Faculty Bibliography

OBJECTIVE:Using the Manhattan Lupus Surveillance Program (MLSP), a multi-racial/ethnic population-based registry, we compared three commonly used classification criteria for Systemic Lupus Erythematosus (SLE) to identify unique cases and determine the incidence and prevalence of SLE using the EULAR/ACR criteria. METHODS:SLE cases were defined as fulfilling 1997 ACR, SLICC, or EULAR/ACR classification criteria. We quantified the number of cases uniquely associated with each and the number fulfilling all three. Prevalence and incidence using the EULAR/ACR classification criteria and associated 95% confidence intervals (CI) were calculated. RESULTS:1,497 cases fulfilled at least one of the three classification criteria, with 1,008 (67.3%) meeting all three classifications, 138 (9.2%) fulfilling only SLICC criteria, 35 (2.3%) fulfilling only ACR criteria and 34 (2.3%) uniquely fulfilling EULAR/ACR criteria. Patients solely satisfying EULAR/ACR criteria had fewer than four manifestations. The majority classified only by the ACR criteria did not meet any of the defined immunologic criteria. Patients fulfilling only SLICC criteria did so based on the presence of features unique to this system. Using the EULAR/ACR classification criteria, age-adjusted overall prevalence and incidence rates of SLE in Manhattan were 59.6 (95%CI:55.9-63.4) and 4.9 (95%CI 4.3-5.5) per 100,000 population, with age-adjusted prevalence and incidence rates highest among non-Hispanic Black females. CONCLUSION/CONCLUSIONS:Applying the three commonly used classification criteria to a population-based registry identified patients with SLE fulfilling only one validated definition. The most recently developed EULAR/ACR classification criteria revealed similar prevalence and incidence estimates to those previously established for the ACR and SLICC classification schemes.

BACKGROUND:The clinical heterogeneity of SLE with its complex pathogenesis remains challenging as we strive to provide optimal management. The contribution of platelets to endovascular homeostasis, inflammation and immune regulation highlights their potential importance in SLE. Prior work from our group showed that the Fcγ receptor type IIa (FcγRIIa)-R/H131 biallelic polymorphism is associated with increased platelet activity and cardiovascular risk in SLE. The study was initiated to investigate the platelet transcriptome in patients with SLE and evaluate its association across FcγRIIa genotypes and distinct clinical features. METHODS:Fifty-one patients fulfilling established criteria for SLE (mean age = 41.1 ± 12.3, 100% female, 45% Hispanic, 24% black, 22% Asian, 51% white, mean SLEDAI = 4.4 ± 4.2 at baseline) were enrolled and compared with 18 demographically matched control samples. The FCGR2a receptor was genotyped for each sample, and RNA-seq was performed on isolated, leukocyte-depleted platelets. Transcriptomic data were used to create a modular landscape to explore the differences between SLE patients and controls and various clinical parameters in the context of FCGR2a genotypes. RESULTS:There were 2290 differentially expressed genes enriched for pathways involved in interferon signaling, immune activation, and coagulation when comparing SLE samples vs controls. When analyzing patients with proteinuria, modules associated with oxidative phosphorylation and platelet activity were unexpectedly decreased. Furthermore, genes that were increased in SLE and in patients with proteinuria were enriched for immune effector processes, while genes increased in SLE but decreased in proteinuria were enriched for coagulation and cell adhesion. A low-binding FCG2Ra allele (R131) was associated with decreases in FCR activation, which further correlated with increases in platelet and immune activation pathways. Finally, we were able to create a transcriptomic signature of clinically active disease that performed significantly well in discerning SLE patients with active clinical disease form those with inactive clinical disease. CONCLUSIONS:In aggregate, these data demonstrate the platelet transcriptome provides insight into lupus pathogenesis and disease activity, and shows potential use as means of assessing this complex disease using a liquid biopsy.

OBJECTIVES/OBJECTIVE:Autoantibody seroconversion has been extensively studied in the context of COVID-19 infection but data regarding post-vaccination autoantibody production is lacking. Here we aimed to determine the incidence of common autoantibody formation following mRNA COVID-19 vaccines in patients with inflammatory arthritis (IA) and in healthy controls. METHODS:Autoantibody seroconversion was measured by serum ELISA in a longitudinal cohort of IA participants and healthy controls before and after COVID-19 mRNA-based immunization. RESULTS:Overall, there was a significantly lower incidence of ANA seroconversion in participants who did not contract COVID-19 prior to vaccination compared with those who been previously infected (7.4% vs 24.1%, p= 0.014). Incidence of de novo anti-cyclic citrullinated protein (CCP) seroconversion in all participants was low at 4.9%. Autoantibody levels were typically of low titer, transient, and not associated with increase in IA flares. CONCLUSIONS:In both health and inflammatory arthritis, the risk of autoantibody seroconversion is lower following mRNA-based immunization than following natural SARS-CoV-2 infection. Importantly, seroconversion does not correlate with self-reported IA disease flare risk, further supporting the encouragement of mRNA-based COVID-19 immunization in the IA population.

OBJECTIVE:Delayed detection of lupus nephritis associates with worse outcomes. There are conflicting recommendations regarding a threshold level of proteinuria at which biopsy will likely yield actionable management. This study addressed the association of urine protein creatinine ratios (UPCR) with clinical characteristics and investigated the incidence of proliferative and membranous histology in patients with a UPCR between 0.5 and 1. METHODS:275 SLE patients (113 first biopsy, 162 repeat) were enrolled in the multicentre multi-ethnic/racial Accelerating Medicines Partnership across 15 U.S. sites at the time of a clinically indicated renal biopsy. Patients were followed for 1 year. RESULTS:At biopsy, 54 patients had UPCR <1 and 221 had UPCR >1. Independent of UPCR or biopsy number, a majority (92%) of patients had class III, IV, V or mixed histology. Moreover, patients with UPCR <1 and class III, IV, V, or mixed had a median activity index of 4.5 and chronicity index of 3, yet 39% of these patients had an inactive sediment. Neither anti-dsDNA nor low complement distinguished class I or II from III, IV, V, or mixed in patients with UPCR <1. Of 29 patients with baseline UPCR <1 and class III, IV, V or mixed, 23 (79%) had a UPCR <0.5 at one year. CONCLUSION/CONCLUSIONS:In this prospective study three quarters of patients with UPCR <1 had histology showing class III, IV, V or mixed with accompanying activity and chronicity despite an inactive sediment or normal serologies. These data support renal biopsy at thresholds lower than a UPCR of 1.

Background/Purpose: Lupus nephritis (LN) is characterized by considerable variability in its clinical manifestations and histopathological findings. Understanding the cellular and molecular mechanisms underlying this heterogeneity is key for the development of personalized treatments for LN.
Method(s): Droplet-based single-cell RNA-sequencing was applied to the analysis of dissociated kidney samples, collected from 155 LN patients with active kidney disease and 30 living donor controls as part of a large-scale, multi-center study. 73,440 immune cells passing quality control were identified, spanning 134 cell subsets, representing various populations of tissue-resident and infiltrating leukocytes, as well as the activation states these cells assume as part of their diseaserelated activation and differentiation (Fig. 1). Principal component analysis (PCA) was used to characterize the variability in cell subset frequencies across the LN patients. Relationships between the resulting principal components (PCs) and the demographic, clinical and histopathological features of the patients were then assessed. Figure 1. Single-cell RNA-sequencing was used to profile immune cells isolated from the kidneys of LN patients and healthy controls. Five main lineages of cells were identified, as shown in a Uniform Manifold Approximation and Projection (UMAP) plot: myeloid cells, T/NK cells, B cells, plasma cells and dividing cells. The cells of each lineage were further split into finer subsets of cells (color-coded).
Result(s): The first PC (PC1), explaining 33% of the total variability in cell subset frequencies, reflected the balance between lymphocytes and monocytes/macrophages. The second PC (PC2), explaining an additional 21% of the total variability, represented the degree of macrophage differentiation to an alternatively activated phagocytic profile. The third and fourth PCs, bringing the total explained variability to 74%, were related to the balance between cell-mediated and humoral immune responses. PC1 was significantly correlated with the Chronicity index, such that patients with a higher percentage of lymphocytes compared to monocytes/macrophages had a higher Chronicity score (rho =-0.439, p-value < 0.001; Fig. 2A). A high degree of macrophage differentiation, as represented by PC2, was associated with a high Activity score (rho =-0.495, p-value < 0.001; Fig. 2B), and, in addition, with proliferative or mixed histology class, compared to pure membranous nephritis (p-value = 0.001, Kruskal-Wallis test). We further identified a significant correlation of these PCs with age; specifically, older patients had a higher relative frequency of lymphocytes compared to monocytes/macrophages, a lesser degree of macrophage differentiation, and a higher representation of cells putatively involved in a humoral immune response compared to a cell-mediated one.
Conclusion(s): These results identify distinct leukocyte populations active in different LN patients and, possibly, different stages of disease, and suggest potential therapeutic targets, that must be validated in mechanistic studies. This approach may pave the way to personalized treatment of LN

Background/Purpose: Patients with SLE may be at increased risk for developing a venous thromboembolism (VTE), particularly in the postpartum period. The Royal College of Obstetricians and Gynaecologists (RCOG) guideline for postpartum VTE prophylaxis is unique in its inclusion of "active" SLE as an actionable risk factor. In this guideline, a score >= 3 drives a formal recommendation for a 6-week prophylactic treatment course with enoxaparin. Although not defined, "active" SLE alone scores 3 points. The inclusion of SLE raises concerns regarding appropriate attribution and subsequent management decisions. The current study applied the RCOG model to a cohort of postpartum SLE patients to determine whether these patients a) qualify as having "active" SLE b) have other risk factors for VTE c) received the recommended prophylaxis and d) had a postpartum VTE.
Method(s): The retrospective study comprised 55 pregnancies in 49 patients fulfilling criteria for classification of SLE based on ACR, SLICC or EULAR/ACR definitions consecutively seen over the last 5 years. Disease activity at delivery was assessed by the SLEPDAI using SELENA and Hybrid SELENA definitions for scoring proteinuria. Remission was assigned by applying the DORIS (Definitions of Remission in SLE) criteria. Patients not in remission were considered to have "active" SLE, even if a low level with only one clinical domain scored. RCOG scoring was calculated for each patient prior to and after delivery.
Result(s): The median age was 32 years (IQR 29-36 years) and the median BMI was 26.6 kg/m2 (IQR 23.0-30.9 kg/m2), with 49.1% African-American, 16.4% Asian, 29.1% White, 5.5% Other and 32.7% of Hispanic ethnicity. The median SELENA and Hybrid SELENA SLEPDAI scores were 2.0 (IQR 0-6) and 2.0 (IQR 0-5) respectively. The components of the RCOG model with each of its elements scored for the cohort (Table 1). 34 pregnancies (61.8%) were in DORIS remission throughout pregnancy. 21 (38.2%) were not in DORIS remission at delivery and received 3 points on the RCOG model, since by not achieving remission their SLE could be considered at least mildly active. Of these pregnancies, only 19% were recommended for VTE prophylaxis despite RCOG score >= 3. Only 35.7% of pregnancies in DORIS remission, but with 3 points for non-SLE related VTE risk factors, were recommended for VTE prophylaxis (Table 2). Of the 20 pregnancies in remission with an RCOG score < 3 after assessing all risk factors, 15% were nevertheless recommended for VTE prophylaxis. In contrast, of the 14 inactive pregnancies with RCOG score >= 3 for non-SLE activity factors, only 35.7% were recommended for VTE prophylaxis. No patients had a postpartum VTE regardless of therapy.
Conclusion(s): These data reveal that even for SLE patients in remission at the time of delivery, points for SLE alone should not automatically be assigned on the RCOG model. However, those who are in remission may still warrant VTE prophylaxis if other non-SLE related risk factors are present. Although no patient had a postpartum VTE, prophylactic anticoagulation should be instituted only when clinically appropriate. The healthcare team should carefully consider disease activity before applying 3 points for the diagnosis of SLE

BACKGROUND:Complement activation has been associated with adverse pregnancy outcomes (APO) in SLE. Pregnant women with SLE were studied to evaluate whether complement dysregulation within the first two pregnancy trimesters predicts APO. METHODS:Pregnant women fulfilled classification criteria for SLE. APO included neonatal death, preterm delivery before 36 weeks and small for gestational age newborn. Pre-eclampsia was also evaluated. Erythrocyte complement receptor 1 (ECR1) and erythrocyte-bound C4d (EC4d) were measured by flow cytometry. Complement proteins C3 and C4 were measured by immunoturbidimetry and anti-double-stranded DNA by ELISA in serum. Statistical analysis consisted of t-test, confusion matrix-derived diagnostic analysis, and multivariate logistic regression. RESULTS:Fifty-one women had 57 pregnancies and 169 visits during the study. Baseline visits occurred mainly in the first (n=32) and second trimester (n=21). Fourteen (24.6%) pregnancies resulted in 21 APO with preterm delivery being the most common (n=10). ECR1 <5.5 net mean fluorescence intensity in the first trimester predicted APO with a diagnostic OR (DOR) of 18.33 (95% CI: 2.39 to 140.4; t-test p=0.04). Other individual biomarkers did not reach statistical significance. To estimate the likelihood of APO, we developed an algorithm that included the week of pregnancy, ECR1 and EC4d. From this algorithm, a Pregnancy Adversity Index (PAI) was calculated, and a PAI >0 indicated an elevated likelihood of pregnancy complications (DOR: 20.0 (95% CI: 3.64 to 109.97)). CONCLUSIONS:Low levels of ECR1 in early or mid-pregnancy are predictive of an APO. Incorporating the weeks of gestation and both ECR1 and EC4d generated a PAI, which further predicted serious pregnancy complications.