CD38 in SLE CD4 T cells promotes Ca2+ flux and suppresses interleukin-2 production by enhancing the expression of GM2 on the surface membrane.

CD38 has emerged as a potential therapeutic target for patients with systemic lupus erythematosus (SLE) but it is not known whether CD38 alters CD4+ T cell function. Using primary human T cells and CD38-sufficient and CD38-deficient Jurkat T cells, we demonstrate that CD38 shifts the T cell lipid profile of gangliosides from GM3 to GM2 by upregulating B4GALNT1 in a Sirtuin 1-dependent manner. Enhanced expression of GM2 causes ER stress by enhancing Ca2+ flux through the PLCγ1-IP3 pathway. Interestingly, correction of the calcium overload by an IP3 receptor inhibitor, but not by a store-operated calcium entry (SOCE) inhibitor, improves IL-2 production by CD4+ T cells in SLE. This study demonstrates that CD38 affects calcium homeostasis in CD4+ T cells by controlling cell membrane lipid composition that results in suppressed IL-2 production. CD38 inhibition with biologics or small drugs should be expected to benefit patients with SLE.

Expanded CD8+CD38+ T Cell Population in Patients With Systemic Lupus Erythematosus Is Linked to Increased Infection Rates: A Prospective Study.

OBJECTIVE: One of the leading causes of morbidity and mortality among patients with systemic lupus erythematosus (SLE) is infections. The expression of the ectonucleotidase CD38 on the surface of CD8+ T cells has been linked to compromised cytotoxic function. The aim of this prospective study was to assess whether the presence of CD8+CD38+ in the peripheral blood of patients with SLE can serve as a biomarker for infectious complications. METHODS: A cohort of 80 patients with SLE were recruited over 18 months. The rate of clinically significant infections and presence of CD8+CD38+ T cells in the peripheral blood were monitored at each clinic visit. The patients were classified into high CD38+ and low CD38+ CD8+ T cells using flow cytometry and a previously established cutoff rate of 28.4%. RESULTS: A total of 20 infections were registered over the study period. We observed that the patients with an expanded CD8+CD38+ T cell population in the peripheral blood had a higher rate of recurrent infections and a higher likelihood of infection compared with patients with a low CD8+CD38+ T cell population. The levels of CD38 in CD8+ T cells remained stable over time in the studied subjects. CONCLUSION: High levels of CD8+CD38+ T cells in the peripheral blood of patients with SLE identify a subgroup prone to infections for whom proper clinical measures should be applied.

New and emerging therapies for systemic lupus erythematosus.

Systemic Lupus Erythematosus (SLE) and lupus nephritis treatment is still based on non-specific immune suppression despite the first biological therapy for the disease having been approved more than a decade ago. Intense basic and translational research has uncovered a multitude of pathways that are actively being evaluated as treatment targets in SLE and lupus nephritis, with two new medications receiving FDA approval in the last 3 years. Herein we provide an overview of targeted therapies for SLE including medications targeting the B lymphocyte compartment, intracellular signaling, co-stimulation, and finally the interferons and other cytokines.

Journal Club: Anti-CD19 Chimeric Antigen Receptor T Cell Therapy for Refractory Systemic Lupus Erythematosus.

OBJECTIVE: Despite substantial advances in the treatment of systemic lupus erythematosus (SLE), some patients do not respond to the current state-of-the art therapies. This study assessed the tolerability and efficacy of CD19 chimeric antigen receptor (CAR) T cells in a small series of seriously ill and treatment-resistant patients with SLE. METHODS: Five patients with SLE (four female patients and one male patient) with a median age of 22 (range 18-24) years, a median disease duration of 4 (range 1-9) years, and active disease (median Systemic Lupus Erythematosus Disease Activity Index score of 16 [range 8-16]) refractory to several immunosuppressive drug treatments were enrolled in a compassionate-use CAR-T cell program. Autologous T cells from patients with SLE were transduced with a lentiviral anti-CD19 CAR vector, expanded, and reinfused at a dose of 1 × 106 CAR T cells per kilogram of body weight into the patients after lymphodepletion with fludarabine and cyclophosphamide. RESULTS: CAR T cells expanded in vivo and led to deep depletion of B cells, improvement of clinical symptoms, and normalization of laboratory parameters, including seroconversion of anti-double-stranded DNA antibodies. Remission of SLE according to definition of remission in SLE criteria was achieved in all five patients after 3 months, and the median Systemic Lupus Erythematosus Disease Activity Index score after 3 months was 0 (range 2). Drug-free remission was maintained during longer follow-up (median of 8 [range 12] months after CAR-T cell administration) and even after the reappearance of B cells, which was observed after a mean (±SD) of 110 ± 32 days after CAR-T cell treatment. Reappearing B cells were naive and showed non-class-switched B cell receptors. CAR-T cell treatment was well tolerated, with only mild cytokine release syndrome. CONCLUSION: These data suggest that CD19 CAR-T cell therapy was feasible, tolerable, and effective in this small case series of refractory SLE. Nevertheless, larger placebo-controlled trials are warranted.

Predictors of a weak antibody response to COVID-19 mRNA vaccine in systemic lupus erythematosus.

OBJECTIVES: To characterize the antibody response to COVID-19 mRNA vaccination in patients with Systemic Lupus Erythematosus (SLE) and identify predictors of poor response. METHODS: SLE patients who are followed at the Beth Israel Deaconess Medical Center Lupus Cohort (BID-LC) were enrolled. SARS-CoV-2 IgG Spike antibody was measured in patients who received two doses of either the BNT162b2 (Pfizer-BioNTech) or the mRNA-1273 (Moderna) COVID-19 vaccine (n = 62). We defined non-responders as patients with an IgG Spike antibody titer less than two-fold (< 2) the index value of the test and responders as patients with antibody levels greater or equal to two-fold (≥ 2). A web-based survey was used to collect information regarding immunosuppressive medication use and SLE flares after vaccination. RESULTS: In our cohort of lupus patients, 76% were vaccine responders. The use of two or more immunosuppressive drugs was associated with being a non-responder (Odds Ratio 5.26; 95% CI 1.23-22.34, p = 0.02). Both Belimumab use and higher Prednisone dose were associated with vaccine non-response (p = 0.04 and p = 0.04). The non-responder group had higher mean levels of serum IL-18 than the responder group (p = 0.04) as well as lower C3 levels (p = 0.01). Lupus flares and breakthrough infections were uncommon post-vaccination. CONCLUSIONS: Immunosuppressive medications have a negative impact on vaccine humoral response in SLE individuals. We observed a trend towards vaccine no-response in BNT162b2 recipients and a relationship between IL-18 and impaired antibody response that merits further investigation.

Prevalence and clinical significance of lymphadenopathy and its histological subtypes in patients with systemic lupus erythematosus: a retrospective cohort study.

The objective of this study was to evaluate the prevalence and the clinical significance of lymphadenopathy and its histological subtypes in patients with systemic lupus erythematosus. We conducted a retrospective cohort study of patients with SLE diagnosed using the 1997 ACR criteria, who were followed at our institution between 2008 and 2022. Patients were grouped based on the presence of SLE-attributed LAD and its histological phenotype, then compared in terms of demographic, clinical and laboratory characteristics. Of the 255 patients, 33.7% had SLE-attributed, 0.8% lymphoma-related and 0.4% tuberculosis-related LAD. Univariate analysis identified significant associations between the presence of LAD and fever (p < 0.0001), weight loss (p = 0.009), pericarditis (p = 0.004), myocarditis (p = 0.003), myositis (p = 0.034), leukopenia (p = 0.004), lymphopenia (p = 0.003), membranous nephritis (p = 0.004), anti-RNP (p = 0.001), anti-Smith (p = < 0.0001), and SSB antibodies (p = 0.038), and hypocomplementemia (C3:p = 0.019; C4:p < 0.0001). Logistic regression confirmed the associations of LAD with fever (OR = 3.277, 95% C.I 1.657-6.481), pericarditis (OR = 4.146, 95% C.I:1.577-10.899), membranous nephritis (OR = 3.586, 95% C.I:1.305-9.854), and leukopenia (OR = 2.611, 95%C.I:1.319-5.166), but not with weight loss, myocarditis, or myositis. Biopsy in a subset of patients (33.7% of total) revealed reactive/proliferative (62.1%) or necrotizing (37.9%) histological patterns. When we compared the histologic patterns, necrotizing LAD was associated with fever (p = 0.052), sicca (p = 0.018), and malar rash (p = 0.005). Most patients received corticosteroids, hydroxychloroquine, and/or DMARDs with relatively quick clinical improvement. In conclusion, LAD is a common SLE manifestation, associated with constitutional symptoms, myo-/pericarditis, myositis, cytopenia, and membranous nephritis. Despite relatively high prevalence of LAD in SLE, a biopsy may still be needed to rule out lymphoma.

Undifferentiated Connective Tissue Disease: Comprehensive Review.

PURPOSE OF REVIEW: Undifferentiated connective tissue disease (UCTD) is characterized by the presence of clinical symptoms of a systemic autoimmune disease in addition to laboratory evidence of autoimmunity with the patients not fulfilling any of the widely used classification criteria for classic autoimmune diseases. The presence of UCTD as a separate entity versus an early stage of such diseases as systemic lupus erythematosus (SLE) or scleroderma has long been debated. Given the uncertainty regarding this condition, we performed a systematic review on the topic. RECENT FINDINGS: UCTD can be subcategorized as evolving (eUCTD) or stable UCTD (sUCTD) based on its evolution towards a definable autoimmune syndrome. Analyzing the data from six UCTD cohorts published in the literature, we found that 28% of patients have an evolving course with the majority developing SLE or rheumatoid arthritis within 5-6 years of the UCTD diagnosis. From the remaining patients, 18% do achieve remission. Published treatment regimens were similar to other mild autoimmune diseases with low-dose prednisone, hydroxychloroquine, and NSAID. One-third of patients did need immune suppressive medications. Importantly, the reported outcomes were excellent with survival rates of more than 90% over 10 years. It has to be noted though that as data on patient related outcomes are not available to date, the exact impact of this condition on quality of life is unclear. UCTD is a mild autoimmune condition with generally good outcomes. There is still great uncertainty though regarding diagnosis and management. Going forward, consistent classification criteria are needed to advance UCTD research and eventually provide authoritative guidance on the management of the condition.

Estimating glucocorticoid-related morbidity in lupus nephritis using the glucocorticoid toxicity index.

OBJECTIVE: Lupus nephritis (LN) is often treated with high doses of glucocorticoids (GCs). The glucocorticoid toxicity index (GTI) was developed by expert consensus to quantify GC toxicity. To date, the GTI has not been shown to correlate with GC exposure in patients with LN. METHODS: We performed a retrospective cohort study of patients with biopsy-confirmed LN between 2006 and 2016. Cumulative GC exposure and GTI scores were determined via medical record review. Both the aggregate improvement score (GTI-AIS) and the cumulative worsening score (GTI-CWS) were calculated. We performed linear regression to determine the association between GC exposure and GTI scores at 1 year and 5 years following kidney biopsy. RESULTS: This study included 49 patients with a mean age of 33.3 (SD 9.5) years. Mean GC exposure was 23.0 mg prednisone-equivalents per day through year 1 and 9.9 mg prednisone-equivalents per day through year 5. At 5 years, higher GC exposure was associated with higher GTI-AIS (p < 0.001) and GTI-CWS (p = 0.002), and this association persisted in multivariate analysis adjusting for age, sex, race, induction medication, and nephritis class (p = 0.026 for AIS, p = 0.012 for CWS). At 1 year, GC exposure was not associated with GTI scores (p = 0.70 for AIS; p = 0.58 for CWS). CONCLUSION: In this cohort study, the GTI was associated with cumulative steroid exposure at 5 years after diagnosis. In patients with LN, the GTI may serve as a useful outcome measure in future LN trials evaluating the steroid sparing effect of novel therapies.

Role of Platelet-Bound C4d (PC4d) in Predicting Risk of Future Thrombotic Events in Systemic Lupus Erythematosus.

OBJECTIVE: Platelet-bound complement activation product C4d (PC4d) levels correlate with history of thrombosis in patients with systemic lupus erythematosus (SLE). The present study evaluated whether PC4d levels could assess risk of future thrombosis events. METHODS: PC4d level was measured by flow cytometry. Thromboses were confirmed by electronic medical record data review. RESULTS: The study included 418 patients. Nineteen events (13 arterial and 6 venous) occurred in 15 subjects in the 3 years post-PC4d level measurement. PC4d levels above the optimum cutoff of 13 mean fluorescence intensity (MFI) predicted future arterial thrombosis with a hazard ratio of 4.34 (95% confidence interval [95% CI] 1.03-18.3) (P = 0.046) and a diagnostic odds ratio (OR) of 4.30 (95% CI 1.19-15.54). Negative predictive value of PC4d level of ≤13 MFI for arterial thrombosis was 99% (95% CI 97-100%). Although a PC4d level of >13 MFI did not reach statistical significance for prediction of total thrombosis (arterial and venous) (diagnostics OR 2.50 [95% CI 0.88-7.06]; P = 0.08), it was associated with all thrombosis (n = 70 historic and future arterial and venous events in the 5 years pre- to 3 years post-PC4d level measurement) with an OR of 2.45 (95% CI 1.37-4.32; P = 0.0016). In addition, the negative predictive value of PC4d level of ≤13 MFI for all future thrombosis events was 97% (95% CI 95-99%). CONCLUSIONS: A PC4d level of >13 MFI predicted future arterial thrombosis and was associated with all thrombosis. Patients with SLE presenting with a PC4d level of ≤13 MFI had high probability of not experiencing arterial or any thrombosis in the 3 years afterwards. Taken together, these findings indicate that PC4d levels may help predict the risk of future thrombosis events in SLE.

Implementing a Virtual Flipped Classroom in a Rheumatology Fellowship Program.

OBJECTIVE: Active learning opportunities within graduate medical education may be underused. We aimed to assess whether active learning strategies increase after implementing a faculty development workshop and transitioning rheumatology fellowship didactics to a virtual flipped classroom. METHODS: We measured baseline faculty use of active learning strategies during lectures within the Introductory Rheumatology Curriculum by calculating an "active learning score" from a cognitive learning theory assessment tool. We held a faculty development workshop demonstrating active teaching strategies and encouraged using a flipped classroom for fellowship didactics. Because of the COVID-19 pandemic, the strategies were discussed in a virtual classroom setting where the intervention phase would occur. We compared active learning scores before and after the intervention for lectures within the Introductory Rheumatology Curriculum. The primary outcome was the change in active teaching scores preintervention versus postintervention. RESULTS: Active learning scores increased in 14 of the 16 lectures, with a mean score increase of 4.7 of 24 points (95% confidence interval 2.3-7.2). Paired t-test analyses comparing active learning scores preintervention and postintervention for each lecture confirmed that results were highly statistically significant (P < 0.001). Despite faculty hesitancy to teach within a virtual environment, faculty satisfaction remained high postintervention. CONCLUSION: A virtual flipped classroom increased the use of active learning strategies within the Introductory Rheumatology Curriculum. Faculty satisfaction remained high despite modest increases in time spent updating their presentations. Fellows and faculty reported a largely positive experience within the virtual classroom.