Faculty Bibliography

OBJECTIVE: Vaccination against common pathogens, such as influenza, is recommended for patients with systemic lupus erythematosus (SLE) to decrease infections and improve health. However, most reports describing the vaccination response are limited to evaluations of SLE patients with quiescent disease. This study focuses on understanding the clinical, serologic, therapeutic, and demographic factors that influence the response to influenza vaccination in SLE patients with a broad range of disease activity. METHODS: Blood specimens and information on disease activity were collected from 72 patients with SLE, at baseline and at 2, 6, and 12 weeks after influenza vaccination. Influenza-specific antibody responses were assessed by determining the total serum antibody concentration (B(max)), relative affinity (K(a)), and level of hemagglutination inhibition in the plasma. Using a cumulative score, the patients were evenly divided into groups of high or low vaccine responders. Autoantibody levels were evaluated at each time point using immunofluorescence tests and standard enzyme-linked immunosorbent assays. RESULTS: Compared to high responders, low responders to the vaccine were more likely to have hematologic criteria (P = 0.009), to have more American College of Rheumatology classification criteria for SLE (P = 0.05), and to be receiving concurrent prednisone treatment (P = 0.04). Interestingly, European American patients were more likely to be low responders than were African American patients (P = 0.03). Following vaccination, low responders were more likely to experience disease flares (P = 0.01) and to have increased titers of antinuclear antibodies (P = 0.04). Serum interferon-alpha activity at baseline was significantly higher in patients in whom a flare occurred after vaccination compared to a matched group of patients who did not experience a disease flare (P = 0.04). CONCLUSION: Ancestral background, prednisone treatment, hematologic criteria, and evidence of increased likelihood of disease flares were associated with low antibody responses to influenza vaccination in SLE patients

OBJECTIVE: Genetic association of the IL2/IL21 region at chromosome 4q27 has previously been reported in lupus and a number of autoimmune and inflammatory diseases. This study was undertaken to determine whether this genetic effect could be localized, using a very large cohort of lupus patients and controls. METHODS: We genotyped 45 tag single-nucleotide polymorphisms (SNPs) across the IL2/IL21 locus in 2 large independent lupus sample sets. We studied a set of subjects of European descent consisting of 4,248 lupus patients and 3,818 healthy controls, and an African American set of 1,569 patients and 1,893 healthy controls. Imputation in 3,004 additional controls from the Wellcome Trust Case Control Consortium was also performed. Genetic association between the genotyped markers was determined, and pairwise conditional analysis was performed to localize the independent genetic effect in the IL2/IL21 locus in lupus. RESULTS: We established and confirmed the genetic association between IL2/IL21 and lupus. Using conditional analysis and transethnic mapping, we localized the genetic effect in this locus to 2 SNPs in high linkage disequilibrium: rs907715 located within IL21 (odds ratio 1.16 [95% confidence interval 1.10-1.22], P=2.17x10(-8)) and rs6835457 located in the 3'-untranslated flanking region of IL21 (odds ratio 1.11 [95% confidence interval 1.05-1.17], P=9.35x10(-5)). CONCLUSION: Our findings establish the genetic association between lupus and IL2/IL21 with a genome-wide level of significance. Further, our findings indicate that this genetic association within the IL2/IL21 linkage disequilibrium block is localized to IL21. If other autoimmune IL2/IL21 genetic associations are similarly localized, then the IL21 risk alleles would be predicted to operate by a fundamental mechanism that influences the course of a number of autoimmune disease processes

Systemic lupus erythematosus is a chronic-relapsing autoimmune disease of incompletely understood etiology. Recent evidence strongly supports an epigenetic contribution to the pathogenesis of lupus. To understand the extent and nature of dysregulated DNA methylation in lupus T cells, we performed a genome-wide DNA methylation study in CD4 (+) T cells in lupus patients compared to normal healthy controls. Cytosine methylation was quantified in 27,578 CG sites located within the promoter regions of 14,495 genes. We identified 236 hypomethylated and 105 hypermethylated CG sites in lupus CD4 (+) T cells compared to normal controls, consistent with widespread DNA methylation changes in lupus T cells. Of interest, hypomethylated genes in lupus T cells include CD9, which is known to provide potent T-cell co-stimulation signals. Other genes with known involvement in autoimmunity such as MMP9 and PDGFRA were also hypomethylated. The BST2 gene, an interferon-inducible membrane-bound protein that helps restrict the release of retroviral particles was also hypomethylated in lupus patients. Genes involved in folate biosynthesis, which plays a role in DNA methylation, were overrepresented among hypermethylated genes. In addition, the transcription factor RUNX3 was hypermethylated in patients, suggesting an impact on T-cell maturation. Protein-protein interaction maps identified a transcription factor, HNF4a, as a regulatory hub affecting a number of differentially methylated genes. Apoptosis was also an overrepresented ontology in these interaction maps. Further, our data suggest that the methylation status of RAB22A, STX1B2, LGALS3BP, DNASE1L1 and PREX1 correlates with disease activity in lupus patients

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) = 6.6x10(-8), OR = 1.18) and an intergenic SNP between CFHR1 and CFHR4 (rs16840639, P(meta) = 2.9x10(-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 (CFHR3-1Delta), 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 CFHR3-1Delta (P(meta) = 3.2x10(-7), OR = 1.47) conferred a higher risk of SLE than heterozygous deletion (P(meta) = 3.5x10(-4), OR = 1.14). These results suggested that the CFHR3-1Delta 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

Observations of familial aggregation (lambdas=8-29) and a 40% identical twin concordance rate prompted recent work towards a comprehensive genetic analysis of systemic lupus erythematosus (SLE). Since 2007, the number of genetic effects known to be associated with human lupus has increased by fivefold, underscoring the complexity of inheritance that probably contributes to this disease. Approximately 35 genes associated with lupus have either been replicated in multiple samples or are near the threshold for genome-wide significance (p > 5 x 10). Some are rare variants that convincingly contribute to lupus only in specific subgroups. Strong associations have been found with a large haplotype block in the human leucocyte antigen region, with Fcgamma receptors, and with genes coding for complement components, in which a single gene deletion may cause SLE in rare familial cases and copy number variation is more common in the larger population of SLE patients. Examples of newly discovered genes include ITGAM, STAT4 and MECP2/IRAK1. Ongoing studies to build models in which combinations of associated genes might contribute to specific disease manifestations should contribute to improved understanding of disease pathology. In addition, pharmacogenomic components of ongoing clinical trials are likely to provide insights into fundamental disease pathology as well as contributing to informed patient selection for targeted treatments and biomarkers to guide dosing and gauge responsiveness. Besides these potentially valuable new insights into the pathophysiology of an enigmatic, potentially deadly, and, as yet, unsolved disease, genetic studies are likely to suggest novel molecular targets for strategic development of safer and more effective therapeutics

The Lupus Family Registry and Repository (LFRR) was established with the goal of assembling and distributing materials and data from families with one or more living members diagnosed with SLE, in order to address SLE genetics. In the present article, we describe the problems and solutions of the registry design and biometric data gathering; the protocols implemented to guarantee data quality and protection of participant privacy and consent; and the establishment of a local and international network of collaborators. At the same time, we illustrate how the LFRR has enabled progress in lupus genetics research, answering old scientific questions while laying out new challenges in the elucidation of the biologic mechanisms that underlie disease pathogenesis. Trained staff ascertain SLE cases, unaffected family members and population-based controls, proceeding in compliance with the relevant laws and standards; participant consent and privacy are central to the LFRR's effort. Data, DNA, serum, plasma, peripheral blood and transformed B-cell lines are collected and stored, and subject to strict quality control and safety measures. Coded data and materials derived from the registry are available for approved scientific users. The LFRR has contributed to the discovery of most of the 37 genetic associations now known to contribute to lupus through 104 publications. The LFRR contains 2618 lupus cases from 1954 pedigrees that are being studied by 76 approved users and their collaborators. The registry includes difficult to obtain populations, such as multiplex pedigrees, minority patients and affected males, and constitutes the largest collection of lupus pedigrees in the world. The LFRR is a useful resource for the discovery and characterization of genetic associations in SLE

OBJECTIVE:To describe vascular events during an 8-year followup in a multicenter systemic lupus erythematosus (SLE) inception cohort and their attribution to atherosclerosis. METHODS:Clinical data, including comorbidities, were recorded yearly. Vascular events were recorded and attributed to atherosclerosis or not. All of the events met standard clinical criteria. Factors associated with atherosclerotic vascular events were analyzed using descriptive statistics, t-tests, and chi-square tests. Stepwise multivariate logistic regression was used to assess the association of factors with vascular events attributed to atherosclerosis. RESULTS:Since 2000, 1,249 patients have been entered into the cohort. There have been 97 vascular events in 72 patients, including: myocardial infarction (n = 13), angina (n = 15), congestive heart failure (n = 24), peripheral vascular disease (n = 8), transient ischemic attack (n = 13), stroke (n = 23), and pacemaker insertion (n = 1). Fifty of the events were attributed to active lupus, 31 events in 22 patients were attributed to atherosclerosis, and 16 events were attributed to other causes. The mean +/- SD time from diagnosis to the first atherosclerotic event was 2.0 +/- 1.5 years. Compared with patients followed for 2 years without atherosclerotic events (n = 615), at enrollment, patients with atherosclerotic vascular events were more frequently white, men, older at diagnosis of SLE, obese, smokers, hypertensive, and had a family history of coronary artery disease. On multivariate analysis, only male sex and older age at diagnosis were associated factors. CONCLUSION/CONCLUSIONS:In an inception cohort with SLE followed for up to 8 years, there were 97 vascular events, but only 31 were attributable to atherosclerosis. Patients with atherosclerotic events were more likely to be men and to be older at diagnosis of SLE.

Objectives: SLE patients (pts) with moderate-to-severe disease activity (>=1 BILAG A or >=2 BILAG B domain scores) despite background immunosuppressives and corticosteroids, were randomized to placebo (PLA) or rituximab (RTX). Although differences in primary and secondary outcome measures were not observed, an exploratory analysis was performed to evaluate the imObjectives: SLE patients (pts) with moderate-to-severe disease activity (>=1 BILAG A or >=2 BILAG B domain scores) despite background immunosuppressives and corticosteroids, were randomized to placebo (PLA) or rituximab (RTX). Although differences in primary and secondary outcome measures were not observed, an exploratory analysis was performed to evaluate the impact of RTX on disease flares. Our objectives were to assess in those pts who achieved response whether RTX affected: 1) time to moderate or severe flares, 2) annualized flare rates, and 3) prednisone usage during flares. Methods: Pts who achieved response (BILAG C, D, E scores for all domains before wk52) on monthly BILAG assessments were included in this analysis. Flares, defined as increased disease activity following achievement of response, were stratified as follows: Severe flare: >=1 BILAG A or >3 BILAG B domain scores; A flare: >=1 new BILAG A domain scores; Moderate flare: 2 BILAG B domain scores. Kaplan-Meier estimates were used to assess time-to-flare. Annualized flare rates were calculated using number of flares per patient with a Poisson regression model. Only flares that occurred after the protocol-mandated prednisone taper at 12 wks were included in the analysis of prednisone use during flares. Results: Responses were achieved in 58/88 (66.0%) PLA-treated and 127/169 (75.1%) RTX-treated pts during the study. No difference was found between rituximab and placebo in preventing or delaying moderate to severe flares. However, when BILAG A flares alone were examined, rituximab reduced the risk of an A flare after achieving a response by 52 weeks (hazard ratio=0.612; p=0.0524) and lowered the annualized A flare rate (0.86 +/- 1.47 (SD) vs 1.41 +/- 2.14; p=.038). Eighty-four of 169 (49.7%) rituximab-treated patients achieved low disease activity without subsequent A flares versus 31/88 (35.2%) patients in the placebo group (p=0.027). Prednisone rescue for A flares was similar in rituximab- (24%) and placebo-treated (14%) patients (p=.204). Conclusions: No conclusions about rituximab efficacy can be drawn from this post hoc analysis. This exploratory analysis suggests that assessment of BILAG A flares may distinguish potential treatment effects with more sensitivity than BILAG B flares, which capture modest changes in disease activity. If confirmed in other studies, this observation may help in the design of more robust clinical trial protocols