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1.
J Cell Biochem ; 121(12): 4945-4958, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32692864

RESUMO

Recently, we detected a novel biomarker in human saliva called calcium-binding protein, spermatid-associated 1 (CABS1). CABS1 protein had previously been described only in testis, and little was known of its characteristics other than it was considered a structurally disordered protein. Levels of human CABS1 (hCABS1) in saliva correlate with stress, whereas smaller sized forms of hCABS1 in saliva are associated with resilience to stress. Interestingly, hCABS1 also has an anti-inflammatory peptide sequence near its carboxyl terminus, similar to that of a rat prohormone, submandibular rat 1. We performed phylogenetic and sequence analysis of hCABS1. We found that from 72 CABS1 sequences currently annotated in the National Center for Biotechnology Information protein database, only 14 contain the anti-inflammatory domain "TxIFELL," all of which are primates. We performed structural unfoldability analysis using PONDER and FoldIndex and discovered three domains that are highly disordered. Predictions of three-dimensional structure of hCABS1 using RaptorX, IonCom, and I-TASSER software agreed with these findings. Predicted neutrophil elastase cleavage density also correlated with hCABS1 regions of high structural disorder. Ligand binding prediction identified Ca2+ , Mg2+ , Zn2+ , leucine, and thiamine pyrophosphate, a pattern observed in enzymes associated with energy metabolism and mitochondrial localization. These new observations on hCABS1 raise intriguing questions about the interconnection between the autonomic nervous system, stress, and the immune system. However, the precise molecular mechanisms involved in the complex biology of hCABS1 remain unclear. We provide a detailed in silico analysis of relevant aspects of the structure and function of hCABS1 and postulate extracellular and intracellular roles.

2.
SAGE Open Nurs ; 6: 2377960820925984, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33415281

RESUMO

INTRODUCTION: An estimated 8.1% of Canadians adults have asthma. While there are challenges associated with the use of objective measurement of lung function in the diagnosis of asthma, we are uncertain of the barriers that impact the use of objective measures, and have limited understanding of the challenges experienced by primary care providers in diagnosis of asthma. The objectives of this quality improvement initiative were to identify primary care providers' methods of diagnosing asthma and to identify challenges with diagnosis. METHODS: An online survey was disseminated using a snowball methodology. SETTING: Primary care practices in Alberta, Canada. PARTICIPANTS: A total of 84 primary care providers completed the survey. MAIN OUTCOME MEASURES: Participants were asked their ideal and sufficient methods for diagnosing asthma and to identify challenges in their practice related to asthma diagnosis. RESULTS: They identified full pulmonary function testing (54%), pre- and postbronchodilator spirometry (54%), complete history and physical (42%), peak flow measurement overtime (26%), pulmonary consult (26%), and trial of asthma medication(s) (23%), as ideal methods of diagnosing asthma. The most significant barriers to diagnosis included episodic care-care provided typically during times of worsening symptoms without ongoing preventative/maintenance care (55%), patient follow-up (44%), conflict between clinical impression and pulmonary function results (43%), patient already on asthma medications (43%), and interpreting spirometry/pulmonary function results (39%). CONCLUSION: The results of this survey indicate that the majority of primary care providers would choose full pulmonary function testing or pre- and postbronchodilator spirometry as the ideal methods of diagnosing asthma. However, barriers related to the nature of asthma care, patient factors, and challenges with diagnostic testing create challenges. This study also highlights that primary care providers have adapted to challenges in leveraging objective measurement and may rely upon other methods for diagnosis such as trials of medications.

3.
J Transl Med ; 15(1): 53, 2017 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-28253888

RESUMO

BACKGROUND: Although discovery research has identified the importance of dozens of pro- and anti-inflammatory immune mediators in the pathogenesis, maintenance, exacerbation and resolution of inflammatory diseases, most human cohort studies have incorporated few or no immunological intermediate phenotypes in their analyses. Significant hindrances have been (1) the limited panel of biomarkers known to be readily detected in healthy human populations and (2) the stability, hence utility, of such biomarkers to repeated analysis. METHODS: The frequency and stability of 14 plasma biomarkers linked to in vivo immune regulation of allergic and autoimmune inflammatory disorders was determined in 140 healthy pediatric and adult participants. The impact of initial and multiple subsequent freeze/thaw cycles on pro-inflammatory (CCL2, CXCL10, IL-18, TNFα, IL-6), anti-inflammatory (IL-10, sTNF-RII, IL-1Ra), acute phase proteins (CRP, PTX3) and other biomarkers (sST2, IL-1RAcP) was subsequently quantified. RESULTS: Multiple biomarkers capable of providing an innate immune signature of inflammation were readily detected directly ex vivo in healthy individuals. These biomarker levels were unaffected when comparing paired data sets from freshly obtained, never frozen plasma or serum and matched aliquots despite extensive freeze/thaw cycles. Neither age nor sex affected stability. Similarly, no quantitative differences were found following repetitive analysis of inflammatory biomarkers in culture samples obtained following in vitro stimulation with TLR and RLR ligands. CONCLUSIONS: A broad panel of in vivo and ex vivo cytokine, chemokine and acute phase protein biomarkers that have been linked to human chronic inflammatory disorders are readily detected in vivo and remain stable for analysis despite multiple freeze thaw cycles. These data provide the foundation and confidence for large scale analyses of panels of inflammatory biomarkers to provide better understanding of immunological mechanisms underlying health versus disease.


Assuntos
Anti-Inflamatórios/sangue , Biomarcadores/sangue , Mediadores da Inflamação/sangue , Células Cultivadas , Estudos de Coortes , Feminino , Congelamento , Humanos , Masculino , Soro/metabolismo , Doadores de Tecidos
4.
Paediatr Perinat Epidemiol ; 29(1): 84-92, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25405552

RESUMO

BACKGROUND: It is hypothesised that complex interactions between genetic and environmental factors give rise to allergy and asthma in childhood. The Canadian Healthy Infant Longitudinal Development (CHILD) study was designed to explore these factors. METHODS: CHILD is a longitudinal, general population birth cohort study following infants from mid-pregnancy to age 5 years. Over this time period, biological samples, questionnaires, clinical measures and environmental data are collected. RESULTS: A total of 3624 families have been recruited, and many thousands of samples and questionnaires have been collected, annotated, and archived. This report outlines the rationale and methodology for collecting and storing diverse biological samples from parents and children in this study, and the mechanisms for their release for analyses. CONCLUSIONS: The CHILD sample and data repository is a tremendous current and future resource and will provide a wealth of information not only informing studies of asthma and allergy, but also potentially in many other aspects of health relevant for Canadian infants and children.


Assuntos
Asma/epidemiologia , Bancos de Espécimes Biológicos/organização & administração , Hipersensibilidade/epidemiologia , Canadá/epidemiologia , Proteção da Criança , Pré-Escolar , Feminino , Humanos , Lactente , Bem-Estar do Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Gravidez , Estudos Prospectivos , Inquéritos e Questionários
5.
Mucosal Immunol ; 3(2): 111-28, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20043008

RESUMO

Mast cells are classically viewed as effector cells of IgE-mediated allergic diseases. However, over the last decade our understanding has been enriched about their roles in host defense, innate and adaptive immune responses, and in homeostatic responses, angiogenesis, wound healing, tissue remodeling, and immunoregulation. Despite impressive progress, there are large gaps in our understanding of their phenotypic heterogeneity, regulatory mechanisms involved, and functional significance. This review summarizes our knowledge of mast cells in innate and acquired immunity, allergic inflammation and tissue homeostasis, as well as some of the regulatory mechanisms that control mast cell development, phenotypic determination, and function, particularly in the context of mucosal surfaces.


Assuntos
Imunidade Adaptativa , Imunidade Inata , Mastócitos/imunologia , Animais , Modelos Animais de Doenças , Humanos , Mastócitos/classificação
6.
Am J Physiol Cell Physiol ; 296(3): C514-24, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19109528

RESUMO

The autonomic nervous system regulates the secretion of bioactive proteins and peptides from salivary glands that can be important in systemic physiological responses. The prohormone submandibular rat-1, which is highly expressed in rat submandibular glands, can be cleaved to produce polypeptides with analgesic and anti-inflammatory activities. Human genes related to submandibular rat-1 have conserved biological functions and are potentially important in pain suppression, erectile function, and inflammation. In this study we describe the differential expression and posttranslational modification of submandibular rat-1 protein in salivary glands, the urogenital tract, lung, blood, and saliva in male Sprague-Dawley and Brown Norway rats. Submandibular rat-1 protein is secreted into saliva after the administration of beta-adrenergic or cholinergic agonists. Removal of the sympathetic ganglion that innervates the salivary glands results in increased levels of submandibular rat-1 protein in salivary glands. The secretion of submandibular rat-1 in response to physiological stress may provide a large pool of submandibular rat-1-derived peptide products that can promote analgesia and decrease inflammation locally and systemically. This pathway may be conserved among mammals and may constitute an important anti-inflammatory and analgesic response to stress.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Precursores de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Glândulas Salivares/inervação , Glândulas Salivares/metabolismo , Proteínas e Peptídeos Salivares/metabolismo , Salivação , Agonistas Adrenérgicos beta/farmacologia , Sequência de Aminoácidos , Animais , Anticorpos , Sistema Nervoso Autônomo/efeitos dos fármacos , Sistema Nervoso Autônomo/cirurgia , Agonistas Colinérgicos/farmacologia , Feminino , Ganglionectomia , Glicosilação , Inflamação/fisiopatologia , Inflamação/prevenção & controle , Pulmão/metabolismo , Masculino , Dados de Sequência Molecular , Glândula Parótida/metabolismo , Precursores de Proteínas/sangue , Precursores de Proteínas/genética , Precursores de Proteínas/imunologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Coelhos , Ratos , Ratos Endogâmicos BN , Ratos Sprague-Dawley , Glândulas Salivares/efeitos dos fármacos , Proteínas e Peptídeos Salivares/sangue , Proteínas e Peptídeos Salivares/genética , Proteínas e Peptídeos Salivares/imunologia , Salivação/efeitos dos fármacos , Fatores de Tempo , Sistema Urogenital/metabolismo
7.
Scand J Immunol ; 67(2): 121-32, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18201367

RESUMO

Macrophage migration inhibitory factor (MIF) is found in immune-privileged sites and inhibits cytotoxicity mediated by CD3-ve lymphokine-activated killer cells (LAK). The mechanism by which MIF attenuates LAK cytotoxicity is unknown. We provide evidence that MIF has a major histocompatibility complex (MHC) class I-like motif. A monoclonal antibody (OX18) that binds a conserved region of rat MHC class I proteins binds native MIF. Anti-MIF polyclonal antibodies bind MHC class I. Epitope mapping suggests OX18 binds a loop of MHC class I bound by several receptors for MHC class I. A sequence (PRPEG) within the proposed OX18-binding site on MHC class I exists with a short insertion in MIF. OX18 does not bind MIF that is denatured by SDS-PAGE. This suggests the OX18 epitope is dependent on higher order structure in MIF. Interestingly, MIF inhibits binding of tetramers of MHC class I (H2D(b)) to LAK cells, suggesting it may bind to receptors for MHC class I. MIF may be an example where small regions of MHC class I are used by endogenous and viral proteins to control cytotoxicity mediated by immune cells.


Assuntos
Antígenos de Histocompatibilidade Classe I/imunologia , Oxirredutases Intramoleculares/imunologia , Células Matadoras Ativadas por Linfocina/imunologia , Fatores Inibidores da Migração de Macrófagos/imunologia , Motivos de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Western Blotting , Mapeamento de Epitopos , Humanos , Oxirredutases Intramoleculares/isolamento & purificação , Fatores Inibidores da Migração de Macrófagos/isolamento & purificação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Dados de Sequência Molecular , Ratos
8.
Immunology ; 123(2): 209-17, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17662042

RESUMO

Mast cells (MCs) are critical immune effector cells that release cytokines and chemokines involved in both homeostasis and disease. Interferon-gamma (IFN-gamma) is a pleiotropic cytokine that regulates multiple cellular activities. IFN-gamma modulates rodent MC responsiveness via production of nitric oxide (NO), although the effects in human MC populations is unknown. We sought to investigate the effects of IFN-gamma on expression of the chemokines interleukin-8 (IL-8) and CCL1 (I-309) in a human mast cell line (HMC1) and to determine the underlying regulatory mechanism. Nitric oxide synthase (NOS), IL-8 and CCL1 expression was determined using real-time polymerase chain reaction (PCR). NOS protein expression was analysed using western blot. NOS activity was determined using the citrulline assay. IL-8 and CCL1 release was measured by specific enzyme-linked immunosorbent assay (ELISA). IFN-gamma inhibited phorbol 12-myristate 13-acetate (PMA)-induced release of IL-8 and CCL1 (by 47 and 38%). Real-time PCR analysis of IFN-gamma-treated HMC1 showed a significant (P < 0.05) time-dependent increase in NOS1 and NOS3 mRNA. NOS3 protein was significantly increased at 18 hr, which correlated with a significant (P < 0.05) increase in constitutive NOS (cNOS) activity. IFN-gamma-induced inhibition of chemokine expression and release was NO dependent, as treatment with the NOS inhibitor N(G)-nitro-l-arginine methyl ester (l-NAME) reduced the IFN-gamma inhibitory effect on IL-8 and CCL1 mRNA expression. NO donors mimicked the IFN-gamma effect. IFN-gamma inhibited PMA-induced cAMP response element binding protein (CREB) phosphorylation and DNA-binding activity. Our observations indicate for the first time that IFN-gamma enhances endogenous NO formation through NOS3 activity, and that NO regulates the transcription and release of IL-8 and CCL1 in a human MC line.


Assuntos
Quimiocinas/metabolismo , Interferon gama/imunologia , Mastócitos/imunologia , Óxido Nítrico/imunologia , Linhagem Celular , Quimiocina CCL1/biossíntese , Quimiocina CCL1/genética , Relação Dose-Resposta Imunológica , Regulação da Expressão Gênica/imunologia , Humanos , Interleucina-8/biossíntese , Interleucina-8/genética , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase/genética , RNA Mensageiro/genética , Transdução de Sinais/imunologia , Fatores de Transcrição/metabolismo
9.
Can Respir J ; 13(1): 23-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16470250

RESUMO

BACKGROUND: Most children with asthma should be able to achieve acceptable control. However, are there differences between those with acceptable and poor control, and if so, how can health care approaches be modified accordingly? OBJECTIVE: To examine the characteristics of elementary school children aged five to 13 years with acceptable and poor levels of asthma control. METHODS: The present cross-sectional study of children with asthma used five indicators of control, as outlined by the Canadian Asthma Consensus Report, to categorize acceptable and poor asthma control. RESULTS: Of 153 children, 115 (75%) were rated as having poorly controlled asthma. Of those with poor control, 65 (64%) children were currently using inhaled corticosteroids, and 65% of those reported using inhaled corticosteroids daily versus as needed. Fifty-one per cent of the children with poorly controlled asthma had exposure to tobacco smoke, whereas 79% of the children with asthma under acceptable control were from households with no smokers (P=0.002). The poor control group also had significantly worse parental perceptions of the psychosocial impact of asthma on their child. No significant difference was found in the percentage of those who had written action plans in the poor control group (28%) compared with the acceptable control group (26%), and similar percentages in each group stated that they used the plans. CONCLUSIONS: Despite the high use of inhaled corticosteroids, the majority of children had poorly controlled asthma. The poor control group had more exposure to tobacco smoke and a worse psychosocial impact due to asthma. Few children had past asthma education and action plans, suggesting that there is a need to improve access to and tools for education.


Assuntos
Asma/terapia , Administração por Inalação , Adolescente , Corticosteroides/administração & dosagem , Agonistas Adrenérgicos beta/administração & dosagem , Asma/fisiopatologia , Asma/psicologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Masculino , Educação de Pacientes como Assunto , Autocuidado/métodos , Poluição por Fumaça de Tabaco/efeitos adversos
10.
Curr Mol Med ; 5(6): 573-89, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16178768

RESUMO

Mast cells (MC) are major effector cells of IgE-mediated allergic inflammation. However, it has become increasingly clear that they also play important roles in a diversity of physiological and pathological processes. Recent advances have focused on the importance of MC in both innate and adaptive immune responses and have fostered studies of MC beyond the myopic focus on allergic reactions. MC possess a great variety of surface receptors and may be activated by inflammatory mediators, immunoglobulins, proteases, hormones, neuropeptides and bacterial products. Following activation they produce a plethora of pro-inflammatory mediators and may participate in inflammatory reactions in many organs. This review focuses on the role of MC in inflammatory reactions in mucosal surfaces with particular emphasis on their role in asthma and gastrointestinal inflammatory conditions.


Assuntos
Mastócitos/imunologia , Mucosa/imunologia , Apoptose/imunologia , Asma/imunologia , Adesão Celular/imunologia , Degranulação Celular , Movimento Celular/imunologia , Cistite Intersticial/complicações , Cistite Intersticial/imunologia , Hipersensibilidade Alimentar/imunologia , Gastrite/imunologia , Humanos , Imunidade Inata , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Mastócitos/metabolismo , Mastócitos/fisiologia , Modelos Biológicos , Mucosa/metabolismo
11.
Mem Inst Oswaldo Cruz ; 100 Suppl 1: 11-4, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15962092

RESUMO

Mast cells (MC) are important in the numerous physiological processes of homeostasis and disease. Most notably, MC are critical effectors in the development and exacerbation of allergic disorders. Nitric oxide (NO) is a diatomic radical produced by nitric oxide synthase (NOS), and has pluripotent cell signaling and cytotoxic properties. NO can influence many MC functions. Recent evidence shows the source of this NO can be from the mast cell itself. Governing the production of this endogenous NO, through alterations in the expression of tetrahydrobiopterin (BH4), a NOS cofactor, has stabilizing effects on MC degranulation. Furthermore, NO regulates the synthesis and secretion of de novo generated mediators, including leukotrienes and chemokines. These novel observations add to the growing body of knowledge surrounding the role of NO in the MC.


Assuntos
Mastócitos/fisiologia , Óxido Nítrico/fisiologia , Animais , Biopterinas/análogos & derivados , Biopterinas/metabolismo , Degranulação Celular/fisiologia , Células Cultivadas , Quimiocinas/fisiologia , Humanos , Leucotrienos/fisiologia , Masculino , Mastócitos/enzimologia , Camundongos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Fenótipo , Ratos , Ratos Sprague-Dawley
12.
Mem. Inst. Oswaldo Cruz ; 100(supl.1): 11-14, Mar. 2005. tab
Artigo em Inglês | LILACS | ID: lil-402169

RESUMO

Mast cells (MC) are important in the numerous physiological processes of homeostasis and disease. Most notably, MC are critical effectors in the development and exacerbation of allergic disorders. Nitric oxide (NO) is a diatomic radical produced by nitric oxide synthase (NOS), and has pluripotent cell signaling and cytotoxic properties. NO can influence many MC functions. Recent evidence shows the source of this NO can be from the mast cell itself. Governing the production of this endogenous NO, through alterations in the expression of tetrahydrobiopterin (BH4), a NOS cofactor, has stabilizing effects on MC degranulation. Furthermore, NO regulates the synthesis and secretion of de novo generated mediators, including leukotrienes and chemokines. These novel observations add to the growing body of knowledge surrounding the role of NO in the MC.


Assuntos
Animais , Humanos , Masculino , Camundongos , Ratos , Mastócitos/fisiologia , Óxido Nítrico/fisiologia , Biopterinas/análogos & derivados , Biopterinas/metabolismo , Células Cultivadas , Degranulação Celular/fisiologia , Quimiocinas/fisiologia , Leucotrienos/fisiologia , Mastócitos/enzimologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Fenótipo , Ratos Sprague-Dawley
13.
J Asthma ; 40(5): 523-33, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14529102

RESUMO

To evaluate the effectiveness of a comprehensive asthma management education program for 7- to 12-year-old children with asthma, entitled Roaring Adventures of Puff (RAP), 18 elementary schools in Edmonton were randomized to intervention and control groups. Participating in the program were 76 students with asthma in the intervention schools and 86 in the control schools. Children in the intervention schools had statistically significant improvements in unscheduled doctor visits, missed school days, moderate-to-severe parent rating of severity, severity of shortness of breath, limitations in the kind of play, and correct use of medications. Unscheduled doctor visits and missed school days were the only significant improvements in the control group; however, improvements were about half that of the intervention group. The results showed that a comprehensive, school-based asthma education program is feasible and improves outcomes.


Assuntos
Asma/terapia , Educação em Saúde/métodos , Serviços de Saúde Escolar/organização & administração , Adolescente , Canadá , Criança , Pré-Escolar , Gerenciamento Clínico , Feminino , Comportamentos Relacionados com a Saúde , Nível de Saúde , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde , Qualidade de Vida , Resultado do Tratamento
14.
Inflamm Res ; 51(9): 451-6, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12365718

RESUMO

OBJECTIVE AND DESIGN: The expression of specific Cl- channels in mast cells (MC) is poorly understood. Because the largest and most ubiquitously expressed family of Cl- channels is the ClC, we studied MC mRNA and protein expression for members of the ClC family. METHODS: Specific primers were designed to ClC-1 to -7 and reverse-transcriptase polymerase chain reaction (RT-PCR) was performed on RNA from highly purified rat peritoneal mast cells (PMC) and the rat cultured mast cell line (RCMC). Protein expression of ClC-2, -3 and -7 chloride channels in PMC and RCMC was studied using western blotting. RESULTS: RT-PCR showed that RCMC expressed mRNA for the Cl- channels (ClC)-2, -3, -4, -5 and -7, while PMC expressed ClC-7. Using Western Blotting, we found protein expression of ClC-2 and ClC-7, but not ClC-3, in RCMC, whereas in PMC neither of these proteins could be detected. CONCLUSION: These results indicate that MC express several members of the ClC family and that these Cl- channels might be important in MC functions.


Assuntos
Canais de Cloreto/metabolismo , Mastócitos/metabolismo , Animais , Células Cultivadas , Canais de Cloreto/genética , Expressão Gênica , Masculino , Mastócitos/fisiologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
15.
J Leukoc Biol ; 71(4): 618-24, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11927648

RESUMO

Nitric oxide (NO) is a potent mediator synthesized by a variety of cells involved in inflammatory reactions. We investigated the expression of NO synthase (NOS) in rat peritoneal mast cells (PMC). Small amounts of eNOS mRNA were detected basally, whereas neither mRNA for iNOS nor nNOS was detected in unstimulated PMC. Following stimulation by antigen, interferon-gamma (IFN-gamma), or anti-CD8 antibody, PMC up-regulated iNOS mRNA expression. In situ RT-PCR confirmed that iNOS mRNA originated from PMC. Production of iNOS protein was confirmed in stimulated PMC by immunohistochemistry. Upon stimulation with antigen, IFN-gamma, or anti-CD8, nitrite production was increased significantly (8.4+/-0.6, 7.6+/-0.9, and 6.6+/-0.9 microM/2x10(5) cells/48 h NO2-, respectively; P<0.01), whereas unstimulated PMC released 2.1 +/- 0.3 microM/2 x 10(5) cells/48 h NO2-. These findings demonstrate that in vivo-derived PMC transcribe and translate mRNA for NOS and produce NO.


Assuntos
Mastócitos/metabolismo , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico/biossíntese , Animais , Interferon gama/farmacologia , Masculino , Óxido Nítrico Sintase/análise , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
J Leukoc Biol ; 71(1): 54-64, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11781380

RESUMO

Mast cell activation requires Cl(-) flux, which maintains the driving force for entry of extracellular calcium and initiates release of mediators such as histamine. However, chloride channel expression in mast cells has been poorly understood. For the first time, reverse transcriptase-polymerase chain reaction shows that rat-cultured mast cells (RCMC) and peritoneal mast cells (PMC) contain mRNA for the cystic fibrosis transmembrane conductance regulator (CFTR), an important chloride channel. Immunostaining with an anti-CFTR antibody indicates expression of CFTR in PMC and RCMC. Mast cell CFTR is a functional Cl(-) channel because it is capable of mediating Cl(-) flux in response to elevated cAMP. An inhibitor of CFTR-dependent Cl(-) flux, diphenylamine-2-carboxylate down-regulates mast cell mediator release. These results show that rat mast cells express a functional CFTR, which might be important in mediator release.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/biossíntese , Mastócitos/metabolismo , Animais , Sequência de Bases , Células Cultivadas , Cloretos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Transporte de Íons , Masculino , Dados de Sequência Molecular , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley
17.
J Immunol ; 167(10): 5935-9, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11698471

RESUMO

We recently reported a novel CD8 molecule on rat alveolar macrophages and peritoneal mast cells (PMC). However, little is known about the regulation of CD8 expression and function on these cells. We investigated the regulation of CD8 expression on PMC by NO, because NO can regulate inflammatory responses and also because anti-CD8 Ab stimulates inducible NO synthase and NO production by PMC and alveolar macrophages. Ligation of CD8alpha on PMC with Ab (OX8) induced CD8alpha mRNA expression after 3-6 h, and flow cytometry demonstrated that OX8 treatment increased CD8alpha protein expression compared with PMC treated with isotype control IgG1. To test whether NO mediates the up-regulation of CD8alpha, we used the NO donor S-nitrosoglutathione (500 microM) and NO synthase inhibitors (N(G)-monomethyl-L-arginine and N(G)-nitro-L-arginine methyl ester; 100 microM). S-nitrosoglutathione up-regulated both mRNA and protein expression of CD8alpha in PMC compared with that in sham-treated cells, while NO synthase inhibitors down-regulated OX8 Ab-induced CD8alpha expression. To investigate how NO regulates CD8 expression on PMC, we examined the cGMP-dependent pathway using 8-bromo-cGMP (2 mM) and the guanylate cyclase inhibitor, 1H-oxadiazoloquinoxalin-1-one (20 microM). 8-Bromo-cGMP up-regulated CD8 expression, whereas 1H-oxadiazoloquinoxalin-1-one down-regulated its expression. Thus, ligation of CD8 up-regulates CD8 expression on PMC, a response mediated at least in part by NO through a cGMP-dependent pathway. The significance of this up-regulation of CD8alpha on mast cells (MC) is unclear, but since ligation of CD8 on MC with OX8 Ab can alter gene expression and mediator secretion, up-regulation of CD8 may enhance the MC response to natural ligation of this novel form of CD8.


Assuntos
Antígenos CD8/biossíntese , Mastócitos/imunologia , Óxido Nítrico/fisiologia , Regulação para Cima , Animais , Anticorpos/farmacologia , Antígenos CD8/genética , Antígenos CD8/imunologia , Células Cultivadas , GMP Cíclico/fisiologia , Inibidores Enzimáticos/farmacologia , Mastócitos/efeitos dos fármacos , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Peritônio/imunologia , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , S-Nitrosoglutationa/farmacologia , Ativação Transcricional , ômega-N-Metilarginina/farmacologia
18.
Int Immunopharmacol ; 1(8): 1525-41, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11515817

RESUMO

Mast cells are involved in numerous activities ranging from control of the vasculature, to tissue injury and repair, allergic inflammation and host defences. They synthesize and secrete a variety of mediators, activating and modulating the functions of nearby cells and initiating complex physiological changes. Interestingly, NO produced by mast cells and/or other cells in the microenvironment appears to regulate these diverse roles. This review outlines some of the pathways central to the production of NO by mast cells and identifies many of the tightly controlled regulatory mechanisms involved. Several cofactors and regulatory elements are involved in NO production, and these act at transcriptional and post-translational sites. Their involvement in NO production will be outlined and the possibility that these pathways are critically important in mast cell functions will be discussed. The effects of NO on mast cell functions such as adhesion, activation and mediator secretion will be examined with a focus on molecular mechanisms by which NO modifies intracellular signalling pathways dependent or independent of cGMP and soluble guanylate cyclase. The possibility that NO regulates mast cell function through effects on selected ion channels will be discussed. Metabolic products of NO including peroxynitrite and other reactive species may be the critical elements that affect the actions of NO on mast cell functions. Further understanding of the actions of NO on mast cell activities may uncover novel strategies to modulate inflammatory conditions.


Assuntos
Mastócitos/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/fisiologia , Animais , Humanos , Mastócitos/imunologia
19.
Int Arch Allergy Immunol ; 124(1-3): 201-4, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11306968

RESUMO

BACKGROUND: The C-terminal of the prohormone submandibular rat 1 protein (SMR-1) contains several small peptides that reduce the severity of allergic inflammation and septic shock, and are part of the cervical sympathetic trunk-submandibular gland (SMG) axis of neuroendocrine immunology. These peptides include the heptapeptide, submandibular gland peptide-T and the tripeptide FEG. The D-isomeric form of this tripeptide, feG, which is active when administered orally, reduces LPS-provoked leukocyte rolling on mesenteric venules and influx of inflammatory cells into the peritoneum and intestinal muscle. METHODS: To investigate the mechanism of action of these peptides, the influx of inflammatory molecules into the airways, and several properties of human neutrophils were examined. RESULTS: Oral feG (1 mg/kg) inhibited the influx of inflammatory cells into the airways lumen of allergen challenged, sensitized Brown Norway rats. This inhibition occurred whether feG was given 30 min prior to 6 h post allergen challenge. Moreover, feG in picomolar to nanomolar concentrations inhibited PAF elicited chemotaxis by 30-40%, but the peptides did not affect superoxide production or phagocytosis by neutrophils. feG reduced PAF-stimulated expression of CD11b. CONCLUSIONS: feG may exert its anti-inflammatory effects by modulating the expression and functions of beta(2) integrins. The CST-SMG axis may be a major neuroendocrine pathway that modulates allergic asthma and other inflammatory responses.


Assuntos
Asma/imunologia , Neuroimunomodulação , Oligopeptídeos/farmacologia , Precursores de Proteínas/farmacologia , Proteínas e Peptídeos Salivares/farmacologia , Alérgenos/imunologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Células Cultivadas , Quimiotaxia de Leucócito , Antígeno de Macrófago 1/metabolismo , Neutrófilos/imunologia , Fator de Ativação de Plaquetas/farmacologia , Ratos
20.
J Allergy Clin Immunol ; 107(4): 679-85, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11295658

RESUMO

BACKGROUND: Epithelium is considered an active participant in allergic inflammation. Proteinase-activated receptor (PAR) 2 is expressed in a variety of cell types, including epithelial cells, and has been implicated in inflammation. OBJECTIVE: PAR-2-mediated activation of airway epithelial cells induces the release of mediators that could promote eosinophil survival and mediate eosinophil recruitment. METHODS: PAR-2-activating peptides were used to activate the human airway epithelial cell line A549, as well as primary cultures of small airway epithelial cells (SAECs). Human peripheral blood eosinophils were cultured in the presence or absence of epithelial cell supernatants. Survival was assessed by using an Annexin V apoptosis detection kit. GM-CSF and eotaxin were measured by using ELISA. RESULTS: Eosinophils undergo apoptosis in the absence of growth factors. Supernatants from PAR-2-activated A549 epithelial cells increased eosinophil survival. Supernatants from resting SAECs also increased eosinophil survival, but supernatants from PAR-2-activated SAECs showed a greater effect. The effect of PAR-2-activated epithelial cell supernatants on eosinophil survival was completely inhibited by a neutralizing anti-GM-CSF antibody but not an anti-IL-5 antibody. Resting A549 cells did not release any detectable GM-CSF, whereas PAR-2-activated cells released 35 pg/10(6) cells. Resting SAECs released 754.3 pg/10(6) cells of GM-CSF, which was further increased to 1360.5 pg/10(6) cells after PAR-2-mediated activation. Budesonide inhibited this PAR-2 effect. PAR-2-activated epithelial cells also released eotaxin. CONCLUSION: PAR-2-mediated activation of airway epithelial cells induced release of GM-CSF, which promoted eosinophil survival and activation. It also induced release of eotaxin, which could mediate eosinophil recruitment to the airways.


Assuntos
Quimiocinas CC , Eosinófilos/fisiologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Pulmão/metabolismo , Receptores de Trombina/fisiologia , Linhagem Celular , Quimiocina CCL11 , Citocinas/metabolismo , Células Epiteliais/metabolismo , Humanos , Receptor PAR-2
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