Phase 3, multicentre, randomised, placebo-controlled study evaluating the efficacy and safety of ustekinumab in patients with systemic lupus erythematosus.

OBJECTIVE: Evaluate the efficacy and safety of ustekinumab, an anti-interleukin-12/23 p40 antibody, in a phase 3, randomised, placebo-controlled study of patients with active systemic lupus erythematosus (SLE) despite receiving standard-of-care. METHODS: Active SLE patients (SLE Disease Activity Index 2000 (SLEDAI-2K) ≥6 during screening and SLEDAI-2K ≥4 for clinical features at week 0) despite receiving oral glucocorticoids, antimalarials, or immunomodulatory drugs were randomised (3:2) to receive ustekinumab (intravenous infusion ~6 mg/kg at week 0, followed by subcutaneous injections of ustekinumab 90 mg at week 8 and every 8 weeks) or placebo through week 48. The primary endpoint was SLE Responder Index (SRI)-4 at week 52, and major secondary endpoints included time to flare through week 52 and SRI-4 at week 24. RESULTS: At baseline, 516 patients were randomised to placebo (n=208) or ustekinumab (n=308). Following the planned interim analysis, the sponsor discontinued the study due to lack of efficacy but no safety concerns. Efficacy analyses included 289 patients (placebo, n=116; ustekinumab, n=173) who completed or would have had a week 52 visit at study discontinuation. At week 52, 44% of ustekinumab patients and 56% of placebo patients had an SRI-4 response; there were no appreciable differences between the treatment groups in the major secondary endpoints. Through week 52, 28% of ustekinumab patients and 32% of placebo patients had a British Isles Lupus Assessment Group flare, with a mean time to first flare of 204.7 and 200.4 days, respectively. Through week 52, 70% of ustekinumab patients and 74% of placebo patients had ≥1 adverse event. CONCLUSIONS: Ustekinumab did not demonstrate superiority over placebo in this population of adults with active SLE; adverse events were consistent with the known safety profile of ustekinumab. TRIAL REGISTRATION NUMBER: NCT03517722.

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.

Efficacy and safety of ustekinumab, an IL-12 and IL-23 inhibitor, in patients with active systemic lupus erythematosus: results of a multicentre, double-blind, phase 2, randomised, controlled study.

BACKGROUND: Ustekinumab is a monoclonal antibody targeting interleukin (IL)-12 and IL-23 and is approved for the treatment of plaque psoriasis, psoriatic arthritis, and Crohn's disease. IL-12 and IL-23 have been implicated in systemic lupus erythematosus. We aimed to assess the efficacy and safety of ustekinumab for the treatment of systemic lupus erythematosus in patients with moderate-to-severe disease activity despite conventional treatment. METHODS: This was a multicentre, double-blind, phase 2, randomised, controlled trial of adult patients with active, seropositive systemic lupus erythematosus, done at 44 private practices and academic centres in Argentina, Australia, Germany, Hungary, Mexico, Poland, Spain, Taiwan, and the USA. Eligible adults were aged 18-75 years, weighed at least 35 kg, and had a diagnosis of systemic lupus erythematosus at least 3 months before the first administration of study drug. Eligible patients were randomly assigned (3:2) to the ustekinumab or placebo group using an interactive web response system with stratification by skin biopsy, lupus nephritis presence, baseline systemic lupus erythematosus medications and systemic lupus erythematosus disease activity index 2000 (SLEDAI-2K) score combined factor, site, region, and race. Patients and investigators were masked to treatment allocation. Patients received an intravenous infusion of ustekinumab (260 mg for patients weighing 35-55 kg, 390 mg for patients weighing >55 kg and ≤85 kg, and 520 mg for patients weighing >85 kg) followed by subcutaneous injections of ustekinumab 90 mg every 8 weeks or intravenous infusion of placebo at week 0 followed by subcutaneous injections of placebo every 8 weeks, both in addition to standard-of-care therapy. The primary endpoint was the proportion of patients achieving a SLEDAI-2K responder index-4 (SRI-4) response at week 24. Efficacy analyses were done in a modified intention-to-treat population of patients who received at least one dose (partial or complete, intravenous or subcutaneous) of their randomly assigned study treatment. Safety analyses were done in all patients who received at least one dose of study treatment, regardless of group assignment. This study is registered at ClinicalTrials.gov, number NCT02349061. FINDINGS: Between Oct 6, 2015, and Nov 30, 2016, 166 patients were screened, of whom 102 were randomly assigned to receive ustekinumab (n=60) or placebo (n=42). At week 24, 37 (62%) of 60 patients in the ustekinumab group and 14 (33%) of 42 patients in the placebo group achieved an SRI-4 response (percentage difference 28% [95% CI 10-47], p=0·006). Between week 0 and week 24, 47 (78%) of 60 patients in the ustekinumab group and 28 (67%) of 42 patients in the placebo group had at least one adverse event. Infections were the most common type of adverse event (27 [45%] in the ustekinumab group vs 21 [50%] in the placebo group). No deaths or treatment-emergent opportunistic infections, herpes zoster, tuberculosis, or malignancies occurred between weeks 0-24. INTERPRETATION: The addition of ustekinumab to standard-of-care treatment resulted in better efficacy in clinical and laboratory parameters than placebo in the treatment of active systemic lupus erythematosus and had a safety profile consistent with ustekinumab therapy in other diseases. The results of this study support further development of ustekinumab as a novel treatment in systemic lupus erythematosus. FUNDING: Janssen Research & Development, LLC.

Decreased SMG7 expression associates with lupus-risk variants and elevated antinuclear antibody production.

OBJECTIVES: Following up the systemic lupus erythematosus (SLE) genome-wide association studies (GWAS) identification of NMNAT2 at rs2022013, we fine-mapped its 150 kb flanking regions containing NMNAT2 and SMG7 in a 15 292 case-control multi-ancestry population and tested functions of identified variants. METHODS: We performed genotyping using custom array, imputation by IMPUTE 2.1.2 and allele specific functions using quantitative real-time PCR and luciferase reporter transfections. SLE peripheral blood mononuclear cells (PBMCs) were cultured with small interfering RNAs to measure antinuclear antibody (ANA) and cyto/chemokine levels in supernatants using ELISA. RESULTS: We confirmed association at NMNAT2 in European American (EA) and Amerindian/Hispanic ancestries, and identified independent signal at SMG7 tagged by rs2702178 in EA only (p=2.4×10-8, OR=1.23 (95% CI 1.14 to 1.32)). In complete linkage disequilibrium with rs2702178, rs2275675 in the promoter region robustly associated with SMG7 mRNA levels in multiple expression quantitative trait locus (eQTL) datasets. Its risk allele was dose-dependently associated with decreased SMG7 mRNA levels in PBMCs of 86 patients with SLE and 119 controls (p=1.1×10-3 and 6.8×10-8, respectively) and conferred reduced transcription activity in transfected HEK-293 (human embryonic kidney cell line) and Raji cells (p=0.0035 and 0.0037, respectively). As a critical component in the nonsense-mediated mRNA decay pathway, SMG7 could regulate autoantigens including ribonucleoprotein (RNP) and Smith (Sm). We showed SMG7 mRNA levels in PBMCs correlated inversely with ANA titres of patients with SLE (r=-0.31, p=0.01), and SMG7 knockdown increased levels of ANA IgG and chemokine (C-C motif) ligand 19 in SLE PBMCs (p=2.0×10-5 and 2.0×10-4, respectively). CONCLUSION: We confirmed NMNAT2 and identified independent SMG7 association with SLE. The inverse relationship between levels of the risk allele-associated SMG7 mRNAs and ANA suggested the novel contribution of mRNA surveillance pathway to SLE pathogenesis.

MicroRNA-3148 modulates allelic expression of toll-like receptor 7 variant associated with systemic lupus erythematosus.

We previously reported that the G allele of rs3853839 at 3'untranslated region (UTR) of Toll-like receptor 7 (TLR7) was associated with elevated transcript expression and increased risk for systemic lupus erythematosus (SLE) in 9,274 Eastern Asians [P = 6.5×10(-10), odds ratio (OR) (95%CI) = 1.27 (1.17-1.36)]. Here, we conducted trans-ancestral fine-mapping in 13,339 subjects including European Americans, African Americans, and Amerindian/Hispanics and confirmed rs3853839 as the only variant within the TLR7-TLR8 region exhibiting consistent and independent association with SLE (Pmeta = 7.5×10(-11), OR = 1.24 [1.18-1.34]). The risk G allele was associated with significantly increased levels of TLR7 mRNA and protein in peripheral blood mononuclear cells (PBMCs) and elevated luciferase activity of reporter gene in transfected cells. TLR7 3'UTR sequence bearing the non-risk C allele of rs3853839 matches a predicted binding site of microRNA-3148 (miR-3148), suggesting that this microRNA may regulate TLR7 expression. Indeed, miR-3148 levels were inversely correlated with TLR7 transcript levels in PBMCs from SLE patients and controls (R(2) = 0.255, P = 0.001). Overexpression of miR-3148 in HEK-293 cells led to significant dose-dependent decrease in luciferase activity for construct driven by TLR7 3'UTR segment bearing the C allele (P = 0.0003). Compared with the G-allele construct, the C-allele construct showed greater than two-fold reduction of luciferase activity in the presence of miR-3148. Reduced modulation by miR-3148 conferred slower degradation of the risk G-allele containing TLR7 transcripts, resulting in elevated levels of gene products. These data establish rs3853839 of TLR7 as a shared risk variant of SLE in 22,613 subjects of Asian, EA, AA, and Amerindian/Hispanic ancestries (Pmeta  = 2.0×10(-19), OR = 1.25 [1.20-1.32]), which confers allelic effect on transcript turnover via differential binding to the epigenetic factor miR-3148.

Preferential binding to Elk-1 by SLE-associated IL10 risk allele upregulates IL10 expression.

Immunoregulatory cytokine interleukin-10 (IL-10) is elevated in sera from patients with systemic lupus erythematosus (SLE) correlating with disease activity. The established association of IL10 with SLE and other autoimmune diseases led us to fine map causal variant(s) and to explore underlying mechanisms. We assessed 19 tag SNPs, covering the IL10 gene cluster including IL19, IL20 and IL24, for association with SLE in 15,533 case and control subjects from four ancestries. The previously reported IL10 variant, rs3024505 located at 1 kb downstream of IL10, exhibited the strongest association signal and was confirmed for association with SLE in European American (EA) (P = 2.7×10⁻8, OR = 1.30), but not in non-EA ancestries. SNP imputation conducted in EA dataset identified three additional SLE-associated SNPs tagged by rs3024505 (rs3122605, rs3024493 and rs3024495 located at 9.2 kb upstream, intron 3 and 4 of IL10, respectively), and SLE-risk alleles of these SNPs were dose-dependently associated with elevated levels of IL10 mRNA in PBMCs and circulating IL-10 protein in SLE patients and controls. Using nuclear extracts of peripheral blood cells from SLE patients for electrophoretic mobility shift assays, we identified specific binding of transcription factor Elk-1 to oligodeoxynucleotides containing the risk (G) allele of rs3122605, suggesting rs3122605 as the most likely causal variant regulating IL10 expression. Elk-1 is known to be activated by phosphorylation and nuclear localization to induce transcription. Of interest, phosphorylated Elk-1 (p-Elk-1) detected only in nuclear extracts of SLE PBMCs appeared to increase with disease activity. Co-expression levels of p-Elk-1 and IL-10 were elevated in SLE T, B cells and monocytes, associated with increased disease activity in SLE B cells, and were best downregulated by ERK inhibitor. Taken together, our data suggest that preferential binding of activated Elk-1 to the IL10 rs3122605-G allele upregulates IL10 expression and confers increased risk for SLE in European Americans.

Paraoxonase-3 is depleted from the high-density lipoproteins of autoimmune disease patients with subclinical atherosclerosis.

Patients with autoimmune diseases have a significantly increased risk of developing cardiovascular disease. In disease, high-density lipoprotein (HDL) particles lose their anti-inflammatory and antioxidant properties and become dysfunctional. The purpose of this study was to test the hypothesis that alterations in the HDL proteomic profile are associated with subclinical atherosclerosis and HDL dysfunction in patients with autoimmune diseases such as systemic lupus erythematosus (SLE) and type 1 diabetes. Targeted proteomics was used to quantify the relative abundance of 18 proteins in HDL from SLE patients with and without atherosclerotic plaque detectable by carotid ultrasound. Changes in the proteomic profile were compared against the in vitro ability of HDL to protect against lipid oxidation. The same proteins were quantified in HDL from patients with type 1 diabetes with or without coronary artery calcification as determined by computed tomography. In each population, paraoxonase-3 (PON3), a potent antioxidant protein, was depleted from the HDL of patients with subclinical atherosclerosis. PON3 expression in HDL was positively correlated with HDL antioxidant function. These results suggest that PON3 may be an important protein in preventing atherosclerosis and highlight the importance of antioxidant proteins in the prevention of atherosclerosis in vivo.

Genetic associations of leptin-related polymorphisms with systemic lupus erythematosus.

Leptin is abnormally elevated in the plasma of patients with systemic lupus erythematosus (SLE), where it is thought to promote and/or sustain pro-inflammatory responses. Whether this association could reflect an increased genetic susceptibility to develop SLE is not known, and studies of genetic associations with leptin-related polymorphisms in SLE patients have been so far inconclusive. Here we genotyped DNA samples from 15,706 SLE patients and healthy matched controls from four different ancestral groups, to correlate polymorphisms of genes of the leptin pathway to risk for SLE. It was found that although several SNPs showed weak associations, those associations did not remain significant after correction for multiple testing. These data do not support associations between defined leptin-related polymorphisms and increased susceptibility to develop SLE.

Blockade of programmed death-1 in young (New Zealand Black x New Zealand White)F1 mice promotes the suppressive capacity of CD4+ regulatory T cells protecting from lupus-like disease.

Programmed death-1 (PD-1) usually acts as a negative signal for T cell activation, and its expression on CD8(+)Foxp3(+) T cells is required for their suppressive capacity. In this study, we show that PD-1 signaling is required for the maintenance of functional regulatory CD4(+)CD25(+)Foxp3(+) regulatory T cells (CD4(+) T(reg)) that can control autoimmunity in (New Zealand Black × New Zealand White)F1 lupus mice. PD-1 signaling induced resistance to apoptosis and prolonged the survival of CD4(+) T(reg). In vivo, the blockade of PD-1 with a neutralizing Ab reduced PD-1 expression on CD4(+) T(reg) (PD1(lo)CD4(+) T(reg)). PD1(lo)CD4(+) T(reg) had an increased ability to promote B cell apoptosis and to suppress CD4(+) Th as compared with CD4(+) T(reg) with elevated PD-1 expression (PD1(hi)CD4(+) T(reg)). When PD-1 expression on CD4(+) T(reg) was blocked in vitro, PD1(lo)CD4(+) T(reg) suppressed B cell production of IgG and anti-dsDNA Ab. Finally, in vitro studies showed that the suppressive capacity of CD4(+) T(reg) depended on PD-1 expression and that a fine-tuning of the expression of this molecule directly affected cell survival and immune suppression. These results indicate that PD-1 expression has multiple effects on different immune cells that directly contribute to a modulation of autoimmune responses.

Association of genetic variants in complement factor H and factor H-related genes with systemic lupus erythematosus susceptibility.

Systemic lupus erythematosus (SLE), a complex polygenic autoimmune disease, is associated with increased complement activation. Variants of genes encoding complement regulator factor H (CFH) and five CFH-related proteins (CFHR1-CFHR5) within the chromosome 1q32 locus linked to SLE, have been associated with multiple human diseases and may contribute to dysregulated complement activation predisposing to SLE. We assessed 60 SNPs covering the CFH-CFHRs region for association with SLE in 15,864 case-control subjects derived from four ethnic groups. Significant allelic associations with SLE were detected in European Americans (EA) and African Americans (AA), which could be attributed to an intronic CFH SNP (rs6677604, in intron 11, P(meta) = 6.6×10(-8), OR = 1.18) and an intergenic SNP between CFHR1 and CFHR4 (rs16840639, P(meta) = 2.9×10(-7), OR = 1.17) rather than to previously identified disease-associated CFH exonic SNPs, including I62V, Y402H, A474A, and D936E. In addition, allelic association of rs6677604 with SLE was subsequently confirmed in Asians (AS). Haplotype analysis revealed that the underlying causal variant, tagged by rs6677604 and rs16840639, was localized to a ~146 kb block extending from intron 9 of CFH to downstream of CFHR1. Within this block, the deletion of CFHR3 and CFHR1 (CFHR3-1Δ), a likely causal variant measured using multiplex ligation-dependent probe amplification, was tagged by rs6677604 in EA and AS and rs16840639 in AA, respectively. Deduced from genotypic associations of tag SNPs in EA, AA, and AS, homozygous deletion of CFHR3-1Δ (P(meta) = 3.2×10(-7), OR = 1.47) conferred a higher risk of SLE than heterozygous deletion (P(meta) = 3.5×10(-4), OR = 1.14). These results suggested that the CFHR3-1Δ deletion within the SLE-associated block, but not the previously described exonic SNPs of CFH, might contribute to the development of SLE in EA, AA, and AS, providing new insights into the role of complement regulators in the pathogenesis of SLE.

Fine mapping of Xq28: both MECP2 and IRAK1 contribute to risk for systemic lupus erythematosus in multiple ancestral groups.

OBJECTIVES: The Xq28 region containing IRAK1 and MECP2 has been identified as a risk locus for systemic lupus erythematosus (SLE) in previous genetic association studies. However, due to the strong linkage disequilibrium between IRAK1 and MECP2, it remains unclear which gene is affected by the underlying causal variant(s) conferring risk of SLE. METHODS: We fine-mapped ≥136 SNPs in a ∼227 kb region on Xq28, containing IRAK1, MECP2 and seven adjacent genes (L1CAM, AVPR2, ARHGAP4, NAA10, RENBP, HCFC1 and TMEM187), for association with SLE in 15 783 case-control subjects derived from four different ancestral groups. RESULTS: Multiple SNPs showed strong association with SLE in European Americans, Asians and Hispanics at p<5×10(-8) with consistent association in subjects with African ancestry. Of these, six SNPs located in the TMEM187-IRAK1-MECP2 region captured the underlying causal variant(s) residing in a common risk haplotype shared by all four ancestral groups. Among them, rs1059702 best explained the Xq28 association signals in conditional testings and exhibited the strongest p value in transancestral meta-analysis (p(meta )= 1.3×10(-27), OR=1.43), and thus was considered to be the most likely causal variant. The risk allele of rs1059702 results in the amino acid substitution S196F in IRAK1 and had previously been shown to increase NF-κB activity in vitro. We also found that the homozygous risk genotype of rs1059702 was associated with lower mRNA levels of MECP2, but not IRAK1, in SLE patients (p=0.0012) and healthy controls (p=0.0064). CONCLUSIONS: These data suggest contributions of both IRAK1 and MECP2 to SLE susceptibility.

Sex-specific association of X-linked Toll-like receptor 7 (TLR7) with male systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a multisystem, autoimmune disease that predominantly affects women. Previous findings that duplicated Toll-like receptor 7 (Tlr7) promotes lupus-like disease in male BXSB mice prompted us to evaluate TLR7 in human SLE. By using a candidate gene approach, we identified and replicated association of a TLR7 3'UTR SNP, rs3853839 (G/C), with SLE in 9,274 Eastern Asians (P(combined) = 6.5 x 10(-10)), with a stronger effect in male than female subjects [odds ratio, male vs. female = 2.33 (95% CI = 1.64-3.30) vs. 1.24 (95% CI = 1.14-1.34); P = 4.1 x 10(-4)]. G-allele carriers had increased TLR7 transcripts and more pronounced IFN signature than C-allele carriers; heterozygotes had 2.7-fold higher transcripts of G-allele than C-allele. These data established a functional polymorphism in type I IFN pathway gene TLR7 predisposing to SLE, especially in Chinese and Japanese male subjects.

Tolerance induced by anti-DNA Ig peptide in (NZB×NZW)F1 lupus mice impinges on the resistance of effector T cells to suppression by regulatory T cells.

We have previously shown that immune tolerance induced by the anti-DNA Ig peptide pCons in (NZB×NZW)F(1) (NZB/W) lupus mice prolonged survival of treated animals and delayed the appearance of autoantibodies and glomerulonephritis. Part of the protection conferred by pCons could be ascribed to the induction of regulatory T cells (T(Reg)) that suppressed the production of anti-DNA antibodies in a p38 MAPK-dependent fashion. Here we show that another effect of pCons in the induction of immune tolerance in NZB/W lupus mice is the facilitation of effector T cell suppression by T(Reg). These new findings indicate that pCons exerts protective effects in NZB/W lupus mice by differentially modulating the activity of different T cell subsets, implying new considerations in the design of T(Reg)-based approaches to modulate T cell autoreactivity in SLE.

Association of a functional IRF7 variant with systemic lupus erythematosus.

OBJECTIVE: A previous genome-wide association study conducted in a population of European ancestry identified rs4963128, a KIAA1542 single-nucleotide polymorphism (SNP) 23 kb telomeric to IRF7 (the gene for interferon regulatory factor 7 [IRF-7]), to be strongly associated with systemic lupus erythematosus (SLE). This study was undertaken to investigate whether genetic polymorphism within IRF7 is a risk factor for the development of SLE. METHODS: We genotyped one KIAA1542 SNP (rs4963128) and one IRF7 SNP (rs1131665 [Q412R]) in an Asian population (1,302 cases, 1,479 controls), to assess their association with SLE. Subsequently, rs1131665 was further genotyped in independent panels of Chinese subjects (528 cases, 527 controls), European American subjects (446 cases, 461 controls), and African American subjects (159 cases, 115 controls) by TaqMan genotyping assay, to seek confirmation of association in various ethnic groups. A luciferase reporter assay was used to assess the effect of Q412R polymorphism on the activation of IRF-7. RESULTS: Consistent association of rs1131665 (Q412R) with SLE was identified in Asian, European American, and African American populations (total 2,435 cases and 2,582 controls) (P(meta) = 6.18 × 10(-6) , odds ratio 1.42 [95% confidence interval 1.22-1.65]). Expression of the IRF7 412Q risk allele resulted in a 2-fold increase in interferon-stimulated response element transcriptional activity compared with expression of IRF7 412R (P = 0.0003), suggesting that IRF7 412Q confers elevated IRF-7 activity and may therefore affect a downstream interferon pathway. CONCLUSION: These findings show that the major allele of a nonsynonymous SNP, rs1131665 (412Q) in IRF7, confers elevated activation of IRF-7 and predisposes to the development of SLE in multiple ethnic groups. This result provides direct genetic evidence that IRF7 may be a risk gene for human SLE.

Association of PPP2CA polymorphisms with systemic lupus erythematosus susceptibility in multiple ethnic groups.

OBJECTIVE: T cells from patients with systemic lupus erythematosus (SLE) express increased amounts of PP2Ac, which contributes to decreased production of interleukin-2 (IL-2). Because IL-2 is important in the regulation of several aspects of the immune response, it has been proposed that PP2Ac contributes to the expression of SLE. This study was designed to determine whether genetic variants of PPP2AC are linked to the expression of SLE and specific clinical manifestations and account for the increased expression of PP2Ac. METHODS: We conducted a trans-ethnic study of 8,695 SLE cases and 7,308 controls of 4 different ancestries. Eighteen single-nucleotide polymorphisms (SNPs) across PPP2CA were genotyped using an Illumina custom array. PPP2CA expression in SLE and control T cells was analyzed by real-time polymerase chain reaction. RESULTS: A 32-kb haplotype comprising multiple SNPs of PPP2CA showed significant association with SLE in Hispanic Americans, European Americans, and Asians, but not in African Americans. Conditional analyses revealed that SNP rs7704116 in intron 1 showed consistently strong association with SLE across Asian, European American, and Hispanic American populations (odds ratio 1.3 [95% confidence interval 1.14-1.31], meta-analysis P=3.8×10(-7)). In European Americans, the largest ethnic data set studied, the risk A allele of rs7704116 was associated with the presence of renal disease, anti-double-stranded DNA, and anti-RNP antibodies. PPP2CA expression was ∼2-fold higher in SLE patients carrying the rs7704116 AG genotype than those carrying the GG genotype (P=0.007). CONCLUSION: Our data provide the first evidence of an association between PPP2CA polymorphisms and elevated PP2Ac transcript levels in T cells, which implicates a new molecular pathway for SLE susceptibility in European Americans, Hispanic Americans, and Asians.

Blockade of programmed death-1 in young (New Zealand black x New Zealand white)F1 mice promotes the activity of suppressive CD8+ T cells that protect from lupus-like disease.

The programmed death-1 (PD-1)/programmed death-1 ligand 1 (PD-L1) pathway regulates both stimulatory and inhibitory signals. In some conditions, PD-1/PD-L1 inhibits T and B cell activation, induces anergy, and reduces cytotoxicity in CD8(+) T cells. In other conditions, PD-l/PD-L1 has costimulatory effects on T cells. We recently showed that induction of suppressive CD8(+)Foxp3(+) T cells by immune tolerance of lupus-prone (New Zealand black × New Zealand white)F(1) (BWF(1)) mice with the anti-DNA Ig-based peptide pConsensus (pCons) is associated with significantly reduced PD-1 expression on those cells. In this study, we tested directly the role of PD-1 by administering in vivo neutralizing Ab to PD-1 to premorbid BWF(1) and healthy control mice. Anti-PD-1-treated mice were protected from the onset of lupus nephritis for 10 wk, with significantly improved survival. Although the numbers of T cells declined in aging control mice, they were maintained in anti-PD-1-treated mice, including CD8(+)Foxp3(+) T cells that suppressed syngeneic CD4(+)CD25(-) T cell proliferation and IFN-γ production, reduced production of IgG and anti-dsDNA IgG, induced apoptosis in syngeneic B cells, and increased IL-2 and TGF-ß production. The administration of anti-PD-1 Ab to BWF(1) mice after induction of tolerance with pCons abrogated tolerance; mice developed autoantibodies and nephritis at the same time as control mice, being unable to induce CD8(+)Foxp3(+) T suppressor cells. These data suggest that tightly regulated PD-1 expression is essential for the maintenance of immune tolerance mediated by those CD8(+)Foxp3(+) T cells that suppress both T(h) cells and pathogenic B cells. PD-1 regulation could represent a target to preserve tolerance and prevent autoimmunity.

Identification and Contribution of Inflammation-Induced Novel MicroRNA in the Pathogenesis of Systemic Lupus Erythematosus.

Recently microRNAs (miRNAs) have been recognized as powerful regulators of many genes and pathways involved in the pathogenesis of inflammatory diseases including Systemic Lupus Erythematosus (SLE). SLE is an autoimmune disease characterized by production of various autoantibodies, inflammatory immune cells, and dysregulation of epigenetic changes. Several candidate miRNAs regulating inflammation and autoimmunity in SLE are described. In this study, we found significant increases in the expression of miR21, miR25, and miR186 in peripheral blood mononuclear cells (PBMCs) of SLE patients compared to healthy controls. However, miR146a was significantly decreased in SLE patients compared to healthy controls and was negatively correlated with plasma estradiol levels and with SLE disease activity scores (SLEDAI). We also found that protein levels of IL-12 and IL-21 were significantly increased in SLE patients as compared to healthy controls. Further, our data shows that protein levels of IL-12 were positively correlated with miR21 expression and protein levels of IL-21 positively correlated with miR25 and miR186 expression in SLE patients. In addition, we found that levels of miR21, miR25, and miR186 positively correlated with SLEDAI and miR146a was negatively correlated in SLE patients. Thus, our data shows a dynamic interplay between disease pathogenesis and miRNA expression. This study has translational potential and may identify novel therapeutic targets in patients with SLE.

Efficacy and Safety of Ustekinumab in Patients With Active Systemic Lupus Erythematosus: Results of a Phase II Open-label Extension Study.

OBJECTIVE: To evaluate the long-term efficacy and safety of ustekinumab through 2 years in patients with active systemic lupus erythematosus (SLE). METHODS: This was a placebo-controlled (week 24), phase II study in 102 patients with seropositive active SLE. Patients were randomized to ustekinumab (approximately 6 mg/kg single intravenous infusion, then subcutaneous [SC] injections of 90 mg every 8 weeks) or placebo, added to background therapy. Placebo patients initiated ustekinumab (90 mg SC every 8 weeks) at week 24. Patients could enter an optional open-label study extension after week 40 (final ustekinumab administration at week 104). Efficacy assessments included Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K), SLEDAI-2K Responder Index-4 (SRI-4), physician global assessment (PGA), and Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI). Observed data are reported for the extension period. The final efficacy assessment was at week 112; safety was monitored through week 120. RESULTS: In this subset of patients who entered the study extension, 24 in the ustekinumab group and 14 in the placebo crossover group completed study treatment. At week 112, 79% and 92%, respectively, had an SRI-4 response; 92% in both groups had ≥ 4-point improvement from baseline in SLEDAI-2K score; 79% and 93%, respectively, had ≥ 30% improvement from baseline in PGA; 86% and 91%, respectively, had ≥ 50% improvement in active joint (pain and inflammation) count; and 79% and 100%, respectively, had ≥ 50% improvement in CLASI Activity Score. No deaths, malignancies, opportunistic infections, or tuberculosis cases occurred. Safety events were consistent with the known ustekinumab safety profile. CONCLUSION: Of the 46 patients who entered the voluntary extension of this phase II study, clinical benefit in global and organ-specific SLE activity measures was observed with ustekinumab through 2 years with no new or unexpected safety findings. [ClinicalTrials.gov: NCT02349061].

Targeted therapies in systemic lupus erythematosus: successes, failures and future.

PURPOSE: The author's goal is to review recent phase III clinical trials in patients with systemic lupus erythematosus (SLE), with emphasis on outcomes and on mechanisms by which the experimental drugs/biological agents suppress autoimmunity. METHODS: Prospective, randomised, controlled clinical trials in SLE published in the past 3 years identified in a PubMed search were reviewed, as well as abstracts describing similar but currently unpublished clinical trials presented at international meetings 2008-10. CONCLUSIONS: Two interventions have been proved in large multicentre prospective trials to be useful in the management of SLE: mycophenolate mofetil (equivalent to cyclophosphamide with a similar safety profile) and anti-BLyS (Benlysta), which was superior to placebo when added to background immunosuppression and did not appear to increase toxicity. The anti-BLyS trial outcome measure was an anchored composite index that required reduction of disease activity measure by the systemic lupus erythematosus disease activity index. Other trials that failed or the results of which are pending are also discussed.

High plasma leptin levels confer increased risk of atherosclerosis in women with systemic lupus erythematosus, and are associated with inflammatory oxidised lipids.

BACKGROUND: Patients with systemic lupus erythematosus (SLE) are at increased risk of atherosclerosis, even after accounting for traditional risk factors. High levels of leptin and low levels of adiponectin are associated with both atherosclerosis and immunomodulatory functions in the general population. OBJECTIVE: To examine the association between these adipokines and subclinical atherosclerosis in SLE, and also with other known inflammatory biomarkers of atherosclerosis. METHODS: Carotid ultrasonography was performed in 250 women with SLE and 122 controls. Plasma leptin and adiponectin levels were measured. Lipoprotein a (Lp(a)), oxidised phospholipids on apoB100 (OxPL/apoB100), paraoxonase, apoA-1 and inflammatory high-density lipoprotein (HDL) function were also assessed. RESULTS: Leptin levels were significantly higher in patients with SLE than in controls (23.7±28.0 vs 13.3±12.9 ng/ml, p<0.001). Leptin was also higher in the 43 patients with SLE with plaque than without plaque (36.4±32.3 vs 20.9±26.4 ng/ml, p=0.002). After multivariate analysis, the only significant factors associated with plaque in SLE were leptin levels in the highest quartile (≥29.5 ng/ml) (OR=2.8, p=0.03), proinflammatory HDL (piHDL) (OR=12.8, p<0.001), age (OR=1.1, p<0.001), tobacco use (OR=7.7, p=0.03) and hypertension (OR=3.0, p=0.01). Adiponectin levels were not significantly associated with plaque in our cohort. A significant correlation between leptin and piHDL function (p<0.001), Lp(a) (p=0.01) and OxPL/apoB100 (p=0.02) was also present. CONCLUSIONS: High leptin levels greatly increase the risk of subclinical atherosclerosis in SLE, and are also associated with an increase in inflammatory biomarkers of atherosclerosis such as piHDL, Lp(a) and OxPL/apoB100. High leptin levels may help to identify patients with SLE at risk of atherosclerosis.