Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 44
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Pediatr Rheumatol Online J ; 17(1): 70, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31660995

RESUMO

BACKGROUND: Despite recent advances in the diagnosis and understanding of many autoinflammatory diseases, there are still a great number of patients with phenotypes that do not fit any clinically- and/or genetically-defined disorders. CASE PRESENTATION: We describe a fourteen-year-old boy who presented at two and a half years of age with recurrent febrile episodes. Over the course of the disease, the episodes increased in frequency and severity, with new signs and symptoms continuing to appear. Most importantly, these included skin changes, splenomegaly and transaminitis. Only partial control of the disease was achieved with anti-IL-1 therapy. Extensive investigation showed generalized inflammation without immune deficiency, with increased levels of serum amyloid A and several pro-inflammatory cytokines including interferon-γ, as well as an increased type I interferon score. Exome sequence analysis identified P369S and R408Q variants in the MEFV innate immunity regulator, pyrin (MEFV) gene and T260 M and T320 M variants in the NLR family pyrin domain containing 12 (NLRP12) gene. CONCLUSION: Patients with unclassified and/or unexplained autoinflammatory syndromes present diagnostic and therapeutic challenges and collectively form a substantial part of every cohort of patients with autoinflammatory diseases. Therefore, it is important to acquire their full genomic profile through whole exome and/or genome sequencing and present their cases to a broader audience, to facilitate characterization of similar patients. A critical mass of well-characterized cases will lead to improved diagnosis and informed treatment.

2.
BMC Res Notes ; 12(1): 511, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31416482

RESUMO

OBJECTIVE: Type I interferons (IFN) have important roles in many immune-mediated inflammatory diseases (IMIDs) and are a relatively new therapeutic target. Direct detection of type I IFNs has proved challenging, thus their presence is often inferred from the expression of interferon-stimulated genes (ISGs) and calculation of an interferon score (IS). The objective of this research was to determine if the expression of six common ISGs and subsequent IS were comparable when RNA was derived from the Tempus and PAXgene whole blood RNA collection systems. RESULTS: Whole blood was obtained from ten healthy adults, incubated ex vivo in the absence and presence of recombinant human IFNα then divided into PAXgene and Tempus tubes. Despite reports of tube-specific patterns of gene expression, quantitative PCR (qPCR) analysis revealed no significant differences between PAXgene and Tempus tubes in either the homeostatic or IFNα-induced expression of six ISGs (IFI27, IFI44L, IFIT1, ISG15, RSAD2, SIGLEC1). Overall there was a strong correlation in the IS between unstimulated (r = 0.92, p = 0.0005) and IFNα-stimulated (r = 0.71, p = 0.0268) samples derived from the PAXgene and Tempus tubes.


Assuntos
Coleta de Amostras Sanguíneas/métodos , Perfilação da Expressão Gênica/métodos , Interferon Tipo I/genética , RNA/genética , Adulto , Coleta de Amostras Sanguíneas/instrumentação , Feminino , Voluntários Saudáveis , Humanos , Interferon Tipo I/sangue , Masculino , RNA/sangue , RNA/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adulto Jovem
4.
Pediatr Rheumatol Online J ; 17(1): 22, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088470

RESUMO

Familial Mediterranean fever (FMF) is the most common monogenic autoinflammatory disease in Canada and is characterized by a clinical syndrome of episodic inflammatory symptoms. Traditionally, the disease is defined by autosomal recessive inheritance of MEFV gene variants, yet FMF also not uncommonly manifests in individuals with only one identified disease-associated allele. Increasing availability and affordability of gene sequencing has led to the identification of multiple MEFV variants; however, they are often of unknown clinical significance. Variants in other genes affecting overlapping or distinct inflammatory signaling pathways - together with gene-environment interactions including epigenetic modulation - likely underlie the significant genetic and phenotypic heterogeneity seen among patients with this disease. We review recent evidence of the expanding spectrum of FMF genotype and phenotype and suggest that current drug funding schemes restricting biologic agents to patients with homozygous mutations have not kept pace with our biological understanding of the disease.


Assuntos
Febre Familiar do Mediterrâneo/genética , Terapia Biológica/métodos , Criança , Febre Familiar do Mediterrâneo/diagnóstico , Febre Familiar do Mediterrâneo/terapia , Genótipo , Humanos , Mutação/genética , Pirina/genética , Pirina/metabolismo
5.
Arthritis Rheumatol ; 71(10): 1747-1755, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31008556

RESUMO

OBJECTIVE: Individuals with deficiency of adenosine deaminase 2 (DADA2), a recently recognized autosomal recessive disease, present with various systemic vascular and inflammatory manifestations, often with young age at disease onset or with early onset of recurrent strokes. Their clinical features and histologic findings overlap with those of childhood-onset polyarteritis nodosa (PAN), a primary "idiopathic" systemic vasculitis. Despite similar clinical presentation, individuals with DADA2 may respond better to biologic therapy than to traditional immunosuppression. The aim of this study was to screen an international registry of children with systemic primary vasculitis for variants in ADA2. METHODS: The coding exons of ADA2 were sequenced in 60 children and adolescents with a diagnosis of PAN, cutaneous PAN, or unclassifiable vasculitis (UCV), any chronic vasculitis with onset at age 5 years or younger, or history of stroke. The functional consequences of the identified variants were assessed by ADA2 enzyme assay and immunoblotting. RESULTS: Nine children with DADA2 (5 with PAN, 3 with UCV, and 1 with antineutrophil cytoplasmic antibody-associated vasculitis) were identified. Among them, 1 patient had no rare variants in the coding region of ADA2 and 8 had biallelic, rare variants (minor allele frequency <0.01) with a known association with DADA2 (p.Gly47Arg and p.Gly47Ala) or a novel association (p.Arg9Trp, p.Leu351Gln, and p.Ala357Thr). The clinical phenotype varied widely. CONCLUSION: These findings support previous observations indicating that DADA2 has extensive genotypic and phenotypic variability. Thus, screening ADA2 among children with vasculitic rash, UCV, PAN, or unexplained, early-onset central nervous system disease with systemic inflammation may enable an earlier diagnosis of DADA2.

6.
Clin Exp Rheumatol ; 37(6): 1077-1083, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30943143

RESUMO

Type I interferons (IFN) are a class of inducible and protective cytokines best known for immune defence against viruses and intracellular bacteria. Inappropriate stimulation or defective negative regulation of type I IFN expression however can lead to persistent type I IFN activity with detrimental effects. This is particularly relevant for a class of monogenic autoinflammatory diseases ("type I interferonopathies"), along with many other complex rheumatic diseases such as systemic lupus erythematosus (SLE), dermatomyositis (DM), systemic sclerosis (SSc), rheumatoid arthritis (RA) and Sjögren's syndrome (SS). Direct detection of type I interferon protein in biologic samples has proved challenging, thus indirect methods are often used to infer the presence of type I IFN via quantification of antiviral activity and/or induced expression of IFN-responsive genes. While some of these methods have been used to inform clinical care, none have proven feasible for everyday clinical practice. However, with new technologies emerging, this may soon change. This review provides a brief summary of the available methods to gauge the presence of type I IFN and their application for the improved understanding, diagnosis and monitoring of type I interferonopathies and other rheumatic diseases.


Assuntos
Artrite Reumatoide , Interferon Tipo I , Lúpus Eritematoso Sistêmico , Doenças Reumáticas , Síndrome de Sjogren , Artrite Reumatoide/sangue , Artrite Reumatoide/imunologia , Humanos , Interferon Tipo I/sangue , Interferon Tipo I/imunologia , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/imunologia , Doenças Reumáticas/sangue , Doenças Reumáticas/imunologia , Síndrome de Sjogren/sangue , Síndrome de Sjogren/imunologia
7.
Arthritis Rheumatol ; 71(5): 792-804, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30447136

RESUMO

OBJECTIVE: Kawasaki disease (KD) is an acute vasculitis of childhood, predominantly affecting the coronary arteries. S100A12, a granulocyte-derived agonist of both the receptor for advanced glycation end products (RAGE) and Toll-like receptor 4 (TLR-4), is strongly up-regulated in KD. This study was undertaken to investigate the potential contributions of S100A12 to the pathogenesis of KD. METHODS: Serum samples from patients with KD (n = 30) at different stages pre- and post-intravenous immunoglobulin (IVIG) treatment were analyzed for the expression of S100A12, cytokines, chemokines, and soluble markers of endothelial cell activation. Primary human coronary artery endothelial cells (HCAECs) were analyzed for responsiveness to direct stimulation with S100A12 or lipopolysaccharide (LPS), as assessed by real-time quantitative reverse transcription-polymerase chain reaction analysis of cytokine and endothelial cell adhesion molecule messenger RNA expression. Alternatively, HCAECs were cultured in conditioned medium obtained from primary human monocytes that were stimulated with LPS or S100A12 in the absence or presence of IVIG or cytokine antagonists. RESULTS: In the serum of patients with KD, pretreatment S100A12 levels were associated with soluble vascular cell adhesion molecule 1 titers in the course of IVIG therapy (rs = -0.6, P = 0.0003). Yet, HCAECs were not responsive to direct S100A12 stimulation, despite the presence of appropriate receptors (RAGE, TLR-4). HCAECs did, however, respond to supernatants obtained from S100A12-stimulated primary human monocytes, as evidenced by the gene expression of inflammatory cytokines and adhesion molecules. This response was strictly dependent on interleukin-1ß (IL-1ß) signaling (P < 0.001). CONCLUSION: In its role as a highly expressed mediator of sterile inflammation in KD, S100A12 appears to activate HCAECs in an IL-1ß-dependent manner. These data provide new mechanistic insights into the contributions of S100A12 and IL-1ß to disease pathogenesis, and may therefore support current IL-1-targeting studies in the treatment of patients with KD.


Assuntos
Células Endoteliais/metabolismo , Interleucina-1beta/imunologia , Síndrome de Linfonodos Mucocutâneos/metabolismo , Proteína S100A12/metabolismo , Estudos de Casos e Controles , Criança , Pré-Escolar , Aneurisma Coronário/etiologia , Aneurisma Coronário/imunologia , Aneurisma Coronário/metabolismo , Vasos Coronários , Citocinas/genética , Citocinas/imunologia , Células Endoteliais/imunologia , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Lactente , Lipopolissacarídeos , Masculino , Monócitos/imunologia , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/imunologia , Síndrome de Linfonodos Mucocutâneos/terapia , Cultura Primária de Células , Molécula 1 de Adesão de Célula Vascular/metabolismo
8.
Front Pediatr ; 6: 341, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30533405

RESUMO

Objectives: Chronic primary systemic vasculitidies (CPV) are a collection of rare diseases involving inflammation in blood vessels, often in multiple organs. CPV can affect adults and children and may be life- or organ-threatening. Treatments for adult CPV, although effective, have known severe potential toxicities; safety and efficacy of these drugs in pediatric patients is not fully understood. There is an unmet need for biologic measures to assess the level of disease activity and, in turn, inform treatment choices for stopping, starting, or modifying therapy. This observational study determines if S100 calcium-binding protein A12 (S100A12) and common inflammatory indicators are sensitive markers of disease activity in children and adolescents with CPV that could be used to inform a minimal effective dose of therapy. Methods: Clinical data and sera were collected from 56 participants with CPV at study visits from diagnosis to remission. Serum concentrations of S100A12, C-reactive protein (CRP) and hemoglobin (Hb) as well as whole blood cell counts and erythrocyte sedimentation rate (ESR) were measured. Disease activity was inferred by physician's global assessment (PGA) and the pediatric vasculitis activity score (PVAS). Results: Serum concentrations of standard markers of inflammation (ESR, CRP, Hb, absolute blood neutrophil count), and S100A12 track with clinically assessed disease activity. These measures-particularly neutrophil counts and sera concentrations of S100A12-had the most significant correlation with clinical scores of disease activity in those children with vasculitis that is associated with anti-neutrophil cytoplasmic antibodies (ANCA) against proteinase 3. Conclusions: S100A12 and neutrophil counts should be considered in the assessment of disease activity in children with CPV particularly the most common forms of the disease that involve proteinase 3 ANCA. Key messages: - In children with chronic primary systemic vasculitis (CPV), classical measures of inflammation are not formally considered in scoring of disease activity. - Inflammatory markers-specifically S100A12 and neutrophil count-track preferentially with the most common forms of childhood CPV which affect small to medium sized vessels and involve anti neutrophil cytoplasmic antibodies (ANCA) against proteinase-3.

9.
Pediatr Rheumatol Online J ; 15(1): 61, 2017 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-28784150

RESUMO

BACKGROUND: Because pediatric antineutrophil cytoplasmic antibody-associated vasculitis is rare, management generally relies on adult data. We assessed treatment practices, uptake of existing clinical assessment tools, and interest in pediatric treatment protocols among rheumatologists caring for children with granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA). METHODS: A needs-assessment survey developed by an international working group of pediatric rheumatologists and two nephrologists was circulated internationally. Data were summarized with descriptive statistics. Pearson's chi-square tests were used in inferential univariate analyses. RESULTS: The 209 respondents from 36 countries had collectively seen ~1600 children with GPA/MPA; 144 had seen more than two in the preceding 5 years. Standardized and validated clinical assessment tools to score disease severity, activity, and damage were used by 59, 63, and 36%, respectively; barriers to use included lack of knowledge and limited perceived utility. Therapy varied significantly: use of rituximab rather than cyclophosphamide was more common among respondents from the USA (OR = 2.7 [1.3-5.5], p = 0.0190, n = 139), those with >5 years of independent practice experience (OR = 3.8 [1.3-12.5], p = 0.0279, n = 137), and those who had seen >10 children with GPA/MPA in their careers (OR = 4.39 [2.1-9.1], p = 0.0011, n = 133). Respondents who had treated >10 patients were also more likely to continue maintenance therapy for at least 24 months (OR = 3.0 [1.4-6.4], p = 0.0161, n = 127). Ninety six percent of respondents believed in a need for pediatric-specific treatment guidelines; 46% supported adaptation of adult guidelines while 69% favoured guidelines providing a limited range of treatment options to allow comparison of effectiveness through a registry. CONCLUSIONS: These data provide a rationale for developing pediatric-specific consensus treatment guidelines for GPA/MPA. While pediatric rheumatologist uptake of existing clinical tools has been limited, guideline uptake may be enhanced if outcomes of consensus-derived treatment options are evaluated within the framework of an international registry.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Conhecimentos, Atitudes e Prática em Saúde , Padrões de Prática Médica/estatística & dados numéricos , Criança , Guias como Assunto , Inquéritos Epidemiológicos , Humanos , Pediatria , Reumatologistas
10.
Clin Immunol ; 175: 143-146, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28043923

RESUMO

OBJECTIVES: Clinicians need to be aware of the growing list of defined monogenic etiologies of autoimmune diseases. This is particularly relevant when evaluating children, as these rare monogenic forms of autoimmunity tend to present very early in life. METHODS AND RESULTS: By harnessing the transformative power of next generation sequencing, we made the unifying diagnosis of RAS-associated autoimmune leukoproliferative disease (RALD), caused by the somatic gain-of-function p.G13C KRAS mutation, in a boy with the seemingly unrelated immune dysregulatory conditions of Rosai-Dorfman and systemic lupus erythematosus (SLE). CONCLUSIONS: This case expands our understanding of the clinical phenotypes associated with the extremely rare condition of RALD, and emphasizes the importance of always considering the possibility of a monogenic cause for autoimmunity, particularly when the disease manifestations begin early in life and do not follow a typical clinical course.


Assuntos
Autoimunidade/genética , Histiocitose Sinusal/genética , Lúpus Eritematoso Sistêmico/genética , Mutação/genética , Mutação/imunologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Adolescente , Autoimunidade/imunologia , Histiocitose Sinusal/imunologia , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Síndrome
11.
Front Immunol ; 8: 1828, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29375548

RESUMO

Chronic granulomatous disease (CGD) is caused by mutations in genes that encode the NADPH-oxidase and result in a failure of phagocytic cells to produce reactive oxygen species (ROS) via this enzyme system. Patients with CGD are highly susceptible to infections and often suffer from inflammatory disorders; the latter occurs in the absence of infection and correlates with the spontaneous production of inflammatory cytokines. This clinical feature suggests that NADPH-oxidase-derived ROS are not required for, or may even suppress, inflammatory processes. Experimental evidence, however, implies that ROS are in fact required for inflammatory cytokine production. By using a myeloid cell line devoid of a functional NADPH-oxidase and primary CGD cells, we analyzed intracellular oxidants, signs of oxidative stress, and inflammatory cytokine production. Herein, we demonstrate that phagocytes lacking a functional NADPH-oxidase, namely primary CGD phagocytes and a gp91phox-deficient cell line, display elevated levels of ROS derived from mitochondria. Accordingly, these cells, despite lacking the major source of cellular ROS, display clear signs of oxidative stress, including an induced expression of antioxidants and altered oxidation of cell surface thiols. These observed changes in redox state were not due to abnormalities in mitochondrial mass or membrane integrity. Finally, we demonstrate that increased mitochondrial ROS enhanced phosphorylation of ERK1/2, and induced production of IL8, findings that correlate with previous observations of increased MAPK activation and inflammatory cytokine production in CGD cells. Our data show that elevated baseline levels of mitochondria-derived oxidants lead to the counter-intuitive observation that CGD phagocytes are under oxidative stress and have enhanced MAPK signaling, which may contribute to the elevated basal production of inflammatory cytokines and the sterile inflammatory manifestations in CGD.

12.
Front Cell Neurosci ; 10: 286, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28018179

RESUMO

Immune cells display a high degree of phenotypic plasticity, which may facilitate their participation in both the progression and resolution of injury-induced inflammation. The purpose of this study was to investigate the temporal expression of genes associated with classical and alternative polarization phenotypes described for macrophages and to identify related cell populations in the brain following neonatal hypoxia-ischemia (HI). HI was induced in 9-day old mice and brain tissue was collected up to 7 days post-insult to investigate expression of genes associated with macrophage activation. Using cell-markers, CD86 (classic activation) and CD206 (alternative activation), we assessed temporal changes of CD11b+ cell populations in the brain and studied the protein expression of the immunomodulatory factor galectin-3 in these cells. HI induced a rapid regulation (6 h) of genes associated with both classical and alternative polarization phenotypes in the injured hemisphere. FACS analysis showed a marked increase in the number of CD11b+CD86+ cells at 24 h after HI (+3667%), which was coupled with a relative suppression of CD11b+CD206+ cells and cells that did not express neither CD86 nor CD206. The CD11b+CD206+ population was mixed with some cells also expressing CD86. Confocal microscopy confirmed that a subset of cells expressed both CD86 and CD206, particularly in injured gray and white matter. Protein concentration of galectin-3 was markedly increased mainly in the cell population lacking CD86 or CD206 in the injured hemisphere. These cells were predominantly resident microglia as very few galectin-3 positive cells co-localized with infiltrating myeloid cells in Lys-EGFP-ki mice after HI. In summary, HI was characterized by an early mixed gene response, but with a large expansion of mainly the CD86 positive population during the first day. However, the injured hemisphere also contained a subset of cells expressing both CD86 and CD206 and a large population that expressed neither activation marker CD86 nor CD206. Interestingly, these cells expressed the highest levels of galectin-3 and were found to be predominantly resident microglia. Galectin-3 is a protein involved in chemotaxis and macrophage polarization suggesting a novel role in cell infiltration and immunomodulation for this cell population after neonatal injury.

13.
Sci Rep ; 6: 36928, 2016 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-27869206

RESUMO

The extracellular matrix glycosaminoglycan, hyaluronan, has been described as a regulator of tissue inflammation, with hyaluronan fragments reported to stimulate innate immune cells. High molecular mass hyaluronan is normally present in tissues, but upon inflammation lower molecular mass fragments are generated. It is unclear if these hyaluronan fragments induce an inflammatory response or are a consequence of inflammation. In this study, mouse bone marrow derived macrophages and dendritic cells (DCs) were stimulated with various sizes of hyaluronan from different sources, fragmented hyaluronan, hyaluronidases and heavy chain modified-hyaluronan (HA-HC). Key pro-inflammatory molecules, tumour necrosis factor alpha, interleukin-1 beta, interleukin-12, CCL3, and the co-stimulatory molecules, CD40 and CD86 were measured. Only human umbilical cord hyaluronan, bovine testes and Streptomyces hyaluronlyticus hyaluronidase stimulated macrophages and DCs, however, these reagents were found to be contaminated with endotoxin, which was not fully removed by polymyxin B treatment. In contrast, pharmaceutical grade hyaluronan and hyaluronan fragments failed to stimulate in vitro-derived or ex vivo macrophages and DCs, and did not induce leukocyte recruitment after intratracheal instillation into mouse lungs. Hence, endotoxin-free pharmaceutical grade hyaluronan does not stimulate macrophages and DCs in our inflammatory models. These results emphasize the importance of ensuring hyaluronan preparations are endotoxin free.


Assuntos
Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Ácido Hialurônico/metabolismo , Interleucina-12/biossíntese , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Animais , Células Cultivadas , Ativação de Macrófagos , Camundongos
14.
J Emerg Manag ; 14(4): 259-68, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27575641

RESUMO

In the last several years, disasters-both manmade and natural-have taken their toll on college campuses. Extant research shows that college campuses have greatly increased their emergency management efforts. One area in which colleges and universities have made strides is emergency management communication. There has been some research examining emergency management communication across campuses, but there is still much to learn. This research fills a gap in this area by investigating the use of university Web sites to disseminate emergency management information to the university stakeholders. Data were gathered in 2007 and 2014 from the Web sites of public, 4-year universities in Indiana. The results show that universities are using the Internet to communicate emergency management information to their stakeholders. Among the most common categories of information available on the Web sites are links to other agencies, university response information, and threat levels. Implications for future research are discussed.


Assuntos
Comunicação , Emergências , Internet , Universidades , Indiana
15.
Front Immunol ; 6: 150, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25926830

RESUMO

Hyaluronan is made and extruded from cells to form a pericellular or extracellular matrix (ECM) and is present in virtually all tissues in the body. The size and form of hyaluronan present in tissues are indicative of a healthy or inflamed tissue, and the interactions of hyaluronan with immune cells can influence their response. Thus, in order to understand how inflammation is regulated, it is necessary to understand these interactions and their consequences. Although there is a large turnover of hyaluronan in our bodies, the large molecular mass form of hyaluronan predominates in healthy tissues. Upon tissue damage and/or infection, the ECM and hyaluronan are broken down and an inflammatory response ensues. As inflammation is resolved, the ECM is restored, and high molecular mass hyaluronan predominates again. Immune cells encounter hyaluronan in the tissues and lymphoid organs and respond differently to high and low molecular mass forms. Immune cells differ in their ability to bind hyaluronan and this can vary with the cell type and their activation state. For example, peritoneal macrophages do not bind soluble hyaluronan but can be induced to bind after exposure to inflammatory stimuli. Likewise, naïve T cells, which typically express low levels of the hyaluronan receptor, CD44, do not bind hyaluronan until they undergo antigen-stimulated T cell proliferation and upregulate CD44. Despite substantial knowledge of where and when immune cells bind hyaluronan, why immune cells bind hyaluronan remains a major outstanding question. Here, we review what is currently known about the interactions of hyaluronan with immune cells in both healthy and inflamed tissues and discuss how hyaluronan binding by immune cells influences the inflammatory response.

16.
Ann Neurol ; 75(3): 395-410, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24339166

RESUMO

OBJECTIVE: There is currently no pharmacological treatment that provides protection against brain injury in neonates. It is known that activation of an innate immune response is a key, contributing factor in perinatal brain injury; therefore, the neuroprotective therapeutic potential of innate defense regulator peptides (IDRs) was investigated. METHODS: The anti-inflammatory effects of 3 IDRs was measured in lipopolysaccharide (LPS)-activated murine microglia. IDRs were then assessed for their ability to confer neuroprotection in vivo when given 3 hours after neonatal brain injury in a clinically relevant model that combines an inflammatory challenge (LPS) with hypoxia-ischemia (HI). To gain insight into peptide-mediated effects on LPS-induced inflammation and neuroprotective mechanisms, global cerebral gene expression patterns were analyzed in pups that were treated with IDR-1018 either 4 hours before LPS or 3 hours after LPS+HI. RESULTS: IDR-1018 reduced inflammatory mediators produced by LPS-stimulated microglia cells in vitro and modulated LPS-induced neuroinflammation in vivo. When administered 3 hours after LPS+HI, IDR-1018 exerted effects on regulatory molecules of apoptotic (for, eg, Fadd and Tnfsf9) and inflammatory (for, eg, interleukin 1, tumor necrosis factor α, chemokines, and cell adhesion molecules) pathways and showed marked protection of both white and gray brain matter. INTERPRETATION: IDR-1018 suppresses proinflammatory mediators and cell injurious mechanisms in the developing brain, and postinsult treatment is efficacious in reducing LPS-induced hypoxic-ischemic brain damage. IDR-1018 is effective in the brain when given systemically, confers neuroprotection of both gray and white matter, and lacks significant effects on the brain under normal conditions. Thus, this peptide provides the features of a promising neuroprotective agent in newborns with brain injury.


Assuntos
Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Animais , Animais Recém-Nascidos , Anti-Inflamatórios não Esteroides/metabolismo , Anti-Inflamatórios não Esteroides/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/farmacocinética , Apoptose/efeitos dos fármacos , Lesões Encefálicas/metabolismo , Córtex Cerebral/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Hipóxia-Isquemia Encefálica/metabolismo , Inflamação/tratamento farmacológico , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Masculino , Camundongos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Fibras Nervosas Mielinizadas/efeitos dos fármacos , Fibras Nervosas Amielínicas/efeitos dos fármacos , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacocinética , Cultura Primária de Células , Distribuição Tecidual
17.
Arthritis Rheum ; 65(11): 2971-83, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23983059

RESUMO

OBJECTIVE: Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome is an autoinflammatory disease of unknown etiology that primarily affects preschool-aged children. PFAPA syndrome is characterized by recurrent attacks of fever and symptoms of inflammation consistent with the disease acronym. Since autoinflammatory diseases are, by definition, mediated by cells of the innate immune system, the aim of this study was to evaluate the functional features of neutrophils, the most abundant innate immune cell in the circulation, in children with PFAPA syndrome. METHODS: Blood polymorphonuclear leukocytes (PMNs), obtained from patients with PFAPA syndrome during both febrile and asymptomatic, afebrile phases of the disease, as well as from healthy children (afebrile controls) and children with fever and abdominal pain (febrile controls), were analyzed for 3 key neutrophil characteristics: 1) apoptosis (measured by annexin V/7-aminoactinomycin D staining), 2) production of reactive oxygen species (ROS) (measured by luminol/isoluminol-amplified chemiluminescence), and 3) priming status (measured as responsiveness to galectin-3 and up-regulation of CD11b). RESULTS: Compared to PMNs obtained from patients with PFAPA syndrome during an afebrile interval and those from febrile controls, PMNs obtained from patients during a PFAPA syndrome flare produced elevated levels of intracellular NADPH oxidase-derived ROS, had significantly diminished rates of spontaneous apoptosis, and displayed signatures of priming. In contrast, PMNs from afebrile patients with PFAPA syndrome had a significantly elevated rate of spontaneous apoptosis compared to PMNs from afebrile controls. CONCLUSION: These findings demonstrate that 3 key aspects of neutrophil innate immune function, namely, apoptosis, priming, and generation of an intracellular oxidative burst, are altered, most prominently during febrile attacks, in children with PFAPA syndrome.


Assuntos
Febre/metabolismo , Linfadenite/metabolismo , Neutrófilos/metabolismo , Faringite/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estomatite Aftosa/metabolismo , Proteínas da Fase Aguda/imunologia , Proteínas da Fase Aguda/metabolismo , Criança , Pré-Escolar , Feminino , Febre/imunologia , Humanos , Imunidade Inata/imunologia , Lactente , Linfadenite/imunologia , Masculino , Neutrófilos/imunologia , Faringite/imunologia , Estomatite Aftosa/imunologia
19.
J Biol Chem ; 286(22): 19179-90, 2011 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21471214

RESUMO

CD44 is a cell surface receptor for the extracellular matrix glycosaminoglycan hyaluronan and is involved in processes ranging from leukocyte recruitment to wound healing. In the immune system, the binding of hyaluronan to CD44 is tightly regulated, and exposure of human peripheral blood monocytes to inflammatory stimuli increases CD44 expression and induces hyaluronan binding. Here we sought to understand how mouse macrophages regulate hyaluronan binding upon inflammatory and anti-inflammatory stimuli. Mouse bone marrow-derived macrophages stimulated with tumor necrosis factor α or lipopolysaccharide and interferon-γ (LPS/IFNγ) induced hyaluronan binding by up-regulating CD44 and down-regulating chondroitin sulfation on CD44. Hyaluronan binding was induced to a lesser extent in interleukin-4 (IL-4)-activated macrophages despite increased CD44 expression, and this was attributable to increased chondroitin sulfation on CD44, as treatment with ß-d-xyloside to prevent chondroitin sulfate addition significantly enhanced hyaluronan binding. These changes in the chondroitin sulfation of CD44 were associated with changes in mRNA expression of two chondroitin sulfotransferases, CHST3 and CHST7, which were decreased in LPS/IFNγ-stimulated macrophages and increased in IL-4-stimulated macrophages. Thus, inflammatory and anti-inflammatory stimuli differentially regulate the chondroitin sulfation of CD44, which is a dynamic physiological regulator of hyaluronan binding by CD44 in mouse macrophages.


Assuntos
Sulfatos de Condroitina/metabolismo , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/metabolismo , Interleucina-4/metabolismo , Ativação de Macrófagos , Macrófagos/metabolismo , Animais , Linhagem Celular Tumoral , Sulfatos de Condroitina/imunologia , Regulação da Expressão Gênica , Humanos , Receptores de Hialuronatos/imunologia , Ácido Hialurônico/imunologia , Inflamação/imunologia , Inflamação/metabolismo , Interferon gama/imunologia , Interferon gama/metabolismo , Interferon gama/farmacologia , Interleucina-4/imunologia , Interleucina-4/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/imunologia , Camundongos , Camundongos Knockout , Sulfotransferases/imunologia , Sulfotransferases/metabolismo , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
20.
J Forensic Sci ; 56(3): 726-32, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21470222

RESUMO

With <100 pg of template DNA, routine short tandem repeat (STR) analysis often fails, resulting in no or partial profiles and increased stochastic effects. To overcome this, some have investigated preamplification methods that include the addition of proofreading enzymes to the PCR cocktail. This project sought to determine whether adding proofreading polymerases directly in the STR amplification mixture would improve the reaction when little template DNA is available. Platinum Taq High Fidelity and GeneAmp High Fidelity were tested in Profiler Plus™ STR reactions alone and in combination with AmpliTaq(®) Gold. All reactions included the additional step of a post-PCR purification step. With both pristine low template DNA and casework samples, the addition of these polymerases resulted in comparable or no improvement in the STR amplification signal. Further, stochastic effects and artifacts were observed equally across all enzyme conditions. Based on these studies, the addition of these proofreading enzymes to a multiplex STR amplification is not recommended for low template DNA work.


Assuntos
Impressões Digitais de DNA/métodos , DNA Polimerase Dirigida por DNA/metabolismo , DNA/análise , Sequências de Repetição em Tandem , Alelos , Sangue/metabolismo , Osso e Ossos/metabolismo , DNA/genética , Dermatoglifia , Eletroforese Capilar , Humanos , Incisivo/metabolismo , Reação em Cadeia da Polimerase , Aço
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA