A multiomic analysis to identify drivers of subclinical vascular disease in systemic lupus erythematosus.

BACKGROUND: SLE increases cardiovascular disease (CVD) risk, not accounted by traditional risk factors. Characterization of blood immunological signatures that associate with subclinical CVD and predict its progression has been challenging and may help identify subgroups at risk. METHODS: SLE patients (n=77) and healthy controls (HC n=27) underwent assessments of arterial stiffness, vascular wall inflammation and coronary atherosclerosis burden with cardio-ankle vascular index (CAVI), fluorodeoxyglucose-positron emission tomography/CT (TBR), and coronary CT-angiography, respectively. Whole-blood bulk RNA-sequencing was performed in a subset of subjects (HC n=10, SLE n=20). In a partially overlapping subset (HC n=24, SLE n=64), serum inflammatory protein biomarkers were quantified with an Olink platform. RESULTS: CAVI, TBR and noncalcified coronary plaque burden (NCB) were increased in SLE compared to HC. When comparing SLE patients with high CAVI with those with low CAVI or with HCs, there was downregulation of genes in pathways involved in cell cycle, and differentially regulated pathways related to metabolism, respectively. Distinct serum proteins associated with increased CAVI (CCL23, CSF-1, LAP TFG-beta-1, IL33, CD8A and IL-12B), NCB (MCP-4 and Flt3L) and TBR (CD5, IL-1alpha, AXIN1, CST5 and TNFRSF9; P<0.05). CONCLUSIONS: Blood gene expression patterns and serum proteins that associate with worse vascular phenotypes suggest dysregulated immune and metabolic pathways linked to premature CVD. Cytokines and chemokines identified in associations with arterial stiffness, inflammation and NCB in SLE may allow for characterization of new CVD biomarkers in lupus.

Peroxisome proliferator activated receptor-γ agonist pioglitazone improves vascular and metabolic dysfunction in systemic lupus erythematosus.

OBJECTIVES: Premature cardiovascular events in systemic lupus erythematosus (SLE) contribute to morbidity and mortality, with no effective preventive strategies described to date. Immune dysregulation and metabolic disturbances appear to play prominent roles in the induction of vascular disease in SLE. The peroxisome proliferator activated receptor-gamma agonist pioglitazone (PGZ suppresses vascular damage and immune dysregulation in murine lupus and improves endothelial dysfunction in other inflammatory diseases. We hypothesised that PGZ could improve vascular dysfunction and cardiometabolic parameters in SLE. METHODS: Eighty SLE subjects with mild to severe disease activity were randomised to a sequence of PGZ followed by placebo for 3 months, or vice versa, in a double-blind, cross-over design with a 2-month wash-out period. Primary endpoints were parameters of endothelial function and arterial inflammation, measured by multimodal assessments. Additional outcome measures of disease activity, neutrophil dysregulation, metabolic disturbances and gene expression studies were performed. RESULTS: Seventy-two subjects completed the study. PGZ was associated with a significant reduction in Cardio-Ankle Vascular Index (a measure of arterial stiffness) compared with placebo. Various metabolic parameters improved with PGZ, including insulin resistance and lipoprotein profiles. Circulating neutrophil extracellular trap levels also significantly decreased with PGZ compared with placebo. Most adverse events experienced while on PGZ were mild and resolved with reduction in PGZ dose. CONCLUSION: PGZ was well tolerated and induced significant improvement in vascular stiffness and cardiometabolic parameters in SLE. The results suggest that PGZ should be further explored as a modulator of cardiovascular disease risk in SLE. TRIAL REGISTRATION NUMBER: NCT02338999.

Phase 1 double-blind randomized safety trial of the Janus kinase inhibitor tofacitinib in systemic lupus erythematosus.

Increased risk of premature cardiovascular disease (CVD) is well recognized in systemic lupus erythematosus (SLE). Aberrant type I-Interferon (IFN)-neutrophil interactions contribute to this enhanced CVD risk. In lupus animal models, the Janus kinase (JAK) inhibitor tofacitinib improves clinical features, immune dysregulation and vascular dysfunction. We conducted a randomized, double-blind, placebo-controlled clinical trial of tofacitinib in SLE subjects (ClinicalTrials.gov NCT02535689). In this study, 30 subjects are randomized to tofacitinib (5 mg twice daily) or placebo in 2:1 block. The primary outcome of this study is safety and tolerability of tofacitinib. The secondary outcomes include clinical response and mechanistic studies. The tofacitinib is found to be safe in SLE meeting study's primary endpoint. We also show that tofacitinib improves cardiometabolic and immunologic parameters associated with the premature atherosclerosis in SLE. Tofacitinib improves high-density lipoprotein cholesterol levels (p = 0.0006, CI 95%: 4.12, 13.32) and particle number (p = 0.0008, CI 95%: 1.58, 5.33); lecithin: cholesterol acyltransferase concentration (p = 0.024, CI 95%: 1.1, -26.5), cholesterol efflux capacity (p = 0.08, CI 95%: -0.01, 0.24), improvements in arterial stiffness and endothelium-dependent vasorelaxation and decrease in type I IFN gene signature, low-density granulocytes and circulating NETs. Some of these improvements are more robust in subjects with STAT4 risk allele.

Association of lipoprotein subfractions and glycoprotein acetylation with coronary plaque burden in SLE.

OBJECTIVE: Subjects with SLE display an enhanced risk of atherosclerotic cardiovascular disease (CVD) that is not explained by Framingham risk. This study sought to investigate the utility of nuclear MR (NMR) spectroscopy measurements of serum lipoprotein particle counts and size and glycoprotein acetylation (GlycA) burden to predict coronary atherosclerosis in SLE. METHODS: Coronary plaque burden was assessed in SLE subjects and healthy controls using coronary CT angiography. Lipoproteins and GlycA were quantified by NMR spectroscopy. RESULTS: SLE subjects displayed statistically significant decreases in high-density lipoprotein (HDL) particle counts and increased very low-density lipoprotein (VLDL) particle counts compared with controls. Non-calcified coronary plaque burden (NCB) negatively associated with HDL subsets whereas it positively associated with VLDL particle counts in multivariate adjusted models. GlycA was significantly increased in SLE sera compared with controls. In contrast to high-sensitivity C reactive protein, elevations in GlycA in SLE significantly associated with NCB and insulin resistance (IR), though the association with NCB was no longer significant after adjusting for prednisone use. CONCLUSIONS: Patients with SLE display a proatherogenic lipoprotein profile that may significantly contribute to the development of premature CVD. The results demonstrate that NMR measures of GlycA and lipoprotein profiles, beyond what is captured in routine clinical labs, could be a useful tool in assessing CVD risk in patients with SLE.

Safety and Tolerability of Omalizumab: A Randomized Clinical Trial of Humanized Anti-IgE Monoclonal Antibody in Systemic Lupus Erythematosus.

OBJECTIVE: Autoreactive IgE antibodies have been implicated in the pathogenesis of systemic lupus erythematosus (SLE). We hypothesize that omalizumab, a monoclonal antibody binding IgE, may improve SLE activity by reducing type I interferon (IFN) production by hampering plasmacytoid dendritic cells and basophil activation. This study was undertaken to assess the safety, tolerability, and clinical efficacy of omalizumab in mild to moderate SLE. METHODS: Sixteen subjects with SLE and a Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score of ≥4 and elevated autoreactive IgE antibody levels were randomized to receive omalizumab or placebo (2:1) for 16 weeks, followed by 16 weeks of open-label treatment and a 4-week washout period. The SLEDAI-2K score, British Isles Lupus Assessment Group index (BILAG 2004) score, and physician's global assessment of disease activity were recorded at each visit. The type I IFN-induced gene signature was determined using quantitative polymerase chain reaction. RESULTS: Omalizumab was well tolerated with no allergic reactions, and mostly mild adverse events comparable to those experienced with placebo treatment. SLEDAI-2K scores improved in the omalizumab group compared to the placebo group at week 16 (P = 0.038), as well as during the open-label phase in subjects initially receiving placebo (P = 0.02). No worsening in BILAG scores or the physician's global assessment was detected. There was a trend toward a reduction in IFN gene signature in subjects treated with omalizumab (P = 0.11), especially in subjects with a high baseline IFN signature (P = 0.052). CONCLUSION: Our findings indicate that omalizumab is well tolerated in SLE and is associated with improvement in disease activity. Larger randomized clinical trials will be needed to assess the efficacy of omalizumab in patients with SLE.

Neutrophil subsets and their gene signature associate with vascular inflammation and coronary atherosclerosis in lupus.

BACKGROUND: Systemic lupus erythematosus (SLE) is associated with enhanced risk of atherosclerotic cardiovascular disease not explained by Framingham risk score (FRS). Immune dysregulation associated to a distinct subset of lupus proinflammatory neutrophils (low density granulocytes; LDGs) may play key roles in conferring enhanced CV risk. This study assessed if lupus LDGs are associated with in vivo vascular dysfunction and inflammation and coronary plaque. METHODS: SLE subjects and healthy controls underwent multimodal phenotyping of vascular disease by quantifying vascular inflammation (18F-fluorodeoxyglucose-PET/CT [18F-FDG-PET/CT]), arterial dysfunction (EndoPAT and cardio-ankle vascular index), and coronary plaque burden (coronary CT angiography). LDGs were quantified by flow cytometry. Cholesterol efflux capacity was measured in high-density lipoprotein-exposed (HDL-exposed) radioactively labeled cell lines. Whole blood RNA sequencing was performed to assess associations between transcriptomic profiles and vascular phenotype. RESULTS: Vascular inflammation, arterial stiffness, and noncalcified plaque burden (NCB) were increased in SLE compared with controls even after adjustment for traditional risk factors. In SLE, NCB directly associated with LDGs and associated negatively with cholesterol efflux capacity in fully adjusted models. A neutrophil gene signature reflective of the most upregulated genes in lupus LDGs associated with vascular inflammation and NCB. CONCLUSION: Individuals with SLE demonstrate vascular inflammation, arterial dysfunction, and NCB, which may explain the higher reported risk for acute coronary syndromes. The association of LDGs and neutrophil genes with vascular disease supports the hypothesis that distinct neutrophil subsets contribute to vascular damage and unstable coronary plaque in SLE. Results also support previous observations that neutrophils may disrupt HDL function and thereby promote atherogenesis. TRIAL REGISTRATION: Clinicaltrials.gov NCT00001372FUNDING. Intramural Research Program NIAMS/NIH (ZIA AR041199) and Lupus Research Institute.