Faculty Bibliography

OBJECTIVE:The APS ACTION Registry studies long-term outcomes in persistently antiphospholipid antibody (aPL)-positive patients. Our primary objective was to determine whether clinically meaningful aPL profiles at baseline remain stable over time. Our secondary objectives were to determine (1) whether baseline characteristics differ between patients with stable and unstable aPL profiles, and (2) predictors of unstable aPL profiles over time. METHODS:-GPI) IgG/M ≥ 40 U. Stable aPL profile was defined as a clinically meaningful aPL profile in at least two-thirds of follow-up measurements. Generalized linear mixed models with logit link were used for primary objective analysis. RESULTS:= 0.002) the odds of an unstable aPL profile over time. CONCLUSION/CONCLUSIONS:Approximately 80% of our international cohort patients with clinically meaningful aPL profiles at baseline remain stable at a median follow-up of 5 years; triple aPL-positivity increase the odds of a stable aPL profile. These results will guide future validation studies of stored blood samples through APS ACTION Core Laboratories.

OBJECTIVE:Hydroxychloroquine (HCQ) is a mainstay of therapy in the treatment of SLE. The effect of HCQ on platelets and vascular health is uncertain. We investigated the relationship between HCQ use and dose with platelet activity, platelet transcriptomics and vascular health in patients with SLE. METHODS:Platelet aggregation, platelet mRNA expression and vascular health (sublingual capillary perfused boundary region (PBR), red blood cell filling (RBCF) and brachial artery reactivity testing) were analysed by HCQ use and dose. RESULTS:Among 132 subjects with SLE (age: 39.7±12.9 years, 97% female), 108 were on HCQ. SLE disease activity was similar between subjects on and off HCQ. Platelet aggregation in response to multiple agonists was significantly lower in patients on HCQ. There were inverse relationships between HCQ dose and gene expression pathways of platelet activity. Gene expression of P-selectin (SELP) was inversely correlated with HCQ dose (r=-0.41, p=0.003), which was validated at the protein level. Subjects on HCQ had improved vascular function correlating with HCQ dose as measured by lower PBR (r=-0.52, p=0.007), higher RBCF (r=0.55, p=0.004) and greater brachial artery reactivity (r=0.43, p=0.056). CONCLUSION/CONCLUSIONS:HCQ use was associated with decreased platelet activation and activation-related transcripts and improved vascular health in SLE.

OBJECTIVE:To characterize patients with Systemic Lupus Erythematosus (SLE) affected by COVID-19 and to analyze associations of comorbidities and medications on infection outcomes. METHODS:Patients with SLE and RT-PCR-confirmed COVID-19 were identified through an established New York University lupus cohort, query of two hospital systems, and referrals from rheumatologists. Data were prospectively collected via a web-based questionnaire and review of medical records. Baseline characteristics were obtained for all patients with COVID-19 to analyze risk factors for hospitalization. Data were also collected from asymptomatic patients and those with COVID-19-like symptoms who tested negative or were not tested. Statistical analyses were limited to confirmed COVID-19-positive patients. RESULTS:A total of 226 SLE patients were included: 41 patients with confirmed COVID-19; 19 patients who tested negative for COVID-19; 42 patients with COVID-19-like symptoms who did not get tested; and 124 patients who remained asymptomatic without testing. Of those SLE patients with COVID-19, 24 (59%) required hospitalization, four required intensive care unit-level of care, and four died. Hospitalized patients tended to be older, non-white, Hispanic, have higher BMI, history of nephritis, and at least one comorbidity. An exploratory (due to limited sample size) logistic regression analysis identified race, presence of at least one comorbidity, and BMI as independent predictors of hospitalization. CONCLUSION/CONCLUSIONS:In general, the variables predictive of hospitalization in our SLE patients were similar to those identified in the general population. Further studies are needed to understand additional risk factors for poor COVID-19 outcomes in patients with SLE.

Background/Purpose: Disparities have been reported during the coronavirus disease (COVID-19) outbreak. Systemic lupus erythematosus (SLE) patients represent a unique group that is affected by clinical, treatment, demographic, and socioeconomic (SES) risk factors for severe COVID-19 disease. The Neighborhood Deprivation Index has been associated with non-communicable disease as well as communicable disease outcomes. We conducted this study to identify neighborhood SES factors influencing SLE COVID-19 outcomes.
Method(s): Patients with SLE and COVID-19 (confirmed by RT-PCR testing), were identified through a longitudinal survey of an established NYU lupus cohort, query of NYU Langone Health and Bellevue Hospitals systems and referrals from rheumatologists at those institutions. All patients were age 18 or older and met SLE classification criteria or carried a clinical diagnosis of SLE. Baseline characteristics along with zip code neighborhood data including COVID-19 case rates and neighborhood characteristics were obtained using the Hopkins COVID database and the American Community Surveys (ACS 2014-2018) respectively. A principal component analysis was performed to identify contributory neighborhood characteristics. Then a logistic regression analysis identified predictors of testing positive for COVID-19 and COVID-19 hospitalization.
Result(s): A total of 59 SLE patients (41+ and 18-) were tested for COVID-19 by RT-PCR. The patients were predominantly female, aged 46+/-16, and racially/ethnically diverse. Roughly 140 neighborhood data points were recorded and categorized as follows: population density, race and ethnicity, household type, household size, education level, employment type and status, income and poverty, transportation method, and insurance status. COVID-19 positive patients tended to live in neighborhoods with more single parent households, households with >4 residents, higher unemployment rate, higher high school dropout rate, more public transit use, and more employment in retail, construction, and personal care services. These variables were directly proportional to principal component 1 (PC1) and accounted for 88% of the variance in neighborhood characteristics. A logistic regression model identified that PC1 (OR= 1.3; 95% CI: 1.0-1.8) and taking immune suppressants (IS) (taking vs not taking OR= 2.1; 95% CI: 1.5 to 23.3) independently correlated with having a positive COVID-19 test when controlling for hydroxychloroquine (HCQ), glucocorticoids (GC), and previous lupus nephritis (LN). Only PC1 independently correlated with COVID-19 hospitalization (OR= 1.4; 95% CI: 1.1-1.9) upon controlling for taking IS, HCQ, GCs, and LN. PC1 associated with African American (AA) or Hispanic patient race/ethnicity (OR= 1.6, 95% CI: 1.2-2.2).
Conclusion(s): In addition to SLE disease, neighborhood characteristics and SES are important risk factors both for contracting COVID-19 and developing severe disease. Neighborhood deprivation may mediate the reported relationship between AA and Hispanic race/ethnicity and COVID-19. Given that a plurality of SLE patients are of AA and/or Hispanic backgrounds, care teams must formulate strategies to address socioeconomic stress in our patients

Background/Purpose: Tubulointerstitial damage in lupus nephritis (LN) is a strong predictor of progression to chronic kidney disease (CKD) and end stage renal disease (ESRD). While prior studies showed complement activation mediates glomerular injury, the role of complement in renal tubular damage has not been evaluated. The objective of this study is to investigate the association between complement activation as measured by tubular complement 9 (C9) deposition with interstitial fibrosis and tubular atrophy (IFTA) in LN.
Method(s): LN biopsies from July 2014 to July 2016 were evaluated. Chromogenic immunohistochemistry was performed on formalin-fixed, paraffin-embedded, 4-mum human renal biopsy sections using unconjugated, murine anti-human Complement C9 (Hycult Biotech, clone X197) as a marker of the membrane attack complex (MAC) activation. C3 glomerulopathy was used as a positive control and normal kidney served as a negative control. Tubular basement membrane C9 staining intensity was analyzed as absent (0) versus present (1 to 3) scored on a semi-quantitative scale by a renal pathologist. IFTA was categorized as 0-10%, 11-20%, and >20%. Clinical parameters were assessed at the time of biopsy and 6 months post biopsy.
Result(s): Renal biopsies from 30 LN patients were studied, of which 23 (77%) were proliferative LN. There were 24 (80%) women, mean age 33 (standard deviation) (12) years. Positive tubular C9 staining (C9+) was observed in 7 (23%) biopsies. At the time of renal biopsy, C9+ patients had significantly higher proteinuria, compared to C9- patients: median (interquartile range) 6.2g (3.3-13.1) vs. 2.4g (1.3-4.6), p< 0.01. The differences persisted at 6 months after induction therapy: 1.08g (1.0-8.3) in C9+ vs. 0.68g (0.2-2.1) in C9- patients, p=0.06. Tubular C9 deposition was associated with the finding of interstitial fibrosis on biopsy: 3 out of 7 (42.9%) had >20% interstitial fibrosis as compared to none in the C9- group, p=< 0.01. Higher proportion of C9+ patients had moderate NIH Chronicity index: 3 out of 7 (42.9%) vs 2 out of 23 (8.7%) in the C9- group, p=0.07. There was no significant difference in eGFR at renal biopsy between the two groups.
Conclusion(s): Tubular C9 deposition is associated with proteinuria, interstitial fibrosis and increased chronicity which are predictors of progression to ESRD. Complement activation may play an important role in tubulointerstitial damage in LN

Background/Purpose: Lupus nephritis (LN) is a major complication of systemic lupus erythematous (SLE) and affects ~60% of patients during the course of their disease, leading to significant morbidity and mortality. Previous studies examining the safety of percutaneous kidney biopsy to diagnose LN have found variable complication rates depending on disease type studied, ranging from 4-11% in autoimmune/SLE patients to 15-17% in safety studies of any kidney disease. The purpose of our study was to define the safety of obtaining additional tissue for research during clinically indicated renal biopsies in a SLE cohort.
Method(s): Patients were enrolled across 15 clinical US sites in the SLE Accelerating Medicines Partnership (AMP). Kidney biopsies were clinically indicated to evaluate proteinuria (urine protein creatinine ratio [uPCR] > 0.5). Patients with a history of renal transplant, use of rituximab within 6 months of biopsy, and current pregnancy were excluded. Ultrasound/CT-guided kidney biopsies were performed by interventional radiologists/nephrologists generally using an 18-gauge needle although technique, number of routine passes and core lengths varied. An additional core taken solely for research purposes, or a piece of core with sufficient glomeruli remaining from the routine passes and not required for clinical diagnosis, was collected. All adverse events (AEs) occurring within 30 days of biopsy were reported, including duration, severity, type, and resolution.
Result(s): 482 patients underwent a renal biopsy between 2014 and 2020. All patients met criteria for SLE (ACR or SLICC) and the majority were female (85%). Pathologic assessment of clinical biopsies revealed ISN/RPS Class I-VI for most biopsies, although 45 biopsies (9%) yielded a non-LN diagnosis (Table 1). Overall, 37 patients (8%) experienced an AE with several more than one, with a total of 41 AEs reported. Of these AEs, 8 (20%) were considered by the site investigator to be unrelated or unlikely to be related (included pain, shortness of breath, cardiac arrest, fall, and hemoglobin decrease due to sepsis) and 33 (80%) were deemed possibly, probably, or definitely related to the study procedure. Of these events, 9/33 (28%) were mild, 10 (30%) were moderate, and 12 (36%) were deemed severe. In 18 patients (4%) the AEs were considered serious as defined by inpatient or prolonged hospitalization, significant incapacity, or requiring intervention to prevent permanent impairment. The most common related AEs were bleed-related complications, including hematoma, hemorrhage, and hemoglobin decrease (N= 29). Of these, 18 required hospitalization, with 4 of these patients receiving a blood transfusion. All 29 bleed-related complications resolved. The length of the research biopsy did not associate with an AE.
Conclusion(s): Procurement of an additional kidney biopsy core for research purposes in SLE patients undergoing a clinically-indicated kidney biopsy did not result in an increase in adverse events compared to the adverse event rate in prior studies of the safety of percutaneous kidney biopsy. Accordingly, inclusion of a research core should be considered feasible for future studies to advance discovery of new therapeutic targets and prognostic indicators in LN

Background/Purpose: Current management of lupus nephritis (LN) is guided by histopathological features on kidney biopsy and measurement of proteinuria. Urine proteomics is a non-invasive source of novel biomarkers which may better reflect the complex dynamic immunobiology of LN in real time. Two composite measures include CKD273, which can predict the risk of progression of chronic kidney disease in the general population, and LN120, which was designed to diagnose LN. Both are multidimensional urine proteomic classifiers consisting of 273 or 120 peptides, respectively, with major components including collagen fragments, abundant blood-derived proteins, and proteins involved in inflammation. We investigated the ability of these classifiers to predict traditional biopsy features and disease response in LN.
Method(s): A total of 31 adults with biopsy-proven LN were included in this study. All participants met the SLICC and 2019 EULAR/ACR Classification Criteria for SLE based on a spot urine protein-to-creatinine ratio of >0.5 and class III, IV, and/or V LN on renal biopsy. Urine samples were collected at week 0 (at the time of renal biopsy) and week 12 and then subjected to peptidome analysis using a capillary electrophoresis-mass spectrometry (CE-MS) platform. This peptidome data was used to calculate CKD273 and LN120 classifiers at each time point. LN response status was determined at week 52 based on proteinuria, creatinine, and prednisone dosage (no more than 10 mg daily). Spearman's rank correlation and t-tests were used to compare proteomic classifiers with renal biopsy characteristics and response.
Result(s): At week 0, both CKD273 and LN120, but not proteinuria, exhibited a moderate to strong correlation with histological activity index on renal biopsy (Figure 1; rho = 0.65 with p = 0.00024 for CKD273; rho = 0.47 with p = 0.013 for LN120). CKD273 also correlated with chronicity index (rho = 0.54, p = 0.0037). Neither classifier significantly correlated with lupus nephritis ISN class. With respect to response, CKD273 and LN120 were not significantly different between groups at week 0. However, a reduction in LN120 was observed in 100% of complete responders, 60% of partial responders, and 50% of non-responders at week 12 (Figure 2). The magnitude of this change in LN120 in complete responders versus non-responders did not reach statistical significance (p = 0.13), though this is potentially because of the small number of responders with CE-MS data available at both time points (n = 4). CKD273 did not significantly change with time in any response group (Figure 3).
Conclusion(s): This work provides proof of concept that urine proteomic classifiers can noninvasively predict histological activity and chronicity in LN. Complete responders, but not partial responders or non-responders, exhibited an impressive numerical decrease in LN120 by week 12, suggesting that proteomic scores may track with and predict a durable treatment response. Larger studies are needed to validate these findings

Background/Purpose: Lupus nephritis continues to be the complication with the highest standardized mortality ratio in Systemic Lupus Erythematosus (SLE), and a late diagnosis associates with worse outcomes. Clinicians traditionally rely on proteinuria to drive decisions regarding renal biopsy and subsequent management. Since threshold levels for such determinations are variable but critically important, this study leveraged the well-phenotyped multi-center multi- racial Accelerating Medicines Partnership (AMP) lupus nephritis cohort, to address whether urine protein to creatinine ratios (UPCR) between.5 and 1 differ from higher ratios with regard to clinical, serologic and histologic variables.
Method(s): 239 patients fulfilling ACR or SLICC criteria for SLE with a random or 24 hr uPCR > or =.5 and histologic biopsy Class III, IV, V, or mixed were consecutively enrolled in AMP at the time of renal biopsy and demographics, clinical history, medications, disease activity as assessed by the hybrid SELENA-SLEDAI were recorded. Patients with biopsy Classes I, II and VI were ineligible. Patients were followed at 3, 12, 26 and 52 weeks.
Result(s): At baseline, 38 patients had a UPCR < 1 (A), 113 had a UPCR 1-3 (B), and 88 had a UPCR > 3 (C). There were 14 additional patients with UPCR < 1, and 11 patients with UPCR > 1 who had biopsy class I or II. In group A, there were significantly more male patients (44% A; 23% B; 26% C, p=0.012) with no differences in age, race or ethnicity. Neither the SLEDAI nor serologic parameters (anti-dsDNA, C3, or C4) distinguished among the groups. Those in group C had a significantly increased creatinine and decreased hemoglobin and albumin compared to the other two groups (Table 1). Patients in group A trended toward having an increased frequency of proliferative histology (Table 2). This trend was not observed when considering patients for whom this was their first biopsy, but was significant for repeat biopsy patients (56% A; 41% B; 24% C, p=0.03). The activity index was independent of UPCR regardless of biopsy number. However, those in group C had a significantly higher chronicity index than those with lower UPCR. This correlation was shown for patients with a repeat biopsy (r=0.2299, p=0.003) but not first biopsy patients (r=0.0891, p=0.45). Although medications did not differ at baseline among the groups, at 12 weeks, for each group significantly more patients were taking Mycophenolate Mofetil than at the time of biopsy (Table 3).
Conclusion(s): A significant proportion of both first and recurrent biopsies in patients with a UPCR < 1 have proliferative histology and accompanying activity scores similar to that of patients with nephrotic range proteinuria. These results support renal biopsy at thresholds lower than a UPCR of 1 since histologic findings can inform therapeutic decisions

Background/Purpose: Treatment of lupus nephritis relies on renal histopathological features. However, renal biopsies do not capture patient-specific active biological pathways. Urine proteomic biomarkers could revolutionize the diagnosis and management of lupus nephritis by predicting active intrarenal biological pathways and can be noninvasively monitored over time.
Method(s): One thousand proteins were quantified (RayBiotech) in a total of 112 longitudinal urine samples from 30 SLE patients with active lupus nephritis and 7 healthy controls (HC). The proteins and molecular pathways detected in the urine proteome at the time of biopsy were then analyzed with respect to lupus nephritis class, response to treatment after 1 year, histopathological features (activity and chronicity indeces), and trajectory over time (baseline and week 12, 26, and 52). The intrarenal expression of candidate biomarkers was evaluated using single cell transcriptomics of renal biopsies from patients with active lupus nephritis.
Result(s): There were 237 proteins (FDR < 10%) enriched in the urine of patients with lupus nephritis reflecting several molecular pathways involving chemotaxis, extracellular matrix remodeling, and activation of neutrophils and platelets. Hierarchical clustering using urine proteomics segregated SLE patients into 2 groups, with 80% of complete responders clustering together. This finding could not be similarly reproduced using standard features including baseline proteinuria, creatinine, histologic activity or chronicity scores, or class, indicating unique informative features of urine proteomics (Fig. 1). Patients with proliferative lupus nephritis (class III or IV) had stronger activation of chemotaxis pathways. IL-16 was the urinary protein most significantly increased in proliferative disease compared to membranous (FC 6, p=0.002) (Fig. 2A). Assessment of urine proteins that correlated with histologic activity kidney highlighted IL-16 as the single most strongly correlated protein with histologic activity (r=0.69, p=9.5.10-5; Fig. 2B). IL-16 concentration was independent of the amount of proteinuria and progressively diminished over time in patients who were responding to immunosuppression (Fig. 2C). Single cell RNA sequencing revealed significant intrarenal expression of IL16 by all infiltrating immune cells and highlighted IL16 as the second most expressed cytokine in lupus nephritis kidneys out of a compendium of 236 cytokines (Fig. 3A-B).
Conclusion(s): Urine proteomics can noninvasively identify active and biologically relevant pathways in lupus nephritis. Integrated urine proteomics and renal single cell transcriptomics revealed that IL-16, a CD4 ligand with chemotactic and proinflammatory functions, was one of the most expressed cytokine in lupus nephritis. As a urine proteomic biomarker, IL-16 may predict renal histological activity and could be monitored over time to assess response to immunosuppression. Urinary IL-16 is independent of proteinuria thus potentially providing actionable clinical information that is not captured by currently used biomarkers. Further studies are ongoing to validate these findings