Search tips
Search criteria

Results 1-14 (14)

Clipboard (0)

Select a Filter Below

more »
Year of Publication
Document Types
1.  Work disability, lost productivity and associated risk factors in patients diagnosed with systemic lupus erythematosus 
Lupus Science & Medicine  2015;2(1):e000058.
To assess prevalence and correlates of work presenteeism, absenteeism and work disability (WD) in patients with systemic lupus erythematous (SLE) and matched controls.
Patients with SLE from six medical centres were recruited to complete a questionnaire consisting of several prevalidated survey instruments. The subject's rheumatologist completed medical history. Subjects recruited two non-SLE ‘best friend’ controls with matching demographics to complete a control survey. Analyses employed Student's t tests, χ2 tests and logistic regression models.
344 subjects with SLE and 322 controls submitted completed questionnaires. Mean pain, fatigue, Brief Cognitive Symptoms Index (BCSI) scores and depressive symptoms were worse in patients with SLE with WD (all p<0.01). WD was associated with African–American race, older age (51–65 years) and less than 4-year college education (all p<0.01). High presenteeism was associated with low pain and fatigue levels, higher BCSI scores and negatively correlated with depressive symptoms (all p<0.05). Increased pain and fatigue were associated with elevated absenteeism (p<0.05). Subjects with physically and cognitively demanding work reported worse presenteeism compared with controls with similar jobs (77% vs 85%, p<0.05 and 75% vs 85%, p<0.001), respectively. Patients with most cognitively demanding jobs reported greater weekly absenteeism (mean, 5.9 h) compared with controls (mean, 6.9 overtime hours, p<0.05).
The questionnaire demonstrated increased WD in SLE. Highly physical and highly cognitive jobs are challenging to patients with SLE and had increased absenteeism compared with controls. Depressive symptoms were correlated with better presenteeism without major socio-demographic determinants. Employability may be enhanced by improving treatment of depressive symptoms in patients with SLE.
PMCID: PMC4305073  PMID: 25632349
Epidemiology; Systemic Lupus Erythematosus; Qualitative research
2.  Osteopontin Alleles Are Associated with Clinical Characteristics in Systemic Lupus Erythematosus 
Variants of the osteopontin (OPN) gene have been associated with systemic lupus erythematosus (SLE) susceptibility and cytokine profiles in SLE patients. It is not known whether these alleles are associated with specific clinical phenotypes in SLE. We studied 252 well-characterized SLE patients from a multiethnic cohort, genotyping the rs11730582, rs28357094, rs6532040, and rs9138 SNPs in the OPN gene. Ancestry informative markers were used to control for genetic ancestry. The SLE-risk allele rs9138C in the 3′ UTR region was associated with photosensitivity in lupus patients across all ancestral backgrounds (meta-analysis OR = 3.2, 95% CI = 1.6–6.5, P = 1.0 × 10−3). Additionally, the promoter variant rs11730582C demonstrated suggestive evidence for association with two hematologic traits: thrombocytopenia (OR = 2.1, P = 0.023) and hemolytic anemia (OR = 2.6, P = 0.036). These clinical associations with SNPs in the promoter and 3′ UTR regions align with previously reported SLE-susceptibility SNPs in OPN and suggest potential roles for these variants in antibody-mediated cytopenias and skin inflammation in SLE.
PMCID: PMC3205903  PMID: 22131818
3.  Cell Distance Mapping identifies functional T follicular helper cells in inflamed human renal tissue 
Science translational medicine  2014;6(230):230ra46.
T follicular helper (TFH) cells are critical for B cell activation in germinal centers and are often observed in human inflamed tissue. However, it is difficult to know if they contribute in situ to inflammation. Expressed markers define TFH subsets associated with distinct functions in vitro. However, such markers may not reflect in situ function. The delivery of T cell help to B cells requires direct cognate recognition. We hypothesized that by visualizing and quantifying such interactions we could directly assess TFH cell competency in situ. Therefore, we developed computational tools to quantify spatial relationships between different cell subtypes in tissue (Cell Distance Mapping, CDM). Analysis of inflamed human tissues indicated that measurement of internuclear distances between TFH and B cells could be used to discriminate between cognate and non-cognate interactions. Furthermore, only cognate-competent TFH cell populations expressed high levels of Bcl-6 and IL-21. These data suggest that CDM can be used to identify adaptive immune cell networks driving in situ inflammation. Such knowledge should help identify diseases, and disease subsets, that may benefit from therapeutics targeting of specific T cell:antigen presenting cell interactions.
PMCID: PMC4129446  PMID: 24695686
Lupus; nephritis; renal transplant; cell distance mapping; adaptive autoimmunity; T follicular helper cell
4.  The Autoimmune Disease Risk Allele of UBE2L3 in African American Patients with Systemic Lupus Erythematosus: A Recessive Effect Upon Subphenotypes 
The Journal of Rheumatology  2011;39(1):73-78.
UBE2L3 is associated with susceptibility to systemic lupus erythematosus (SLE) and rheumatoid arthritis in European ancestry populations, and this locus has not been investigated fully in non-European populations. We studied the UBE2L3 risk allele for association with SLE, interferon-α (IFN-α), and autoantibodies in a predominantly African American SLE cohort.
We studied 395 patients with SLE and 344 controls. The UBE2L3 rs5754217 polymorphism was genotyped using Taqman primer-probe sets, and IFN-α was measured using a reporter cell assay.
The UBE2L3 rs5754217 T allele was strongly enriched in African American patients with anti-La antibodies as compared to controls, and a recessive model was the best fit for this association (OR 2.55, p = 0.0061). Serum IFN-α also demonstrated a recessive association with the rs5754217 genotype in African American patients, and the TT/anti-La-positive patients formed a significantly high IFN-α subgroup (p = 0.0040). Similar nonstatistically significant patterns of association were observed in the European American patients with SLE. Case-control analysis did not show large allele frequency differences, supporting the idea that this allele is most strongly associated with anti-La-positive patients.
This pattern of recessive influence within a subgroup of patients may explain why this allele does not produce a strong signal in standard case-control studies, and subphenotypes should be included in future studies of UBE2L3. The interaction we observed between UBE2L3 genotype and autoantibodies upon serum IFN-α suggests a biological role for this locus in patients with SLE in vivo.
PMCID: PMC3304461  PMID: 22045845
5.  Autoimmune Disease Risk Variant of IFIH1 Is Associated with Increased Sensitivity to IFN-α and Serologic Autoimmunity in Lupus Patients 
Increased IFN-α signaling is a heritable risk factor for systemic lupus erythematosus (SLE). IFN induced with helicase C domain 1 (IFIH1) is a cytoplasmic dsRNA sensor that activates IFN-α pathway signaling. We studied the impact of the autoimmune-disease–associated IFIH1 rs1990760 (A946T) single nucleotide polymorphism upon IFN-α signaling in SLE patients in vivo. We studied 563 SLE patients (278 African-American, 179 European-American, and 106 Hispanic-American). Logistic regression models were used to detect genetic associations with autoantibody traits, and multiple linear regression was used to analyze IFN-α–induced gene expression in PBMCs in the context of serum IFN-α in the same blood sample. We found that the rs1990760 T allele was associated with anti-dsDNA Abs across all of the studied ancestral backgrounds (meta-analysis odds ratio = 1.34, p = 0.026). This allele also was associated with lower serum IFN-α levels in subjects who had anti-dsDNA Abs (p = 0.0026). When we studied simultaneous serum and PBMC samples from SLE patients, we found that the IFIH1 rs1990760 T allele was associated with increased IFN-induced gene expression in PBMCs in response to a given amount of serum IFN-α in anti-dsDNA–positive patients. This effect was independent of the STAT4 genotype, which modulates sensitivity to IFN-α in a similar way. Thus, the IFIH1 rs1990760 Tallele was associated with dsDNA Abs, and in patients with anti-dsDNA Abs this risk allele increased sensitivity to IFN-α signaling. These studies suggest a role for the IFIH1 risk allele in SLE in vivo.
PMCID: PMC3304466  PMID: 21705624
6.  Gene-Expression-Guided Selection of Candidate Loci and Molecular Phenotype Analyses Enhance Genetic Discovery in Systemic Lupus Erythematosus 
Systemic lupus erythematosus (SLE) is a highly heterogeneous autoimmune disorder characterized by differences in autoantibody profiles, serum cytokines, and clinical manifestations. We have previously conducted a case-case genome-wide association study (GWAS) of SLE patients to detect associations with autoantibody profile and serum interferon alpha (IFN-α). In this study, we used public gene expression data sets to rationally select additional single nucleotide polymorphisms (SNPs) for validation. The top 200 GWAS SNPs were searched in a database which compares genome-wide expression data to genome-wide SNP genotype data in HapMap cell lines. SNPs were chosen for validation if they were associated with differential expression of 15 or more genes at a significance of P < 9 × 10−5. This resulted in 11 SNPs which were genotyped in 453 SLE patients and 418 matched controls. Three SNPs were associated with SLE-associated autoantibodies, and one of these SNPs was also associated with serum IFN-α (P < 4.5 × 10−3 for all). One additional SNP was associated exclusively with serum IFN-α. Case-control analysis was insensitive to these molecular subphenotype associations. This study illustrates the use of gene expression data to rationally select candidate loci in autoimmune disease, and the utility of stratification by molecular phenotypes in the discovery of additional genetic associations in SLE.
PMCID: PMC3439981  PMID: 22988468
7.  Tubulointerstitial Inflammation and Scarring Predict Outcome in Lupus Nephritis 
Arthritis care & research  2011;63(6):865-874.
In lupus nephritis, glomerular injury correlates poorly with progression to renal failure. While the tubulointerstitium is also commonly involved, the importance of such involvement is not well defined. Therefore, we developed a simple method to assess the prognostic utility of measuring tubulointerstitial inflammation (TI).
Sixty-eight SLE patients with lupus nephritis were enrolled. Tubulointerstitial lymphocytic infiltrates were quantitated both by anti-CD45 antibody staining and standard histochemical staining. Follow-up data was obtained and survival analysis carried out to determine which histologic features were predictive of subsequent renal failure.
By CD45 staining TI was a common pathological finding, with 72% of biopsies having moderate or severe involvement. The extent of TI correlated with serum creatinine, but not with dsDNA antibodies, serum C3, or glomerular inflammation. TI severity, but not glomerular injury, identified patients at greater risk for renal failure (p=0.02). A high NIH chronicity index also identified patients at risk for renal failure. However, when the glomerular and tubulointerstitial subcomponents of the NIH chronicity index were separated in a bivariate model, only tubulointerstitial chronicity provided prognostic information (HR 2.2, 95% C.I. 1.3, 3.6, p=0.002 vs. HR 1.0, 95% C.I. 0.7, 1.5. p=0.97 for glomerular chronicity).
TI identifies lupus nephritis patients at greatest risk for progression to renal failure. The immunological mechanisms underlying TI may provide novel targets for therapeutic intervention.
PMCID: PMC3106120  PMID: 21309006
8.  A study of racial/ethnic differences in treatment preferences among lupus patients 
Rheumatology (Oxford, England)  2012;51(9):1697-1706.
Objectives. To determine whether there are racial/ethnic differences in the willingness of SLE patients to receive CYC or participate in clinical trials, and whether demographic, psychosocial and clinical characteristics contribute to these differences.
Methods. Data from 120 African-American and 62 white lupus patients were evaluated. Structured telephone interviews were conducted to determine treatment preferences, as well as to study characteristics and beliefs that may affect these preferences. Data were analysed using serial hierarchical multivariate logistic regression and deviances were calculated from a saturated model.
Results. Compared with their white counterparts, African-American SLE patients expressed less willingness to receive CYC (67.0% vs 84.9%, P = 0.02) if their lupus worsened. This racial/ethnic difference remained significant after adjusting for socioeconomic and psychosocial variables. Logistic regression analysis showed that African-American race [odds ratio (OR) 0.29, 95% CI 0.10, 0.80], physician trust (OR 1.05, 95% CI 1.00, 1.12) and perception of treatment effectiveness (OR 1.40, 95% CI 1.22, 1.61) were the most significant determinants of willingness to receive CYC. A trend in difference by race/ethnicity was also observed in willingness to participate in a clinical trial, but this difference was not significant.
Conclusion. This study demonstrated reduced likelihood of accepting CYC in African-American lupus patients compared with white lupus patients. This racial/ethnic variation was associated with belief in medication effectiveness and trust in the medical provider, suggesting that education about therapy and improved trust can influence decision-making among SLE patients.
PMCID: PMC3418647  PMID: 22653381
systemic lupus erythematosus; racial inequities; patient decision-making; patient preferences; cyclophosphamide
9.  Network Analysis of Associations between Serum Interferon Alpha Activity, Autoantibodies, and Clinical Features in Systemic Lupus Erythematosus 
Arthritis and rheumatism  2011;63(4):1044-1053.
Interferon-alpha (IFN-α) is a primary pathogenic factor in systemic lupus erythematosus (SLE), and high IFN-α levels may be associated with particular clinical manifestations. The prevalence of individual clinical and serologic features differs significantly by ancestry. We used multivariate and network analyses to detect associations between clinical and serologic disease manifestations and serum IFN-α activity in a large diverse SLE cohort.
1089 SLE patients were studied (387 African-American, 186 Hispanic-American, and 516 European-American). Presence or absence of ACR clinical criteria for SLE, autoantibodies, and serum IFN-α activity data were analyzed in univariate and multivariate models. Iterative multivariate logistic regression was performed in each background separately to establish the network of associations between variables that were independently significant following Bonferroni correction.
In all ancestral backgrounds, high IFN-α activity was associated with anti-Ro and anti-dsDNA antibodies (p-values 4.6×10−18 and 2.9 × 10−16 respectively). Younger age, non-European ancestry, and anti-RNP were also independently associated with increased serum IFN-α activity (p≤6.7×10−4). We found 14 unique associations between variables in network analysis, and only 7 of these associations were shared by more than one ancestral background. Associations between clinical criteria were different in different ancestral backgrounds, while autoantibody-IFN-α relationships were similar across backgrounds. IFN-α activity and autoantibodies were not associated with ACR clinical features in multivariate models.
Serum IFN-α activity was strongly and consistently associated with autoantibodies, and not independently associated with clinical features in SLE. IFN-α may be more relevant to humoral tolerance and initial pathogenesis than later clinical disease manifestations.
PMCID: PMC3068224  PMID: 21162028
systemic lupus erythematosus; interferon alpha; autoantibodies; ancestry
10.  The Lupus Family Registry and Repository 
Rheumatology (Oxford, England)  2010;50(1):47-59.
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.
PMCID: PMC3307518  PMID: 20864496
Systemic lupus erythematosus; Registry; Repository; Autoimmune diseases; Genetics; Heritability; Genome-wide association studies; Linkage analysis; Minorities; Women
11.  In situ B cell-mediated immune responses and tubulointerstitial inflammation in human lupus nephritis 
The most prevalent severe manifestation of systemic lupus erythematosus (SLE) is nephritis which is characterized by immune complex deposition, inflammation, and scarring in both glomeruli and in the tubulointerstitium. Numerous studies indicate that glomerulonephritis results from a systemic break in B cell tolerance resulting in the local deposition of immune complexes containing antibodies reactive with ubiquitous self-antigens. However, the pathogenesis of SLE tubulointerstitial disease is not known. Herein, we demonstrate that in over half of a cohort of 68 lupus nephritis biopsies, the tubulointerstitial infiltrate was organized into either well-circumscribed T:B cell aggregates or germinal centers (GCs) containing follicular dendritic cells. Sampling of the in situ expressed immunoglobulin repertoire revealed that both histological patterns were associated with intrarenal B cell clonal expansion and ongoing somatic hypermutation. However, in the GC histology the proliferating cells were CD138−CD20+ centroblasts while in T:B aggregates, they were CD138+CD20low/− plasmablasts. The presence of either GCs or T:B aggregates was strongly associated with tubular basement membrane immune complexes. These data implicate tertiary lymphoid neogenesis in the pathogenesis of lupus tubulointerstitial inflammation.
PMCID: PMC3124090  PMID: 21187439
B cells; somatic hypermutation; human; nephritis; systemic lupus erythematosus; tertiary lymphoid neogenesis; plasmablasts
12.  Genetic Variation at the IRF7/PHRF1 Locus Is Associated With Autoantibody Profile and Serum Interferon-α Activity in Lupus Patients 
Arthritis and rheumatism  2010;62(2):553-561.
Interferon-α (IFNα) is a heritable risk factor for systemic lupus erythematosus (SLE). Genetic variation near IRF7 is implicated in SLE susceptibility. SLE-associated autoantibodies can stimulate IFNα production through the Toll-like receptor/IRF7 pathway. This study was undertaken to determine whether variants of IRF7 act as risk factors for SLE by increasing IFNα production and whether autoantibodies are important to this phenomenon.
We studied 492 patients with SLE (236 African American, 162 European American, and 94 Hispanic American subjects). Serum levels of IFNα were measured using a reporter cell assay, and single-nucleotide polymorphisms (SNPs) in the IRF7/PHRF1 locus were genotyped.
In a joint analysis of European American and Hispanic American subjects, the rs702966 C allele was associated with the presence of anti–double-stranded DNA (anti-dsDNA) antibodies (odds ratio [OR] 1.83, P = 0.0069). The rs702966 CC genotype was only associated with higher serum levels of IFNα in European American and Hispanic American patients with anti-dsDNA antibodies (joint analysis P = 4.1 × 10−5 in anti-dsDNA–positive patients and P = 0.99 in anti-dsDNA–negative patients). In African American subjects, anti-Sm antibodies were associated with the rs4963128 SNP near IRF7 (OR 1.95, P = 0.0017). The rs4963128 CT and TT genotypes were associated with higher serum levels of IFNα only in African American patients with anti-Sm antibodies (P = 0.0012). In African American patients lacking anti-Sm antibodies, an effect of anti-dsDNA–rs702966 C allele interaction on serum levels of IFNα was observed, similar to the other patient groups (overall joint analysis P = 1.0 × 10−6). In European American and Hispanic American patients, the IRF5 SLE risk haplotype showed an additive effect with the rs702966 C allele on IFNα level in anti-dsDNA–positive patients.
Our findings indicate that IRF7/PHRF1 variants in combination with SLE-associated autoantibodies result in higher serum levels of IFNα, providing a biologic relevance for this locus at the protein level in human SLE in vivo.
PMCID: PMC2832192  PMID: 20112359
13.  Trait-stratified genome-wide association study identifies novel and diverse genetic associations with serologic and cytokine phenotypes in systemic lupus erythematosus 
Arthritis Research & Therapy  2010;12(4):R151.
Systemic lupus erythematosus (SLE) is a highly heterogeneous disorder, characterized by differences in autoantibody profile, serum cytokines, and clinical manifestations. SLE-associated autoantibodies and high serum interferon alpha (IFN-α) are important heritable phenotypes in SLE which are correlated with each other, and play a role in disease pathogenesis. These two heritable risk factors are shared between ancestral backgrounds. The aim of the study was to detect genetic factors associated with autoantibody profiles and serum IFN-α in SLE.
We undertook a case-case genome-wide association study of SLE patients stratified by ancestry and extremes of phenotype in serology and serum IFN-α. Single nucleotide polymorphisms (SNPs) in seven loci were selected for follow-up in a large independent cohort of 538 SLE patients and 522 controls using a multi-step screening approach based on novel metrics and expert database review. The seven loci were: leucine-rich repeat containing 20 (LRRC20); protein phosphatase 1 H (PPM1H); lysophosphatidic acid receptor 1 (LPAR1); ankyrin repeat and sterile alpha motif domain 1A (ANKS1A); protein tyrosine phosphatase, receptor type M (PTPRM); ephrin A5 (EFNA5); and V-set and immunoglobulin domain containing 2 (VSIG2).
SNPs in the LRRC20, PPM1H, LPAR1, ANKS1A, and VSIG2 loci each demonstrated strong association with a particular serologic profile (all odds ratios > 2.2 and P < 3.5 × 10-4). Each of these serologic profiles was associated with increased serum IFN-α. SNPs in both PTPRM and LRRC20 were associated with increased serum IFN-α independent of serologic profile (P = 2.2 × 10-6 and P = 2.6 × 10-3 respectively). None of the SNPs were strongly associated with SLE in case-control analysis, suggesting that the major impact of these variants will be upon subphenotypes in SLE.
This study demonstrates the power of using serologic and cytokine subphenotypes to elucidate genetic factors involved in complex autoimmune disease. The distinct associations observed emphasize the heterogeneity of molecular pathogenesis in SLE, and the need for stratification by subphenotypes in genetic studies. We hypothesize that these genetic variants play a role in disease manifestations and severity in SLE.
PMCID: PMC2945049  PMID: 20659327
14.  Promoter Variant of PIK3C3 Is Associated with Autoimmunity against Ro and Sm Epitopes in African-American Lupus Patients 
The PIK3C3 locus was implicated in case-case genome-wide association study of systemic lupus erythematosus (SLE) which we had performed to detect genes associated with autoantibodies and serum interferon-alpha (IFN-α). Herein, we examine a PIK3C3 promoter variant (rs3813065/-442 C/T) in an independent multiancestral cohort of 478 SLE cases and 522 controls. rs3813065 C was strongly associated with the simultaneous presence of both anti-Ro and anti-Sm antibodies in African-American patients [OR = 2.24 (1.34–3.73), P = 2.0 × 10−3]. This autoantibody profile was associated with higher serum IFN-α (P = 7.6 × 10−6). In the HapMap Yoruba population, rs3813065 was associated with differential expression of ERAP2 (P = 2.0 × 10−5), which encodes an enzyme involved in MHC class I peptide processing. Thus, rs3813065 C is associated with a particular autoantibody profile and altered expression of an MHC peptide processing enzyme, suggesting that this variant modulates serologic autoimmunity in African-American SLE patients.
PMCID: PMC2910508  PMID: 20671926

Results 1-14 (14)