RESUMO
α,α-trehalose is a well-known sugar that plays a key role in establishing tolerance to environmental stresses in many organisms, except unicellular eukaryotes. However, almost nothing is known about α,ß-trehalose, including their synthesis, function, and even presence in living organisms. In this study, we identified α,ß-trehalose in the resting cyst, a dormancy cell form characterized by extreme tolerance to environmental stresses, of the ciliated protist Colpoda cucullus, using high-performance liquid chromatography (HPLC), and a proton nuclear magnetic resonance (1H NMR). Gene expression analysis revealed that the expression of trehalose-6-phosphate synthase (TPS), glycosyltransferase (GT), alpha-amylase (AMY), and trehalose transporter 1 (TRET1), were up-regulated in encystment, while the expression of α-glucosidase 2 (AG2) and trehalase (TREH) was up-regulated in excystment. These results suggest that α,ß-trehalose is synthesized during encystment process, while and contributes to extreme tolerances to environmental stressors, stored carbohydrates, and energy reserve during resting cyst and/or during excystment.
Assuntos
Cilióforos , Trealose , Cilióforos/metabolismo , Cilióforos/genética , Trealose/metabolismo , Trealose/análogos & derivados , Estresse Fisiológico , Glucosiltransferases/metabolismo , Glucosiltransferases/genéticaRESUMO
Fungi belonging to the Ascomycete genus Cordyceps are endoparasitoids and parasites, mainly of insects and other arthropods. Cordyceps militaris has been used as a therapeutic drug for cancer patients. However, the infection, parasitism, and fruiting body formation mechanisms of this fungus are still unknown. Based on our hypothesis that lectin(s) is involved in the interaction between the C. militaris fungi and insects, we partially purified and characterized a new lectin from C. militaris, designated CmLec4. In addition, we searched for substance(s) in the infected silkworm extracts that could bind to CmLec4, and succeeded in purifying the sex-specific storage protein 2 as a specific binding target. To examine function of the binding protein during the process of parasitism, we investigated the effect of recombinant CmLec4 on silkworms by inoculating the protein into silkworm pupae, and found that it significantly delayed emergence compared to the control. Furthermore, cmlec4 gene knockout strains constructed in this study produced markedly lower amounts of fruiting body than the wild-type strain. All the results revealed that the lectin CmLec4 produced by C. militaris would be involved in the infection into silkworm and fruiting body formation from the host.
Assuntos
Cordyceps , Animais , Cordyceps/química , Carpóforos/química , Humanos , Insetos , Lectinas/metabolismo , PupaRESUMO
INTRODUCTION: The objective of this study was to clarify the clinical differences between nursing and healthcare-associated pneumonia (NHCAP) and community-acquired pneumonia (CAP) due to COVID-19. We also investigated the clinical characteristics to determine whether there is a difference between the variant and non-variant strain in patients with NHCAP due to COVID-19. In addition, we analyzed the clinical outcomes in NHCAP patients with mental disorders who were hospitalized in a medical institution for treatment of mental illness. METHODS: This study was conducted at five institutions and assessed a total of 836 patients with COVID-19 pneumonia (154 cases were classified as NHCAP and 335 had lineage B.1.1.7.). RESULTS: No differences in patient background, clinical findings, disease severity, or outcomes were observed in patients with NHCAP between the non-B.1.1.7 group and B.1.1.7 group. The median age, frequency of comorbid illness, rates of intensive care unit stay, and mortality rate were significantly higher in patients with NHCAP than in those with CAP. Among the patients with NHCAP, the mortality rate was highest at 37.5% in patients with recent cancer treatment, followed by elderly or disabled patients receiving nursing care (24.3%), residents of care facilities (23.0%), patients receiving dialysis (13.6%), and patients in mental hospitals (9.4%). CONCLUSIONS: Our results demonstrated that there were many differences in the clinical characteristics between NHCAP patients and CAP patients due to COVID-19. It is necessary to consider the prevention and treatment content depending on the presence or absence of applicable criteria for NHCAP.
Assuntos
COVID-19 , Infecções Comunitárias Adquiridas , Infecção Hospitalar , Pneumonia Associada a Assistência à Saúde , Pneumonia , Idoso , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecção Hospitalar/tratamento farmacológico , Humanos , SARS-CoV-2RESUMO
BACKGROUND: Salvage surgery is an effective therapeutic option for patients experiencing relapses after chemoradiotherapy for advanced-stage lung cancer or after high-dose radiotherapy for early-stage lung cancer. We report a case involving an emergent salvage surgery for a patient with massive hemoptysis who developed lung cancer recurrence after undergoing proton beam therapy 7 years prior to presentation. CASE PRESENTATION: A 70-year-old male patient was emergently admitted due to massive hemoptysis. He had undergone proton beam therapy for a stage I adenocarcinoma of the left upper lobe 7 years ago, and was receiving chemotherapy for local recurrence. We performed an emergent salvage pulmonary resection to achieve hemostasis. During the operation, we confirmed the presence of a left broncho-pulmonary arterial fistula, which was considered as the origin of the massive hemoptysis. We repaired the fistula between the pulmonary artery and left upper bronchus without incident; an orifice of the fistula at the left pulmonary artery was sutured using a non-absorbable monofilament, and the central portion of the orifice of the fistula at the left upper bronchus was closed with a mechanical stapling device. The postoperative diagnosis was of an adenocarcinoma-ypT3(pm1) N0M1a (dissemination)-IVA, ef1b. The patient has survived for over a year with the cancer in almost complete remission following the administration of an epidermal growth factor receptor tyrosine kinase inhibitor. CONCLUSIONS: Emergent salvage surgery demands high skill levels with optimal timing and correct patient selection. Our case suggested that the procedure played an important role in controlling serious bleeding and/or infectious conditions. Consequently, he could receive chemotherapy again and survive for over a year.
RESUMO
Two kinds of tetravalent double-headed sialo-glycosides with short/long spacers between the Neu5Acα2,6Galß1,4GlcNAc unit and ethylene glycol tetraacetic acid (EGTA) scaffold were found to be capable of binding to virus-like particles of Merkel cell polyomavirus (MCPyV-LP). The binding process and time course of interaction between the tetravalent ligand and MCPyV-LP were assessed by dynamic light scattering (DLS). On the addition of increasing concentrations of ligand to MCPyV-LP, larger cross-linked aggregates formed until a maximum size was reached. The binding was stronger for the tetravalent ligand with a short spacer than for that with a long spacer. The binding of the former ligand to the virus was observed to proceed in two stages during agglutination. The first step was the spontaneous formation of small aggregates comprising the cross-linked ligand-virus complex. In the second step, the aggregates grew successively larger by cooperative binding among the initially produced small aggregates. In transmission electron microscopy, the resulting complex was observed to form aggregates in which the ligands were closely packed with the virus particles. The cross-linked interaction was further confirmed by a simple membrane filtration assay in which the virus-like particles were retained on the membrane when complexed with a ligand. The assay also showed the effective capture of particles of pathogenic, infectious human polyomavirus JCPyV when complexed with a ligand, suggesting its possible application as a method for trapping viruses by filtration under conditions of virus aggregation. Collectively, these results show that the tetravalent glycocluster serves as a ligand not only for agglutinating MCPyV-LP but also for trapping the pathogenic virus.
RESUMO
Immune checkpoint inhibitors have markedly changed lung cancer treatment and improved overall survival. However, immune checkpoint inhibitors may be associated with various adverse events, including encephalitis, although this complication is rare. We herein describe the clinical characteristics of a case of immune checkpoint inhibitor-induced encephalitis and its management. A 51-year-old man with squamous non-small cell lung cancer was receiving pembrolizumab treatment when he suddenly displayed an altered level of consciousness. Cerebrospinal fluid examination revealed elevated lymphocyte count and autoimmune encephalitis was suspected. The patient was promptly started on steroids and his consciousness immediately improved. Pembrolizumab treatment was discontinued; however, stable disease was maintained. In conclusion, encephalitis is a rare but possibly fatal adverse event of immune checkpoint inhibitors, and prompt diagnosis and treatment are mandatory.
RESUMO
BACKGROUND: Immune checkpoint inhibitors have dramatically changed lung cancer treatment, demonstrating an overall survival benefit. There are limited data about re-challenge in patients with non-small cell lung cancer. We attempted to address this question for re-challenge of immune checkpoint inhibitor in patients with advanced non-small cell lung cancer. METHODS: We retrospectively analyzed 11 patients with advanced non-small cell lung cancer treated with nivolumab and re-challenged with nivolumab/pemblorizumab at Kansai Medical University Hospital from December 2015 to December 2017. RESULTS: Three patients achieved PR and two patients were in SD. These patients were apt to be good responders to the initial treatment, to develop immune-related adverse events and to be immediately started on re-challenge with immune checkpoint inhibitor. The median PFS was 2.7 (range, 0.5-16.1) months. Five patients (45%) had mild to moderate immune-related adverse events. CONCLUSION: Our study shows the effectiveness of re-challenge of immune checkpoint inhibitors in a subset of non-small cell lung cancer patients. Re-challenge might become one of treatment option for advanced non-small cell lung cancer.
RESUMO
BACKGROUND: There is an unmet need to identify markers that predict the response to nivolumab in patients with non-small-cell lung cancer (NSCLC). The neutrophil-to-lymphocyte ratio (NLR) was recently recognized as an indicator of a poor prognosis in patients with various cancers. In the present study, we quantified the predictive impact of NLR in patients with NSCLC treated with nivolumab. METHODS: We retrospectively analyzed 101 patients with advanced NSCLC treated with nivolumab at Kansai Medical University Hospital from December 2015 to December 2016. Patients were administered nivolumab at a dose of 3 mg/kg every 2 weeks. The predictive value of NLR for disease progression before treatment and 2 and 4 weeks after nivolumab treatment was assessed. RESULTS: The median progression-free survival (PFS) of patients with an NLR of < 3 before treatment was 3.4 months, whereas that of patients with an NLR of ≥ 3 was 2.9 months (p = 0.484). The median PFS of patients with an NLR of < 3 at 2 weeks after treatment was 5.3 months, whereas that of patients with an NLR of ≥ 3 was 2.1 months (p = 0.00528). The median PFS of patients with an NLR of < 3 at 4 weeks after treatment was 5.3 months, whereas that of patients with an NLR of ≥ 3 was 2.0 months (p = 0.00515). CONCLUSION: The NLR at 2 and 4 weeks after treatment might be a useful marker for the prediction of the treatment response or disease progression in patients with advanced NSCLC receiving nivolumab.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Biomarcadores/análise , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Linfócitos/patologia , Neutrófilos/patologia , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Progressão da Doença , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Nivolumabe , Prognóstico , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
A retrospective study was conducted to investigate the efficacy and toxicity of single-agent nab-paclitaxel in 67 patients with platinum-resistant non-small cell lung cancer in Kansai Medical University Hospital from August 2013 to December 2015. Overall, 25% of patients experienced disease progression, 48% exhibited a partial response, 27% had stable disease and 0% had a complete response. The median progression-free survival (PFS) time was 4.8 months and the median overall survival time was 18.2 months. There was no statistically significant difference in PFS between patients with non-squamous carcinoma and squamous carcinoma, or between second-line use and post-second-line use. The most common severe adverse event was neutropenia, followed by interstitial lung disease, infection and fatigue. The results revealed that single agent nab-paclitaxel was associated with an acceptable level of toxicity and a favorable response. This regimen has been developed recently, thus it has not been sufficiently evaluated its toxicity and efficacy. Additional studies to evaluate these parameters in non-small cell lung cancer are warranted.
RESUMO
Interstitial lung disease (ILD) is a serious and potentially fatal adverse event in lung cancer therapy. Nanoparticle albumin-bound paclitaxel (nab-PTX) is a novel, solvent-free formulation of paclitaxel (PTX). Although the incidence of nab-PTX-induced ILD is not clear, it is generally considered that this formulation presents a similar risk of developing ILD as PTX. Here, we report 3 patients who developed severe ILD following treatment with nab-PTX. We draw attention to the risk of developing drug-induced ILD following nab-PTX treatment, and highlight that this novel formulation might therefore not be as safe as PTX with respect to the development of ILD.
RESUMO
BACKGROUND: Epidermal growth factor receptor tyrosine kinase inhibitors significantly prolong the progression-free survival of patients with non-squamous non-small cell lung cancer (NSCLC). However, most patients develop tumor regrowth and their prognosis remains poor. A new treatment strategy for NSCLC harboring EGFR mutation is therefore necessary. METHODS: In phase I, eligible patients were administered oral erlotinib daily and intravenous pemetrexed, carboplatin, and bevacizumab every 3 weeks for four cycles with maintenance of pemetrexed and bevacizumab until progressive disease was observed. The dose of erlotinib was 100 mg for dose level 1 and 150 mg for dose level 2. The doses of pemetrexed, carboplatin, and bevacizumab were fixed at 500 mg/m2, area under the concentration-time curve of 6 mg/mL · min, and 15 mg/kg, respectively. The dose-limiting toxicities were grade 3/4 neutropenia with fever or infection, grade 4 leukopenia lasting for ≥7 days, grade 4 thrombocytopenia, grade 3/4 uncontrollable nonhematological toxicity, and delayed administration of the subsequent cycle by >2 weeks because of adverse events. RESULTS: Six patients were enrolled in phase I (dose level 1, n = 3; dose level 2, n = 3). During the induction phase, grade 3 neutropenia without fever was observed in one patient at dose level 1 and two patients at dose level 2. Grade 3 anemia was reported in one patient at dose level 1 and grade 3 thrombocytopenia was reported in two patients at dose level 1 and dose level 2, respectively. CONCLUSION: Four-drug combination therapy is a feasible and promising.
RESUMO
Bevacizumab(Avastin(®) ), a humanized therapeutic monoclonal antibody that targets vascular endothelial growth factor, is widely used in cancer treatment. Patients who are treated with bevacizumab have an increased risk of developing systemic hypertension. However, the relationship between bevacizumab-induced hypertension and clinical outcome remains unclear. We aimed to evaluate the effect of bevacizumab-induced hypertension in terms of prognosis in patients with colorectal cancer and non-small cell lung cancer. The study included 632 patients, 317 patients with non-small cell lung cancer and 315 patients with colorectal cancer. All patients were treated with bevacizumab in combination with standard chemotherapy protocols, between April 2007 and December 2014. Blood pressure was measured before each treatment cycle. In the patient group with colorectal cancer, treated with bevacizumab, Grade 2-3 hypertension was present in 27.6%. In hypertensive patients with colorectal cancer, median overall survival was 42.6 months, compared with 20.6 months for normotensive patients in this group (P = 0.00071). In the patient group with non-small cell lung cancer, treated with bevacizumab, Grade 2-3 hypertension was present in 20.5%. In hypertensive patients with non-small cell lung cancer, median overall survival was 43.0 months, compared with 26.3 months for normotensive patients in this group (P = 0.00451). Patients who developed hypertension during treatment with bevacizumab for colorectal cancer and non-small cell lung cancer had significantly prolonged overall survival when compared with normotensive patients. Bevacizumab-induced hypertension may represent a biomarker for clinical benefit in cancer patients treated with bevacizumab.
Assuntos
Inibidores da Angiogênese/efeitos adversos , Antineoplásicos/efeitos adversos , Bevacizumab/efeitos adversos , Neoplasias Colorretais/complicações , Hipertensão/etiologia , Neoplasias Pulmonares/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/administração & dosagem , Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/administração & dosagem , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/mortalidade , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Avaliação de Resultados da Assistência ao Paciente , Prognóstico , Estudos RetrospectivosRESUMO
At our hospital, we use aprepitant for nausea and vomiting when administering highly emetic anticancer agents, according to "Guidelines for the Appropriate Use of Antiemetic Agents" given by the Japan Society of Clinical Oncology. We initiated the intravenous administration of fosaprepitant for better compliance compared with aprepitant; however, we observed phlebitis after the infusion of fosaprepitant. Therefore, we investigated measures to reduce phlebitis associated with the infusion of fosaprepitant. For the first premedication, fosaprepitant (150 mg) was dissolved in 100 mL of saline and administered for 30 minutes; 1 of 2 patients showed grade 4 phlebitis. For the modified premedication, fosaprepitant, dexamethasone, and 5- HT(3) antagonist were dissolved in 100 mL of saline and administered for 30 minutes. The modified premedication was administered to a total of 27 patients; 5 patients developed mild phlebitis (grade 1), but infusion could be continued by treating their phlebitis with a hot pack. We used a combination of dexamethasone and 5-HT(3) antagonist with fosaprepitant as a modified premedication in order to avoid drug-induced vascular damage, which resulted in the pH decreasing to 6.20-7.55 (close to neutral) and a shorter infusion time.
Assuntos
Antineoplásicos/efeitos adversos , Morfolinas/uso terapêutico , Neoplasias/tratamento farmacológico , Flebite/prevenção & controle , Adulto , Idoso , Antineoplásicos/uso terapêutico , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Morfolinas/administração & dosagem , Flebite/induzido quimicamente , Fatores de RiscoRESUMO
The present study evaluated the efficacy and safety of pemetrexed, carboplatin and bevacizumab, followed by maintenance pemetrexed and bevacizumab, in chemotherapy-naïve patients with stage IIIB/IV non-squamous non-small cell lung cancer (NSCLC). The patients were administered pemetrexed (500 mg/m2), carboplatin (area under the concentration-time curve, 6.0 mg/ml × min) and bevacizumab (15 mg/kg) intravenously every three weeks for up to six cycles. Patients who did not experience tumor progression remained on maintenance pemetrexed and bevacizumab until disease progression or unacceptable toxicity occurred. The primary endpoint was the overall response rate. Of the 26 patients enrolled between March 2010 and April 2011, three were excluded due to brain metastases, therefore the intention-to-treat (ITT) population consisted of 23 patients. The median age was 64 years (range, 40-74 years) and 15 patients were male. In total, six patients had a performance status of 0, and 20 had stage IV tumors. The response rate was 69.6% [95% confidence interval (CI), 47.1-86.8], the disease control rate was 100% and the time to response was 1.2 months (95% CI, 0.72-1.93). The median progression-free survival time was 8.6 months (95% CI, 5.9-10.9) and the median overall survival time was 18.6 months (95% CI, 12.9-24.8). There were no grade 3 or worse hemorrhagic events and the feasibility was modest. Overall, pemetrexed and carboplatin plus bevacizumab, followed by maintenance pemetrexed and bevacizumab, was effective and tolerable in the patients with non-squamous NSCLC, and the time to response was relatively short.
RESUMO
Docetaxel is a well-known causative agent of nail alterations. The aim of this study was to reveal the impact of nail alterations associated with low-dose metronomic (LDM) docetaxel chemotherapy on the survival of non-small cell lung cancer (NSCLC) patients. Clinical information, survival data and nail alterations in patients treated with LDM docetaxel chemotherapy (docetaxel 15 mg/m2 per week) were retrospectively reviewed. Forty-nine patients were included in this study. Various nail alterations were observed in 17 of the 49 patients (34.7%). Onycholysis and subungual hyperkeratosis were observed in 22.4% and 10.2% of patients, respectively. The number of docetaxel administration cycles was correlated with the incidence and severity of nail alterations. Univariate and multivariate analysis clearly demonstrated that the occurrence of nail alterations was an independent favorable prognostic factor for overall survival. Nail alterations associated with treatment may act as a surrogate marker for the efficacy of low-dose metronomic docetaxel chemotherapy.
RESUMO
INTRODUCTION: To date, an epidermal growth factor receptor-activating mutation is recognized as a genetic hallmark that predicts a good response to treatment with epidermal growth factor receptor tyrosine kinase inhibitor. However, there has been less long-term observation of the mutational status within the same patient. To the best of our knowledge, this is the first case report which illustrates the instability of the genetic status of pulmonary adenocarcinoma cells. CASE PRESENTATION: A 64-year-old Japanese woman with advanced lung adenocarcinoma had been undergoing various anticancer treatments, including epidermal growth factor receptor tyrosine kinase inhibitor, for seven years. She had been receiving locoregional treatment in addition to systemic treatment. She maintained a good performance status until seven years after the initial diagnosis, although she had local and distant recurrences. We analyzed the genetic status of the epidermal growth factor receptor gene in a series of specimens obtained from various tumor-containing lesions throughout the therapeutic period. The results of the genetic analyses clearly showed that the spatial and temporal genetic heterogeneity of the epidermal growth factor receptor gene status originated from an identical tumor ancestor. CONCLUSIONS: An alternative paradigm to determine a therapeutic strategy for a patient with lung cancer should be considered given the genetic heterogeneity and instability of tumor cells.
RESUMO
Aflatoxin B(1) (AFB(1) ) is a potent mycotoxin with mutagenic, carcinogenic, teratogenic, hepatotoxic, and immunosuppressive properties. In order to develop a bioremediation system for AFB(1) -contaminated foods by white-rot fungi or ligninolytic enzymes, AFB(1) was treated with manganese peroxidase (MnP) from the white-rot fungus Phanerochaete sordida YK-624. AFB(1) was eliminated by MnP. The maximum elimination (86.0%) of AFB(1) was observed after 48 h in a reaction mixture containing 5 nkat of MnP. The addition of Tween 80 enhanced AFB(1) elimination. The elimination of AFB(1) by MnP considerably reduced its mutagenic activity in an umu test, and the treatment of AFB(1) by 20 nkat MnP reduced the mutagenic activity by 69.2%. (1) H-NMR and HR-ESI-MS analysis suggested that AFB(1) is first oxidized to AFB(1) -8,9-epoxide by MnP and then hydrolyzed to AFB(1) -8,9-dihydrodiol. This is the first report that MnP can effectively remove the mutagenic activity of AFB(1) by converting it into AFB(1) -8,9-dihydrodiol.
Assuntos
Aflatoxina B1/metabolismo , Peroxidases/metabolismo , Phanerochaete/enzimologia , Biotransformação , Ativadores de Enzimas/metabolismo , Espectroscopia de Ressonância Magnética , Mutagênicos/metabolismo , Polissorbatos/metabolismoRESUMO
INTRODUCTION: Plasmacytoid dendritic cells (pDCs) play not only a central role in the antiviral immune response in innate host defense, but also a pathogenic role in the development of the autoimmune process by their ability to produce robust amounts of type I interferons (IFNs), through sensing nucleic acids by toll-like receptor (TLR) 7 and 9. Thus, control of dysregulated pDC activation and type I IFN production provide an alternative treatment strategy for autoimmune diseases in which type I IFNs are elevated, such as systemic lupus erythematosus (SLE). Here we focused on IkappaB kinase inhibitor BAY 11-7082 (BAY11) and investigated its immunomodulatory effects in targeting the IFN response on pDCs. METHODS: We isolated human blood pDCs by flow cytometry and examined the function of BAY11 on pDCs in response to TLR ligands, with regards to pDC activation, such as IFN-alpha production and nuclear translocation of interferon regulatory factor 7 (IRF7) in vitro. Additionally, we cultured healthy peripheral blood mononuclear cells (PBMCs) with serum from SLE patients in the presence or absence of BAY11, and then examined the inhibitory function of BAY11 on SLE serum-induced IFN-alpha production. We also examined its inhibitory effect in vivo using mice pretreated with BAY11 intraperitonealy, followed by intravenous injection of TLR7 ligand poly U. RESULTS: Here we identified that BAY11 has the ability to inhibit nuclear translocation of IRF7 and IFN-alpha production in human pDCs. BAY11, although showing the ability to also interfere with tumor necrosis factor (TNF)-alpha production, more strongly inhibited IFN-alpha production than TNF-alpha production by pDCs, in response to TLR ligands. We also found that BAY11 inhibited both in vitro IFN-alpha production by human PBMCs induced by the SLE serum and the in vivo serum IFN-alpha level induced by injecting mice with poly U. CONCLUSIONS: These findings suggest that BAY11 has the therapeutic potential to attenuate the IFN environment by regulating pDC function and provide a novel foundation for the development of an effective immunotherapeutic strategy against autoimmune disorders such as SLE.
Assuntos
Núcleo Celular/metabolismo , Células Dendríticas/metabolismo , Quinase I-kappa B/antagonistas & inibidores , Quinase I-kappa B/metabolismo , Fator Regulador 7 de Interferon/metabolismo , Interferon Tipo I/metabolismo , Nitrilas/farmacologia , Sulfonas/farmacologia , Adulto , Animais , Transporte Biológico/efeitos dos fármacos , Células Cultivadas , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Interferon-alfa/metabolismo , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lúpus Eritematoso Sistêmico/metabolismo , Lúpus Eritematoso Sistêmico/patologia , Camundongos , Camundongos Endogâmicos C57BL , Modelos AnimaisRESUMO
BACKGROUND: Sialic acid is a deoxy uronic acid with a skeleton of nine carbons which is mostly found on cell surface in animals. This sialic acid on cell surface performs various biological functions by acting as a receptor for microorganisms, viruses, toxins, and hormones; by masking receptors; and by regulating the immune system. In order to synthesize an artificial sialoglycoprotein, we developed a large-scale production of rat alpha2,6-sialyltransferase (ST6Gal1). The ST6Gal1 was expressed in fifth instar silkworm larval hemolymph using recombinant both cysteine protease- and chitinase-deficient Bombyx mori nucleopolyhedrovirus (BmNPV-CP--Chi-) bacmid. The expressed ST6Gal1 was purified, characterized and used for sialylation of asialoglycopolypeptide. We tested the inhibitory effect of the synthesized alpha2,6-sialoglycopolypeptide on hemagglutination by Sambucus nigra (SNA) lectin. RESULTS: FLAG-tagged recombinant ST6Gal1 was expressed efficiently and purified by precipitation with ammonium sulphate followed by affinity chromatography on an anti-FLAG M2 column, generating 2.2 mg purified fusion protein from only 11 silkworm larvae, with a recovery yield of 64%. The purified ST6Gal1 was characterized and its N-glycan patterns were found to be approximately paucimannosidic type by HPLC mapping method. Fluorescently-labelled N-acetyllactosamine (LacNAc) glycoside containing dansyl group was synthesized chemo-enzymatically as high-sensitivity acceptor substrate for ST6Gal1. The acceptor substrate specificity of the enzyme was similar to that of rat liver ST6Gal1. The fluorescent glycoside is useful as a substrate for a highly sensitive picomole assay of ST6Gal1. Asialoglycopolypeptide was regioselectively and quantitatively sialylated by catalytic reaction at the terminal Gal residue to obtain alpha2,6-sialoglycopolypeptide using ST6Gal1. The alpha2,6-sialoglycopolypeptide selectively inhibited hemagglutination induced by Sambucus nigra (SNA) lectin, showing about 780-fold higher affinity than the control fetuin. Asialoglycopolypeptide and gamma-polyglutamic acid did not affect SNA lectin-mediated hemagglutination. CONCLUSION: The recombinant ST6Gal1 from a silkworm expression system is useful for the sialylation of asialoglycopeptide. The sialylated glycoprotein is a valuable tool for investigating the molecular mechanisms of biological and physiological events, such as cell-cell recognition and viral entry during infection.
Assuntos
Bombyx/metabolismo , Nucleopoliedrovírus/genética , Proteínas Recombinantes/biossíntese , Sialoglicoproteínas/biossíntese , Sialiltransferases/biossíntese , Animais , Antivirais/metabolismo , Bombyx/virologia , Clonagem Molecular , Vetores Genéticos , Testes de Inibição da Hemaglutinação , Larva/metabolismo , Larva/virologia , Orthomyxoviridae/efeitos dos fármacos , Lectinas de Plantas/metabolismo , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Inativadoras de Ribossomos/metabolismo , Sialoglicoproteínas/genética , Sialoglicoproteínas/isolamento & purificação , Sialiltransferases/genética , Sialiltransferases/isolamento & purificação , beta-D-Galactosídeo alfa 2-6-SialiltransferaseRESUMO
Atopic dermatitis is a major allergic disease that develops through dysregulation of Th2-mediated inflammation. Although dendritic cells (DCs) have been thought to play a critical role in the upstream phase of the allergic cascade, conventional drugs such as steroids and chemical mediator antagonists target the effector cells or factors in allergic inflammation. Recently, it has been demonstrated that interaction between thymic stromal lymphopoietin (TSLP) and human DCs plays an essential role in evoking inflammatory Th2 responses in allergy through OX40 ligand expression on DCs. In this study, we provide evidence that R848, an imidazoquinoline compound, which is a TLR ligand and a strong Th1 response-inducing reagent, is a potent adjuvant for the alteration of the Th2-inducing potency of human DCs activated by TSLP (TSLP-DCs). R848 inhibited the inflammatory Th2-inducing capacity of TSLP-DCs and redirected them to possessing an IL-10 and IFN-gamma-producing regulatory Th1-inducing capacity. This functional alteration depended on both repression of OX40 ligand expression and induction of IL-12 production from DCs by the addition of R848. Additionally, R848 had the ability to inhibit the TSLP-mediated expansion and maintenance of the Th2 memory response. These findings suggest that imidazoquinoline may be a useful in the treatment of allergic diseases that are triggered by TSLP.