Endothelial mechanical stretch regulates the immunological synapse interface of renal endothelial cells in a sex-dependent manner.

Increased mechanical endothelial cell stretch contributes to the development of numerous cardiovascular and renal pathologies. Recent studies have shone a light on the importance of sex-dependent inflammation in the pathogenesis of renal disease states. The endothelium plays an intimate and critical role in the orchestration of immune cell activation through upregulation of adhesion molecules and secretion of cytokines and chemokines. While endothelial cells are not recognized as professional antigen-presenting cells, in response to cytokine stimulation, endothelial cells can express both major histocompatibility complex (MHC) I and MHC II. MHCs are essential to forming a part of the immunological synapse interface during antigen presentation to adaptive immune cells. Whether MHC I and II are increased under increased mechanical stretch is unknown. Due to hypertension being multifactorial, we hypothesized that increased mechanical endothelial stretch promotes the regulation of MHCs and key costimulatory proteins on mouse renal endothelial cells (MRECs) in a stretch-dependent manner. MRECs derived from both sexes underwent 5%, 10%, or 15% uniaxial cyclical stretch, and immunological synapse interface proteins were determined by immunofluorescence microscopy, immunoblot analysis, and RNA sequencing. We found that increased endothelial mechanical stretch conditions promoted downregulation of MHC I in male MRECs but upregulation in female MRECs. Moreover, MHC II was upregulated by mechanical stretch in both male and female MRECs, whereas CD86 and CD70 were regulated in a sex-dependent manner. By bulk RNA sequencing, we found that increased mechanical endothelial cell stretch promoted differential gene expression of key antigen processing and presentation genes in female MRECs, demonstrating that females have upregulation of key antigen presentation pathways. Taken together, our data demonstrate that mechanical endothelial stretch regulates endothelial activation and immunological synapse interface formation in renal endothelial cells in a sex-dependent manner.NEW & NOTEWORTHY Endothelial cells contribute to the development of renal inflammation and have the unique ability to express antigen presentation proteins. Whether increased endothelial mechanical stretch regulates immunological synapse interface proteins remains unknown. We found that antigen presentation proteins and costimulatory proteins on renal endothelial cells are modulated by mechanical stretch in a sex-dependent manner. Our data provide novel insights into the sex-dependent ability of renal endothelial cells to present antigens in response to endothelial mechanical stimuli.

Loss-of-function variants in SAT1 cause X-linked childhood-onset systemic lupus erythematosus.

OBJECTIVES: Families that contain multiple siblings affected with childhood onset of systemic lupus erythematosus (SLE) likely have strong genetic predispositions. We performed whole exome sequencing (WES) to identify familial rare risk variants and to assess their effects in lupus. METHODS: Sanger sequencing validated the two ultra-rare, predicted pathogenic risk variants discovered by WES and identified additional variants in 562 additional patients with SLE. Effects of a splice site variant and a frameshift variant were assessed using a Minigene assay and CRISPR/Cas9-mediated knock-in (KI) mice, respectively. RESULTS: The two familial ultra-rare, predicted loss-of-function (LOF) SAT1 variants exhibited X-linked recessive Mendelian inheritance in two unrelated African-American families. Each LOF variant was transmitted from the heterozygous unaffected mother to her two sons with childhood-onset SLE. The p.Asp40Tyr variant affected a splice donor site causing deleterious transcripts. The young hemizygous male and homozygous female Sat1 p.Glu92Leufs*6 KI mice spontaneously developed splenomegaly, enlarged glomeruli with leucocyte infiltration, proteinuria and elevated expression of type I interferon-inducible genes. SAT1 is highly expressed in neutrophils and encodes spermidine/spermine-N1-acetyltransferase 1 (SSAT1), a rate-limiting enzyme in polyamine catabolism. Young male KI mice exhibited neutrophil defects and decreased proportions of Foxp3 +CD4+ T-cell subsets. Circulating neutrophil counts and proportions of Foxp3 +CD4+ T cells correlated with decreased plasma levels of spermine in treatment-naive, incipient SLE patients. CONCLUSIONS: We identified two novel SAT1 LOF variants, showed the ability of the frameshift variant to confer murine lupus, highlighted the pathogenic role of dysregulated polyamine catabolism and identified SAT1 LOF variants as new monogenic causes for SLE.

Endothelial cells: potential novel regulators of renal inflammation.

Substantial evidence has supported the role of endothelial cell (EC) activation and dysfunction in the development of hypertension, chronic kidney disease (CKD), and lupus nephritis (LN). In both humans and experimental models of hypertension, CKD, and LN, ECs become activated and release potent mediators of inflammation including cytokines, chemokines, and reactive oxygen species that cause EC dysfunction, tissue damage, and fibrosis. Factors that activate the endothelium include inflammatory cytokines, mechanical stretch, and pathological shear stress. These signals can activate the endothelium to promote upregulation of adhesion molecules, such as intercellular adhesion molecule-1 and vascular cell adhesion molecule-1, which promote leukocyte adhesion and migration to the activated endothelium. More importantly, it is now recognized that some of these signals may in turn promote endothelial antigen presentation through major histocompatibility complex II. In this review, we will consider in-depth mechanisms of endothelial activation and the novel mechanism of endothelial antigen presentation. Moreover, we will discuss these proinflammatory events in renal pathologies and consider possible new therapeutic approaches to limit the untoward effects of endothelial inflammation in hypertension, CKD, and LN.

Developing and Validating Methods to Assemble Systemic Lupus Erythematosus Births in the Electronic Health Record.

OBJECTIVE: Electronic health records (EHRs) represent powerful tools to study rare diseases. Our objective was to develop and validate EHR algorithms to identify systemic lupus erythematosus (SLE) births across centers. METHODS: We developed algorithms in a training set using an EHR with over 3 million subjects and validated the algorithms at 2 other centers. Subjects at all 3 centers were selected using ≥1 code for SLE International Classification of Diseases, Ninth Revision (ICD-9) or SLE International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Clinical Modification (ICD-10-CM) and ≥1 ICD-9 or ICD-10-CM delivery code. A subject was a case if diagnosed with SLE by a rheumatologist and had a birth documented. We tested algorithms using SLE ICD-9 or ICD-10-CM codes, antimalarial use, a positive antinuclear antibody ≥1:160, and ever checked double-stranded DNA or complement, using both rule-based and machine learning methods. Positive predictive values (PPVs) and sensitivities were calculated. We assessed the impact of case definition, coding provider, and subject race on algorithm performance. RESULTS: Algorithms performed similarly across all 3 centers. Increasing the number of SLE codes, adding clinical data, and having a rheumatologist use the SLE code all increased the likelihood of identifying true SLE patients. All the algorithms had higher PPVs in African American versus White SLE births. Using machine learning methods, the total number of SLE codes and an SLE code from a rheumatologist were the most important variables in the model for SLE case status. CONCLUSION: We developed and validated algorithms that use multiple types of data to identify SLE births in the EHR. Algorithms performed better in African American mothers than in White mothers.

Prediction models of treatment response in lupus nephritis.

In order to develop prediction models of one-year treatment response in lupus nephritis, an approach using machine learning to combine traditional clinical data and novel urine biomarkers was undertaken. Contemporary lupus nephritis biomarkers were identified through an unbiased PubMed search. Thirteen novel urine proteins contributed to the top 50% of ranked biomarkers and were selected for measurement at the time of lupus nephritis flare. These novel markers along with traditional clinical data were incorporated into a variety of machine learning algorithms to develop prediction models of one-year proteinuria and estimated glomerular filtration rate (eGFR). Models were trained on 246 individuals from four different sub-cohorts and validated on an independent cohort of 30 patients with lupus nephritis. Seven models were considered for each outcome. Three-quarters of these models demonstrated good predictive value with areas under the receiver operating characteristic curve over 0.7. Overall, prediction performance was the best for models of eGFR response to treatment. Furthermore, the best performing models contained both traditional clinical data and novel urine biomarkers, including cytokines, chemokines, and markers of kidney damage. Thus, our study provides further evidence that a machine learning approach can predict lupus nephritis outcomes at one year using a set of traditional and novel biomarkers. However, further validation of the utility of machine learning as a clinical decision aid to improve outcomes will be necessary before it can be routinely used in clinical practice to guide therapy.

Up-Regulated Interleukin-10 Induced by E2F Transcription Factor 2-MicroRNA-17-5p Circuitry in Extrafollicular Effector B Cells Contributes to Autoantibody Production in Systemic Lupus Erythematosus.

OBJECTIVE: Elevated interleukin-10 (IL-10) levels in patients with systemic lupus erythematosus (SLE) have B cell-promoting effects, contributing to autoantibody production and tissue damage. We aimed to characterize up-regulated IL-10+ B cell subsets and dysregulated IL10 expression in SLE B cells for new therapeutic options. METHODS: Proportions of Th10 and IL-10+ B cell subsets in peripheral blood mononuclear cells (PBMCs) were assessed using flow cytometry. The IL10 3'-untranslated region (3'-UTR) dual-luciferase vector was constructed and cotransfected with small interfering RNA (siRNA), microRNA (miRNA) mimics, or miRNA inhibitors into Raji cells. Transcript levels were quantified using TaqMan assays. RESULTS: Culture conditions that induced IL-10+ Breg cells in healthy controls resulted in expansion of IL-10+ double-negative 2 (DN2; IgD-CD27-CD21-CD11c+) B cells in SLE PBMCs. Proportions of IL-10+ DN2, but not those of IL-10- DN2, correlated with disease activity and levels of antibodies to double-stranded DNA (dsDNA) (r = 0.60, P = 0.03 for cohort 1; r = 0.38, P = 0.03 for cohort 2), and were associated with high levels or seropositivity of anti-Sm (P = 0.03 for cohort 1; P = 0.01 for cohort 2) and IgG anticardiolipin (P < 0.01 for cohort 1; P = 0.02 for cohort 2) in SLE patients from 2 cohorts, of mainly African American subjects (cohort 1) and of Asian subjects (cohort 2). Proportions of Th10 (CD45RA-CXCR5-CXCR3+PD-1high CD4+) cells correlated with IL-10+ DN2 frequencies (r = 0.60, P < 0.01 for cohort 2), antinuclear antibody titers (r = 0.52, P = 0.01 for cohort 2), and proteinuria levels (r = 0.72, P < 0.01 for cohort 2) in SLE patients. Screening of predicted IL10 3'-UTR-targeting miRNAs in SLE B cells identified miRNA-17-5p (miR-17-5p) and miR-20a-5p, with their levels inversely correlated with IL10 (r = -0.47, P < 0.01 for miR-17-5p; r = -0.37, P = 0.03 for miR-20-5p) and transcription factor E2F2 (r = -0.48, P = 0.04 for miR-17-5p; r = -0.45, P = 0.05 for miR-20-5p). In Raji cells, knockdown of E2F2 expression resulted in increased levels of miR-17-5p and miR-20a-5p and decreased IL10 messenger RNA (mRNA) and protein levels, and overexpression and inhibition of miR-17-5p down-regulated and up-regulated, respectively, IL10 mRNA levels, suggesting regulation of IL10 expression by an E2F2-miR-17-5p loop. CONCLUSION: IL-10 promotes extrafollicular autoimmune responses in patients with active SLE, which might be dampened by targeting the E2F2-miR-17-5p circuitry.

The Effect of Travel Burden on Depression and Anxiety in African American Women Living with Systemic Lupus.

The United States has a deficit of rheumatology specialists. This leads to an increased burden in accessing care for patients requiring specialized care. Given that most rheumatologists are located in urban centers at large hospitals, many lupus patients must travel long distances for routine appointments. The present work aims to determine whether travel burden is associated with increased levels of depression and anxiety among these patients. Data for this study were collected from baseline visits of patients participating in a lupus study at MUSC. A travel/economic burden survey was assessed as well as the 8-item Patient Health Questionnaire (PHQ-8) and the 7-item Generalized Anxiety Disorder (GAD-7) survey as measures of depression and anxiety, respectively. Linear regression models were used to assess the relationship between travel burden and depression and anxiety. Frequency of healthcare visits was significantly associated with increased depression (ß = 1.3, p = 0.02). Significant relationships were identified between anxiety and requiring time off from work for healthcare appointments (ß = 4, p = 0.02), and anxiety and perceived difficulty in traveling to primary care providers (ß = 3.1, p = 0.04). Results from this study provide evidence that travel burden can have an effect on lupus patients' anxiety and depression levels.

Support Methodologies for African American Women With Lupus - Comparing Three Methods' Effects on Patient Activation and Coping.

Introduction: Systemic lupus erythematosus (SLE) is a chronic inflammatory disease in which the immune system attacks healthy tissues. While pharmaceutical therapies are an important part of disease management, behavioral interventions have been implemented to increase patients' disease self-management skills, provide social support, and encourage patients to take a more active role in their care. Methods: Three interventions are considered in this study; peer-to-peer methodology, patient support group, and a patient navigator program that were implemented among largely African American women with SLE at the Medical University of South Carolina (MUSC). Outcomes of interest were patient activation and lupus self-efficacy. We used a Least Squares Means model to analyze change in total patient activation and lupus self-efficacy independently in each cohort. We adjusted for demographic variables of age, education, income, employment, and insurance. Results: In both unadjusted and adjusted models for patient activation, there were no statistically significant differences among the three intervention methodologies when comparing changes from baseline to post intervention. Differences in total coping score from baseline to post intervention in the patient navigator group (-101.23, p-value 0.04) and differences in scores comparing the patient navigator with the support group were statistically significant (116.96, p-value 0.038). However, only the difference in total coping from baseline to post intervention for the patient navigator program remained statistically significant (-98.78, p-value 0.04) in the adjusted model. Conclusion: Tailored interventions are a critical pathway toward improving disease self-management among SLE patients. Interventions should consider including patient navigation because this method was shown to be superior in improving self-efficacy (coping scores).

Development of a lupus nephritis suboptimal response prediction tool using renal histopathological and clinical laboratory variables at the time of diagnosis.

OBJECTIVE: Lupus nephritis (LN) is an immune complex-mediated glomerular and tubulointerstitial disease in patients with SLE. Prediction of outcomes at the onset of LN diagnosis can guide decisions regarding intensity of monitoring and therapy for treatment success. Currently, no machine learning model of outcomes exists. Several outcomes modelling works have used univariate or linear modelling but were limited by the disease heterogeneity. We hypothesised that a combination of renal pathology results and routine clinical laboratory data could be used to develop and to cross-validate a clinically meaningful machine learning early decision support tool that predicts LN outcomes at approximately 1 year. METHODS: To address this hypothesis, patients with LN from a prospective longitudinal registry at the Medical University of South Carolina enrolled between 2003 and 2017 were identified if they had renal biopsies with International Society of Nephrology/Renal Pathology Society pathological classification. Clinical laboratory values at the time of diagnosis and outcome variables at approximately 1 year were recorded. Machine learning models were developed and cross-validated to predict suboptimal response. RESULTS: Five machine learning models predicted suboptimal response status in 10 times cross-validation with receiver operating characteristics area under the curve values >0.78. The most predictive variables were interstitial inflammation, interstitial fibrosis, activity score and chronicity score from renal pathology and urine protein-to-creatinine ratio, white blood cell count and haemoglobin from the clinical laboratories. A web-based tool was created for clinicians to enter these baseline clinical laboratory and histopathology variables to produce a probability score of suboptimal response. CONCLUSION: Given the heterogeneity of disease presentation in LN, it is important that risk prediction models incorporate several data elements. This report provides for the first time a clinical proof-of-concept tool that uses the five most predictive models and simplifies understanding of them through a web-based application.

Plasma Sphingolipid Profile Associated With Subclinical Atherosclerosis and Clinical Disease Markers of Systemic Lupus Erythematosus: Potential Predictive Value.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that affects females more than males, with African Americans developing more severe manifestation of the disease. SLE patients are at increased risk for cardiovascular disease (CVD), and SLE women 35-44 years old have 50 fold the incidence rate of CVD. Because SLE patients do not follow the typical age and gender pattern for CVD, but instead an accelerated disease course, the traditional biomarkers of elevated LDL and total cholesterol levels do not accurately assess their CVD risk. Recently, we have reported that African American SLE patients had higher ceramide, hexosylceramide, sphingosine and dihydrosphingosine 1-phosphate levels compared to their healthy controls, and those with atherosclerosis had higher sphingomyelin and sphingoid bases levels than those without (PLoS One. 2019; e0224496). In the current study, we sought to identify sphingolipid species that correlate with and pose the potential to predict atherosclerosis severity in African American SLE patients. Plasma samples from a group of African American predominantly female SLE patients with well-defined carotid atherosclerotic plaque burden were analyzed for sphingolipidomics using targeted mass spectroscopy. The data demonstrated that at baseline, plaque area and C3 values correlated inversely with most lactoceramide species. After one-year follow-up visit, values of the change of plaque area correlated positively with the lactoceramide species. There was no correlation between LDL-C concentrations and lactoceramide species. Taken together, lactocylcermide levels may have a 'predictive' value and sphingolipidomics have an added benefit to currently available tools in early diagnosis and prognosis of African American SLE patients with CVD.

The Care-coordination Approach to Learning Lupus Self-Management: a patient navigator intervention for systemic lupus inpatients.

OBJECTIVE: The Care-coordination Approach to Learning Lupus Self-Management (CALLS) study was designed to improve SLE disease self-management. This study aims to assess the benefits of the intervention compared with existing lupus care. METHODS: Participants were randomly assigned to participate in 12-weekly phone sessions with the patient navigator that included structured educational content, care coordination and patient-centred support services, or a usual care control condition. Validated measures of health literacy, self-efficacy, patient activation and disease activity were collected. We used least squares means and linear mixed-effects regression models for each outcome variable to assess the changes in outcome, from baseline to postintervention and to estimate the difference in these changes between the intervention and control group. RESULTS: Thirty participants were enrolled and 14 were randomised to the treatment group. For perceived lupus self-efficacy, there was a significant increase in mean score for the intervention group, but not for the control group. With regard to disease activity, the experimental group experienced a slight decrease in mean flare score in the previous 3 months, whereas the control group experienced a slight increase, but this finding did not reach statistical significance. Trends were similar in self-reported global disease activity, but none of the findings were significant. Health literacy and patient activation measure scores remained largely unchanged throughout the study for the two groups. CONCLUSION: These findings suggest that the CALLS intervention may work to improve aspects of SLE disease self-management. Future research will be needed to validate these findings long-term. TRIAL REGISTRATION NUMBER: NCT04400240.

Camptothecin and Topotecan, Inhibitors of Transcription Factor Fli-1 and Topoisomerase, Markedly Ameliorate Lupus Nephritis in (NZB × NZW)F1 Mice and Reduce the Production of Inflammatory Mediators in Human Renal Cells.

OBJECTIVE: To examine the therapeutic effects of camptothecin (CPT) and topotecan (TPT), inhibitors of transcription factor Fli-1 and topoisomerase, on lupus nephritis in (NZB × NZW)F1 (NZBWF1) mice, and to examine the effects of CPT and TPT on inflammatory mediators in human renal cells. METHODS: Female NZBWF1 mice were treated with vehicle, cyclophosphamide (CYC), CPT (1 mg/kg or 2 mg/kg), or TPT (0.03 mg/kg, 0.1 mg/kg, or 0. 3 mg/kg) by intraperitoneal injection twice a week, beginning at the age of 25 weeks (n = 8-10 mice per group). Blood and urine were collected for monitoring autoantibodies and proteinuria. Mice were euthanized at 40 weeks, and renal pathology scores were assessed. Human renal endothelial and mesangial cells were treated with CPT or TPT, and cytokine expression was measured. RESULTS: None of the NZBWF1 mice treated with 1 mg/kg or 2 mg/kg of CPT or 0.3 mg/kg of TPT had proteinuria >100 mg/dl at the age of 40 weeks. One of 8 mice treated with 0.1 mg/kg of TPT and 1 of 10 mice treated with CYC had proteinuria >300 mg/dl, whereas 90% of the mice treated with vehicle had proteinuria >300 mg/dl. Compared to vehicle control, mice treated with 1 mg/kg or 2 mg/kg of CPT, 0.1 mg/kg or 0.3 mg/kg of TPT, or CYC had significantly prolonged survival, attenuated renal injury, diminished splenomegaly, reduced anti-double-stranded DNA autoantibody levels, and reduced IgG and C3 deposits in the glomeruli (all P < 0.05). Human renal cells treated with CPT or TPT had reduced expression of Fli-1 and decreased monocyte chemotactic protein 1 production following stimulation with interferon-α (IFNα) or IFNγ. CONCLUSION: Our findings indicate that low-dose CPT and TPT could be repurposed to treat lupus nephritis.

DEFINING THE MEDICAL RECORD: RELATIONSHIPS OF THE LEGAL MEDICAL RECORD, THE DESIGNATED RECORD SET, AND THE ELECTRONIC HEALTH RECORD.

Not so long ago, defining the "medical record" was simple. It was the paper chart-volume upon volume that captured the serial, dutifully recorded events of a person's health care at a hospital or physician's office. Entries were typically handwritten, dated and timed, and signed in ink with title (i.e., authenticated). Errors were easily identified by an authenticated strike-through. Similarly, the paper chart was synonymous with the legal medical record (LMR). In other words, a patient's paper chart was that patient's LMR by definition, even if critical data was omitted or irrelevant data was included. Fast-forward to 2021 and the use of technology for capturing the record of a patient's care. Technology has brought new challenges as well as successes. For example, pervasive and persistent mythologies include that 1) a patient's electronic health record (EHR) is the LMR, and 2) patient-specific EHR printouts to paper or disc-or displays on monitors-are necessarily equivalents to the paper chart of the 1980s. Neither are true. We now must define at the outset what is included in the LMR/designated record set to ensure the accuracy of what is retained and released.

Association Between the Anti-Aging Gene Klotho and Selected Rheumatologic Autoimmune Diseases.

Klotho long recognized for its role in anti-aging, is potentially implicated in the pathogenesis of rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis. Aging of the immune system coincides with the inability of the body to recognize self-antigens, which often leads to autoimmune responses. The role of Klotho in these autoimmune diseases should be of high interest; however, few articles have been published exploring the role of Klotho in the pathogenesis, organ involvement, or clinical manifestation of rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis. Herein, we discuss information gathered from peer-reviewed publications to describe the emerging role of Kl in these select rheumatologic autoimmune diseases.

Lupus serum induces inflammatory interaction with neutrophils in human glomerular endothelial cells.

OBJECTIVES: SLE is associated with endothelial cell dysfunction (ECD). Understanding how ECD leads to neutrophil infiltration into glomeruli is essential to finding therapeutic targets for SLE. The aim of this study is to determine the effect of SLE serum from patients with active disease to induce neutrophil adhesion to and chemotaxis towards glomerular endothelial cells and factors induced by serum that associate with neutrophil chemotaxis. METHODS: Patients with SLE had serum collected during paired longitudinal visits with lower and higher activity. 13 patients with SLE (5 SLE, 5 SLE with hypertension (HTN) and 3 SLE lupus nephritis (LN) and HTN), and 10 healthy controls (5 with and 5 without HTN) were examined. The adhesion of neutrophils to serum-treated human renal glomerular endothelial cells (HRGECs) or chemotaxis of neutrophils towards conditioned media from serum-treated HRGECs was determined, and levels of cytokines in this conditioned medium were quantified. Pathway analysis of cytokines induced by SLE and LN serum that associated with neutrophil migration was performed. RESULTS: HRGECs treated with SLE serum induced significantly greater neutrophil chemotaxis and adhesion compared with control serum. When examining specific cohorts, SLE HTN and LN HTN promoted greater neutrophil chemotaxis than control serum, while SLE HTN and LN HTN promoted greater chemotaxis than SLE serum. Serum from active disease visits promoted neutrophil chemotaxis and adhesion over paired inactive visits. Levels of platelet-derived growth factor-BB, interleukin (IL)-15 and IL-8 secreted by SLE serum-treated HRGECs positively correlated with neutrophil chemotaxis. Pathway analysis suggested that LN serum induced pathways important in endoplasmic reticulum and oxidative stress. CONCLUSIONS: SLE serum induces expression of mediators by HRGECs that promote neutrophil chemotaxis and adhesion, which increases during disease activity, and associates with factors common to pathways of endoplasmic reticulum and oxidative stress. These findings highlight the potential importance of serum factor-induced ECD in SLE and LN.

ASSOCIATIONS BETWEEN ACCELERATED ATHEROSCLEROSIS, OXIDIZED LDL IMMUNE COMPLEXES, AND IN VITRO ENDOTHELIAL DYSFUNCTION IN SYSTEMIC LUPUS ERYTHEMATOSUS.

Systemic lupus erythematosus (SLE) is an independent risk factor for atherosclerosis. This study was designed to determine the association between atherosclerosis, oxidized LDL immune complexes (oxLDL-IC), and endothelial dysfunction in SLE. SLE patients were recruited, and carotid atherosclerotic total plaque area (TPA) was determined by ultrasound. Levels of oxLDL-IC were measured. In vitro endothelial function was measured by aortic endothelial nitric oxide (NO) production after culture of human aortic endothelial cells (HAEC) with SLE serum. Levels of oxLDL-IC are associated significantly with TPA. In vitro HAEC NO production after culture with SLE serum was positively correlated with serum complement. HAEC NO production was increased with sepiapterin to couple eNOS. To our knowledge, this is the first study to demonstrate an association between subclinical accelerated atherosclerosis and oxLDL-IC in SLE. This is also the first study to demonstrate the effect of sepiapterin on improving in vitro aortic endothelial cell function in SLE.

Variable selection methods for identifying predictor interactions in data with repeatedly measured binary outcomes.

INTRODUCTION: Identifying predictors of patient outcomes evaluated over time may require modeling interactions among variables while addressing within-subject correlation. Generalized linear mixed models (GLMMs) and generalized estimating equations (GEEs) address within-subject correlation, but identifying interactions can be difficult if not hypothesized a priori. We evaluate the performance of several variable selection approaches for clustered binary outcomes to provide guidance for choosing between the methods. METHODS: We conducted simulations comparing stepwise selection, penalized GLMM, boosted GLMM, and boosted GEE for variable selection considering main effects and two-way interactions in data with repeatedly measured binary outcomes and evaluate a two-stage approach to reduce bias and error in parameter estimates. We compared these approaches in real data applications: hypothermia during surgery and treatment response in lupus nephritis. RESULTS: Penalized and boosted approaches recovered correct predictors and interactions more frequently than stepwise selection. Penalized GLMM recovered correct predictors more often than boosting, but included many spurious predictors. Boosted GLMM yielded parsimonious models and identified correct predictors well at large sample and effect sizes, but required excessive computation time. Boosted GEE was computationally efficient and selected relatively parsimonious models, offering a compromise between computation and parsimony. The two-stage approach reduced the bias and error in regression parameters in all approaches. CONCLUSION: Penalized and boosted approaches are effective for variable selection in data with clustered binary outcomes. The two-stage approach reduces bias and error and should be applied regardless of method. We provide guidance for choosing the most appropriate method in real applications.

Rigorous Plasma Microbiome Analysis Method Enables Disease Association Discovery in Clinic.

Blood microbiome is important to investigate microbial-host interactions and the effects on systemic immune perturbations. However, this effort has met with major challenges due to low microbial biomass and background artifacts. In the current study, microbial 16S DNA sequencing was applied to analyze plasma microbiome. We have developed a quality-filtering strategy to evaluate and exclude low levels of microbial sequences, potential contaminations, and artifacts from plasma microbial 16S DNA sequencing analyses. Furthermore, we have applied our technique in three cohorts, including tobacco-smokers, HIV-infected individuals, and individuals with systemic lupus erythematosus (SLE), as well as corresponding controls. More than 97% of total sequence data was removed using stringent quality-filtering strategy analyses; those removed amplicon sequence variants (ASVs) were low levels of microbial sequences, contaminations, and artifacts. The specifically enriched pathobiont bacterial ASVs have been identified in plasmas from tobacco-smokers, HIV-infected individuals, and individuals with SLE but not from control subjects. The associations between these ASVs and disease pathogenesis were demonstrated. The pathologic activities of some identified bacteria were further verified in vitro. We present a quality-filtering strategy to identify pathogenesis-associated plasma microbiome. Our approach provides a method for studying the diagnosis of subclinical microbial infection as well as for understanding the roles of microbiome-host interaction in disease pathogenesis.

Peer approaches to self-management (PALS): comparing a peer mentoring approach for disease self-management in African American women with lupus with a social support control: study protocol for a randomized controlled trial.

BACKGROUND: Systemic lupus erythematosus (SLE or lupus) is a chronic autoimmune disease that is associated with increased morbidity, mortality, healthcare costs and decreased quality of life. African Americans in the USA have three to four times greater prevalence of SLE, risk of developing SLE at an earlier age, and SLE-related disease activity, damage, and mortality compared with Caucasians, with the highest rates experienced by African American women. There is strong evidence that patient-level factors are associated with outcomes, which justifies targeting them with intervention. While evidence-based self-management interventions that incorporate both social support and health education have reduced pain, improved function, and delayed disability among patients with SLE, African Americans and women are still disproportionately impacted by SLE. Peer mentoring interventions are effective in other chronic conditions that disproportionately affect minorities, such as diabetes mellitus, HIV, and kidney disease, but there is currently no empirically tested peer mentoring intervention developed for patients with SLE. Preliminary data from our group suggest that peer mentoring improves self-management, reduces disease activity, and improves health-related quality of life (HRQOL) in African American women with SLE. METHODS: This study will test an innovative, manualized peer mentorship program designed to provide modeling and reinforcement by peers (mentors) to other African American women with SLE (mentees) to encourage them to engage in activities that promote disease self-management. Through a randomized, "mentored" or "support group" controlled design, we will assess the efficacy and mechanism(s) of this intervention in self-management, disease activity, and HRQOL. DISCUSSION: This is the first study to test peer mentorship as an alternative strategy to improve outcomes in African American women with SLE. This could result in a model for other programs that aim to improve disease self-management, disease activity, and HRQOL in African American women suffering from chronic illness. The peer mentoring approach is uniquely fitted to African Americans, and this intervention has the potential to lead to health improvements for African American women with SLE that have not been attainable with other interventions. This would significantly reduce disparities and have considerable public health impact. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03734055 . Registered on 27 November 2018.

Progesterone decreases gut permeability through upregulating occludin expression in primary human gut tissues and Caco-2 cells.

Progesterone plays a protective role in preventing inflammation and preterm delivery during pregnancy. However, the mechanism involved is unknown. Microbial product translocation from a permeable mucosa is demonstrated as a driver of inflammation. To study the mechanism of the protective role of progesterone during pregnancy, we investigated the effect of physiologic concentrations of progesterone on tight junction protein occludin expression and human gut permeability in vitro and systemic microbial translocation in pregnant women in vivo. Plasma bacterial lipopolysaccharide (LPS), a representative marker of in vivo systemic microbial translocation was measured. We found that plasma LPS levels were significantly decreased during 24 to 28 weeks of gestation compared to 8 to 12 weeks of gestation. Moreover, plasma LPS levels were negatively correlated with plasma progesterone levels but positively correlated with plasma tumor necrosis factor-alpha (TNF-α) levels at 8 to 12 weeks of gestation but not at 24 to 28 weeks of gestation. Progesterone treatment increased intestinal trans-epithelial electrical resistance (TEER) in primary human colon tissues and Caco-2 cells in vitro through upregulating tight junction protein occludin expression. Furthermore, progesterone exhibited an inhibitory effect on nuclear factor kappa B (NF-κB) activation following LPS stimulation in Caco-2 cells. These results reveal a novel mechanism that progesterone may play an important role in decreasing mucosal permeability, systemic microbial translocation, and inflammation during pregnancy.