RESUMO
OBJECTIVE: To characterise the molecular pathways impacted by the pharmacologic effects of the Janus kinase (JAK) 1 and JAK2 inhibitor baricitinib in SLE. METHODS: In a phase II, 24-week, randomised, placebo-controlled, double-blind study (JAHH), RNA was isolated from whole blood in 274 patients and analysed using Affymetrix HTA2.0 array. Serum cytokines were measured using ultrasensitive quantitative assays. RESULTS: Gene expression profiling demonstrated an elevation of STAT1, STAT2 and multiple interferon (IFN) responsive genes at baseline in patients with SLE. Statistical and gene network analyses demonstrated that baricitinib treatment reduced the mRNA expression of functionally interconnected genes involved in SLE including STAT1-target, STAT2-target and STAT4-target genes and multiple IFN responsive genes. At baseline, serum cytokines IFN-α, IFN-γ, interleukin (IL)-12p40 and IL-6 were measurable and elevated above healthy controls. Treatment with baricitinib significantly decreased serum IL-12p40 and IL-6 cytokine levels at week 12, which persisted through week 24. CONCLUSION: Baricitinib treatment induced significant reduction in the RNA expression of a network of genes associated with the JAK/STAT pathway, cytokine signalling and SLE pathogenesis. Baricitinib consistently reduced serum levels of two key cytokines implicated in SLE pathogenesis, IL-12p40 and IL-6.
Assuntos
Azetidinas/uso terapêutico , Lúpus Eritematoso Sistêmico , Purinas/uso terapêutico , Pirazóis/uso terapêutico , Sulfonamidas/uso terapêutico , Adulto , Feminino , Expressão Gênica , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Masculino , Pessoa de Meia-IdadeRESUMO
Systemic lupus erythematosus (SLE) is a chronic, remitting, and relapsing, inflammatory disease involving multiple organs, which exhibits abnormalities of both the innate and adaptive immune responses. A limited number of transcriptomic studies have characterized the gene pathways involved in SLE in an attempt to identify the key pathogenic drivers of the disease. In order to further advance our understanding of the pathogenesis of SLE, we used a novel Bayesian network algorithm to hybridize knowledge- and data-driven methods, and then applied the algorithm to build an SLE gene network using transcriptomic data from 1,760 SLE patients' RNA from the two tabalumab Phase III trials (ILLUMINATE-I & -II), the largest SLE RNA dataset to date. Further, based on the gene network, we carried out hub- and key driver-gene analyses for gene prioritization. Our analyses identified that the JAK-STAT pathway genes, including JAK2, STAT1, and STAT2, played essential roles in SLE pathogenesis, and reaffirmed the recent discovery of pathogenic relevance of JAK-STAT signaling in SLE. Additionally, we showed that other genes, such as IRF1, IRF7, PDIA4, FAM72C, TNFSF10, DHX58, SIGLEC1, and PML, may be also important in SLE and serve as potential therapeutic targets for SLE. In summary, using a hybridized network construction approach, we systematically investigated gene-gene interactions based on their transcriptomic profiles, prioritized genes based on their importance in the network structure, and revealed new insights into SLE activity.
Assuntos
Redes Reguladoras de Genes/imunologia , Lúpus Eritematoso Sistêmico/genética , Modelos Genéticos , Transdução de Sinais/genética , Algoritmos , Teorema de Bayes , Ensaios Clínicos Fase III como Assunto , Simulação por Computador , Mineração de Dados , Conjuntos de Dados como Assunto , Perfilação da Expressão Gênica , Humanos , Janus Quinase 2/imunologia , Janus Quinase 2/metabolismo , Modelos Lineares , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/imunologia , Análise de Sequência com Séries de Oligonucleotídeos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fator de Transcrição STAT1/imunologia , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT2/imunologia , Fator de Transcrição STAT2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologiaRESUMO
BACKGROUND: Patients with systemic lupus erythematosus have substantial unmet medical need. Baricitinib is an oral selective Janus kinase (JAK)1 and JAK2 inhibitor that we hypothesised might have therapeutic benefit in patients with systemic lupus erythematosus. METHODS: In this double-blind, multicentre, randomised, placebo-controlled, 24-week phase 2 study, patients were recruited from 78 centres in 11 countries. Eligible patients were aged 18 years or older, had a diagnosis of systemic lupus erythematosus, and had active disease involving skin or joints. We randomly assigned patients (1:1:1) to receive once-daily baricitinib 2 mg, baricitinib 4 mg, or placebo for 24 weeks. The primary endpoint was the proportion of patients achieving resolution of arthritis or rash at week 24, as defined by Systemic Lupus Erythematosus Disease Activity Index-2000 (SLEDAI-2K). Efficacy and safety analyses included all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, number NCT02708095. FINDINGS: Between March 24, 2016, and April 27, 2017, 314 patients were randomly assigned to receive placebo (n=105), baricitinib 2 mg (n=105), or baricitinib 4 mg (n=104). At week 24, resolution of SLEDAI-2K arthritis or rash was achieved by 70 (67%) of 104 patients receiving baricitinib 4 mg (odds ratio [OR] vs placebo 1·8, 95% CI 1·0-3·3; p=0·0414) and 61 (58%) of 105 patients receiving baricitinib 2 mg (OR 1·3, 0·7-2·3; p=0·39). Adverse events were reported in 68 (65%) patients in the placebo group, 75 (71%) patients in the baricitinib 2 mg group, and 76 (73%) patients in the baricitinib 4 mg group. Serious adverse events were reported in ten (10%) patients receiving baricitinib 4 mg, 11 (10%) receiving baricitinib 2 mg, and five (5%) receiving placebo; no deaths were reported. Serious infections were reported in six (6%) patients with baricitinib 4 mg, two (2%) with baricitinib 2 mg, and one (1%) with placebo. INTERPRETATION: The baricitinib 4 mg dose, but not the 2 mg dose, significantly improved the signs and symptoms of active systemic lupus erythematosus in patients who were not adequately controlled despite standard of care therapy, with a safety profile consistent with previous studies of baricitinib. This study provides the foundation for future phase 3 trials of JAK1/2 inhibition with baricitinib as a new potential oral therapy for systemic lupus erythematosus. FUNDING: Eli Lilly and Company.
Assuntos
Artrite/tratamento farmacológico , Azetidinas/administração & dosagem , Exantema/tratamento farmacológico , Inibidores de Janus Quinases/administração & dosagem , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Sulfonamidas/administração & dosagem , Administração Oral , Adulto , Azetidinas/efeitos adversos , Colesterol/sangue , HDL-Colesterol/sangue , Creatina Quinase/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Infecções/epidemiologia , Inibidores de Janus Quinases/efeitos adversos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Purinas , Pirazóis , Sulfonamidas/efeitos adversosRESUMO
OBJECTIVE: To characterize baseline gene expression and pharmacodynamically induced changes in whole blood gene expression in 1,760 systemic lupus erythematosus (SLE) patients from 2 phase III, 52-week, randomized, placebo-controlled, double-blind studies in which patients were treated with the BAFF-blocking IgG4 monoclonal antibody tabalumab. METHODS: Patient samples were obtained from SLE patients from the ILLUMINATE-1 and ILLUMINATE-2 studies, and control samples were obtained from healthy donors. Blood was collected in Tempus tubes at baseline, week 16, and week 52. RNA was analyzed using Affymetrix Human Transcriptome Array 2.0 and NanoString. RESULTS: At baseline, expression of the interferon (IFN) response gene was elevated in patients compared with controls, with 75% of patients being positive for this IFN response gene signature. There was, however, substantial heterogeneity of IFN response gene expression and complex relationships among gene networks. The IFN response gene signature was a predictor of time to disease flare, independent of anti-double-stranded DNA (anti-dsDNA) antibody and C3 and C4 levels, and overall disease activity. Pharmacodynamically induced changes in gene expression following tabalumab treatment were extensive, occurring predominantly in B cell-related and immunoglobulin genes, and were consistent with other pharmacodynamic changes including anti-dsDNA antibody, C3, and immunoglobulin levels. CONCLUSION: SLE patients demonstrated increased expression of an IFN response gene signature (75% of patients had an elevated IFN response gene signature) at baseline in ILLUMINATE-1 and ILLUMINATE-2. Substantial heterogeneity of gene expression was detected among individual patients and in gene networks. The IFN response gene signature was an independent risk factor for future disease flares. Pharmacodynamic changes in gene expression were consistent with the mechanism of BAFF blockade by tabalumab.
Assuntos
Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Fator Ativador de Células B/antagonistas & inibidores , Expressão Gênica/genética , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados , Método Duplo-Cego , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemAssuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Citocinas/metabolismo , Interleucina-17/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Psoríase/tratamento farmacológico , Psoríase/metabolismo , Anticorpos Monoclonais/uso terapêutico , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Infusões Intravenosas , Injeções Subcutâneas , Interleucina-17/administração & dosagem , Interleucina-17/imunologia , Monócitos/patologia , Receptores de Quimiocinas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Resultado do TratamentoRESUMO
Mixed Connective Tissue Disease (MCTD) and Systemic Lupus Erythematosus (SLE) are autoimmune rheumatic diseases that are difficult for physicians to diagnose and to distinguish for a variety of reasons. The correct classification of these two diseases is a crucial issue for clinicians who treat autoimmune rheumatic diseases. In prior research, medical risk factors represented by instrument or laboratory measures and physician judgments (12 key features for MCTD and 12 key features for SLE) were parameterized with a one parameter logistic function in a Rasch model. Those results identified separate diagnostic dimensions for MCTD and SLE. This procedure was replicated in the present research with a sample of largely African American and Hispanic patients. Results verified separate dimensions for MCTD and SLE, which suggests MCTD is a separate disease from SLE.
Assuntos
Interpretação Estatística de Dados , Técnicas de Apoio para a Decisão , Diagnóstico por Computador/métodos , Lúpus Eritematoso Sistêmico/classificação , Lúpus Eritematoso Sistêmico/diagnóstico , Doença Mista do Tecido Conjuntivo/classificação , Doença Mista do Tecido Conjuntivo/diagnóstico , Diagnóstico Diferencial , Humanos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: In subjects with psoriasis, inflammation and epidermal hyperplasia are thought to be controlled by T cell-derived cytokines. Evidence suggests that the T(H)17 cell cytokine IL-17A (IL-17) might play a role in disease pathogenesis. OBJECTIVE: We sought to understand the effect that neutralization of IL-17 has on the clinical features of psoriasis and to understand the role that IL-17 has in inflammatory pathways underlying psoriasis in human subjects. METHODS: We examined skin lesions obtained from 40 subjects participating in a phase I, randomized, double-blind, placebo-controlled trial of the anti-IL-17 mAb ixekizumab (previously LY2439821) in which subjects received 5, 15, 50, or 150 mg of subcutaneous ixekizumab or placebo at weeks 0, 2, and 4. RESULTS: There were significant dose-dependent reductions from baseline in keratinocyte proliferation, hyperplasia, epidermal thickness, infiltration into the dermis and epidermis by T cells and dendritic cells, and keratinocyte expression of innate defense peptides at 2 weeks. By week 6, the skin appeared normal. Quantitative RT-PCR and microarrays revealed an ablation of the disease-defining mRNA expression profile by 2 weeks after the first dose of study drug. The effect of IL-17 blockade on expression of genes synergistically regulated by IL-17 and TNF-α was of higher magnitude at 2 weeks than in prior studies with TNF-α antagonism. CONCLUSION: Our data suggest that IL-17 is a key "driver" cytokine that activates pathogenic inflammation in subjects with psoriasis. Neutralizing IL-17 with ixekizumab might be a successful therapeutic strategy in psoriasis.
Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Interleucina-17/metabolismo , Psoríase/fisiopatologia , Psoríase/terapia , Células Th17/imunologia , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/imunologia , Relação Dose-Resposta a Droga , Humanos , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Interleucina-17/genética , Interleucina-17/imunologia , Ativação Linfocitária , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Psoríase/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pele/imunologia , Pele/metabolismo , Pele/fisiopatologia , Resultado do Tratamento , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
To establish the relevance of targeting disease-associated T cells in anti-RNP-associated glomerulonephritis, mice developing nephritis following immunization with U1-70-kd small nuclear ribonucleoprotein (snRNP) were treated with a single dose of irradiated antigen-selected T cell vaccine. T cell receptor usage in nephritic kidneys revealed oligoclonal use of T Cell Receptor V Beta (TRBV) genes as previously found in spleens and lungs of immunized mice with pulmonary disease. The CDR3 regions from T cell isolates showed sequence homology to those in humans with anti-RNP autoimmunity. Following T cell vaccination, urinalysis returned to normal in 5/7 treated mice (71% response rate) whereas all mock-treated mice continued to have an active urinary sediment (Fisher's Exact p=0.02). An oligoclonal population of T cells homologous to those identified in humans with anti-RNP autoimmunity is implicated in disease pathogenesis, and T cell vaccination is associated with a high rate of clinical improvement in established nephritis.
Assuntos
Nefrite Lúpica/terapia , Ribonucleoproteína Nuclear Pequena U1/imunologia , Linfócitos T/imunologia , Vacinação/métodos , Sequência de Aminoácidos/genética , Animais , Autoanticorpos/sangue , Autoanticorpos/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Proliferação de Células , Regiões Determinantes de Complementaridade/genética , Antígenos HLA-DR/genética , Humanos , Glomérulos Renais/patologia , Nefrite Lúpica/imunologia , Nefrite Lúpica/patologia , Nefrite Lúpica/urina , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Ribonucleoproteína Nuclear Pequena U1/genética , Baço/citologia , Baço/imunologia , Linfócitos T/patologia , UrináliseRESUMO
OBJECTIVE: To explore the role of immune cells in anti-RNP autoimmunity in a murine model of pneumonitis or glomerulonephritis, using adoptive transfer techniques. METHODS: Donor mice were immunized with 50 mug of U1-70-kd small nuclear RNP fusion protein and 50 mug of U1 RNA adjuvant. Whole splenocytes as well as CD4+ cell and dendritic cell (DC) subsets from the immunized mice were infused into naive syngeneic recipients. Anti-RNP and T cell responses were assessed by immunoblotting, enzyme-linked immunosorbent assay, and flow cytometry. Development of renal or lung disease was assessed by histology and urinalysis. RESULTS: Unfractionated splenocytes from donor mice without proteinuria induced predominantly lung disease in recipients (8 [57%] of 14 versus 2 [14%] of 14 developing renal disease; P = 0.046). However, infusion of CD4+ cells from donors without proteinuria induced renal disease more frequently than lung disease (7 [70%] of 10 versus 2 [20%] of 10; P = 0.01); adoptive transfer of RNP+CD4+ T cells from short-term culture yielded similar results (renal disease in 8 [73%] of 11 recipients versus lung disease in 3 [27%] of 11). Cotransfer of splenic myeloid DCs and CD4+ T cells from immunized donors prevented induction of renal disease in all 5 recipients (P = 0.026 versus recipients of fresh CD4+ cells alone), although lung disease was still observed in 1 of 5 mice. Transfer of myeloid DCs alone from immunized donors induced lung disease in 3 (60%) of 5 recipients, without evidence of nephritis. Cotransfer of splenocytes from mice with and those without nephritis led to renal disease in 4 of 5 recipients, without evidence of lung disease. CONCLUSION: These findings indicate that RNP+CD4+ T cells are sufficient to induce anti-RNP autoimmunity, tissue targeting in anti-RNP autoimmunity can be deviated to either a renal or pulmonary phenotype depending on the presence of accessory cells such as myeloid DCs, and DC subsets can play a role in both propagation of autoimmunity and end-organ targeting.
Assuntos
Autoimunidade/imunologia , Linfócitos T CD4-Positivos/transplante , Células Dendríticas/imunologia , Células Mieloides/imunologia , Ribonucleoproteína Nuclear Pequena U1/imunologia , Linfócitos T/imunologia , Transferência Adotiva , Animais , Transplante de Células , Células Cultivadas , Células Dendríticas/transplante , Modelos Animais de Doenças , Glomerulonefrite/imunologia , Glomerulonefrite/patologia , Glomerulonefrite/urina , Doenças Pulmonares Intersticiais/imunologia , Doenças Pulmonares Intersticiais/patologia , Doenças Pulmonares Intersticiais/urina , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Mieloides/transplante , Proteinúria , Ribonucleoproteína Nuclear Pequena U1/administração & dosagem , Baço/citologia , Baço/imunologia , Linfócitos T/transplanteRESUMO
The associations of circulating 20S proteasomes (c20S) with clinical and serologic disease indices in patients with systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD) are unknown. We present the initial report that c20S levels are elevated in MCTD and correlate with clinically relevant changes in disease activity in SLE and MCTD.
Assuntos
Lúpus Eritematoso Sistêmico/fisiopatologia , Doença Mista do Tecido Conjuntivo/fisiopatologia , Complexo de Endopeptidases do Proteassoma/sangue , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estatística como AssuntoRESUMO
Mixed connective tissue disease (MCTD) is a systemic autoimmune disease with significant morbidity and premature mortality of unknown pathogenesis. In the present study, we characterized U1-70-kDa small nuclear ribonucleoprotein (70-kDa) autoantigen-specific T cells in a new murine model of MCTD. These studies defined 70-kDa-reactive T cell Ag fine specificities and TCR gene usage in this model. Similar to patients with MCTD, CD4(+) T cells can be readily identified from 70-kDa/U1-RNA-immunized HLA-DR4-transgenic mice. Using both freshly isolated CD4(+) T cells from spleen and lung, and T cell lines, we found that the majority of these T cells were directed against antigenic peptides residing within the RNA-binding domain of 70 kDa. We also found that TCR-beta (TRB) V usage was highly restricted among 70-kDa-reactive T cells, which selectively used TRBV subgroups 1, 2, 6, 8.1, 8.2, and 8.3, and that the TRB CDR3 had conserved sequence motifs which were shared across different TRBV subgroups. Finally, we found that the TRBV and CDR3 regions used by both murine and human 70-kDa-specific CD4(+) T cells were homologous. Thus, T cell recognition of the 70-kDa autoantigen by HLA-DR4-transgenic mice is focused on a limited number of T cell epitopes residing primarily within the RBD of the molecule, using a restricted number of TRBV and CDR3 motifs that are homologous to T cells isolated from MCTD patients.
Assuntos
Autoantígenos/metabolismo , Linfócitos T CD4-Positivos/imunologia , Epitopos de Linfócito T/metabolismo , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Antígeno HLA-DR4/genética , Doença Mista do Tecido Conjuntivo/imunologia , Ribonucleoproteína Nuclear Pequena U1/imunologia , Ribonucleoproteínas Nucleares Pequenas/imunologia , Sequência de Aminoácidos , Animais , Autoanticorpos/biossíntese , Autoantígenos/administração & dosagem , Autoantígenos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linhagem Celular , Movimento Celular/genética , Movimento Celular/imunologia , Modelos Animais de Doenças , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Antígenos HLA-A/administração & dosagem , Antígenos HLA-A/genética , Antígenos HLA-A/imunologia , Antígenos HLA-DR/administração & dosagem , Antígenos HLA-DR/genética , Antígenos HLA-DR/imunologia , Cadeias HLA-DRB1 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Doença Mista do Tecido Conjuntivo/genética , Doença Mista do Tecido Conjuntivo/patologia , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Ribonucleoproteína Nuclear Pequena U1/administração & dosagem , Ribonucleoproteína Nuclear Pequena U1/metabolismo , Ribonucleoproteínas Nucleares Pequenas/administração & dosagem , Ribonucleoproteínas Nucleares Pequenas/metabolismoRESUMO
The classification of rheumatic diseases is challenging because these diseases have protean and frequently overlapping clinical and laboratory manifestations. This problem is typified by the difficulty of classification and differentiation of two prototypic multi-system autoimmune diseases, Systemic Lupus Erythematosus (SLE) and Mixed Connective Tissue Disease (MCTD). The researchers submitted medical risk factor data represented by instrument or laboratory measures and physician judgments (12 key features for SLE) from 43 patients diagnosed with SLE and 12 key features for MCTD from 51 patients diagnosed with MCTD to the WINSTEPS Rasch analysis program. Using Rasch model parameterization, and fit and residuals analyses, the researchers identified separate dimensions for MCTD and SLE, thereby lending support to the position that MCTD is its own separate disease, distinct from SLE.
Assuntos
Lúpus Eritematoso Sistêmico/classificação , Doença Mista do Tecido Conjuntivo/classificação , Psicometria , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Mista do Tecido Conjuntivo/fisiopatologia , Inquéritos e QuestionáriosRESUMO
Mixed Connective Tissue Disease (MCTD) was first described 35 years ago by Gordon C. Sharp and his colleagues. In the ensuing decades, a clearer understanding of the clinical and serologic features of MCTD has emerged. Classification criteria now exist to define MCTD for study purposes, the long-term outcome of the disease has been established, and novel genetic associations within the major histocompatibility complex on chromosome 6 and select regions on chromosome 3 have been identified. Studies on immune pathogenesis have made substantial progress in advancing our understanding of MCTD. In MCTD, there is a complex interaction of the innate and adaptive immune system that culminates in autoimmune disease. Antigenic structural modification occurring during apoptosis or other modifications of self antigens leads to an autoantigen driven immune process with innate immune activation, immunoglobulin G autoantibody production directed against select components of the spliceosome, B lymphocyte activation, and CD4 and CD8 T lymphocyte participation.
Assuntos
Doença Mista do Tecido Conjuntivo/imunologia , Autoanticorpos/imunologia , Autoantígenos/imunologia , Humanos , Doença Mista do Tecido Conjuntivo/classificação , Doença Mista do Tecido Conjuntivo/fisiopatologiaRESUMO
OBJECTIVE: A cross-sectional study of mixed connective tissue disease (MCTD) was performed to determine if there were identifiable differences in the clinical expression of MCTD associated with race or ethnicity. METHODS: Miami, Florida, and Midwestern US (Missouri) Caucasian MCTD cohorts were studied. Clinical and laboratory features of the 2 MCTD cohorts were compared. A concurrently collected cohort of Sm-positive patients with systemic lupus erythematosus (SLE) was studied as a control. Disease activity and severity and functional status were measured. CD4+CD25(high)-expressing T-regulatory cells were enumerated and serum soluble L selectin was measured as biomarkers of disease activity. RESULTS: The Miami and Missouri Caucasian MCTD groups, while differing from the SLE group, were largely similar; however, gastroesophageal reflux, sclerodactyly, and malar rash were significantly more frequent in the Missouri MCTD group and alopecia was more frequent in the Miami MCTD group. Significant clinical and laboratory differences were found between the Miami MCTD and Miami SLE groups despite similar disease duration, activity, severity and functional status. Raynaud's phenomenon (RP), hand swelling, synovitis, myositis, and sclerodactyly were all significantly more common in RNP-positive MCTD versus Sm-positive SLE subjects. CONCLUSION Ethnic differences were observed in the frequency of end-organ involvement in the Miami MCTD versus the Missouri Caucasian MCTD groups. Clinical and laboratory features of all MCTD groups were clearly different from the SLE group, despite similar disease activity, disease severity, and functional status. Disease activity measures appeared to behave similarly as valid measures of disease activity in SLE and MCTD.
Assuntos
Selectina L/sangue , Lúpus Eritematoso Sistêmico/imunologia , Doença Mista do Tecido Conjuntivo/etnologia , Doença Mista do Tecido Conjuntivo/imunologia , Linfócitos T Reguladores , Adolescente , Adulto , Negro ou Afro-Americano/etnologia , Idoso , Estudos de Casos e Controles , Estudos Transversais , Florida/epidemiologia , Hispânico ou Latino/etnologia , Humanos , Lúpus Eritematoso Sistêmico/etnologia , Pessoa de Meia-Idade , Missouri/epidemiologia , Índice de Gravidade de Doença , População Branca/etnologiaRESUMO
Systemic lupus erythematosus (SLE) is a complex autoimmune disease in which genetics is one of the underlying risk factors. Complicating the analysis of SLE is the fact that the phenotype is heterogeneous, with variations in clinical features, and subgroups are associated with a variety of different autoantibodies. Many association studies of candidate genes as well as linkage studies have generated significant results, highlighting the multigenetic component of the disease. Those findings need to be replicated by independent laboratories and many other genes still remain to be identified. Here, we present our findings on the first genome-wide association study performed in 105 Caucasian patients and controls using the Affymetrix NspI array. The SLE patients studied here were all characterized by the presence of autoantibodies against the U1-6 small nuclear ribonucleoprotein antigen spliceosomal complex. Testing each SNP individually for association with disease, we identified 7 markers with an uncorrected P-value < 0.0001. Of those, three were in reported regions of linkage, namely 20p12, 2q37, and 4p15. To increase the power of our study, we included 60 controls corresponding to the parents from the publicly available CEPH families. The analysis of the 165 cases and controls leads to 28 SNPs being associated with an uncorrected P-value < 0.0001.
Assuntos
Genoma Humano/genética , Lúpus Eritematoso Sistêmico/genética , Predisposição Genética para Doença/genética , Humanos , Lúpus Eritematoso Sistêmico/epidemiologia , Missouri/epidemiologia , Polimorfismo de Nucleotídeo Único/genéticaAssuntos
Tolerância Imunológica , Lúpus Eritematoso Sistêmico/imunologia , Síndrome de Sjogren/imunologia , Linfócitos T/imunologia , Animais , Anticorpos Antinucleares/biossíntese , Linfócitos B/imunologia , Epitopos de Linfócito T/imunologia , Antígenos HLA-DQ/imunologia , Antígeno HLA-DR3/imunologia , Humanos , Lúpus Eritematoso Sistêmico/fisiopatologia , Síndrome de Sjogren/fisiopatologiaRESUMO
OBJECTIVE: To assess the Y RNAs, a family of homologous RNAs that bind to the Ro autoantigen, for the ability to contribute to autoimmune disease by activating RNA-responsive Toll-like receptors (TLRs). METHODS: Using cell lines expressing or stably transfected with TLR-3, TLR-7, or TLR-8, we determined the patterns of RNA-specific TLR activation by in vitro transcripts of all of the known murine and human Y RNAs. Next, 8-10-week-old female mice were exposed to a single 50-microg subcutaneous injection of mouse Y1 or mouse Y3 RNA, and the effects were observed. RESULTS: Y RNA family members differed in their TLR reactivities. Both human and mouse Y3 RNAs, but not other human or mouse Y RNAs, prominently induced TLR-3 activation. Although most human and mouse Y RNAs activated TLR-7 efficiently, mouse Y3 RNA and human Y5 RNA did not. Single subcutaneous injections of mice with either mouse Y1 RNA or mouse Y3 RNA induced or inhibited lymphoid infiltrates in different target organs based on the Y RNA and TLR status of the mouse used. Mouse Y1 RNA induced kidney lesions in TLR-3-intact mice but not in TLR-3-knockout mice. In contrast, mouse Y3 RNA treatment was associated with nephritis in TLR-3-knockout mice but not in TLR-3-intact mice. Sialoadenitis developed in untreated TLR-3-/- mice and in TLR-3-/- mice treated with mouse Y3 RNA, but sialoadenitis was not present in TLR--/-) mice treated with mouse Y1 RNA. CONCLUSION: Y RNAs can induce innate immune responses and influence clinical manifestations of autoimmunity, suggesting that they are relevant to syndromes of anti-Ro autoimmunity. Distinct patterns of tissue targeting can be seen after exposure to different Y RNAs, in a pattern that correlates with the innate immune signals they induce. Thus, the balance of innate immune signals induced by exposure to endogenous Y RNAs may help determine the nature of the clinical syndrome in anti-Ro autoimmunity.
Assuntos
Autoantígenos/imunologia , Autoimunidade/imunologia , Nefrite/imunologia , RNA/imunologia , Sialadenite/imunologia , Animais , Autoantígenos/genética , Autoimunidade/genética , Linhagem Celular , Feminino , Humanos , Imunidade Inata/genética , Imunidade Inata/imunologia , Injeções Subcutâneas , Rim/imunologia , Rim/patologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Nefrite/etiologia , RNA/metabolismo , Ribonucleoproteínas/metabolismo , Glândulas Salivares/imunologia , Glândulas Salivares/patologia , Sialadenite/etiologia , Receptor 3 Toll-Like/imunologia , Receptor 3 Toll-Like/metabolismo , Receptor 7 Toll-Like/imunologia , Receptor 7 Toll-Like/metabolismo , Receptor 8 Toll-Like/imunologia , Receptor 8 Toll-Like/metabolismoRESUMO
Natural Abs and autoantibodies bind antigens displayed by ischemia-conditioned tissues, followed by complement activation and enhanced tissue injury during reperfusion. Anti-ribonucleoprotein (RNP) Ab is associated with lung disease in patients with autoimmune disease but it is not known whether these abs contribute to lung injury. Mesenteric I/R in mice leads to local and remote lung injury. Accordingly, we used this model to investigate whether anti-RNP Abs would reconstitute I/R damage with prominent lung damage in injury-resistant Rag1(-/-) animals. Rag1(-/-) mice injected with anti-RNP Ab containing serum and subjected to mesenteric I/R suffered greater intestinal injury than control-treated and sham-operated animals. The magnitude of the reconstituted damage was anti-RNP Ab titer-dependent. Anti-RNP Ab-treated animals demonstrated a dose-dependent increase in lung histologic injury scores compared to control and sham animals. Anti-RNP mediated injury was shown to be complement dependent. These experiments reveal a novel mechanism whereby anti-RNP Abs contributes to the development of pulmonary pathology in patients with autoimmune diseases following exposure of remote organs to I/R injury.
Assuntos
Anticorpos Antinucleares/fisiologia , Proteínas de Homeodomínio/genética , Pulmão/patologia , Traumatismo por Reperfusão/imunologia , Ribonucleoproteínas/imunologia , Regulação para Cima/imunologia , Animais , Intestinos/imunologia , Intestinos/patologia , Pulmão/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologiaRESUMO
OBJECTIVE: To test whether immunizing mice with autoantigens closely linked to mixed connective tissue disease (MCTD) could induce an MCTD-like clinical syndrome distinguishable from systemic lupus erythematosus (SLE). METHODS: Transgenic and knockout C57BL/6-derived mice were immunized subcutaneously at age 8-12 weeks with U1-70-kd small nuclear RNP (70K) fusion protein along with either Freund's complete adjuvant (CFA) or U1 RNA. After 2 months, mice were killed and analyzed histologically and serologically. RESULTS: Immunization of C57BL/6-derived mice transgenic for human HLA-DR4 with 70K and either CFA or U1 RNA led to anti-70K antibodies in 62% of mice (21 of 34), and diversified anti-RNP immune responses. MCTD-like lung disease also developed in 50% of immunized mice (17 of 34), and anti-70K antibodies were strongly correlated with lung disease. CFA and U1 RNA were comparably able to induce this syndrome. Mice deficient in Toll-like receptor 3 (TLR-3) also developed this same syndrome when immunized with 70K and CFA. However, TLR-3(-/-) mice failed to develop MCTD-like lung disease when treated with 70K and U1 RNA. Rather, TLR-3(-/-) mice immunized with 70K and U1 RNA developed an autoimmune syndrome characterized by glomerulonephritis typical of SLE. CONCLUSION: Exposure to 70K in an appropriate context is sufficient to induce autoimmunity and target organ injury consistent with MCTD. This system represents a new model of autoimmune interstitial lung disease, and establishes a closer link between anti-70K immunity and MCTD-like lung disease. Of note, changes in innate immune signaling can cause the same trigger to lead to the development of SLE-like nephritis rather than MCTD-like lung disease.