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1.
bioRxiv ; 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-35547855

ABSTRACT

Clinical diagnosis typically incorporates physical examination, patient history, and various laboratory tests and imaging studies, but makes limited use of the human system's own record of antigen exposures encoded by receptors on B cells and T cells. We analyzed immune receptor datasets from 593 individuals to develop MAchine Learning for Immunological Diagnosis (Mal-ID) , an interpretive framework to screen for multiple illnesses simultaneously or precisely test for one condition. This approach detects specific infections, autoimmune disorders, vaccine responses, and disease severity differences. Human-interpretable features of the model recapitulate known immune responses to SARS-CoV-2, Influenza, and HIV, highlight antigen-specific receptors, and reveal distinct characteristics of Systemic Lupus Erythematosus and Type-1 Diabetes autoreactivity. This analysis framework has broad potential for scientific and clinical interpretation of human immune responses.

2.
JCI Insight ; 8(16)2023 08 22.
Article in English | MEDLINE | ID: mdl-37606045

ABSTRACT

Systemic lupus erythematosus (SLE) affects 1 in 537 Black women, which is >2-fold more than White women. Black patients develop the disease at a younger age, have more severe symptoms, and have a greater chance of early mortality. We used a multiomics approach to uncover ancestry-associated immune alterations in patients with SLE and healthy controls that may contribute biologically to disease disparities. Cell composition, signaling, epigenetics, and proteomics were evaluated by mass cytometry; droplet-based single-cell transcriptomics and proteomics; and bead-based multiplex soluble mediator levels in plasma. We observed altered whole blood frequencies and enhanced activity in CD8+ T cells, B cells, monocytes, and DCs in Black patients with more active disease. Epigenetic modifications in CD8+ T cells (H3K27ac) could distinguish disease activity level in Black patients and differentiate Black from White patient samples. TLR3/4/7/8/9-related gene expression was elevated in immune cells from Black patients with SLE, and TLR7/8/9 and IFN-α phospho-signaling and cytokine responses were heightened even in immune cells from healthy Black control patients compared with White individuals. TLR stimulation of healthy immune cells recapitulated the ancestry-associated SLE immunophenotypes. This multiomic resource defines ancestry-associated immune phenotypes that differ between Black and White patients with SLE, which may influence the course and severity of SLE and other diseases.


Subject(s)
B-Lymphocytes , Lupus Erythematosus, Systemic , Female , Humans , Black People , CD8-Positive T-Lymphocytes , Lupus Erythematosus, Systemic/genetics , Phenotype , White People
3.
Ann Rheum Dis ; 82(5): 670-680, 2023 05.
Article in English | MEDLINE | ID: mdl-36653124

ABSTRACT

OBJECTIVES: Results from the SCOT (Scleroderma: Cyclophosphamide Or Transplantation) clinical trial demonstrated significant benefits of haematopoietic stem cell transplant (HSCT) versus cyclophosphamide (CTX) in patients with systemic sclerosis. The objective of this study was to test the hypothesis that transplantation stabilises the autoantibody repertoire in patients with favourable clinical outcomes. METHODS: We used a bead-based array containing 221 protein antigens to profile serum IgG autoantibodies in participants of the SCOT trial. RESULTS: Comparison of autoantibody profiles at month 26 (n=23 HSCT; n=22 CTX) revealed antibodies against two viral antigens and six self-proteins (SSB/La, CX3CL1, glycyl-tRNA synthetase (EJ), parietal cell antigen, bactericidal permeability-increasing protein and epidermal growth factor receptor (EGFR)) that were significantly different between treatment groups. Linear mixed model analysis identified temporal increases in antibody levels for hepatitis B surface antigen, CCL3 and EGFR in HSCT-treated patients. Eight of 32 HSCT-treated participants and one of 31 CTX-treated participants had temporally varying serum antibody profiles for one or more of 14 antigens. Baseline autoantibody levels against 20 unique antigens, including 9 secreted proteins (interleukins, IL-18, IL-22, IL-23 and IL-27), interferon-α2A, stem cell factor, transforming growth factor-ß, macrophage colony-stimulating factor and macrophage migration inhibitory factor were significantly higher in patients who survived event-free to month 54. CONCLUSIONS: Our results suggest that HSCT favourably alters the autoantibody repertoire, which remains virtually unchanged in CTX-treated patients. Although antibodies recognising secreted proteins are generally thought to be pathogenic, our results suggest a subset could potentially modulate HSCT in scleroderma.


Subject(s)
Hematopoietic Stem Cell Transplantation , Scleroderma, Systemic , Humans , Autoantibodies , Scleroderma, Systemic/pathology , Hematopoietic Stem Cell Transplantation/methods , Cyclophosphamide/therapeutic use , Transplantation, Autologous
4.
Lupus Sci Med ; 10(1)2023 01.
Article in English | MEDLINE | ID: mdl-36599633

ABSTRACT

OBJECTIVE: Patients with incomplete lupus erythematosus (ILE) have lupus features but insufficient criteria for SLE classification. Some patients with ILE transition to SLE, but most avoid major organ involvement. This study tested whether the milder disease course in ILE is influenced by reduced SLE risk allele genetic load. METHODS: We calculated the genetic load based on 99 SLE-associated risk alleles in European American patients with SLE (≥4 American College of Rheumatology (ACR) 1997 criteria, n=170), patients with ILE (3 ACR 1997 criteria, n=169), a subset of patients with ILE not meeting Systemic Lupus International Collaborating Clinics (SLICC) classification (ILESLICC, n=119) and healthy controls (n=133). Unweighted genetic loads were calculated as the total sum of risk alleles for each individual, while weighted genetic loads were defined as the sum of risk alleles multiplied by the natural logarithm of the previously published OR of each risk allele for SLE susceptibility. RESULTS: The median unweighted and weighted SLE risk allele genetic load was significantly greater in patients with ILE (unweighted: 81, p value=0.01; weighted: 16.3, p value=0.001) and patients with SLE (80, p value=0.02; 16.29, p value=0.0006) compared with healthy controls (78, 15.76). Patients with ILESLICC trended towards an increased genetic load, although not statistically significant (unweighted: 80, p value=0.14; weighted: 16.05, p value=0.07). However, the median genetic load did not significantly differ between ILE and SLE, and genetic load did not differentiate patients with ILE and SLE (area under the curve=0.51, p=0.78) by receiver operator characteristic analysis. CONCLUSIONS: Patients with ILE and SLE have comparable genetic loads of SLE risk loci, suggesting similar genetic predispositions between these conditions. Phenotypical differences between SLE and ILE may instead be influenced by ILE-specific variants and gene-environment interactions.


Subject(s)
Lupus Erythematosus, Systemic , Rheumatology , Humans , United States , Lupus Erythematosus, Systemic/genetics , Genetic Load , Severity of Illness Index , Disease Progression
5.
Arthritis Rheumatol ; 75(5): 723-735, 2023 05.
Article in English | MEDLINE | ID: mdl-36245261

ABSTRACT

OBJECTIVE: Systemic lupus erythematosus (SLE) is marked by immune dysregulation linked to varied clinical disease activity. Using a unique longitudinal cohort of SLE patients, this study sought to identify optimal immune mediators informing an empirically refined flare risk index (FRI) reflecting altered immunity prior to clinical disease flare. METHODS: Thirty-seven SLE-associated plasma mediators were evaluated by microfluidic immunoassay in 46 samples obtained in SLE patients with an imminent clinical disease flare (preflare) and 53 samples obtained in SLE patients without a flare over a corresponding period (pre-nonflare). SLE patients were selected from a unique longitudinal cohort of 106 patients with classified SLE (meeting the American College of Rheumatology 1997 revised criteria for SLE or the Systemic Lupus International Collaborating Clinics 2012 revised criteria for SLE). Autoantibody specificities, hybrid SLE Disease Activity Index (hSLEDAI) scores, clinical features, and medication usage were also compared at preflare (mean ± SD 111 ± 47 days prior to flare) versus pre-nonflare (99 ± 21 days prior to nonflare) time points. Variable importance was determined by random forest analysis with logistic regression subsequently applied to determine the optimal number and type of analytes informing a refined FRI. RESULTS: Preflare versus pre-nonflare differences were not associated with demographics, autoantibody specificities, hSLEDAI scores, clinical features, nor medication usage. Forward selection and backward elimination of mediators ranked by variable importance resulted in 17 plasma mediator candidates differentiating preflare from pre-nonflare visits. A final combination of 11 mediators best informed a newly refined FRI, which achieved a maximum sensitivity of 97% and maximum specificity of 98% after applying decision curve analysis to define low, medium, and high FRI scores. CONCLUSION: We verified altered immune mediators associated with imminent disease flare, and a subset of these mediators improved the FRI to identify SLE patients at risk of imminent flare. This molecularly informed, proactive management approach could be critical in prospective clinical trials and the clinical management of lupus.


Subject(s)
Immunologic Factors , Lupus Erythematosus, Systemic , Humans , Prospective Studies , Symptom Flare Up , Immunologic Factors/therapeutic use , Autoantibodies , Severity of Illness Index
6.
Mult Scler Relat Disord ; 63: 103922, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35671674

ABSTRACT

BACKGROUND: For relapsing-remitting multiple sclerosis (RRMS), there is a need for biomarker development beyond clinical manifestations and MRI. Soluble neurofilament light chain (sNfL) has emerged as a biomarker for inflammatory activity in RRMS. However, there are limitations to the accuracy of sNfL in identifying relapses. Here, we sought to identify a panel of biomarkers that would increase the precision of distinguishing patients in relapse compared to sNfL alone. METHODS: We used a multiplex approach to measure levels of 724 blood proteins in two distinct RRMS cohorts. Multiple t-tests with covariate correction determined biomarkers that were differentially regulated in relapse and remission. Logistic regression models determined the accuracy of biomarkers to distinguish relapses from remission. RESULTS: The discovery cohort identified 37 proteins differentially abundant in active RRMS relapse compared to remission. The verification cohort confirmed four proteins, including sNfL, were altered in active RRMS relapse compared to remission. Logistic regression showed that the 4-protein panel identified active relapse with higher accuracy (AUC = 0.87) than sNfL alone (AUC = 0.69). CONCLUSION: Our studies confirmed that sNfL is elevated during relapses in RRMS patients. Furthermore, we identified three other blood proteins, uPA, hK8 and DSG3 that were altered during relapse. Together, these four biomarkers could be used to monitor disease activity in RRMS patients.


Subject(s)
Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , Biomarkers , Chronic Disease , Humans , Multiple Sclerosis/diagnostic imaging , Multiple Sclerosis, Relapsing-Remitting/diagnostic imaging , Recurrence
7.
Front Immunol ; 13: 881332, 2022.
Article in English | MEDLINE | ID: mdl-35720397

ABSTRACT

Objective: Higher 25-hydroxyvitamin D (25(OH)D) levels have been associated with reduced risk for autoimmune diseases and are influenced by vitamin D metabolism genes. We estimated genetically-determined vitamin D levels by calculating a genetic risk score (GRS) and investigated whether the vitamin D GRS was associated with the presence of autoantibodies related to rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) in those at increased risk for developing RA and SLE, respectively. Methods: In this cross-sectional study, we selected autoantibody positive (aAb+) and autoantibody negative (aAb-) individuals from the Studies of the Etiologies of Rheumatoid Arthritis (SERA), a cohort study of first-degree relatives (FDRs) of individuals with RA (189 RA aAb+, 181 RA aAb-), and the Lupus Family Registry and Repository (LFRR), a cohort study of FDRs of individuals with SLE (157 SLE aAb+, 185 SLE aAb-). Five SNPs known to be associated with serum 25(OH)D levels were analyzed individually as well as in a GRS: rs4588 (GC), rs12785878 (NADSYN1), rs10741657 (CYP2R1), rs6538691 (AMDHD1), and rs8018720 (SEC23A). Results: Both cohorts had similar demographic characteristics, with significantly older and a higher proportion of males in the aAb+ FDRs. The vitamin D GRS was inversely associated with RA aAb+ (OR = 0.85, 95% CI = 0.74-0.99), suggesting a possible protective factor for RA aAb positivity in FDRs of RA probands. The vitamin D GRS was not associated with SLE aAb+ in the LFRR (OR = 1.09, 95% CI = 0.94-1.27). The SEC23A SNP was associated with RA aAb+ in SERA (OR = 0.65, 95% CI = 0.43-0.99); this SNP was not associated with SLE aAb+ in LFRR (OR = 1.41, 95% CI = 0.90 - 2.19). Conclusion: Genes associated with vitamin D levels may play a protective role in the development of RA aAbs in FDRs of RA probands, perhaps through affecting lifelong vitamin D status. The GRS and the SEC23A SNP may be of interest for future investigation in pre-clinical RA. In contrast, these results do not support a similar association in SLE FDRs, suggesting other mechanisms involved in the relationship between vitamin D and SLE aAbs not assessed in this study.


Subject(s)
Arthritis, Rheumatoid , Lupus Erythematosus, Systemic , Arthritis, Rheumatoid/epidemiology , Arthritis, Rheumatoid/genetics , Autoantibodies , Cohort Studies , Cross-Sectional Studies , Humans , Lupus Erythematosus, Systemic/epidemiology , Lupus Erythematosus, Systemic/genetics , Male , Risk Factors , Vitamin D , Vitamins
8.
J Transl Autoimmun ; 4: 100117, 2021.
Article in English | MEDLINE | ID: mdl-35005588

ABSTRACT

SLE is a clinically heterogeneous disease characterized by an unpredictable relapsing-remitting disease course. Although the etiology and mechanisms of SLE flares remain elusive, Epstein-Barr virus (EBV) reactivation is implicated in SLE pathogenesis. This study examined the relationships between serological measures of EBV reactivation, disease activity, and interferon (IFN)-associated immune pathways in SLE patients. Sera from adult SLE patients (n = 175) and matched unaffected controls (n = 47) were collected and tested for antibodies against EBV-viral capsid antigen (EBV-VCA; IgG and IgA), EBV-early antigen (EBV-EA; IgG), cytomegalovirus (CMV; IgG), and herpes simplex virus (HSV-1; IgG). Serological evidence of EBV reactivation was more common in SLE patients compared to controls as demonstrated by seropositivity to EBV-EA IgG (39% vs 13%; p = 0.0011) and EBV-VCA IgA (37% vs 17%; p = 0.018). EBV-VCA, CMV1, and HSV-1 IgG seropositivity rates did not differ between SLE patients and controls. Furthermore, concentrations of EBV-VCA (IgG and IgA) and EBV-EA (IgG) were higher in SLE patients. SLE patients with high disease activity had increased concentrations of EBV-VCA IgA (mean ISR 1.34 vs. 0.97; p = 0.041) and EBV-EA IgG levels (mean ISR 1.38 vs. 0.90; p = 0.007) compared with those with lower disease activity. EBV reactivation was associated with enhanced levels of the IFN-associated molecule IP-10 (p < 0.001) and the soluble mediators BLyS (p < 0.001) and IL-10 (p = 0.0011). In addition, EBV-EA IgG responses were enriched in two previously defined patient clusters with robust expression of IFN and inflammatory or lymphoid and monocyte responses. Patients in these clusters were also more likely to have major organ involvement, such as renal disease. This study supports a possible role for EBV reactivation in SLE disease activity.

9.
J Clin Med ; 9(7)2020 Jul 08.
Article in English | MEDLINE | ID: mdl-32650575

ABSTRACT

To assess the types of salivary gland (SG) T cells contributing to Sjögren's syndrome (SS), we evaluated SG T cell subtypes for association with disease features and compared the SG CD4+ memory T cell transcriptomes of subjects with either primary SS (pSS) or non-SS sicca (nSS). SG biopsies were evaluated for proportions and absolute numbers of CD4+ and CD8+ T cells. SG memory CD4+ T cells were evaluated for gene expression by microarray. Differentially-expressed genes were identified, and gene set enrichment and pathways analyses were performed. CD4+CD45RA- T cells were increased in pSS compared to nSS subjects (33.2% vs. 22.2%, p < 0.0001), while CD8+CD45RA- T cells were decreased (38.5% vs. 46.0%, p = 0.0014). SG fibrosis positively correlated with numbers of memory T cells. Proportions of SG CD4+CD45RA- T cells correlated with focus score (r = 0.43, p < 0.0001), corneal damage (r = 0.43, p < 0.0001), and serum Ro antibodies (r = 0.40, p < 0.0001). Differentially-expressed genes in CD4+CD45RA- cells indicated a T follicular helper (Tfh) profile, increased homing and increased cellular interactions. Predicted upstream drivers of the Tfh signature included TCR, TNF, TGF-ß1, IL-4, and IL-21. In conclusion, the proportions and numbers of SG memory CD4+ T cells associate with key SS features, consistent with a central role in disease pathogenesis.

10.
J Allergy Clin Immunol ; 146(6): 1419-1433, 2020 12.
Article in English | MEDLINE | ID: mdl-32446964

ABSTRACT

BACKGROUND: Autoimmune diseases comprise a spectrum of illnesses and are on the rise worldwide. Although antinuclear antibodies (ANAs) are detected in many autoimmune diseases, up to 20% of healthy women are ANA-positive (ANA+) and most will never develop clinical symptoms. Furthermore, disease transition is higher among ANA+ African Americans compared with ANA+ European Americans. OBJECTIVE: We sought to determine the immune features that might define and prevent transition to clinical autoimmunity in ANA+ healthy individuals. METHODS: We comprehensively phenotyped immune profiles of African Americans and European Americans who are ANA-negative (ANA-) healthy, ANA+ healthy, or have SLE using single cell mass cytometry, next-generation RNA-sequencing, multiplex cytokine profiling, and phospho-signaling analyses. RESULTS: We found that, compared with both ANA- and ANA+ healthy individuals, patients with SLE of both races displayed T-cell expansion and elevated expression of type I and II interferon pathways. We discovered a unique immune signature that suggests a suppressive immune phenotype and reduced CD11C+ autoimmunity-associated B cells in healthy ANA+ European Americans that is absent in their SLE or even healthy ANA- counterparts, or among African American cohorts. In contrast, ANA+ healthy African Americans exhibited elevated expression of T-cell activation markers and higher plasma levels of IL-6 than did healthy ANA+ European Americans. CONCLUSIONS: We propose that this novel immune signature identified in ANA+ healthy European Americans may protect them from T-cell expansion, heightened activation of interferon pathways, and disease transition.


Subject(s)
Antibodies, Antinuclear/immunology , Black or African American , Lupus Erythematosus, Systemic/immunology , Lymphocyte Activation , Signal Transduction/immunology , T-Lymphocytes/immunology , White People , Adult , Female , Humans , Lupus Erythematosus, Systemic/pathology , Male , T-Lymphocytes/pathology
11.
EClinicalMedicine ; 20: 100291, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32154507

ABSTRACT

BACKGROUND: The clinical and pathologic diversity of systemic lupus erythematosus (SLE) hinders diagnosis, management, and treatment development. This study addresses heterogeneity in SLE through comprehensive molecular phenotyping and machine learning clustering. METHODS: Adult SLE patients (n = 198) provided plasma, serum, and RNA. Disease activity was scored by modified SELENA-SLEDAI. Twenty-nine co-expression module scores were calculated from microarray gene-expression data. Plasma soluble mediators (n = 23) and autoantibodies (n = 13) were assessed by multiplex bead-based assays and ELISAs. Patient clusters were identified by machine learning combining K-means clustering and random forest analysis of co-expression module scores and soluble mediators. FINDINGS: SLEDAI scores correlated with interferon, plasma cell, and select cell cycle modules, and with circulating IFN-α, IP10, and IL-1α levels. Co-expression modules and soluble mediators differentiated seven clusters of SLE patients with unique molecular phenotypes. Inflammation and interferon modules were elevated in Clusters 1 (moderately) and 4 (strongly), with decreased T cell modules in Cluster 4. Monocyte, neutrophil, plasmablast, B cell, and T cell modules distinguished the remaining clusters. Active clinical features were similar across clusters. Clinical SLEDAI trended highest in Clusters 3 and 4, though Cluster 3 lacked strong interferon and inflammation signatures. Renal activity was more frequent in Cluster 4, and rare in Clusters 2, 5, and 7. Serology findings were lowest in Clusters 2 and 5. Musculoskeletal and mucocutaneous activity were common in all clusters. INTERPRETATION: Molecular profiles distinguish SLE subsets that are not apparent from clinical information. Prospective longitudinal studies of these profiles may help improve prognostic evaluation, clinical trial design, and precision medicine approaches. FUNDING: US National Institutes of Health.

12.
Sci Rep ; 9(1): 17514, 2019 Nov 20.
Article in English | MEDLINE | ID: mdl-31745194

ABSTRACT

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

13.
Sci Rep ; 9(1): 8590, 2019 06 13.
Article in English | MEDLINE | ID: mdl-31197240

ABSTRACT

Systemic lupus erythematosus (SLE) flares elicit progressive organ damage, leading to disability and early mortality. This study evaluated clinical and immunologic factors associated with impending flare in the Biomarkers of Lupus Disease study. Autoantibodies and 32 soluble mediators were measured by multiplex assays, immune pathway activation by gene expression module scores, and immune cell subset frequencies and activation states by flow cytometry. After providing baseline samples, participants received transient steroids to suppress disease and were followed until flare. Flare occurred early (within 60 days of baseline) in 21 participants and late (90-165 days) in 13. At baseline, compared to the late flare group, the early flare group had differential gene expression in monocyte, T cell, interferon, and inflammation modules, as well as significantly higher frequencies of activated (aCD11b+) neutrophils and monocytes, and activated (CD86hi) naïve B cells. Random forest models showed three subgroups of early flare patients, distinguished by greater baseline frequencies of aCD11b+ monocytes, or CD86hi naïve B cells, or both. Increases in these cell populations were the most accurate biomarkers for early flare in this study. These results suggest that SLE flares may arise from an overlapping spectrum of lymphoid and myeloid mechanisms in different patients.


Subject(s)
Lupus Erythematosus, Systemic/drug therapy , Lupus Erythematosus, Systemic/immunology , Steroids/therapeutic use , Adult , B-Lymphocytes/immunology , Cell Differentiation , Cohort Studies , Female , Humans , Interferon-gamma/blood , Lupus Erythematosus, Systemic/blood , Lupus Erythematosus, Systemic/genetics , Lymphocyte Activation/immunology , Male , Middle Aged , Models, Biological , Monocytes/immunology , Neutrophils/immunology , Receptors, Tumor Necrosis Factor/blood , Transcription, Genetic , Young Adult
14.
JCI Insight ; 4(2)2019 Jan 24.
Article in English | MEDLINE | ID: mdl-30674728

ABSTRACT

Systemic lupus erythematosus (SLE) is a highly variable autoimmune disease that can involve severe organ-threatening symptoms, such as lupus nephritis. Certain drugs, such as mycophenolate mofetil (MMF), are effective at reducing morbidity associated with nephritis; however, the immune pathways associated with disease suppression are poorly defined. Here, we provide evidence that MMF inhibits phosphorylation of STAT3 and other associated immune pathways. Using mass cytometry and bead-based or ELISA assays, the systemic phenotype of SLE patients not taking (MMF-) or taking (MMF+) MMF were studied. MMF+ SLE patients had significant reductions in total numbers of transitional B cells, plasmablasts, and T cells, specifically CD4+ Th17-type and CD4+ Treg-type cells, compared with MMF- patients. Plasma soluble mediators were decreased in MMF+ patients including chemokines (MIG/CXCL9 and SDF-1α/CXCL12) and growth factors (VEGF-A and PDGF-BB). Soluble mediators and cell subsets grouped by functional properties revealed significant modifications associated with STAT3 and B cell pathways. Further, healthy PBMCs treated with IL-6 revealed a reduction in p-STAT3 following the addition of mycophenolic acid (the active metabolite of MMF). In conclusion, the inhibition of STAT3 phosphorylation by MMF may explain the effectiveness of this treatment in SLE patients, since increased levels of p-STAT3 are associated with disease pathology.

15.
JCI Insight ; 3(14)2018 07 26.
Article in English | MEDLINE | ID: mdl-30046013

ABSTRACT

Site-1 protease (S1P), encoded by MBTPS1, is a serine protease in the Golgi. S1P regulates lipogenesis, endoplasmic reticulum (ER) function, and lysosome biogenesis in mice and in cultured cells. However, how S1P differentially regulates these diverse functions in humans has been unclear. In addition, no human disease with S1P deficiency has been identified. Here, we report a pediatric patient with an amorphic and a severely hypomorphic mutation in MBTPS1. The unique combination of these mutations results in a frequency of functional MBTPS1 transcripts of approximately 1%, a finding that is associated with skeletal dysplasia and elevated blood lysosomal enzymes. We found that the residually expressed S1P is sufficient for lipid homeostasis but not for ER and lysosomal functions, especially in chondrocytes. The defective S1P function specifically impairs activation of the ER stress transducer BBF2H7, leading to ER retention of collagen in chondrocytes. S1P deficiency also causes abnormal secretion of lysosomal enzymes due to partial impairment of mannose-6-phosphate-dependent delivery to lysosomes. Collectively, these abnormalities lead to apoptosis of chondrocytes and lysosomal enzyme-mediated degradation of the bone matrix. Correction of an MBTPS1 variant or reduction of ER stress mitigated collagen-trafficking defects. These results define a new congenital human skeletal disorder and, more importantly, reveal that S1P is particularly required for skeletal development in humans. Our findings may also lead to new therapies for other genetic skeletal diseases, as ER dysfunction is common in these disorders.


Subject(s)
Bone Diseases, Developmental/genetics , Bone Diseases, Developmental/metabolism , Proprotein Convertases/genetics , Proprotein Convertases/metabolism , Protein Transport , Serine Endopeptidases/genetics , Serine Endopeptidases/metabolism , Apoptosis , Basic-Leucine Zipper Transcription Factors/metabolism , Bone Diseases, Developmental/physiopathology , Cell Culture Techniques , Child, Preschool , Chondrocytes/metabolism , Collagen/metabolism , Endoplasmic Reticulum/metabolism , Female , Gene Knockdown Techniques , Genetic Diseases, Inborn , Golgi Apparatus/metabolism , Homeostasis , Humans , Lipogenesis , Lysosomes/metabolism , Mannosephosphates , Mutation
16.
Bioinform Biol Insights ; 9(Suppl 3): 11-9, 2015.
Article in English | MEDLINE | ID: mdl-26512198

ABSTRACT

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by complex interplay among immune cell types. SLE activity is experimentally assessed by several blood tests, including gene expression profiling of heterogeneous populations of cells in peripheral blood. To better understand the contribution of different cell types in SLE pathogenesis, we applied the two methods in cell-type-specific differential expression analysis, csSAM and DSection, to identify cell-type-specific gene expression differences in heterogeneous gene expression measures obtained using RNA-seq technology. We identified B-cell-, monocyte-, and neutrophil-specific gene expression differences. Immunoglobulin-coding gene expression was altered in B-cells, while a ribosomal signature was prominent in monocytes. On the contrary, genes differentially expressed in the heterogeneous mixture of cells did not show any functional enrichment. Our results identify antigen binding and structural constituents of ribosomes as functions altered by B-cell- and monocyte-specific gene expression differences, respectively. Finally, these results position both csSAM and DSection methods as viable techniques for cell-type-specific differential expression analysis, which may help uncover pathogenic, cell-type-specific processes in SLE.

17.
Psychol Assess ; 27(1): 54-67, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25285718

ABSTRACT

The Sociocultural Attitudes Towards Appearance Questionnaire-3 (SATAQ-3) and its earlier versions are measures designed to assess societal and interpersonal aspects of appearance ideals. Correlational, structural equation modeling, and prospective studies of the SATAQ-3 have shown consistent and significant associations with measures of body image disturbance and eating pathology. In the current investigation, the SATAQ-3 was revised to improve upon some conceptual limitations and was evaluated in 4 U.S. and 3 international female samples, as well as a U.S. male sample. In Study 1, exploratory and confirmatory factor analyses for a sample of women from the Southeastern United States (N = 859) indicated a 22-item scale with 5 factors: Internalization: Thin/Low Body Fat, Internalization: Muscular/Athletic, Pressures: Family, Pressures: Media, Pressures: Peers. This scale structure was confirmed in 3 independent and geographically diverse samples of women from the United States (East Coast N = 440, West Coast N = 304, and North/Midwest N = 349). SATAQ-4 scale scores demonstrated excellent reliability and good convergent validity with measures of body image, eating disturbance, and self-esteem. Study 2 replicated the factorial validity, reliability, and convergent validity of the SATAQ-4 in an international sample of women drawn from Italy, England, and Australia (N = 362). Study 3 examined a sample of college males from the United States (N = 271); the 5-factor solution was largely replicated, yet there was some evidence of an underlying structure unique to men. Future research avenues include additional item testing and modification of the scale for men, as well as adaptation of the measure for children and adolescents.


Subject(s)
Attitude , Body Image , Cultural Characteristics , Self Concept , Social Perception , Surveys and Questionnaires , Adolescent , Adult , Australia , England , Factor Analysis, Statistical , Family , Female , Humans , Italy , Male , Mass Media , Peer Group , Prospective Studies , Reproducibility of Results , Surveys and Questionnaires/standards , United States
18.
Am J Hum Genet ; 94(4): 586-98, 2014 Apr 03.
Article in English | MEDLINE | ID: mdl-24702955

ABSTRACT

Efforts to identify lupus-associated causal variants in the FAM167A/BLK locus on 8p21 are hampered by highly associated noncausal variants. In this report, we used a trans-population mapping and sequencing strategy to identify a common variant (rs922483) in the proximal BLK promoter and a tri-allelic variant (rs1382568) in the upstream alternative BLK promoter as putative causal variants for association with systemic lupus erythematosus. The risk allele (T) at rs922483 reduced proximal promoter activity and modulated alternative promoter usage. Allelic differences at rs1382568 resulted in altered promoter activity in B progenitor cell lines. Thus, our results demonstrated that both lupus-associated functional variants contribute to the autoimmune disease association by modulating transcription of BLK in B cells and thus potentially altering immune responses.


Subject(s)
Lupus Erythematosus, Systemic/genetics , Promoter Regions, Genetic , Transcription, Genetic , src-Family Kinases/genetics , Alleles , Chromosomes, Human, Pair 8 , Electrophoretic Mobility Shift Assay , Female , Genetic Predisposition to Disease , Haplotypes , Humans , Male , Polymorphism, Single Nucleotide
19.
J Rheumatol ; 40(11): 1875-80, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24037550

ABSTRACT

OBJECTIVE: Patients with systemic lupus erythematosus (SLE) are at increased risk of herpes zoster (HZ). Although a vaccine for HZ has been approved by the US Food and Drug Administration, its use in immunocompromised individuals remains controversial because it is a live-attenuated virus vaccine. We performed a pilot study of the immunogenicity of the HZ vaccine (Zostavax) in patients with SLE. METHODS: Ten patients with SLE and 10 control subjects ≥ age 50 years participated in this open-label vaccination study. All were seropositive for varicella zoster virus (VZV). Patients with SLE were excluded for SLE Disease Activity Index (SLEDAI) > 4, or use of mycophenolate mofetil, cyclophosphamide, biologics, or > 10 mg prednisone daily. Followup visits occurred at 2, 6, and 12 weeks. Clinical outcomes included the development of adverse events, particularly HZ or vesicular lesions, and SLE flare. Immunogenicity was assessed with VZV-specific interferon-γ-producing enzyme-linked immunospot (ELISPOT) assays and with antibody concentrations. RESULTS: All subjects were women. Patients with SLE were slightly older than controls (60.5 vs 55.3 yrs, p < 0.05). Median baseline SLEDAI was 0 (range 0-2) for patients with SLE. No episodes of HZ, vesicular rash, serious adverse events, or SLE flares occurred. Three injection site reactions occurred in each group: mild erythema or tenderness. The proportion of subjects with a > 50% increase in ELISPOT results following vaccination was comparable between both groups, although absolute SLE responses were lower than controls. Antibody titers increased only among controls following vaccination (p < 0.05). CONCLUSION: The HZ vaccination yielded a measurable immune response in this cohort of patients with mild SLE taking mild-moderate immunosuppressive medications. No herpetiform lesions or SLE flares were seen in this small cohort of patients. ClinicalTrials.gov ID:NCT01474720.


Subject(s)
Herpes Zoster Vaccine/therapeutic use , Herpes Zoster/prevention & control , Herpesvirus 3, Human/immunology , Lupus Erythematosus, Systemic/immunology , Female , Herpes Zoster/immunology , Humans , Immunocompromised Host , Lupus Erythematosus, Systemic/virology , Middle Aged , Pilot Projects , Treatment Outcome
20.
Ann Rheum Dis ; 70(9): 1569-74, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21586442

ABSTRACT

OBJECTIVES: Vitamin D deficiency is widespread and has been associated with many chronic diseases, including autoimmune disorders. A study was undertaken to explore the impact of low vitamin D levels on autoantibody production in healthy individuals, as well as B cell hyperactivity and interferon α (IFNα) activity in patients with systemic lupus erythematosus (SLE). METHODS: Serum samples from 32 European American female patients with SLE and 32 matched controls were tested for 25-hydroxyvitamin D (25(OH)D) levels, lupus-associated autoantibodies and serum IFNα activity. Isolated peripheral blood mononuclear cells were tested for intracellular phospho-ERK 1/2 as a measure of B cell activation status. RESULTS: Vitamin D deficiency (25(OH)D <20 ng/ml) was significantly more frequent among patients with SLE (n=32, 69%) and antinuclear antibody (ANA)-positive controls (n=14, 71%) compared with ANA-negative controls (n=18, 22%) (OR 7.7, 95% CI 2.0 to 29.4, p=0.003 and OR 8.8, 95% CI 1.8 to 43.6, p=0.011, respectively). Patients with high B cell activation had lower mean (SD) 25(OH)D levels than patients with low B cell activation (17.2 (5.1) vs 24.2 (3.9) ng/ml; p=0.009). Patients with vitamin D deficiency also had higher mean (SD) serum IFNα activity than patients without vitamin D deficiency (3.5 (6.6) vs 0.3 (0.3); p=0.02). CONCLUSIONS: The observation that ANA-positive healthy controls are significantly more likely to be deficient in vitamin D than ANA-negative healthy controls, together with the finding that vitamin D deficiency is associated with certain immune abnormalities in SLE, suggests that vitamin D plays an important role in autoantibody production and SLE pathogenesis.


Subject(s)
Lupus Erythematosus, Systemic/etiology , Vitamin D Deficiency/complications , Vitamin D Deficiency/immunology , Antibodies, Antinuclear/blood , Autoimmunity/immunology , B-Lymphocytes/immunology , Case-Control Studies , Female , Humans , Interferon-alpha/blood , Lupus Erythematosus, Systemic/immunology , Lymphocyte Activation/immunology , Vitamin D/analogs & derivatives , Vitamin D/blood
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