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1.
Nat Rev Rheumatol ; 16(1): 32-52, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31831878

RESUMO

The past century has been characterized by intensive efforts, within both academia and the pharmaceutical industry, to introduce new treatments to individuals with rheumatic autoimmune inflammatory diseases (RAIDs), often by 'borrowing' treatments already employed in one RAID or previously used in an entirely different disease, a concept known as drug repurposing. However, despite sharing some clinical manifestations and immune dysregulation, disease pathogenesis and phenotype vary greatly among RAIDs, and limited understanding of their aetiology has made repurposing drugs for RAIDs challenging. Nevertheless, the past century has been characterized by different 'waves' of repurposing. Early drug repurposing occurred in academia and was based on serendipitous observations or perceived disease similarity, often driven by the availability and popularity of drug classes. Since the 1990s, most biologic therapies have been developed for one or several RAIDs and then tested among the others, with varying levels of success. The past two decades have seen data-driven repurposing characterized by signature-based approaches that rely on molecular biology and genomics. Additionally, many data-driven strategies employ computational modelling and machine learning to integrate multiple sources of data. Together, these repurposing periods have led to advances in the treatment for many RAIDs.

4.
J Autoimmun ; : 102359, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31806421

RESUMO

Systemic lupus erythematosus (SLE) is a chronic, systemic autoimmune disease that causes damage to multiple organ systems. Despite decades of research and available murine models that capture some aspects of the human disease, new treatments for SLE lag behind other autoimmune diseases such as Rheumatoid Arthritis and Crohn's disease. Big data genomic assays have transformed our understanding of SLE by providing important insights into the molecular heterogeneity of this multigenic disease. Gene wide association studies have demonstrated more than 100 risk loci, supporting a model of multiple genetic hits increasing SLE risk in a non-linear fashion, and providing evidence of ancestral diversity in susceptibility loci. Epigenetic studies to determine the role of methylation, acetylation and non-coding RNAs have provided new understanding of the modulation of gene expression in SLE patients and identified new drug targets and biomarkers for SLE. Gene expression profiling has led to a greater understanding of the role of myeloid cells in the pathogenesis of SLE, confirmed roles for T and B cells in SLE, promoted clinical trials based on the prominent interferon signature found in SLE patients, and identified candidate biomarkers and cellular signatures to further drug development and drug repurposing. Gene expression studies are advancing our understanding of the underlying molecular heterogeneity in SLE and providing hope that patient stratification will expedite new therapies based on personal molecular signatures. Although big data analyses present unique interpretation challenges, both computationally and biologically, advances in machine learning applications may facilitate the ability to predict changes in SLE disease activity and optimize therapeutic strategies.

5.
Front Immunol ; 10: 2512, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31708928

RESUMO

Autoantibody production by plasma cells (PCs) plays a pivotal role in the pathogenesis of systemic lupus erythematosus (SLE). The molecular pathways by which B cells become pathogenic PC secreting autoantibodies in SLE are incompletely characterized. Histone deactylase 6 (HDAC6) is a unique cytoplasmic HDAC that modifies the interaction of a number of tubulin- associated proteins; inhibition of HDAC6 has been shown to be beneficial in murine models of SLE, but the downstream pathways accounting for the therapeutic benefit have not been clearly delineated. In the current study, we sought to determine whether selective HDAC6 inhibition would abrogate abnormal B cell activation in SLE. We treated NZB/W lupus mice with the selective HDAC6 inhibitor, ACY-738, for 4 weeks beginning at 20 weeks-of age. After only 4 weeks of treatment, manifestation of lupus nephritis (LN) were greatly reduced in these animals. We then used RNAseq to determine the genomic signatures of splenocytes from treated and untreated mice and applied computational cellular and pathway analysis to reveal multiple signaling events associated with B cell activation and differentiation in SLE that were modulated by HDAC6 inhibition. PC development was abrogated and germinal center (GC) formation was greatly reduced. When the HDAC6 inhibitor-treated lupus mouse gene signatures were compared to human lupus patient gene signatures, the results showed numerous immune, and inflammatory pathways increased in active human lupus were significantly decreased in the HDAC6 inhibitor treated animals. Pathway analysis suggested alterations in cellular metabolism might contribute to the normalization of lupus mouse spleen genomic signatures, and this was confirmed by direct measurement of the impact of the HDAC6 inhibitor on metabolic activities of murine spleen cells. Taken together, these studies show HDAC6 inhibition decreases B cell activation signaling pathways and reduces PC differentiation in SLE and suggest that a critical event might be modulation of cellular metabolism.

6.
ACR Open Rheumatol ; 1(4): 236-243, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31777799

RESUMO

Objective: The objective of this study is to assess criteria for gout remission and to use the results to inform criteria for a complete response (CR). Methods: A post hoc analysis of two clinical trials was undertaken to determine the frequency with which subjects with chronic refractory gout who were treated with pegloticase met remission criteria. Mixed modeling was then employed to identify the components that best correlated with time to maximum benefit. Results: Of the 56 subjects treated with biweekly pegloticase for whom adequate data were collected, 48.2% met the remission criteria. When subjects with persistent lowering of urate levels were examined separately, 27 of 32 (84.4%) met the criteria for remission. In contrast, even when the requirement for lowering of serum urate levels was waived, only 2 of 24 (8.3%) subjects without persistent lowering of urate levels and 0 of 43 subjects receiving placebo met criteria. Mixed modeling indicated that in addition to urate levels, assessment of tophi, swollen joints, and tender joints and patient global assessment best correlated with time to maximum benefit. Using these criteria of CR, 23 of the responders (71.9%) met the criteria. All patients who achieved a CR maintained it for a mean duration of 507.4 days. Finally, 64% of persistent responders to monthly pegloticase also met criteria for CR. Conclusion: These results have validated the proposed remission criteria for gout and have helped define criteria for CR in individuals with chronic gout treated with pegloticase. This composite CR index can serve as an evidence-based target to inform the design and end points of future clinical trials.

7.
Front Immunol ; 10: 2136, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31616406

RESUMO

Autoimmune diseases (AID) such as systemic lupus erythematosus (SLE), primary Sjögren's syndrome (pSS), and rheumatoid arthritis (RA) are chronic inflammatory diseases in which abnormalities of B cell function play a central role. Although it is widely accepted that autoimmune B cells are hyperactive in vivo, a full understanding of their functional status in AID has not been delineated. Here, we present a detailed analysis of the functional capabilities of AID B cells and dissect the mechanisms underlying altered B cell function. Upon BCR activation, decreased spleen tyrosine kinase (Syk) and Bruton's tyrosine kinase (Btk) phosphorylation was noted in AID memory B cells combined with constitutive co-localization of CD22 and protein tyrosine phosphatase (PTP) non-receptor type 6 (SHP-1) along with hyporesponsiveness to TLR9 signaling, a Syk-dependent response. Similar BCR hyporesponsiveness was also noted specifically in SLE CD27- B cells together with increased PTP activities and increased transcripts for PTPN2, PTPN11, PTPN22, PTPRC, and PTPRO in SLE B cells. Additional studies revealed that repetitive BCR stimulation of normal B cells can induce BCR hyporesponsiveness and that tissue-resident memory B cells from AID patients also exhibited decreased responsiveness immediately ex vivo, suggesting that the hyporesponsive status can be acquired by repeated exposure to autoantigen(s) in vivo. Functional studies to overcome B cell hyporesponsiveness revealed that CD40 co-stimulation increased BCR signaling, induced proliferation, and downregulated PTP expression (PTPN2, PTPN22, and receptor-type PTPs). The data support the conclusion that hyporesponsiveness of AID and especially SLE B cells results from chronic in vivo stimulation through the BCR without T cell help mediated by CD40-CD154 interaction and is manifested by decreased phosphorylation of BCR-related proximal signaling molecules and increased PTPs. The hyporesponsiveness of AID B cells is similar to a form of functional anergy.

9.
Sci Rep ; 9(1): 9617, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31270349

RESUMO

The integration of gene expression data to predict systemic lupus erythematosus (SLE) disease activity is a significant challenge because of the high degree of heterogeneity among patients and study cohorts, especially those collected on different microarray platforms. Here we deployed machine learning approaches to integrate gene expression data from three SLE data sets and used it to classify patients as having active or inactive disease as characterized by standard clinical composite outcome measures. Both raw whole blood gene expression data and informative gene modules generated by Weighted Gene Co-expression Network Analysis from purified leukocyte populations were employed with various classification algorithms. Classifiers were evaluated by 10-fold cross-validation across three combined data sets or by training and testing in independent data sets, the latter of which amplified the effects of technical variation. A random forest classifier achieved a peak classification accuracy of 83 percent under 10-fold cross-validation, but its performance could be severely affected by technical variation among data sets. The use of gene modules rather than raw gene expression was more robust, achieving classification accuracies of approximately 70 percent regardless of how the training and testing sets were formed. Fine-tuning the algorithms and parameter sets may generate sufficient accuracy to be informative as a standalone estimate of disease activity.

10.
J Rheumatol ; 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31203212

RESUMO

OBJECTIVE: To assess clinical benefit in patients with chronic refractory gout who did not meet the protocol-defined criteria of responders to pegloticase. METHODS: This analysis used results from 2 randomized controlled trials (ClinicalTrials.gov: NCT00325195, NCT01356498) to assess the clinical efficacy in responders and nonresponders to treatment (8 mg of pegloticase every 2 weeks). Serum urate was measured before each infusion and the following were recorded: assessment of gout flares, tophus reduction, patient's global assessment (PtGA), tender and swollen joints (TJC and SJC), pain using a 100-mm visual analog scale, and a variety of patient-reported outcomes [Medical Outcomes Study Short Form-36 questionnaire physical component summary score and arthritis-specific health index (ASHI) score]. RESULTS: The analysis included 36 persistent urate responders, 49 nonresponders, and 43 patients who received placebo. Results for both responders and nonresponders indicated significant reduction in tophi and improvements from baseline in PtGA, TJC, SJC, pain, and ASHI. No significant improvements were observed in the patients who received placebo. CONCLUSION: Chronic refractory gout patients not achieving protocol-defined persistent urate lowering still achieve significant clinical benefits with pegloticase treatment, suggesting that transient reduction in serum urate may result in sustained clinical benefit.

11.
Commun Biol ; 2: 140, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31044165

RESUMO

A role for interferon (IFN) in systemic lupus erythematosus (SLE) pathogenesis is inferred from the prominent IFN gene signature (IGS), but the major IFN species and its relationship to disease activity are unknown. A bioinformatic approach employing individual IFN species gene signatures to interrogate SLE microarray datasets demonstrates a putative role for numerous IFN species, with prominent expression of IFNB1 and IFNW signatures. In contrast with other SLE-affected organs, the IGS is less prominent in lupus nephritis. SLE patients with active and inactive disease have readily detectable IGS and the IGS changes synchronously with a monocyte signature but not disease activity, and is significantly related to monocyte transcripts. Monocyte over-expression of three times as many IGS transcripts as T and B cells and IGS retention in monocytes, but not T and B cells from inactive SLE patients contribute to the lack of correlation between the IGS and SLE disease activity.

12.
Hypertension ; 74(1): 95-101, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31079535

RESUMO

Serum urate is correlated with blood pressure (BP), and lowering urate may decrease BP, but a consistent effect has not been observed. Here, we evaluated whether pegloticase, a recombinant uricase conjugated to polyethylene glycol, which can lead to persistently low serum urate levels (<1 mg/dL), can modulate BP in subjects with chronic refractory gout. This post hoc analysis used results from two 6-month randomized clinical trials in which subjects were treated with 8 mg pegloticase every 2 or 4 weeks (q2w or q4w) or placebo. Responders in this study were defined as those individuals in whom a persistently low urate level (<6 mg/dL and usually <1 mg/dL) was maintained. Serial sitting BP was measured in 173 subjects, and estimated glomerular filtration rate was determined at baseline and after 3 and 6 months. Significant reductions in mean arterial pressure (MAP) from baseline to 6 months were noted in q2w responders ( P=0.0028), whereas reductions in MAP in other groups were not significant. Significant decreases in both systolic and diastolic BP paralleled the change in MAP. Of the 62% of q2w responders exhibiting persistent decreases in MAP, there were no significant differences in baseline age, sex, race, weight, body mass index, history of hypertension, hyperlipidemia, history of coronary artery disease, gout duration, MAP, serum urate, estimated glomerular filtration rate or urinary uric acid/creatinine ratio compared with those who did not lower MAP. No significant changes in estimated glomerular filtration rate occurred in any of the groups during the study. Responders to biweekly pegloticase who maintained a persistently lower serum urate level throughout the trial experienced significant reductions in both systolic and diastolic BP that were independent of changes in renal function. Clinical Trial Registration- URL: http://www.clinicaltrials.gov . Unique identifier: NCT00325195.


Assuntos
Supressores da Gota/uso terapêutico , Gota/tratamento farmacológico , Hipertensão/prevenção & controle , Polietilenoglicóis/uso terapêutico , Urato Oxidase/uso terapêutico , Adulto , Idoso , Determinação da Pressão Arterial/métodos , Doença Crônica , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Gota/complicações , Gota/diagnóstico , Humanos , Hipertensão/etiologia , Testes de Função Renal , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Prognóstico , Pontuação de Propensão , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Resultado do Tratamento , Ácido Úrico/sangue
14.
J Immunol ; 202(11): 3309-3317, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31019061

RESUMO

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the presence of low-density granulocytes (LDGs) with a heightened capacity for spontaneous NETosis, but the contribution of LDGs to SLE pathogenesis remains unclear. To characterize LDGs in human SLE, gene expression profiles derived from isolated LDGs were characterized by weighted gene coexpression network analysis, and a 92-gene module was identified. The LDG gene signature was enriched in genes related to neutrophil degranulation and cell cycle regulation. This signature was assessed in gene expression datasets from two large-scale SLE clinical trials to study associations between LDG enrichment, SLE manifestations, and treatment regimens. LDG enrichment in the blood was associated with corticosteroid treatment as well as anti-dsDNA, low serum complement, renal manifestations, and vasculitis, but the latter two of these associations were dependent on concomitant corticosteroid treatment. In addition, LDG enrichment was associated with enrichment of gene signatures induced by type I IFN and TNF irrespective of corticosteroid treatment. Notably, LDG enrichment was not found in numerous tissues affected by SLE. Comparison with relevant reference datasets indicated that LDG enrichment is likely reflective of increased granulopoiesis in the bone marrow and not peripheral neutrophil activation. The results have uncovered important determinants of the appearance of LDGs in SLE and have emphasized the likely role of LDGs in specific aspects of lupus pathogenesis.

15.
Artigo em Inglês | MEDLINE | ID: mdl-30843588

RESUMO

OBJECTIVES: To determine the characteristics and response to pegloticase of patients with chronic refractory gout with and without clinically apparent tophi. METHODS: Results from two randomized controlled trials of pegloticase in patients with chronic refractory gout with clinically apparent tophi or without tophi were used to assess baseline and on-treatment between-group differences. RESULTS: Patients with tophi were significantly older than those without tophi, had a significantly longer duration of disease, higher numbers of tender and swollen joints, higher Patient Global Assessment scores and Health Assessment Questionnaire-Disability Index scores, and lower Arthritis-Specific Health Index scores. Patients with tophaceous gout also had significantly lower scores for physical functioning, role physical, social functioning, and the physical component summary scores of the Short Form 36 vs patients without tophi. In addition, subjects with clinically apparent tophi had a significantly lower mean estimated glomerular filtration rate. Pegloticase treatment of tophaceous patients caused significant reductions in serum urate, flares, Patient Global Assessment, tender joints, swollen joints, Health Assessment Questionnaire-Disability Index, visual analogue scale pain and Short Form 36 Bodily Pain, whereas patients without tophi had significant improvement in serum urate, flares, Patient Global Assessment, tender joints, and Short Form 36 Bodily Pain, but not swollen joints, Health Assessment Questionnaire-Disability Index functional score or pain visual analogue scale. Treatment with pegloticase had no effect on estimated glomerular filtration rate despite significant lowering of the urinary uric acid: creatinine ratio. CONCLUSION: Patients with chronic refractory gout and clinically apparent tophi have more severe disease as well as reduced renal function. Both groups experienced significant clinical benefit with pegloticase treatment, although no change in renal function was noted.

17.
Ann Rheum Dis ; 78(6): 729-735, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30636212

RESUMO

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with a considerable impact on patients' quality of life. Despite the plethora of clinical trials for SLE since the turn of the millennium, only one new treatment has been approved for the condition, and the overall pace of successful drug development remains slow. Nevertheless, the myriad of clinical studies has yielded insights that have informed and refined our understanding of eligibility criteria, outcome measures and trial design in SLE. In this review, we highlight the achievements of clinical trials as well as the major pitfalls that have been identified in drug development for SLE and, in doing so, identify areas where collaboration and consensus will be important to facilitate progress.


Assuntos
Lúpus Eritematoso Sistêmico/tratamento farmacológico , Biomarcadores/sangue , Ensaios Clínicos como Assunto/métodos , Desenvolvimento de Medicamentos/métodos , Humanos , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/diagnóstico , Projetos de Pesquisa , Índice de Gravidade de Doença , Resultado do Tratamento
18.
Mod Rheumatol ; 29(3): 401-405, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-29848137

RESUMO

Nurse-like cells (NLCs) established from bone marrow and synovial tissue of rheumatoid arthritis (RA) patients were found to promote maturation and differentiation of B lineage cells as well as T cells. In co-culture of RA-NLCs and B cells, tight physical interactions (pseudoemperipolesis) developed, which resulted in activation of both cell types. RA-NLCs also supported myeloid cell maturation, promoting their differentiation into tartrate-resistant acid phosphatase-positive mononuclear cells, which are precursor cells of osteoclasts. In RA synovial tissue, the characteristic dendritic-shaped cells (the DCs) were electron microscopically found to form direct physical interactions with adjacent plasma cells (PCs) suspecting to be pseudoemperipolesis. The numbers of PCs accumulating in various areas tended to correlate with the numbers of the DCs, which appeared to have RA-NLC functions forming survival niches for PCs. Immunohistochemical staining analysis indicated that CD14+ cells including the DCs formed survival niches for CD138+ PCs by RA-NLC functions. Quantitative dual immunofluorescence staining studies of these areas indicated that the majority of CD14+ cells were of myeloid lineage. These survival niches promoted by RA-NLCs appear to play important roles in supporting immunological functions in RA bone marrow and synovial tissues.


Assuntos
Artrite Reumatoide/patologia , Comunicação Celular , Microambiente Celular , Sinoviócitos/citologia , Artrite Reumatoide/metabolismo , Linfócitos B/citologia , Linfócitos B/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Diferenciação Celular , Células Cultivadas , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Humanos , Osteoclastos/metabolismo , Sinoviócitos/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo
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