Faculty Bibliography

BACKGROUND:Interstitial fibrosis in lupus nephritis (LN) is often infiltrated by immune cells but typically regarded as non-specific 'scar reaction'. This study aimed to investigate the relationship between inflammatory fibrosis and kidney disease progression in LN. METHODS:Interstitial fibrosis and tubular atrophy (IFTA) were scored in 124 LN kidney biopsies. Inflammation in areas of IFTA (i-IFTA) was graded 0-3 according to the Banff Classification of Allograft Pathology. Significant glomerular filtration rate (GFR) loss was defined as a decline of >15 mL/min at 3 years from biopsy. Immune cell phenotype was defined by serial immunohistochemistry (13-plex). RESULTS:IFTA was observed in 88/124 (71%) biopsies, and i-IFTA was identified in 76/88 (86%) cases. The distribution of i-IFTA grades was heterogeneous across all IFTA grades. In patients with moderate-to-severe IFTA (>25%), the degree of i-IFTA was associated with a higher risk of significant GFR loss: 0/1 (0%), 0/3 (%), 3/4 (75%) and 7/9 (78%) for i-IFTA grades 0, 1, 2 and 3, respectively (p=0.015). Multiplexed histology revealed that i-IFTA was mostly composed of CD163+ macrophages and CD4 T cells, followed by CD8 T cells and granulocytes. CONCLUSION/CONCLUSIONS:I-IFTA is frequently observed in LN and is dominated by macrophages and T cells. For patients with baseline IFTA >25%, the degree of i-IFTA emerged as a predictor of GFR loss. These data support the routine scoring of i-IFTA in LN due to its prognostic implications and nominate i-IFTA as a potential therapeutic target.

OBJECTIVES/OBJECTIVE:There is a lack of high-quality data to inform risk-stratified long-term thrombosis prevention strategies in patients with persistently positive antiphospholipid antibodies (aPL). We aimed to determine independent clinical and biologic predictors of thrombosis among persistently aPL-positive patients. METHODS:Patients positive for aPL according to the Revised Sapporo Classification Criteria are eligible for inclusion in the Antiphospholipid Syndrome Alliance for Clinical Trials and International Networking (APS ACTION) Registry. Registrants with at least 1 year of follow-up were included in this study. We fit Cox proportional hazards models to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for independent predictors of thrombosis. RESULTS:In unadjusted analyses, based on 1067 patients with a mean follow-up of 4.43 years (4,727 person-years), history of thrombosis, hematologic disease (autoimmune haemolytic anaemia and/or thrombocytopenia), microvascular disease, obesity, renal disease, sedentary lifestyle, baseline anticoagulant use, and family history of early cardiovascular disease occurred more frequently (P < .05) among patients with new thrombosis (n = 93) than among those without new thrombosis (n = 974). After adjustment, independent predictors of new thrombosis were history of thrombosis (HR 2.34, 95% CI 1.14 to 4.81, P = .02) and hematologic disease (HR 1.95, 95% CI 1.19 to 3.18, P = .01); there was a trend for history of microvascular disease (P = .06) and obesity (P = .08). CONCLUSIONS:In this prospective analysis, history of thrombosis and hematologic disease each conferred an approximately twofold increased risk of new thrombosis in persistently aPL-positive patients. These findings can guide future clinical trial designs and inform patient management decisions.

Systemic lupus erythematosus (SLE) is a complex autoimmune disease with an increased risk of vascular dysfunction and cardiovascular disease. We validate our previously developed Systemic Lupus Erythematosus Activity Platelet-Gene Expression Signature (SLAP-GES) score and investigate its relationship with platelet activity and vascular health. SLAP-GES was associated with the SLE Disease Activity Index (Padj < 0.001) and consistent over time (r = 0.76; P = 9 × 10^-5). Moreover, SLAP-GES was associated increased platelet aggregation in response to submaximal epinephrine (P = 0.084), leukocyte platelet aggregates (P = 0.014), and neutrophil platelet aggregates (P = 0.043). SLAP-GES was also associated with impaired glycocalyx (P = 0.011) and brachial artery flow-mediated dilation (P = 0.045). Altogether, SLAP-GES is associated with SLE disease activity, platelet activity, and impaired vascular health.

Monocytes and macrophages in patients with lupus nephritis exhibit altered behavior compared with healthy kidneys. How to optimally use mouse models to develop treatments targeting these cells is poorly understood. This study compared intrarenal myeloid cells in four mouse models and 155 lupus nephritis patients using single-cell profiling, spatial transcriptomics, and functional studies. Across mouse models, monocyte and macrophage subsets consistently expanded or contracted in disease. A subset of murine classical monocytes expanded in disease; these cells expressed Cd9, Spp1, Ctsd, Cd63, Apoe, and Trem2, genes associated with tissue injury in other organs that play roles in inflammation, lipid metabolism, and tissue repair. Resident macrophages expressed similar genes in clinical disease. In humans, we identified analogous disease-associated monocytes and macrophages that were associated with kidney histological subtypes and disease progression, sharing gene expression and localizing to similar kidney microenvironments as in mice. This cross-species analysis supports the use of mouse functional studies for understanding human lupus nephritis.

OBJECTIVE:Lupus nephritis (LN) management remains challenging, and novel noninvasive biomarkers are needed. This study quantified serum soluble mediators in the Accelerating Medicines Partnership (AMP) LN cohort to identify biomarkers of histological features and treatment response. METHODS:SLE patients (n=268) undergoing clinically indicated kidney biopsies (urine protein/creatinine ratio [UPCR] > 0.5) were recruited through the AMP RA/SLE network. Serum was collected at biopsy and 3-, 6-, and 12-months post-biopsy, alongside samples from 22 healthy controls. Concentrations of 66 immune mediators were quantified using xMAP multiplex assays, and TNF-α converting enzyme (TACE) measured by ELISA. Seven mediators with >95% values below detection limits were excluded from analyses. Bootstrapped LASSO regression identified proliferative LN (class III/IV+V) predictors from baseline mediators. Associations with 12-month treatment response (complete/partial vs. no response) were tested using 3-month changes in LASSO-selected mediators and UPCR via logistic regression. Molecular clustering of mediator profiles was performed to identify LN subgroups. RESULTS:Proliferative LN patients (class [III or IV] + V; n=160) displayed a distinct mediator profile compared to non-proliferative LN (class I/II/V; n=96). LASSO regression identified 20 mediators predictive of proliferative LN (AUC, 0.82; 95% CI, 0.81-0.91), including elevated syndecan-1, TNFRI, TNFRII, and VCAM-1, as well as decreased CCL3/MIP-1α, CD40L, and IL-5 levels. Among proliferative LN patients, 3-month reductions in syndecan-1 and VCAM-1, mediators associated with intrarenal LN activity and/or chronicity, predicted 12-month treatment response. A model incorporating these reductions and a decline in UPCR predicted treatment response in proliferative LN (0.90; 95% CI, 0.82-0.98). Molecular clustering revealed 4 distinct LN subgroups with unique soluble mediator signatures and clinical features, not captured by histology alone. CONCLUSION/CONCLUSIONS:Serum soluble mediators, particularly syndecan-1 and VCAM-1, reflect LN histological activity and early decreases predict treatment response, supporting their potential utility as noninvasive longitudinal biomarkers. The substantial heterogeneity within LN highlights the potential for biomarker-guided reclassification to advance precision medicine approaches.

OBJECTIVES/OBJECTIVE:There is a limited number of studies comparing paediatric to adult antiphospholipid syndrome (APS) patients. Our objective was to analyse the characteristics of patients presenting with antiphospholipid antibody (aPL)-related clinical manifestations during childhood versus adulthood. METHODS:We retrieved baseline characteristics from an international registry of persistently aPL-positive adult patients. Clinical events were grouped as vascular and non-vascular. We compared the frequency of and the timeline between vascular and non-vascular events for different age groups at the time of their first aPL-related manifestations: a) paediatric- (0-17 years) versus adult-onset (18-75 years); and b) based on narrower age intervals. Secondly, we analysed the timeline between the first aPL-related clinical event and first aPL positivity. RESULTS:Of 787 patients, 447 (57%) had only vascular events, 108 (14%) only non-vascular events, and 232 (29%) both. Compared to adult-onset patients (n=742), paediatric-onset patients (n=45) presented more commonly with a non-vascular event (49% vs. 19%, p=0.0001). The percentage of patients presenting with a non-vascular event mostly decreased with each increasing age group. Timeline analysis demonstrated 317 (40%) patients had a positive aPL test within the same calendar year (c-y) of the first clinical event, 207 (26%) within 1 to 3 c-y, and 263 (33%) more than 3 c-y. CONCLUSIONS:Our analysis of an international registry for persistently aPL-positive patients demonstrates that patients with paediatric-onset aPL-related manifestations more commonly present with non-vascular events. These results highlight the importance of understanding the clinical differences between paediatric and adult APS patients, which have diagnostic, therapeutic, and research implications.

OBJECTIVE:The objective was to determine the mortality rate as well as the causes and predictors of mortality in antiphospholipid antibody (aPL)-positive patients with/without APS classification. METHODS:The inclusion criteria for the multicenter international APS ACTION registry are positive aPL according to the Revised Sapporo Classification Criteria tested within one year prior to enrollment. Patients are followed every 12 ± 3 months with clinical data and blood collection. For this prospective analysis, firstly we analyzed the causes of death for patients reported as "deceased". Secondly, we analyzed risk factors for mortality using adjusted Cox proportional hazards model, and calculated the survival probability by Kaplan-Meier model based on different age groups. RESULTS:Of 967 patients, 43 (5%) were deceased after a median follow-up of 5.3 years. Based on the univariate analysis, deceased patients, compared to non-deceased, were more likely to be older and have a history of arterial thrombosis, catastrophic APS (CAPS), concomitant systemic autoimmune diseases (SAIDx), and baseline cardiovascular disease (CVD) risk factors. Based on the cox proportional hazards model adjusted for age and for each of the strongest predictors of mortality, arterial thrombosis (HR 2.94, 95% CI 1.50-5.76), concomitant SAIDx (HR 2.97, 95% 1.56-5.63), and baseline any CVD risk factor (HR 2.43, 95% CI 1.05-5.71) were significantly associated with mortality. CONCLUSION/CONCLUSIONS:In our cohort of persistently aPL-positive patients, the mortality rate was 5% after a median follow-up of five years, highest for patients over 60 years-old at registry entry. History of arterial thrombosis, concomitant SAIDx, and baseline any CVD risk factor independently predicted future mortality.

OBJECTIVES/OBJECTIVE:Glucagon-like peptide-1 receptor agonists (GLP1-RA) are an emerging class of medications with demonstrated promise in improving cardiometabolic outcomes. Whether these drugs may be useful in mitigating the cardiac risk associated with SLE remains unknown, and a recent case of drug induced lupus secondary to GLP1-RA use calls the safety of GLP1-RAs in SLE patients into question. Accordingly, this retrospective analysis was initiated to evaluate outcomes of GLP1-RAs in SLE. METHODS:All patients in the NYU Lupus Cohort who had used a GLP1-RA were eligible for inclusion. Patient characteristics were assessed at baseline (most recent rheumatology visit prior to starting GLP1-RA), 1-4 months, and 6-10 months after GLP1-RA initiation. RESULTS:Of the 1211 patients in the cohort, only 24 had received a GLP1-RA. Six were excluded due to insufficient documentation regarding duration of medication use. Of the remaining 18 (median age 50), 17 (94%) were female and 9 (50%) were white. There was one mild-to-moderate flare at 6-10 months, but no patients accumulated new SLE criteria during the follow up period. Compared with baseline, median BMI was reduced by 3% at 1-4 months (p= 0.002) and 13% at 6-10 months (p= 0.001). Nine (50%) patients were initially denied insurance coverage for a GLP1-RA. CONCLUSION/CONCLUSIONS:While limited by a small sample size, this descriptive study showed that GLP1-RAs did not trigger flares above expected background rates and were associated with significantly decreased BMI. Future studies exploring the potential benefits of GLP1-RAs in patients with SLE are warranted.

OBJECTIVES/OBJECTIVE:This study focused on the prevalence and impact of antinuclear antibodies (ANA) in antiphospholipid antibody (aPL)-positive patients without concomitant systemic autoimmune rheumatic diseases (SARDs). METHODS:Data from aPL-positive patients with or without Revised Sapporo APS classification criteria were retrieved from the APS ACTION Registry. Patients with concomitant SARDs were excluded. RESULTS:430 aPL-positive patients were included in the analysis, 56% ANA-positive and 44% negative. ANA positivity was significantly associated with history of hematologic manifestations (persistent autoimmune hemolytic anaemia, thrombocytopenia, leukopenia and/or lymphopenia) (16% of ANA-positive vs 7% of ANA-negative, p= 0.006). Triple aPL-positivity was more frequent in the ANA-positive subgroup (p= 0.02), along with low baseline C3 and C4 levels (p= 0.05 and p= 0.009, respectively), and higher frequency for extractable nuclear antigens (ENA). Among aPL-positive patients with no APS classification, ANA-positive patients showed a higher rate of arthritis (p= 0.006). Among female patients who have experienced at least one pregnancy, 113 were ANA-positive and 96 were ANA-negative; ANA-negative patients had a higher number of pregnancies (p= 0.018), and number of live births (p= 0.014). A wider proportion of ANA-positive patients were treated with hydroxychloroquine (HCQ) (p< 0.001). CONCLUSION/CONCLUSIONS:When we analysed aPL-positive patients with no other SARDs, ANA status was not associated with thrombosis or pregnancy morbidity. Interestingly, ANA-positive patients showed higher rates of systemic autoimmune features, including hematologic manifestations, multiple aPL positivity, lower complement levels, ENA positivity, and joint involvement, and were more often treated with HCQ. Finally, aPL-positive subjects who were ANA-negative had a higher rate of pregnancies and live births.