7 years and delay to diagnosis of 5.2 years. Initial misdiagnosis (52%) and immunosuppressant treatment (42%) were common. Less than half (43%) of muscle biopsies demonstrated all 3 pathologic hallmarks: endomysial inflammation, mononuclear cell invasion, and rimmed vacuoles. Black patients had significantly weaker arm abductors, hip flexors, and knee flexors compared with non-Black patients. Female patients had stronger finger flexors and knee extensors compared with their male counterparts. Younger age (<50 years) at onset was not associated with increased weakness. DISCUSSION: Our study demonstrates that female and Black patients have distinct clinical phenotypes and trajectories within the overarching IBM clinical phenotype. These subgroups may have different responses to therapies, which may influence the design of future clinical trials in IBM.

Reliability and validity of PROMIS physical function, pain interference, and fatigue as patient reported outcome measures in adult idiopathic inflammatory myopathies: International study from the OMERACT myositis working group.

OBJECTIVE: Pain interference, fatigue, and impaired physical function are common features of idiopathic inflammatory myopathies (IIM). The objective of this study was to evaluate the construct validity and test-retest reliability of the Patient Reported Outcome Information System (PROMIS) Pain Interference 6av1.0, Fatigue 7av1.0, and Physical Function 8bv2.0 instruments. METHODS: Patient-Reported Outcome Measures (PROMs) were deployed to adult IIM patients from OMERACT Myositis Working Group (MWG) international clinic sites via two online surveys (2019, 2021). Internal consistency of each PROM was analyzed by Cronbach's α. Construct validity was determined by a priori hypotheses generated by the MWG with >75% agreement for each hypothesis and calculated with Pearson correlations. Test-retest reliability was assessed using intraclass correlation coefficient with PROMIS instruments administered at time zero and 7 days. RESULTS: Surveys were sent to 368 participants in total; participants who completed each questionnaire varied (n=65 to 263). For construct validity, 10 out of 13 a priori hypotheses were met supporting construct validity of PROMIS instruments (Pain Interference 3/4, fatigue 4/4, and Physical Function 3/5). Test-retest reliability was strong for all PROMIS instruments. All PROMIS instruments demonstrated excellent internal consistency. None of the measures demonstrated any ceiling or floor effects except for a ceiling effect in the Pain Interference instrument. CONCLUSIONS: This study presents test-retest reliability and construct validity evidence supporting PROMIS Pain Interference (6a v1.0), Fatigue (7a v1.0), and Physical Function (8b v2.0) using a large international cohort of patients with IIM. Internal consistency of these instruments was excellent. A ceiling effect was noted in the Pain Interference instrument.

Coexisting autoantibodies against transcription factor Sp4 are associated with decreased cancer risk in patients with dermatomyositis with anti-TIF1γ autoantibodies.

OBJECTIVES: In dermatomyositis (DM), autoantibodies are associated with unique clinical phenotypes. For example, anti-TIF1γ autoantibodies are associated with an increased risk of cancer. The purpose of this study was to discover novel DM autoantibodies. METHODS: Phage ImmunoPrecipitation Sequencing using sera from 43 patients with DM suggested that transcription factor Sp4 is a novel autoantigen; this was confirmed by showing that patient sera immunoprecipitated full-length Sp4 protein. Sera from 371 Johns Hopkins patients with myositis (255 with DM, 28 with antisynthetase syndrome, 40 with immune-mediated necrotising myopathy, 29 with inclusion body myositis and 19 with polymyositis), 80 rheumatological disease controls (25 with Sjogren's syndrome, 25 with systemic lupus erythematosus and 30 with rheumatoid arthritis (RA)) and 200 healthy comparators were screened for anti-SP4 autoantibodies by ELISA. A validation cohort of 46 anti-TIF1γ-positive patient sera from the University of Pittsburgh was also screened for anti-Sp4 autoantibodies. RESULTS: Anti-Sp4 autoantibodies were present in 27 (10.5%) patients with DM and 1 (3.3%) patient with RA but not in other clinical groups. In patients with DM, 96.3% of anti-Sp4 autoantibodies were detected in those with anti-TIF1γ autoantibodies. Among 26 TIF1γ-positive patients with anti-Sp4 autoantibodies, none (0%) had cancer. In contrast, among 35 TIF1γ-positive patients without anti-Sp4 autoantibodies, 5 (14%, p=0.04) had cancer. In the validation cohort, among 15 TIF1γ-positive patients with anti-Sp4 autoantibodies, 2 (13.3%) had cancer. By comparison, among 31 TIF1γ-positive patients without anti-Sp4 autoantibodies, 21 (67.7%, p<0.001) had cancer. CONCLUSIONS: Anti-Sp4 autoantibodies appear to identify a subgroup of anti-TIF1γ-positive DM patients with lower cancer risk.

Subsets of Idiopathic Inflammatory Myositis Enriched for Contemporaneous Cancer Relative to the General Population.

OBJECTIVE: This study investigates cancer risk in idiopathic inflammatory myopathy (IIM) relative to the general population. METHODS: We conducted a single-center, retrospective cohort study of IIM patients and malignancy. Myositis-specific and -associated autoantibodies were determined by Euroimmun line blot, enzyme-linked immunosorbent assay, and immunoprecipitation. We calculated standardized prevalence ratios (SPRs) and adjusted for calendar year, age, sex, race, and ethnicity by comparing observed cancers in IIM patients versus expected cancers in the general population using the Surveillance, Epidemiology, and End Results registry. RESULTS: Of 1,172 IIM patients, 203 (17%) patients with a cancer history were studied. Over a median follow-up of 5.2 years, the observed number of IIM patients diagnosed with cancer was increased 1.43-fold (SPR 1.43 [95% confidence interval (95% CI) 1.15-1.77]; P = 0.002). Within 3 years of IIM symptom onset, an increased SPR was observed for anti-transcription intermediary factor 1γ (anti-TIF1γ)-positive patients for ovarian and breast cancer (ovarian SPR 18.39 [95% CI 5.01-47.08], P < 0.001; breast SPR 3.84 [95% CI 1.99-6.71], P < 0.001). As expected, anti-TIF1γ positivity was associated with a significantly elevated SPR; however, only 55% (36 of 66) of all cancers within 3 years of dermatomyositis onset were observed in anti-TIF1γ-positive patients. Other myositis-specific autoantibodies, including anti-Mi-2, anti-small ubiquitin-like modifier activating enzyme (SAE), and anti-nuclear matrix protein 2 (NXP-2), accounted for 26% (17 of 66) of cancers diagnosed within 3 years of dermatomyositis onset. No cancer association, positive or negative, was observed for patients with antisynthetase, anti-melanoma differentiation-associated protein 5 (anti-MDA-5), or anti-hydroxymethylglutaryl-coenzyme A reductase (anti-HMGCR) antibodies. CONCLUSION: In a tertiary referral center population, anti-TIF1γ was most strongly associated with breast and ovarian cancer. Patients with antisynthetase, anti-MDA-5, or anti-HMGCR antibodies had the same cancer risk as the general population.

Rapidly progressive interstitial lung disease in patients with anti-melanoma differentiation-associated gene 5-positive dermatomyositis: serial changes on HRCT.

BACKGROUND: Anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibodies in patients with dermatomyositis are associated with rapidly progressive interstitial lung disease (RP-ILD). Computed tomography (CT) plays a central role in the diagnosis of RP-ILD and may help characterize the temporal changes. METHODS: We report five anti-MDA5-positive dermatomyositis patients with serial CT scans spanning their acute RP-ILD disease course. RESULTS: Our case series highlights the variable imaging pattern that can manifest in this setting, including diffuse alveolar damage and nonspecific interstitial pneumonia patterns. Three patients in our series died within 4 months of their disease onset, whereas the other two patients survived. CONCLUSION: The serial CT changes in anti-MDA5 disease are dynamic and variable; therefore, it is imperative to maintain a broad differential when faced with these HRCT patterns to improve the diagnosis and management of this underrecognized entity.

The DNA sensors AIM2 and IFI16 are SLE autoantigens that bind neutrophil extracellular traps.

Background: Nucleic acid binding proteins are frequently targeted as autoantigens in systemic lupus erythematosus (SLE) and other interferon (IFN)-linked rheumatic diseases. The AIM-like receptors (ALRs) are IFN-inducible innate sensors that form supramolecular assemblies along double-stranded (ds)DNA of various origins. Here, we investigate the ALR absent in melanoma 2 (AIM2) as a novel autoantigen in SLE, with similar properties to the established ALR autoantigen interferon-inducible protein 16 (IFI16). We examined neutrophil extracellular traps (NETs) as DNA scaffolds on which these antigens might interact in a pro-immune context. Methods: AIM2 autoantibodies were measured by immunoprecipitation in SLE and control subjects. Neutrophil extracellular traps were induced in control neutrophils and combined with purified ALR proteins in immunofluorescence and DNase protection assays. SLE renal tissues were examined for ALR-containing NETs by confocal microscopy. Results: AIM2 autoantibodies were detected in 41/131 (31.3%) SLE patients and 2/49 (4.1%) controls. Our SLE cohort revealed a frequent co-occurrence of anti-AIM2, anti-IFI16, and anti-DNA antibodies, and higher clinical measures of disease activity in patients positive for antibodies against these ALRs. We found that both ALRs bind NETs in vitro and in SLE renal tissues. We demonstrate that ALR binding causes NETs to resist degradation by DNase I, suggesting a mechanism whereby extracellular ALR-NET interactions may promote sustained IFN signaling. Conclusions: Our work suggests that extracellular ALRs bind NETs, leading to DNase resistant nucleoprotein fibers that are targeted as autoantigens in SLE. Funding: These studies were funded by NIH R01 DE12354 (AR), P30 AR070254, R01 GM 129342 (JS), K23AR075898 (CM), K08AR077100 (BA), the Jerome L. Greene Foundation and the Rheumatology Research Foundation. Dr. Antiochos and Dr. Mecoli are Jerome L. Greene Scholars. The Hopkins Lupus Cohort is supported by NIH grant R01 AR069572. Confocal imaging performed at the Johns Hopkins Microscopy Facility was supported by NIH Grant S10 OD016374.

Systemic lupus erythematosus (SLE or lupus for short) is an autoimmune disease in which the immune system attacks healthy tissue in organs across the body. The cause is unknown, but people with the illness make antibodies that stick to proteins that are normally found inside the cell nucleus, where DNA is stored. To make these antibodies, the immune system must first 'see' these proteins and mistakenly recognise them as a threat. But how does the immune system recognise proteins that are normally hidden inside cells? During infection, a type of immune cell called a neutrophil releases DNA from its nucleus to form structures called neutrophil extracellular traps, or NETs for short. The role of these NETs is to capture and kill pathogens, but they also expose the neutrophil's DNA and the proteins attached to it to other immune cells. It is therefore possible that other immune cells interacting with NETs during infection may contribute to the development of lupus. Two proteins of interest are AIM2 and IFI16. These proteins form large, shield-like structures around strands of DNA, and previous work has shown that some people with lupus make antibodies against IFI16. Antiochos et al. wondered whether IFI16 and AIM2 might stick to NETs, exposing themselves to the immune system. Examining the blood of people with lupus revealed that one in three of them made antibodies that could stick to AIM2. Those people were also more likely to have antibodies that could stick to IFI16 and to strands of DNA. Using microscopy, Antiochos et al. also found AIM2 and IFI16 on NETs in the kidneys of some people with lupus. Further investigation showed that the presence of AIM2 and IFI16 prevents NETs from breaking down. If proteins like AIM2 and IFI16 can stop NETs from breaking down, they could allow the immune system more time to develop antibodies against them. Further investigation could reveal whether this is one of the causes of lupus. A clearer understanding of the antibodies could also boost research into diagnosis and treatment.

Presence and Implications of Anti-Angiotensin Converting Enzyme-2 Immunoglobulin M Antibodies in Anti-Melanoma-Differentiation-Associated 5 Dermatomyositis.

OBJECTIVE: Patients with anti-melanoma-differentiation-associated 5 (anti-MDA5)-positive dermatomyositis (DM) share several striking similarities to patients with SARS-CoV-2. Our objective was to assess the prevalence of anti-angiotensin converting enzyme-2 (ACE2) immunoglobulin M (IgM) antibodies, found in patients with severe SARS-CoV-2, in two independent anti-MDA5-positive DM cohorts. METHODS: Anti-ACE2 IgM antibodies were assayed by enzyme-linked immunosorbent assay (ELISA) in two anti-MDA5-positive DM cohorts: a predominantly outpatient North American cohort (n = 52) and a Japanese cohort enriched for new-onset disease (n = 32). Additionally, 118 patients with SARS-CoV-2 with a spectrum of clinical severity were tested for anti-MDA5 antibodies by ELISA. RESULTS: Five of fifty-two (9.6%) North American patients and five of thirty-two (15%) Japanese patients were positive for anti-ACE2 IgM. In the North American cohort, all five patients with anti-ACE2 IgM antibodies had proximal muscle weakness, had interstitial lung disease, were significantly more likely to receive pulse dose methylprednisolone (80% vs 30%, P = 0.043), and had worse forced vital capacity (median 59% predicted vs 78%, P = 0.056) compared with the anti-ACE2-IgM-negative group. In the Japanese cohort, all five anti-ACE2-IgM-positive patients also required pulse dose methylprednisolone, and three of five (60%) patients died. Japanese patients with anti-ACE2 IgM had significantly worse oxygenation, as defined by a lower partial pressure of oxygen (PaO2)/fraction of inspired oxygen (FiO2) ratio (233 vs 390, P = 0.021), and a higher alveolar-arterial oxygenation gradient (91 vs 23 mm Hg, P = 0.024) than the IgM-negative group. CONCLUSION: We describe anti-ACE2 IgM autoantibodies in two independent cohorts with anti-MDA5-positive DM. These autoantibodies may be biomarkers for severe disease and provide insight into disease pathogenesis.

IgM anti-ACE2 autoantibodies in severe COVID-19 activate complement and perturb vascular endothelial function.

BackgroundSome clinical features of severe COVID-19 represent blood vessel damage induced by activation of host immune responses initiated by the coronavirus SARS-CoV-2. We hypothesized autoantibodies against angiotensin-converting enzyme 2 (ACE2), the SARS-CoV-2 receptor expressed on vascular endothelium, are generated during COVID-19 and are of mechanistic importance.MethodsIn an opportunity sample of 118 COVID-19 inpatients, autoantibodies recognizing ACE2 were detected by ELISA. Binding properties of anti-ACE2 IgM were analyzed via biolayer interferometry. Effects of anti-ACE2 IgM on complement activation and endothelial function were demonstrated in a tissue-engineered pulmonary microvessel model.ResultsAnti-ACE2 IgM (not IgG) autoantibodies were associated with severe COVID-19 and found in 18/66 (27.2%) patients with severe disease compared with 2/52 (3.8%) of patients with moderate disease (OR 9.38, 95% CI 2.38-42.0; P = 0.0009). Anti-ACE2 IgM autoantibodies were rare (2/50) in non-COVID-19 ventilated patients with acute respiratory distress syndrome. Unexpectedly, ACE2-reactive IgM autoantibodies in COVID-19 did not undergo class-switching to IgG and had apparent KD values of 5.6-21.7 nM, indicating they are T cell independent. Anti-ACE2 IgMs activated complement and initiated complement-binding and functional changes in endothelial cells in microvessels, suggesting they contribute to the angiocentric pathology of COVID-19.ConclusionWe identify anti-ACE2 IgM as a mechanism-based biomarker strongly associated with severe clinical outcomes in SARS-CoV-2 infection, which has therapeutic implications.FUNDINGBill & Melinda Gates Foundation, Gates Philanthropy Partners, Donald B. and Dorothy L. Stabler Foundation, and Jerome L. Greene Foundation; NIH R01 AR073208, R01 AR069569, Institutional Research and Academic Career Development Award (5K12GM123914-03), National Heart, Lung, and Blood Institute R21HL145216, and Division of Intramural Research, National Institute of Allergy and Infectious Diseases; National Science Foundation Graduate Research Fellowship (DGE1746891).

Perifollicular Hypopigmentation in Systemic Sclerosis: Associations With Clinical Features and Internal Organ Involvement.

OBJECTIVE: To determine whether perifollicular hypopigmentation in systemic sclerosis (SSc) is associated with demographics, distinct clinical features, and autoantibody profiles. METHODS: Patients with SSc were prospectively enrolled, with a standardized data form used to collect anatomic distribution of perifollicular hypopigmentation. Associations between hypopigmentation and features of SSc were assessed. RESULTS: Of 179 adult patients with SSc, 36 (20%) patients had perifollicular hypopigmentation. Of these 36 patients, 94% (n = 34) were female and 33% (n = 12) had limited cutaneous SSc. In univariable logistic regression, Black race (odds ratio [OR] 15.63, 95% CI 6.6-37.20, P < 0.001), diffuse cutaneous SSc (dcSSc; OR 4.62, 95% CI 2.11-10.09, P < 0.001), higher maximum modified Rodnan skin score (mRSS; OR 1.05, 95% CI 1.02-1.08, P = 0.003), myopathy (OR 3.92, 95% CI 1.80-8.57, P < 0.001), pulmonary fibrosis (OR 2.69, 95% CI 1.20-6.02, P = 0.02), lower minimum forced vital capacity % predicted (OR 0.96, 95% CI 0.94-0.99, P = 0.001), and lower minimum diffusing capacity for carbon monoxide % predicted (OR 0.97, 95% CI 0.95-0.99, P = 0.009) were associated with hypopigmentation. Anticentromere antibodies inversely associated with hypopigmentation (OR 0.24, 95% CI 0.07-0.86, P = 0.03). After adjusting for age, race, and disease duration, dcSSc (OR 4.28, 95% CI 1.46-12.53, P = 0.008) and increased mRSS (OR 1.07, 95% CI 1.02-1.12, P = 0.009) were significantly associated with hypopigmentation. CONCLUSION: Perifollicular hypopigmentation is observed in a subset of patients with SSc and associated with diffuse subtype. Larger prospective studies determining whether perifollicular hypopigmentation precedes end-organ involvement and whether specific patterns associate with internal organ involvement are needed.