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1.
J Clin Lab Anal ; 36(1): e24124, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34850456

RESUMO

OBJECTIVE: Thyroid hormone autoantibody (THAb) is a common antibody in autoimmune disease and can interfere with the detection of thyroid hormone (TH). There was no research reporting the prevalence of THAb in Chinese and the rate of THAb interfering with TH detection. METHODS: We collected 114 patients with autoimmune thyroid disease (AITD) (Hashimoto's thyroiditis, 57 cases; Graves' disease, 57 cases), 106 patients with nonthyroid autoimmune diseases (NTAID), and 120 healthy subjects. According to the presence or absence of thyroid antibodies, patients with NTAID were divided into two groups: NTAID-AITD and NTAID groups. Radioimmunoprecipitation technique was used to detect THAb in all subjects. TH was detected on Abbot and Roche platforms in patients with positive THAb. RESULTS: The prevalence of THAb was 22.8% in Hashimoto's thyroiditis and 45.6% in Graves' disease. The prevalence of THAb in AITD group was lower than that in NTAID or NTAID-AITD groups (34.2% vs. 61.5%, p = 0.014; 34.2% vs. 71.3%, p < 0.01). Among total 98 patients with positive THAb, TH levels of 9 patients were falsely elevated (9.18%). CONCLUSION: The prevalence of THAb in AITD patients was lower than that in NTAID patients. Although THAb had a high frequency in various autoimmune diseases, the prevalence of THAb interfering with TH detection was only 9.18%.


Assuntos
Autoanticorpos/sangue , Doença de Graves , Doença de Hashimoto , Hormônios Tireóideos/imunologia , Adulto , Feminino , Doença de Graves/sangue , Doença de Graves/epidemiologia , Doença de Graves/imunologia , Doença de Hashimoto/sangue , Doença de Hashimoto/epidemiologia , Doença de Hashimoto/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Ensaio de Radioimunoprecipitação/normas , Hormônios Tireóideos/sangue
2.
Int J Med Sci ; 17(9): 1235-1245, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547319

RESUMO

Diabetes-mediated hyperglycemia is a major risk factor for renal fibrosis, resulting in the development of chronic kidney diseases. To address this issue, the effect of melatonin, which has an antioxidative potential, on renal fibrosis in human renal proximal tubule epithelial cells under high glucose conditions was investigated. Under high glucose conditions, the generation of reactive oxygen species was drastically increased in human renal proximal tubule epithelial cells, which lead to the inhibition of cell proliferation, enlargement of cell size, reduction of cell survival, and suppression of antioxidant enzyme activities. High glucose also increased the expression of transforming growth factor-ß, leading to an increase in Smad2 phosphorylation. These fibrotic phenotype changes increased the expression of fibrosis-mediated extracellular matrix proteins, such as fibronectin, collagen I, and α-smooth muscle actin. In addition, the level of cellular prion protein (PrPC), which is associated with several biological processes, was decreased by exposure to high glucose conditions. Melatonin recovered the expression levels of PrPC under high glucose conditions via phosphorylation of Akt, resulting in the prevention of high glucose-induced fibrosis. In particular, overexpression of PrPC blocked the high glucose-mediated fibrotic phenotype change. These findings indicate that melatonin could be a powerful agent for treating hyperglycemia-induced renal fibrosis.


Assuntos
Catalase/metabolismo , Fibrose/tratamento farmacológico , Fibrose/metabolismo , Melatonina/uso terapêutico , Fator de Crescimento Transformador beta/metabolismo , Western Blotting , Proliferação de Células/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Fibronectinas/metabolismo , Glucose/farmacologia , Humanos , Túbulos Renais Proximais/citologia , Túbulos Renais Proximais/metabolismo , L-Lactato Desidrogenase/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Priônicas/metabolismo , Ensaio de Radioimunoprecipitação , Transdução de Sinais/efeitos dos fármacos , Células Th1
3.
Clin Lab ; 66(5)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32390377

RESUMO

BACKGROUND: Autoantibodies against the chromosome associated protein DFS70/LEDGF (dense fine speckled 70/ lens epithelial growth factor; anti-DSF70) are increasingly being regarded as biomarkers for the diagnostic exclusion of systemic autoimmune rheumatic diseases (SARD). In routine ANA screening by indirect immunofluores-cence (IIFT) tests the presence of anti-DFS70 may first be presumed because of their characteristic immunofluo-rescence pattern (AC-2 pattern) and then be confirmed by antigen specific assays, a sequential approach, which may underestimate the prevalence of anti-DFS70 because of the inherent shortcomings of the ANA-IIFT. We therefore, for the first time, determined the prevalence of anti-DFS70 in patient sera by means of a sensitive and specific radioimmunoprecipitation assay (RIPA) as compared to a commercial ELISA. METHODS: Blood specimens referred for routine ANA screening (n = 1.100, ANA-Series) or for basic clinical chemistry tests (n = 350, CC-Series) were assayed for the prevalence of anti-DFS70 by RIPA using 35S-methionine labelled full-length DFS70 (FL-DFS70) as well as a C-terminal DFS70 fragment (CT-DFS70) generated by in vitro transcription/translation (ivTT) of the respective cDNAs. ELISA was performed using an anti-DFS70 test-kit (Eu-roimmun) and ANA-IIFT by means of commercial HEp-2 cells (INOVA) and appropriately chessboard titrated conjugates (Dianova). Accessory SARD markers (anti-dsDNA, anti-ENA) were determined in sera positive for anti-DFS70. RESULTS: The detection of anti-DFS70 by RIPA was considerably more sensitive than by ELISA, resulting in an overall detection rate of 9.0% (ANA-Series) and 8.0% (CC-Series) compared to ELISA revealing 4.6% (ANA-Se-ries) and 2.6% (CC-Series) anti-DFS70 positive sera. Of 99 RIPA reactive sera (ANA-Series) 72% were reactive against anti-FL-DFS70, 93% against CT-DFS70, polyspecific antibodies coexisted in 65%, reacting with both antigen specificities, 28% showed monospecific reaction with CT-DFS70 and 7% monospecific with FL-DFS70, indicating also the possible existence of antibodies specific for N-terminal epitopes in DSF70. Similar frequencies were seen in sera of the CC-series. The RIPA measured antibody concentrations (Rratio) obtained with FL-DSF70 antigen and CT-DSF70 antigen showed a correlation. There was also a correlation between the IIFT-ANA titers and Rratio found by RIPA. The consensus of suspected AC-2 pattern in ANA-IIFT and anti-DFS70 measured by RIPA was about 80%. No significant correlation existed between the antibody concentrations measured by RIPA and ELISA. Additional SARD markers were present in 24% of anti-DFS70 positive sera referred for ANA screening. No additional markers were seen in sera of the CC-Series. CONCLUSIONS: RIPA constitutes a highly-sensitive assay for detection of anti-DFS70 in human sera. ANA-IIFT screening performed under consideration of the AC-2 pattern for verification of antibodies to DFS70 under routine conditions may incorrectly estimate a considerable number of not only low but also high titer anti-DSF70 positive sera. The significance of RIPA reactive antibodies, especially of low titer range, in the context of SARD and healthy individuals now has to be scrutinized in further clinical studies.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/imunologia , Anticorpos Antinucleares/sangue , Ensaio de Radioimunoprecipitação/métodos , Fatores de Transcrição/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Autoimunes/diagnóstico , Biomarcadores/sangue , Criança , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Reumáticas/diagnóstico , Adulto Jovem
4.
Proc Natl Acad Sci U S A ; 112(5): 1398-403, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25605922

RESUMO

The cytoplasmic peptide:N-glycanase (PNGase; Ngly1 in mice) is a deglycosylating enzyme involved in the endoplasmic reticulum (ER)-associated degradation (ERAD) process. The precise role of Ngly1 in the ERAD process, however, remains unclear in mammals. The findings reported herein, using mouse embryonic fibroblast (MEF) cells, that the ablation of Ngly1 causes dysregulation of the ERAD process. Interestingly, not only delayed degradation but also the deglycosylation of a misfolded glycoprotein was observed in Ngly1(-/-) MEF cells. The unconventional deglycosylation reaction was found to be catalyzed by the cytosolic endo-ß-N-acetylglucosaminidase (ENGase), generating aggregation-prone N-GlcNAc proteins. The ERAD dysregulation in cells lacking Ngly1 was restored by the additional knockout of ENGase gene. Thus, our study underscores the functional importance of Ngly1 in the ERAD process and provides a potential mechanism underlying the phenotypic consequences of a newly emerging genetic disorder caused by mutation of the human NGLY1 gene.


Assuntos
Acetilglucosamina/metabolismo , Retículo Endoplasmático/metabolismo , Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidase/metabolismo , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/metabolismo , Animais , Células Cultivadas , Camundongos , Mutação , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/genética , Ensaio de Radioimunoprecipitação
5.
Int J Cancer ; 140(12): 2820-2829, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28316082

RESUMO

Dacomitinib-an irreversible pan-ErbB tyrosine kinase inhibitor (TKI)-causes diarrhoea in 75% of patients. Dacomitinib-induced diarrhoea has not previously been investigated and the mechanisms remain poorly understood. The present study aimed to develop an in-vitro and in-vivo model of dacomitinib-induced diarrhoea to investigate underlying mechanisms. T84 cells were treated with 1-4 µM dacomitinib and resistance and viability were measured using transepithelial electrical resistance (TEER) and XTT assays. Rats were treated with 7.5 mg/kg dacomitinib daily via oral gavage for 7 or 21 days (n = 6/group). Weights, and diarrhoea incidence were recorded daily. Rats were administered FITC-dextran 2 hr before cull, and serum levels of FITC-dextran were measured and serum biochemistry analysis was conducted. Detailed histopathological analysis was conducted throughout the gastrointestinal tract. Gastrointestinal expression of ErbB1, ErbB2 and ErbB4 was analysed using RT-PCR. The ileum and the colon were analysed using multiplex for expression of various cytokines. T84 cells treated with dacomitinib showed no alteration in TEER or cell viability. Rats treated with dacomitinib developed severe diarrhoea, and had significantly lower weight gain. Further, dacomitinib treatment led to severe histopathological injury localised to the ileum. This damage coincided with increased levels of MCP1 in the ileum, and preferential expression of ErbB1 in this region compared to all other regions. This study showed dacomitinib induces severe ileal damage accompanied by increased MCP1 expression, and gastrointestinal permeability in rats. The histological changes were most pronounced in the ileum, which was also the region with the highest relative expression of ErbB1.


Assuntos
Diarreia/induzido quimicamente , Trato Gastrointestinal/efeitos dos fármacos , Íleo/efeitos dos fármacos , Quinazolinonas/toxicidade , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quimiocina CCL2/metabolismo , Neoplasias Colorretais/patologia , Diarreia/fisiopatologia , Modelos Animais de Doenças , Receptores ErbB/genética , Receptores ErbB/metabolismo , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/fisiopatologia , Expressão Gênica/efeitos dos fármacos , Humanos , Íleo/metabolismo , Íleo/fisiopatologia , Imuno-Histoquímica , Masculino , Permeabilidade/efeitos dos fármacos , Quinazolinonas/farmacologia , Ensaio de Radioimunoprecipitação , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
Scand J Clin Lab Invest ; 77(6): 465-471, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28678535

RESUMO

The Farr assay is a radioimmunoassay (RIA) for dsDNA antibodies, based on antibody precipitation using ammonium sulphate and quantification using radio-labelled dsDNA. The RIA-Farr assay offers outstanding clinical specificity and sensitivity for systemic lupus erythematosus (SLE) compared to other assays but does also present some disadvantages as it utilizes radioactive-labelled dsDNA and requires high levels of technical expertise for safe handling. Here, a new precipitation assay, 'Fluoro-Farr' assay, is described. This assay maintains a high sensitivity and specificity for SLE but is based on precipitation with polyethylene glycol (PEG) and fluorescence of EvaGreen intercalated in dsDNA as detection principle. As dsDNA antibodies are quantified using fluorescence, the disadvantages of working with radioactivity are eliminated. The Fluoro-Farr assay was developed and validated, and the diagnostic efficiency of the assay was evaluated by testing 57 sera from SLE patients and 60 healthy controls. The Fluoro-Farr assay revealed a diagnostic sensitivity of 68% at a diagnostic specificity of 95% (ROC AUC 0.91). Furthermore, the new Fluoro-Farr assay was compared to the RIA-Farr assay, and showed a correlation of the outcomes from the two assays, but the Fluoro-Farr assay did not outperform the RIA-Farr assay due to its outstanding clinical diagnostic efficiency (ROC AUC 0.99). In conclusion, the Fluoro-Farr assay presents a viable alternative to the traditional RIA-Farr assay; especially in laboratories without facilities to perform assays with radioactivity-based read-out. As the RIA-Farr assay, the Fluoro-Farr assay has the advantage of being a precipitation assay allowing antibody:dsDNA interaction in solution using native dsDNA.


Assuntos
Anticorpos Antinucleares/sangue , Ensaio de Radioimunoprecipitação/métodos , Adulto , Idoso , Animais , Bovinos , Feminino , Fluorescência , Humanos , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Curva ROC , Radioimunoensaio , Reprodutibilidade dos Testes , Adulto Jovem
7.
Int J Mol Sci ; 18(12)2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29206202

RESUMO

Orostachys japonicus A. Berger (), known as Wa-song in Korea, has been reported to exert various biological effects, such as anti-tumor, anti-oxidant, and anti-febrile effects. However, the anti-angiogenic effects of O.japonicus extracts remain to be investigated. In the present study, we demonstrated the anti-angiogenic effects of bioconverted O. japonicus extract (BOE) in Ms-1 mouse endothelial cells and compared them with the bioactivities of O. japonicus extract (OE). BOE, but not OE, were found to exert anti-angiogenic effects, including inhibition of cell migration, cell adhesion, tube formation of Ms-1 cells, and blood vessel formation of matrigel plug assay in vivo. Furthermore, protein levels of phosphorylated Src kinase were lower in BOE-treated cells than in OE-treated cells. Treatment with OE or BOE did not influence cell viability during the experimental period. Bioconverted extract of O.japonicus have anti-angiogenic effects in vitro and vivo, but non-bioconverted extract do not. We suggest that these observed anti-angiogenic effects are caused by the changes in the composition of bioactive compounds in the extracts as a result of biological conversion.


Assuntos
Crassulaceae/química , Células Endoteliais/citologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Animais , Western Blotting , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ensaio de Radioimunoprecipitação
8.
Emerg Infect Dis ; 22(8): 1468-70, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27433974

RESUMO

To assess patterns of Chagas disease, we reviewed results of screening umbilical cord blood from a US public cord blood bank during 2007-2014. Nineteen maternal donors tested positive for Trypanosoma cruzi parasites (0.04%). Because perinatal transmission of Chagas disease is associated with substantial illness, targeted prenatal programs should screen for this disease.


Assuntos
Bancos de Sangue , Doença de Chagas/sangue , Sangue Fetal/parasitologia , Trypanosoma cruzi/isolamento & purificação , Adulto , Doadores de Sangue , Doença de Chagas/epidemiologia , Estudos de Coortes , Feminino , Testes de Hemaglutinação , Humanos , Gravidez , Ensaio de Radioimunoprecipitação , Estudos Retrospectivos
9.
Anal Biochem ; 494: 76-81, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26548958

RESUMO

PolyADP-ribosylation is mediated by poly(ADP-ribose) (PAR) polymerases (PARPs) and may be involved in various cellular events, including chromosomal stability, DNA repair, transcription, cell death, and differentiation. The physiological level of PAR is difficult to determine in intact cells because of the rapid synthesis of PAR by PARPs and the breakdown of PAR by PAR-degrading enzymes, including poly(ADP-ribose) glycohydrolase (PARG) and ADP-ribosylhydrolase 3. Artifactual synthesis and/or degradation of PAR likely occurs during lysis of cells in culture. We developed a sensitive enzyme-linked immunosorbent assay (ELISA) to measure the physiological levels of PAR in cultured cells. We immediately inactivated enzymes that catalyze the synthesis and degradation of PAR. We validated that trichloroacetic acid is suitable for inactivating PARPs, PARG, and other enzymes involved in metabolizing PAR in cultured cells during cell lysis. The PAR level in cells harvested with the standard radioimmunoprecipitation assay buffer was increased by 450-fold compared with trichloroacetic acid for lysis, presumably because of activation of PARPs by DNA damage that occurred during cell lysis. This ELISA can be used to analyze the biological functions of polyADP-ribosylation under various physiological conditions in cultured cells.


Assuntos
Técnicas de Química Analítica/métodos , Ensaio de Imunoadsorção Enzimática , Poli Adenosina Difosfato Ribose/análise , Anticorpos/imunologia , Dano ao DNA , Desoxirribonuclease I/metabolismo , Glicosídeo Hidrolases/metabolismo , Células HEK293 , Células HeLa , Humanos , Poli Adenosina Difosfato Ribose/imunologia , Poli(ADP-Ribose) Polimerases/metabolismo , Ensaio de Radioimunoprecipitação , Endonucleases Específicas para DNA e RNA de Cadeia Simples/metabolismo , Ácido Tricloroacético/química
10.
J Neurochem ; 134(6): 1067-80, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26077708

RESUMO

Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPARs) are the primary mediators for inter-neuronal communication and play a crucial role in higher brain functions including learning and memory. Our previous work demonstrated that AMPARs are subject to ubiquitination by the E3 ligase Nedd4, resulting in EPS15-mediated receptor internalization and Ubiquitin (Ub)-proteasome pathway (UPP)-dependent degradation. Protein ubiquitination is a highly dynamic and reversible process, achieved via the balance between ubiquitination and deubiquitination. However, deubiquitination of mammalian AMPARs and the responsible deubiquitinating enzymes remain elusive. In this study, we identify USP46 as the deubiquitinating enzyme for AMPARs. We find that AMPARs are subject to K63 type ubiquitination, and USP46 is able to deubiquitinate AMPARs in vivo and in vitro. In heterologous cells and neurons, expression of USP46 results in a significant reduction in AMPAR ubiquitination, accompanied by a reduced rate in AMPAR degradation and an increase in surface AMPAR accumulation. By contrast, knockdown of USP46 by RNAi leads to elevated AMPAR ubiquitination and a reduction in surface AMPARs at synapses in neurons. Consistently, miniature excitatory postsynaptic currents recordings show reduced synaptic strength in neurons expressing USP46-selective RNAi. These results demonstrate USP46-mediated regulation of AMPAR ubiquitination and turnover, which may play an important role in synaptic plasticity and brain function. Protein ubiquitination is a highly dynamic and reversible process, achieved via the balance between ubiquitination and deubiquitination. The glutamatergic AMPARs, which mediate most of the excitatory synaptic transmission in the brain, are known to be subjected to Nedd4-mediated ubiquitination; however, the deubiquitination process and the responsible deubiquitinating enzymes (DUBs) for mammalian AMPARs remain elusive. We find that AMPARs are subject to K63-type ubiquitination, and identify USP46 as the DUB for AMPARs. USP46 deubiquitinates AMPARs in vitro and in vivo. Up- or down-regulation of USP46 leads to changes in AMPAR ubiquitination, surface expression, and trafficking, as well as the strength of synaptic transmission. USP46-mediated regulation of AMPAR ubiquitination and turnover may play an important role in synaptic plasticity and brain function.


Assuntos
Encéfalo/fisiologia , Endopeptidases/metabolismo , Plasticidade Neuronal/fisiologia , Receptores de AMPA/metabolismo , Animais , Potenciais Pós-Sinápticos Excitadores/fisiologia , Células HEK293 , Humanos , Imuno-Histoquímica , Técnicas de Patch-Clamp , Transporte Proteico/fisiologia , Ensaio de Radioimunoprecipitação , Ratos , Ratos Sprague-Dawley , Transfecção , Ubiquitinação/fisiologia
11.
Anal Biochem ; 484: 40-50, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25983236

RESUMO

Dendritic cells (DCs) are specialized leukocytes that orchestrate the adaptive immune response. Mass spectrometry (MS)-based proteomic study of these cells presents technical challenges, especially when the DCs are human in origin due to the paucity of available biological material. Here, to maximize MS coverage of the global human DC proteome, different cell disruption methods, lysis conditions, protein precipitation, and protein pellet solubilization and denaturation methods were compared. Mechanical disruption of DC cell pellets under cryogenic conditions, coupled with the use of RIPA (radioimmunoprecipitation assay) buffer, was shown to be the method of choice based on total protein extraction and on the solubilization and identification of nuclear proteins. Precipitation by acetone was found to be more efficient than that by 10% trichloroacetic acid (TCA)/acetone, allowing in excess of 28% more protein identifications. Although being an effective strategy to eliminate the detergent residue, the acetone wash step caused a loss of protein identifications. However, this potential drawback was overcome by adding 1% sodium deoxycholate into the dissolution buffer, which enhanced both solubility of the precipitated proteins and digestion efficiency. This in turn resulted in 6 to 11% more distinct peptides and 14 to 19% more total proteins identified than using 0.5M triethylammonium bicarbonate alone, with the greatest increase (34%) for hydrophobic proteins.


Assuntos
Métodos Analíticos de Preparação de Amostras/métodos , Células Dendríticas/metabolismo , Proteômica/métodos , Espectrometria de Massas em Tandem/métodos , Acetona/química , Soluções Tampão , Precipitação Química , Células Dendríticas/citologia , Humanos , Monócitos/citologia , Octoxinol/química , Desnaturação Proteica , Transporte Proteico , Ensaio de Radioimunoprecipitação , Solubilidade , Ácido Tricloroacético/química
12.
Proc Natl Acad Sci U S A ; 109(36): 14687-92, 2012 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-22912402

RESUMO

Developmental arrest, a critical component of the life cycle in animals as diverse as nematodes (dauer state), insects (diapause), and vertebrates (hibernation), results in dramatic depression of the metabolic rate and a profound extension in longevity. Although many details of the hormonal systems controlling developmental arrest are well-known, we know little about the interactions between metabolic events and the hormones controlling the arrested state. Here, we show that diapause is regulated by an interplay between blood-borne metabolites and regulatory centers within the brain. Gene expression in the fat body, the insect equivalent of the liver, is strongly suppressed during diapause, resulting in low levels of tricarboxylic acid (TCA) intermediates circulating within the blood, and at diapause termination, the fat body becomes activated, releasing an abundance of TCA intermediates that act on the brain to stimulate synthesis of regulatory peptides that prompt production of the insect growth hormone ecdysone. This model is supported by our success in breaking diapause by injecting a mixture of TCA intermediates and upstream metabolites. The results underscore the importance of cross-talk between the brain and fat body as a regulator of diapause and suggest that the TCA cycle may be a checkpoint for regulating different forms of animal dormancy.


Assuntos
Aclimatação/fisiologia , Encéfalo/metabolismo , Comunicação Celular/fisiologia , Corpo Adiposo/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Insetos/crescimento & desenvolvimento , Estágios do Ciclo de Vida/fisiologia , Animais , Sequência de Bases , Primers do DNA/genética , Cromatografia Gasosa-Espectrometria de Massas , Perfilação da Expressão Gênica , Biblioteca Gênica , Modelos Biológicos , Dados de Sequência Molecular , Ensaio de Radioimunoprecipitação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Ácidos Tricarboxílicos/sangue
13.
Ann Neurol ; 73(3): 397-407, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23460448

RESUMO

OBJECTIVE: Sporadic inclusion body myositis (sIBM) is an inflammatory myopathy characterized by both degenerative and autoimmune features. In contrast to other inflammatory myopathies, myositis-specific autoantibodies had not been found in sIBM patients until recently. We used human skeletal muscle extracts as a source of antigens to detect autoantibodies in sIBM and to characterize the corresponding antigen. METHODS: Autoantibodies to skeletal muscle antigens were detected by immunoblotting. The target antigen was immunoaffinity-purified from skeletal muscle extracts and characterized by mass spectrometry. A cDNA encoding this protein was cloned and expressed in vitro, and its recognition by patient sera was analyzed in an immunoprecipitation assay. Epitopes were mapped using microarrays of overlapping peptides. RESULTS: An Mr 44,000 polypeptide (Mup44) was frequently targeted by sIBM autoantibodies. The target protein was purified, and subsequent mass spectrometry analysis revealed that Mup44 is the cytosolic 5'-nucleotidase 1A (cN1A). By immunoprecipitation of recombinant cN1A, high concentrations of anti-Mup44 autoantibodies were detected in 33% of sIBM patient sera, whereas their prevalence in dermatomyositis, polymyositis, and other neuromuscular disorders appeared to be rare (4.2%, 4.5%, and 3.2%, respectively). Low concentrations of anti-Mup44 antibodies were found in myositis as well as other neuromuscular disorders, but not in healthy controls. Three major autoepitope regions of cN1A were mapped by using microarrays containing a set of overlapping peptides covering the complete cN1A amino acid sequence. INTERPRETATION: Anti-Mup44 autoantibodies, which are targeted to cN1A, represent the first serological biomarker for sIBM and may facilitate the diagnosis of this type of myositis.


Assuntos
5'-Nucleotidase/imunologia , Autoanticorpos/sangue , Miosite de Corpos de Inclusão/sangue , Animais , Células Cultivadas , Feminino , Humanos , Imunoprecipitação , Masculino , Espectrometria de Massas , Camundongos , Peso Molecular , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Miosite de Corpos de Inclusão/imunologia , Miosite de Corpos de Inclusão/patologia , Ensaio de Radioimunoprecipitação
14.
Muscle Nerve ; 50(2): 286-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24639380

RESUMO

INTRODUCTION: We adopted a proteomics-based approach to gain insights into phenotypic differences between A/J and B10.SJL murine dysferlinopathy models. METHODS: We optimized immunoblotting of dysferlin by preparing homogenates of the tibialis anterior (TA) muscle under several different conditions. We compared TA muscles of control, A/J, and B10.SJL mice for levels of dysferlin; dysferlin's partners MG53, annexin-A2, and caveolin-3; and the endoplasmic reticulum (ER) stress marker CHOP. We performed immunoelectron microscopy on control rat TA muscle to determine the precise location of dysferlin. RESULTS: RIPA (radioimmunoprecipitation assay) buffer and sonication improves immunoblotting of dysferlin. The ER stress marker CHOP is elevated in A/J muscle. Dysferlin is localized mostly to membranes close to the Z-disk that have been reported to be part of the Golgi, ER, and sarcoplasmic reticulum (SR) networks. CONCLUSIONS: ER stress might underlie phenotypic differences between A/J and B10.SJL mice and play a role in human dysferlinopathies.


Assuntos
Immunoblotting , Distrofia Muscular do Cíngulo dos Membros/diagnóstico , Distrofia Muscular do Cíngulo dos Membros/fisiopatologia , Fenótipo , Animais , Anexina A2/metabolismo , Proteínas de Transporte/metabolismo , Caveolina 3/metabolismo , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/fisiologia , Proteínas de Membrana , Camundongos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Ensaio de Radioimunoprecipitação , Especificidade da Espécie , Fator de Transcrição CHOP/metabolismo
15.
Eur Neurol ; 72(5-6): 271-2, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25277962

RESUMO

BACKGROUND/METHODS: To find out the prevalence of aquaporin-antibody (Aqp-Ab) and characterize Aqp-Ab associated clinical features in NMO, Aqp-1 and Aqp-4-Abs were examined using radioimmunoprecipitation and cell-based assays, respectively. RESULTS: Aqp-4 and Aqp-1-Abs were detected in 20/30 and 8/30 NMO patients, respectively. One patient was Aqp-1-Ab single-positive, 13 patients were Aqp-4-Ab single-positive, 7 patients were Aqp-4/Aqp-1-Ab double-positive and 9 patients were seronegative. All double-positive patients had optic neuritis during the first attack. Only 2/29 MS patients and none of the control idiopathic intracranial hypertension patients were Aqp-1-Ab positive. CONCLUSION: Aqp-1-Ab is usually detected in Aqp-4-Ab positive NMO patients and might be involved in optic neuritis pathogenesis.


Assuntos
Aquaporina 1/imunologia , Autoanticorpos/sangue , Neuromielite Óptica/sangue , Adulto , Aquaporina 4/imunologia , Feminino , Células HEK293 , Humanos , Masculino , Ensaio de Radioimunoprecipitação
16.
Mod Rheumatol ; 24(6): 945-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24670134

RESUMO

BACKGROUND: To confirm the antigen specificities of autoantibodies that precipitate 140-kDa (anti-p140) or 155/140-kDa polypeptides (anti-p155/140) previously identified by radioimmunoprecipitation in Korean patients with dermatomyositis (DM) and to look into the relationship between each MSA and clinical features of DM. METHODS: Seventeen serum samples of classic DM patients who had been found to have either anti-p140 antibodies (n = 9) or anti-p155/140 (n = 8) antibodies in our previous study were examined using enzyme-linked immunosorbent assay (for anti-MDA5 antibodies) and immunoblotting (for anti-MJ/NXP-2 and anti-TIF-1γ antibodies). RESULTS: Seven out of nine anti-p140 antibody positive patients were found to have anti-MDA5 antibodies. Two out of nine had anti-MJ/NXP-2 antibodies with no interstitial lung disease (ILD). All eight anti-p155/140 antibody positive patients were found to have anti-TIF-1γ antibodies. Anti-TIF-1γ and anti-MDA5 antibodies were simultaneously detected in one patient with anti-p155/140 antibody, who suffered HIV infection and non-Hodgkin's lymphoma. The associations between anti-MDA5 antibody and rapidly progressive ILD and between anti-TIF-1γ antibody and cancer-associated DM were confirmed to be significant. CONCLUSIONS: Although radioimmunoprecipitation still looks to be a good screening tool, confirmation with antigen-specific assays seems mandatory. The associations between anti-MDA5 and rapidly progressive ILD and between anti-TIF-1γ and cancer-associated DM were confirmed in Korean patients with DM.


Assuntos
Autoanticorpos/análise , Western Blotting , Dermatomiosite/diagnóstico , Ensaio de Imunoadsorção Enzimática , Ensaio de Radioimunoprecipitação , Adolescente , Adulto , Idoso , Dermatomiosite/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
J Neuromuscul Dis ; 11(3): 613-623, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38578899

RESUMO

Background/Objective: Myasthenia Gravis (MG) is an autoimmune disorder characterized by pathogenic autoantibodies (AAbs) targeting nicotinic acetylcholine receptors (AChR), disrupting neuromuscular communication. RadioImmunoPrecipitation Assay (RIPA) is recommended to detect AChR AAbs, but its complexity and radioactive requirements limit widespread use. We compare non-RIPA anti-AChR immunoassays, including Cell-Based Assay (CBA) and two ELISA kits, against the gold standard RIPA. Methods/Results: 145 samples were included with medical indication for anti-AChR testing. By the RIPA method, 63 were negative (RIPA-Neg < 0.02 nmol/L), 18 were classified as Borderline (≥0.02 -1 nmol/L), and 64 were positive (RIPA-Pos > 1 nmol/L). The competitive ELISA showed poor agreement with RIPA (Kappa = 0.216). The indirect ELISA demonstrated substantial agreement with RIPA (Kappa = 0.652), with ∼76% sensitivity and ∼94% specificity for MG diagnostic. The CBA, where fixed cells expressing clustered AChR were used as substrate, exhibited almost perfect agreement with RIPA (Kappa = 0.984), yielding ∼98% sensitivity and 96% specificity for MG. In addition, a semiquantitative analysis showed a strong correlation between CBA titration, indirect ELISA, and RIPA levels (r = 0.793 and r = 0.789, respectively). Conclusions: The CBA displayed excellent analytical performance for MG diagnostic when compared to RIPA, making it a potential replacement for RIPA in clinical laboratories. Some solid-phase assays (such as the indirect ELISA applied here), as well as CBA titration, offer reliable options to estimate anti-AChR AAb levels after confirming positivity by the CBA.∥.


Assuntos
Autoanticorpos , Ensaio de Imunoadsorção Enzimática , Miastenia Gravis , Ensaio de Radioimunoprecipitação , Humanos , Ensaio de Imunoadsorção Enzimática/métodos , Miastenia Gravis/imunologia , Miastenia Gravis/diagnóstico , Sensibilidade e Especificidade , Receptores Colinérgicos/imunologia , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Idoso , Adulto Jovem
18.
Front Endocrinol (Lausanne) ; 15: 1289923, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38978630

RESUMO

Objective: It is well known that macro-thyroid-stimulating hormone (macro-TSH) could interfere with the detection of TSH. The anti-TSH autoantibody is an essential component of macro-TSH. However, the epidemiological characteristics and the clinical interference of the anti-TSH autoantibody are unclear. Methods: In this study, the radioimmunoprecipitation technique was used to detect the anti-TSH autoantibody. Platforms with different detection mechanisms were applied to measure the TSH in patients with the anti-TSH autoantibody. Polyethylene glycol (PEG) precipitation was used to determine the immunoassay interference. Results: The prevalence of the anti-TSH autoantibody in patients with mild subclinical hypothyroidism (SCH) and autoimmune thyroiditis, but normal thyroid function, was 4.78%. All 10 patients with anti-TSH antibodies had autoimmune diseases, with five of them having significant clinical test interference. Conclusion: The appearance of the anti-TSH antibody is not associated with thyroid autoantibodies. The presence of the anti-TSH autoantibody can interfere with the detection of TSH and can affect clinical diagnosis and treatment.


Assuntos
Autoanticorpos , Hipotireoidismo , Tireotropina , Humanos , Autoanticorpos/sangue , Autoanticorpos/imunologia , Tireotropina/sangue , Tireotropina/imunologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Hipotireoidismo/diagnóstico , Hipotireoidismo/imunologia , Hipotireoidismo/sangue , Tireoidite Autoimune/imunologia , Tireoidite Autoimune/sangue , Tireoidite Autoimune/diagnóstico , Testes de Função Tireóidea , Idoso , Imunoensaio/métodos , Ensaio de Radioimunoprecipitação
19.
Jpn J Clin Oncol ; 43(12): 1261-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24186908

RESUMO

OBJECTIVE: The aim of this study was to examine the level of autophagy in renal clear cell carcinoma, stratify by clinicopathologic grades and stages and compare it with healthy renal tissue in order to hypothesize on the role of autophagy in the proliferation of renal clear cell carcinoma. METHODS: Renal clear cell carcinoma tissue and matched adjacent tissue were collected from 52 patients who had received surgical resection. Autophagosomes were visualized in both renal clear cell carcinomas and adjacent tissue by transmission electron microscopy. Expression of the markers of autophagy, Beclin1 and LC3, was detected by a reverse transcription-polymerase chain reaction. Beclin1 and LC3 protein levels were examined by immunohistochemistry and western blot, and the correlation between autophagy levels and clinicopathologic data was analyzed. RESULTS: Autophagy was down-regulated in renal clear cell carcinomas compared with matched adjacent tissue as measured by the reverse transcriptase-polymerase chain reaction, immunohistochemistry and western blot analyses. Clinicopathologic analyses indicated that advanced or metastatic renal clear cell carcinomas were associated with a lower expression of autophagy compared with localized renal clear cell carcinomas. Similarly, the Fuhrman nuclear grade of renal clear cell carcinomas was negatively correlated with the level of autophagy. Stage, grade and the level of LC3 II were significant factors for prognosis and the low level of LC3 II was associated with poor prognosis of renal clear cell carcinomas. CONCLUSIONS: The results indicate that autophagy is suppressed in renal clear cell carcinomas. The lower levels of autophagy are correlated with the higher stages and grades of renal clear cell carcinomas. Furthermore, a low level of LC3 II indicates poor prognosis of renal clear cell carcinoma. This is suggestive of association between the low level of autophagy and progression of renal clear cell carcinoma.


Assuntos
Proteínas Reguladoras de Apoptose/análise , Autofagia , Biomarcadores Tumorais/análise , Carcinoma de Células Renais/química , Neoplasias Renais/química , Proteínas de Membrana/análise , Proteínas Associadas aos Microtúbulos/análise , Proteínas Reguladoras de Apoptose/genética , Proteína Beclina-1 , Biomarcadores Tumorais/genética , Western Blotting , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Rim/química , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Proteínas de Membrana/genética , Proteínas Associadas aos Microtúbulos/genética , Gradação de Tumores , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , RNA Mensageiro/metabolismo , Ensaio de Radioimunoprecipitação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
J Dairy Sci ; 96(2): 806-14, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23200479

RESUMO

Rotavirus is the most important etiologic agent of severe gastroenteritis. Previously, we reported that skimmed and concentrated bovine late colostrum (SCBLC) obtained from normal unimmunized cows at 6 to 7d after parturition effectively prevented against human rotavirus (HRV)-induced severe gastroenteritis in vivo, when administered as a single dose 60 min before viral inoculation. In the present study, we examined the efficacy of multiple administrations of SCBLC at smaller dosages after viral inoculation in vivo. We demonstrate that multiple administrations within 24h after virus inoculation resulted in earlier recovery from diarrheal symptoms, in an administration frequency-dependent manner. Furthermore, we investigated whether isolated IgG anti-HRV activity in SCBLC was equivalent to that of IgG isolated from bovine mature milk as measured by in vitro activity assays. We found that IgG-containing fractions from SCBLC and mature milk exhibited approximately the same level of anti-HRV activity. We concluded that the SCBLC contains a high level of IgG against HRV-induced severe gastroenteritis, which will be possible to use in protective effects in immunocompromised hosts, such as children and the elderly. Multiple doses of SCBLC during the early stages of infection or lower dosage of SCBLC given as a single dose both resulted in relief of diarrheal symptoms.


Assuntos
Colostro/imunologia , Diarreia/prevenção & controle , Infecções por Rotavirus/terapia , Animais , Animais Lactentes/imunologia , Bovinos , Diarreia/imunologia , Diarreia/virologia , Modelos Animais de Doenças , Gastroenterite/imunologia , Gastroenterite/prevenção & controle , Gastroenterite/virologia , Humanos , Imunoglobulina G/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ensaio de Radioimunoprecipitação , Rotavirus/imunologia , Infecções por Rotavirus/imunologia
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