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1.
Rheumatology (Oxford) ; 63(2): 551-562, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37341646

RESUMO

OBJECTIVES: Platelets and low-density neutrophils (LDNs) are major players in the immunopathogenesis of SLE. Despite evidence showing the importance of platelet-neutrophil complexes (PNCs) in inflammation, little is known about the relationship between LDNs and platelets in SLE. We sought to characterize the role of LDNs and Toll-like receptor 7 (TLR7) in clinical disease. METHODS: Flow cytometry was used to immunophenotype LDNs from SLE patients and controls. The association of LDNs with organ damage was investigated in a cohort of 290 SLE patients. TLR7 mRNA expression was assessed in LDNs and high-density neutrophils (HDNs) using publicly available mRNA sequencing datasets and our own cohort using RT-PCR. The role of TLR7 in platelet binding was evaluated in platelet-HDN mixing studies using TLR7-deficient mice and Klinefelter syndrome patients. RESULTS: SLE patients with active disease have more LDNs, which are heterogeneous and more immature in patients with evidence of kidney dysfunction. LDNs are platelet bound, in contrast to HDNs. LDNs settle in the peripheral blood mononuclear cell (PBMC) layer due to the increased buoyancy and neutrophil degranulation from platelet binding. Mixing studies demonstrated that this PNC formation was dependent on platelet-TLR7 and that the association results in increased NETosis. The neutrophil:platelet ratio is a useful clinical correlate for LDNs, and a higher NPR is associated with past and current flares of LN. CONCLUSIONS: LDNs sediment in the upper PBMC fraction due to PNC formation, which is dependent on the expression of TLR7 in platelets. Collectively, our results reveal a novel TLR7-dependent crosstalk between platelets and neutrophils that may be an important therapeutic opportunity for LN.


Assuntos
Nefrite Lúpica , Neutrófilos , Animais , Humanos , Camundongos , Leucócitos Mononucleares , Nefrite Lúpica/patologia , Neutrófilos/metabolismo , RNA Mensageiro/metabolismo , Receptor 7 Toll-Like/genética
2.
J Control Release ; 360: 344-364, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37406819

RESUMO

Atherosclerosis is a chronic inflammatory vascular disease that is characterized by the accumulation of lipids and immune cells in plaques built up inside artery walls. Docosahexaenoic acid (DHA, 22:6n-3), an omega-3 polyunsaturated fatty acid (PUFA), which exerts anti-inflammatory and antioxidant properties, has long been purported to be of therapeutic benefit to atherosclerosis patients. However, large clinical trials have yielded inconsistent data, likely due to variations in the formulation, dosage, and bioavailability of DHA following oral intake. To fully exploit its potential therapeutic effects, we have developed an injectable liposomal DHA formulation intended for intravenous administration as a plaque-targeted nanomedicine. The liposomal formulation protects DHA against chemical degradation and increases its local concentration within atherosclerotic lesions. Mechanistically, DHA liposomes are readily phagocytosed by activated macrophages, exert potent anti-inflammatory and antioxidant effects, and inhibit foam cell formation. Upon intravenous administration, DHA liposomes accumulate preferentially in atherosclerotic lesional macrophages and promote polarization of macrophages towards an anti-inflammatory M2 phenotype, resulting in attenuation of atherosclerosis progression in both ApoE-/- and Ldlr-/- experimental models. Plaque composition analysis demonstrates that liposomal DHA inhibits macrophage infiltration, reduces lipid deposition, and increases collagen content, thus improving the stability of atherosclerotic plaques against rupture. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) further reveals that DHA liposomes can partly restore the complex lipid profile of the plaques to that of early-stage plaques. In conclusion, DHA liposomes offer a promising approach for applying DHA to stabilize atherosclerotic plaques and attenuate atherosclerosis progression, thereby preventing atherosclerosis-related cardiovascular events.


Assuntos
Aterosclerose , Placa Aterosclerótica , Humanos , Placa Aterosclerótica/metabolismo , Ácidos Docosa-Hexaenoicos/uso terapêutico , Ácidos Docosa-Hexaenoicos/farmacologia , Lipossomos/uso terapêutico , Aterosclerose/metabolismo , Anti-Inflamatórios/uso terapêutico , Apolipoproteínas E/genética
3.
Int J Mol Sci ; 24(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36834844

RESUMO

Annexin A1 (ANXA1) is an endogenous protein, which plays a central function in the modulation of inflammation. While the functions of ANXA1 and its exogenous peptidomimetics, N-Acetyl 2-26 ANXA1-derived peptide (ANXA1Ac2-26), in the modulation of immunological responses of neutrophils and monocytes have been investigated in detail, their effects on the modulation of platelet reactivity, haemostasis, thrombosis, and platelet-mediated inflammation remain largely unknown. Here, we demonstrate that the deletion of Anxa1 in mice upregulates the expression of its receptor, formyl peptide receptor 2/3 (Fpr2/3, orthologue of human FPR2/ALX). As a result, the addition of ANXA1Ac2-26 to platelets exerts an activatory role in platelets, as characterised by its ability to increase the levels of fibrinogen binding and the exposure of P-selectin on the surface. Moreover, ANXA1Ac2-26 increased the development of platelet-leukocyte aggregates in whole blood. The experiments carried out using a pharmacological inhibitor (WRW4) for FPR2/ALX, and platelets isolated from Fpr2/3-deficient mice ascertained that the actions of ANXA1Ac2-26 are largely mediated through Fpr2/3 in platelets. Together, this study demonstrates that in addition to its ability to modulate inflammatory responses via leukocytes, ANXA1 modulates platelet function, which may influence thrombosis, haemostasis, and platelet-mediated inflammation under various pathophysiological settings.


Assuntos
Anexina A1 , Animais , Humanos , Camundongos , Anexina A1/metabolismo , Plaquetas/metabolismo , Inflamação/metabolismo , Neutrófilos/metabolismo , Peptídeos/farmacologia , Receptores de Formil Peptídeo/metabolismo , Receptores de Lipoxinas/metabolismo
4.
J Control Release ; 348: 938-950, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35732251

RESUMO

The therapeutic potential of antigen-specific regulatory T cells (Treg) has been extensively explored, leading to the development of several tolerogenic vaccines. Dexamethasone-antigen conjugates represent a prominent class of tolerogenic vaccines that enable coordinated delivery of antigen and dexamethasone to target immune cells. The importance of nonspecific albumin association towards the biodistribution of antigen-adjuvant conjugates has gained increasing attention, by which hydrophobic and electrostatic interactions govern the association capacity. Using an ensemble of computational and experimental techniques, we evaluate the impact of charged residues adjacent to the drug conjugation site in dexamethasone-antigen conjugates (Dex-K/E4-OVA323, K: lysine, E: glutamate) towards their albumin association capacity and induction of antigen-specific Treg. We find that Dex-K4-OVA323 possesses a higher albumin association capacity than Dex-E4-OVA323, leading to enhanced liver distribution and antigen-presenting cell uptake. Furthermore, using an OVA323-specific adoptive-transfer mouse model, we show that Dex-K4-OVA323 selectively upregulated OVA323-specific Treg cells, whereas Dex-E4-OVA323 exerted no significant effect on Treg cells. Our findings serve as a guide to optimize the functionality of dexamethasone-antigen conjugate amid switching vaccine epitope sequences. Moreover, our study demonstrates that moderating the residues adjacent to the conjugation sites can serve as an engineering approach for future peptide-drug conjugate development.


Assuntos
Linfócitos T Reguladores , Vacinas , Albuminas , Animais , Antígenos , Dexametasona , Camundongos , Peptídeos , Preparações Farmacêuticas , Distribuição Tecidual
5.
Food Funct ; 13(1): 76-90, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34882161

RESUMO

Blood outgrowth endothelial cells (BOECs) have received growing attention in relation to cardiovascular disease (CVD). However, the effect of diet intervention, a primary strategy for CVD prevention, on BOECs is not reported. This study aims to investigate the effect of following a healthy dietary pattern (HDP) with or without wolfberry consumption, healthy food with potential cardiovascular benefits, on the number and function of BOECs in middle-aged and older adults. Twenty-four subjects consumed either an HDP only (n = 9) or an HDP supplemented with 15 g day-1 wolfberries (n = 15) for 16 weeks. At pre- and post-intervention, vascular health biomarkers and composite CVD risk indicators were assessed. BOECs were derived from peripheral blood mononuclear cells and their angiogenic and migration activities were measured. Isolated BOECs have typical endothelial cobblestone morphology, express von Willebrand factor and KDR. Consuming an HDP improved the BOEC colony's growth rate, which was demonstrated by significant time effects in the colony's culture time between passages 1 and 2 (P = 0.038). Both interventions increased BOECs' tube formation capacity. Moreover, HDP intervention contributed to a time effect on BOEC migration activity (P = 0.040 for t1/2gap). Correlation analysis revealed that BOEC colony number was positively associated with blood pressure, atherogenic index, vascular age, and Framingham risk score. In conclusion, adherence to an HDP improved BOECs' function in middle-aged and older populations, while additional wolfberry consumption did not provide an enhanced effect. Our results provide mechanistic dissection on the beneficial effects on BOECs of dietary pattern modification.


Assuntos
Dieta Saudável , Células Progenitoras Endoteliais , Frutas , Fatores de Risco de Doenças Cardíacas , Lycium , Pressão Sanguínea/fisiologia , Movimento Celular/fisiologia , Células Cultivadas , Células Progenitoras Endoteliais/citologia , Células Progenitoras Endoteliais/fisiologia , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade
6.
Theranostics ; 11(19): 9243-9261, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34646369

RESUMO

The coagulation protein tissue factor (TF) regulates inflammation and angiogenesis via its cytoplasmic domain in infection, cancer and diabetes. While TF is highly abundant in the heart and is implicated in cardiac pathology, the contribution of its cytoplasmic domain to post-infarct myocardial injury and adverse left ventricular (LV) remodeling remains unknown. Methods: Myocardial infarction was induced in wild-type mice or mice lacking the TF cytoplasmic domain (TF∆CT) by occlusion of the left anterior descending coronary artery. Heart function was monitored with echocardiography. Heart tissue was collected at different time-points for histological, molecular and flow cytometry analysis. Results: Compared with wild-type mice, TF∆CT had a higher survival rate during a 28-day follow-up after myocardial infarction. Among surviving mice, TF∆CT mice had better cardiac function and less LV remodeling than wild-type mice. The overall improvement of post-infarct cardiac performance in TF∆CT mice, as revealed by speckle-tracking strain analysis, was attributed to reduced myocardial deformation in the peri-infarct region. Histological analysis demonstrated that TF∆CT hearts had in the infarct area greater proliferation of myofibroblasts and better scar formation. Compared with wild-type hearts, infarcted TF∆CT hearts showed less infiltration of proinflammatory cells with concomitant lower expression of protease-activated receptor-1 (PAR1) - Rac1 axis. In particular, infarcted TF∆CT hearts displayed markedly lower ratios of inflammatory M1 macrophages and reparative M2 macrophages (M1/M2). In vitro experiment with primary macrophages demonstrated that deletion of the TF cytoplasmic domain inhibited macrophage polarization toward the M1 phenotype. Furthermore, infarcted TF∆CT hearts presented markedly higher peri-infarct vessel density associated with enhanced endothelial cell proliferation and higher expression of PAR2 and PAR2-associated pro-angiogenic pathway factors. Finally, the overall cardioprotective effects observed in TF∆CT mice could be abolished by subcutaneously infusing a cocktail of PAR1-activating peptide and PAR2-inhibiting peptide via osmotic minipumps. Conclusions: Our findings demonstrate that the TF cytoplasmic domain exacerbates post-infarct cardiac injury and adverse LV remodeling via differential regulation of inflammation and angiogenesis. Targeted inhibition of the TF cytoplasmic domain-mediated intracellular signaling may ameliorate post-infarct LV remodeling without perturbing coagulation.


Assuntos
Infarto do Miocárdio/patologia , Tromboplastina/metabolismo , Remodelação Ventricular/fisiologia , Animais , Proliferação de Células/fisiologia , Inflamação/metabolismo , Ativação de Macrófagos/fisiologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miofibroblastos/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Patológica/prevenção & controle , Domínios Proteicos/fisiologia , Receptor PAR-1/metabolismo , Receptor PAR-2/metabolismo , Transdução de Sinais/fisiologia , Tromboplastina/fisiologia , Função Ventricular Esquerda/fisiologia
7.
Pharmaceutics ; 13(7)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34371743

RESUMO

Recently, bioinspired cell-derived nanovesicles (CDNs) have gained much interest in the field of nanomedicine due to the preservation of biomolecular structure characteristics derived from their parent cells, which impart CDNs with unique properties in terms of binding and uptake by target cells and intrinsic biological activities. Although the production of CDNs can be easily and reproducibly achieved with any kind of cell culture, application of CDNs for therapeutic purposes has been greatly hampered by their physical and chemical instability during long-term storage in aqueous dispersion. In the present study, we conceived a lyophilization approach that would preserve critical characteristics regarding stability (vesicles' size and protein content), structural integrity, and biological activity of CDNs for enabling long-term storage in freeze-dried form. Compared to the lyoprotectant sucrose, trehalose-lyoprotected CDNs showed significantly higher glass transition temperature and lower residual moisture content. As assessed by ATR-FTIR and far-UV circular dichroism, lyophilization in the presence of the lyoprotectant effectively maintained the secondary structure of cellular proteins. After reconstitution, lyoprotected CDNs were efficiently associated with HeLa cells, CT26 cells, and bone marrow-derived macrophages at a rate comparable to the freshly prepared CDNs. In vivo, both lyoprotected and freshly prepared CDNs, for the first time ever reported, targeted the injured heart, and exerted intrinsic cardioprotective effects within 24 h, attributable to the antioxidant capacity of CDNs in a myocardial ischemia/reperfusion injury animal model. Taken together, these results pave the way for further development of CDNs as cell-based therapeutics stabilized by lyophilization that enabled long-term storage while preserving their activity.

8.
Adv Mater ; 33(20): e2100012, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33837596

RESUMO

The COVID-19 pandemic, induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused great impact on the global economy and people's daily life. In the clinic, most patients with COVID-19 show none or mild symptoms, while approximately 20% of them develop severe pneumonia, multiple organ failure, or septic shock due to infection-induced cytokine release syndrome (the so-called "cytokine storm"). Neutralizing antibodies targeting inflammatory cytokines may potentially curb immunopathology caused by COVID-19; however, the complexity of cytokine interactions and the multiplicity of cytokine targets make attenuating the cytokine storm challenging. Nonspecific in vivo biodistribution and dose-limiting side effects further limit the broad application of those free antibodies. Recent advances in biomaterials and nanotechnology have offered many promising opportunities for infectious and inflammatory diseases. Here, potential mechanisms of COVID-19 cytokine storm are first discussed, and relevant therapeutic strategies and ongoing clinical trials are then reviewed. Furthermore, recent research involving emerging biomaterials for improving antibody-based and broad-spectrum cytokine neutralization is summarized. It is anticipated that this work will provide insights on the development of novel therapeutics toward efficacious management of COVID-19 cytokine storm and other inflammatory diseases.


Assuntos
Materiais Biocompatíveis/química , COVID-19/patologia , Síndrome da Liberação de Citocina/terapia , Citocinas/química , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/imunologia , Materiais Biocompatíveis/metabolismo , COVID-19/complicações , COVID-19/virologia , Síndrome da Liberação de Citocina/etiologia , Citocinas/imunologia , Citocinas/metabolismo , Vesículas Extracelulares/química , Humanos , Nanopartículas/química , Polímeros/química , SARS-CoV-2/isolamento & purificação
9.
Int J Mol Sci ; 20(13)2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31277271

RESUMO

Cardiovascular diseases (CVD) represent the leading cause of morbidity and mortality globally. The emerging role of extracellular vesicles (EVs) in intercellular communication has stimulated renewed interest in exploring the potential application of EVs as tools for diagnosis, prognosis, and therapy in CVD. The ubiquitous nature of EVs in biological fluids presents a technological advantage compared to current diagnostic tools by virtue of their notable stability. EV contents, such as proteins and microRNAs, represent specific signatures of cellular activation or injury. This feature positions EVs as an alternative source of biomarkers. Furthermore, their intrinsic activity and immunomodulatory properties offer EVs unique opportunities to act as therapeutic agents per se or to serve as drug delivery carriers by acting as miniaturized vehicles incorporating bioactive molecules. In this article, we aim to review the recent advances and applications of EV-based biomarkers and therapeutics. In addition, the potential of EVs as a drug delivery and theranostic platform for CVD will also be discussed.


Assuntos
Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/tratamento farmacológico , Vesículas Extracelulares , Animais , Biomarcadores/análise , Sistemas de Liberação de Medicamentos , Humanos
10.
Front Immunol ; 10: 1546, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354711

RESUMO

The global increase in autoimmunity, together with the emerging autoimmune-related side effects of cancer immunotherapy, have furthered a need for understanding of immune tolerance and activation. Systemic lupus erythematosus (SLE) is the archetypical autoimmune disease, affecting multiple organs, and tissues. Studying SLE creates knowledge relevant not just for autoimmunity, but the immune system in general. Murine models and patient studies have provided increasing evidence for the innate immune toll like receptor-7 (TLR7) in disease initiation and progression. Here, we demonstrated that the kinase activity of the TLR7-downstream signaling molecule, interleukin-1 receptor associated kinase 4 (IRAK4), is essential for mild and severe autoimmune traits of the Sle1 and Sle1-TLR7 transgenic (Sle1Tg7) murine models, respectively. Elimination of IRAK4 signaling prevented all pathological traits associated with murine lupus, including splenomegaly with leukocyte expansion, detectable circulating antinuclear antibodies and glomerulonephritis, in both Sle1 and Sle1Tg7 mice. The expansion of germinal center B cells and increased effector memory T cell phenotypes that are typical of lupus-prone strains, were also prevented with IRAK4 kinase elimination. Analysis of renal leukocyte infiltrates confirmed our earlier findings of an expanded conventional dendritic cell (cDC) within the kidneys of nephritic mice, and this was prevented with IRAK4 kinase elimination. Analysis of TLR7 at the protein level revealed that the expression in immune cells is dependent on the TLR7-transgene itself and/or autoimmune disease factors in a cell-specific manner. Increased TLR7 protein expression in renal macrophages and cDCs correlated with disease parameters such as blood urea nitrogen (BUN) levels and the frequency of leukocytes infiltrating the kidney. These findings suggest that controlling the level of TLR7 or downstream signaling within myeloid populations may prevent chronic inflammation and severe nephritis.


Assuntos
Células Dendríticas/imunologia , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Rim/patologia , Leucócitos/fisiologia , Lúpus Eritematoso Sistêmico/metabolismo , Nefrite Lúpica/metabolismo , Macrófagos/imunologia , Receptor 7 Toll-Like/metabolismo , Animais , Anticorpos Antinucleares/sangue , Movimento Celular , Modelos Animais de Doenças , Glomerulonefrite , Humanos , Imunidade Inata , Quinases Associadas a Receptores de Interleucina-1/genética , Rim/metabolismo , Nefrite Lúpica/genética , Camundongos , Camundongos Transgênicos , Especificidade de Órgãos , Fator de Transcrição 1 de Leucemia de Células Pré-B/genética , Fator de Transcrição 1 de Leucemia de Células Pré-B/metabolismo , Transdução de Sinais , Receptor 7 Toll-Like/genética
11.
Cardiovasc Res ; 115(12): 1791-1803, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30830156

RESUMO

AIMS: The Toll-like receptor 7 (TLR7) is an intracellular innate immune receptor activated by nucleic acids shed from dying cells leading to activation of the innate immune system. Since innate immune system activation is involved in the response to myocardial infarction (MI), this study aims to identify if TLR7 is involved in post-MI ischaemic injury and adverse remodelling after MI. METHODS AND RESULTS: TLR7 involvement in MI was investigated in human tissue from patients with ischaemic heart failure, as well as in a mouse model of permanent left anterior descending artery occlusion in C57BL/6J wild type and TLR7 deficient (TLR7-/-) mice. TLR7 expression was up-regulated in human and mouse ischaemic myocardium after MI. Compared to wild type mice, TLR7-/- mice had less acute cardiac rupture associated with blunted activation of matrix metalloproteinase 2, increased expression of tissue inhibitor of metalloproteinase 1, recruitment of more myofibroblasts, and the formation of a myocardial scar with higher collagen fibre density. Furthermore, inflammatory cell influx and inflammatory cytokine expression post-MI were reduced in the TLR7-/- heart. During a 28-day follow-up after MI, TLR7 deficiency resulted in less chronic adverse left ventricular remodelling and better cardiac function. Bone marrow (BM) transplantation experiments showed that TLR7 deficiency in BM-derived cells preserved cardiac function after MI. CONCLUSIONS: In acute MI, TLR7 mediates the response to acute cardiac injury and chronic remodelling probably via modulation of post-MI scar formation and BM-derived inflammatory infiltration of the myocardium.


Assuntos
Glicoproteínas de Membrana/deficiência , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Receptor 7 Toll-Like/deficiência , Disfunção Ventricular Esquerda/metabolismo , Função Ventricular Esquerda , Remodelação Ventricular , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Feminino , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Glicoproteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/imunologia , Miocárdio/patologia , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Transdução de Sinais , Receptor 7 Toll-Like/genética , Receptor 7 Toll-Like/metabolismo , Disfunção Ventricular Esquerda/imunologia , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/prevenção & controle
12.
Cytometry A ; 95(3): 268-278, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30549398

RESUMO

Neutrophil extracellular traps (NETs) are web-like structures composed of decondensed chromatin and antimicrobial proteins that are released into the extracellular space during microbial infections. This active cell death program is known as NETosis. To date, florescence microscopy is the widely accepted method for visualization and quantification of NETs. However, this method is subjective, time consuming and yields low numbers of analyzed polymorphonuclear cells (PMNs) per sample. Increasing interest has emerged on the identification of NETs using flow cytometry techniques. However, flow cytometry analysis of NETs requires particular precautions for sample preparation to obtain reproducible data. Herein, we describe a flow cytometry-based assay for high-throughput detection and quantification of NETosis in mixed cell populations. We used fluorescent-labeled antibodies against cell markers on PMNs together with a combination of nucleic acid stains to measure NETosis in whole blood (WB) and purified PMNs. Using plasma membrane-impermeable DNA-binding dye, SYTOX Orange (SO), we found that cell-appendant DNA of NETting PMNs were positive for SO and DAPI. The combination of optimally diluted antibody and nucleic acid dyes required no washing and yielded low background fluorescence. Significant correlations were found for NETosis from WB and purified PMNs. We then validated the assay by comparing with time-lapse live cell fluorescence microscopy and determined very good intraassay and interassay variances. The assay was then applied to a disease associated with NETosis, systemic lupus erythematosus (SLE). We examined PMA-induced NETosis in peripheral PMNs from SLE patients and controls and in bone marrow PMNs from multiple murine models. In summary, this assay is observer-independent and allows for rapid assessment of a large number of PMNs per sample. Use of this assay does not require sophisticated microscopic equipment like imaging flow cytometers and may be a starting point to analyze extracellular trap formation from immune cells other than PMNs. © 2018 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.


Assuntos
Armadilhas Extracelulares/metabolismo , Citometria de Fluxo/métodos , Imunofluorescência/métodos , Microscopia de Fluorescência/métodos , Neutrófilos/metabolismo , Animais , Células da Medula Óssea/metabolismo , DNA/análise , DNA/química , Modelos Animais de Doenças , Armadilhas Extracelulares/química , Feminino , Ensaios de Triagem em Larga Escala , Humanos , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Morte Celular Regulada/efeitos dos fármacos , Morte Celular Regulada/genética
13.
Front Pharmacol ; 9: 1282, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30498445

RESUMO

Influenza A viruses (IAVs) are important human respiratory pathogens which cause seasonal or periodic endemic infections. IAV can result in severe or fatal clinical complications including pneumonia and respiratory distress syndrome. Treatment of IAV infections is complicated because the virus can evade host immunity through antigenic drifts and antigenic shifts, to establish infections making new treatment options desirable. Annexins (ANXs) are a family of calcium and phospholipid binding proteins with immunomodulatory roles in viral infections, lung injury, and inflammation. A current understanding of the role of ANXs in modulating IAV infection and host responses will enable the future development of more effective antiviral therapies. This review presents a comprehensive understanding of the advances made in the field of ANXs, in particular, ANXA1 and IAV research and highlights the importance of ANXs as a suitable target for IAV therapy.

14.
Arthritis Rheumatol ; 70(10): 1597-1609, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29687651

RESUMO

OBJECTIVE: Toll-like receptors (TLRs) 7 and 9 are important innate signaling molecules with opposing roles in the development and progression of systemic lupus erythematosus (SLE). While multiple studies support the notion of a dependency on TLR-7 for disease development, genetic ablation of TLR-9 results in severe disease with glomerulonephritis (GN) by a largely unknown mechanism. This study was undertaken to examine the suppressive role of TLR-9 in the development of severe lupus in a mouse model. METHODS: We crossed Sle1 lupus-prone mice with TLR-9-deficient mice to generate Sle1TLR-9-/- mice. Mice ages 4.5-6.5 months were evaluated for severe autoimmunity by assessing splenomegaly, GN, immune cell populations, autoantibody and total Ig profiles, kidney dendritic cell (DC) function, and TLR-7 protein expression. Mice ages 8-10 weeks were used for functional B cell studies, Ig profiling, and determination of TLR-7 expression. RESULTS: Sle1TLR-9-/- mice developed severe disease similar to TLR-9-deficient MRL and Nba2 models. Sle1TLR-9-/- mouse B cells produced more class-switched antibodies, and the autoantibody repertoire was skewed toward RNA-containing antigens. GN in these mice was associated with DC infiltration, and purified Sle1TLR-9-/- mouse renal DCs were more efficient at TLR-7-dependent antigen presentation and expressed higher levels of TLR-7 protein. Importantly, this increase in TLR-7 expression occurred prior to disease development, indicating a role in the initiation stages of tissue destruction. CONCLUSION: The increase in TLR-7-reactive immune complexes, and the concomitant enhanced expression of their receptor, promotes inflammation and disease in Sle1TLR9-/- mice.


Assuntos
Lúpus Eritematoso Sistêmico/imunologia , Nefrite Lúpica/imunologia , Receptor 7 Toll-Like/imunologia , Receptor Toll-Like 9/deficiência , Regulação para Cima/imunologia , Animais , Antígenos/imunologia , Modelos Animais de Doenças , Camundongos , RNA/imunologia , Receptor Toll-Like 9/imunologia
15.
Sci Rep ; 7(1): 17925, 2017 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-29263330

RESUMO

Macrophages are potent immune cells with well-established roles in the response to stress, injury, infection and inflammation. The classically activated macrophages (M1) are induced by lipopolysaccharide (LPS) and express a wide range of pro-inflammatory genes. M2 macrophages are induced by T helper type 2 cytokines such as interleukin-4 (IL4) and express high levels of anti-inflammatory and tissue repair genes. The strong association between macrophages and tumour cells as well as the high incidences of leukocyte infiltration in solid tumours have contributed to the discovery that tumour-associated macrophages (TAMs) are key to tumour progression. Here, we investigated the role of Annexin A1 (ANXA1), a well characterized immunomodulatory protein on macrophage polarization and the interaction between macrophages and breast cancer cells. Our results demonstrate that ANXA1 regulates macrophage polarization and activation. ANXA1 can act dually as an endogenous signalling molecule or as a secreted mediator which acts via its receptor, FPR2, to promote macrophage polarization. Furthermore, ANXA1 deficient mice exhibit reduced tumour growth and enhanced survival in vivo, possibly due to increased M1 macrophages within the tumor microenvironment. These results provide new insights into the molecular mechanisms of macrophage polarization with therapeutic potential to suppress breast cancer growth and metastasis.


Assuntos
Anexina A1/metabolismo , Movimento Celular , Proliferação de Células , Macrófagos/imunologia , Neoplasias Mamárias Animais/patologia , Microambiente Tumoral/imunologia , Animais , Anexina A1/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Neoplasias Mamárias Animais/imunologia , Neoplasias Mamárias Animais/metabolismo , Camundongos , NF-kappa B/metabolismo , Receptores de Formil Peptídeo/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas
16.
Rheumatology (Oxford) ; 56(suppl_1): i55-i66, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28375453

RESUMO

SLE is a chronic autoimmune disease caused by perturbations of the immune system. The clinical presentation is heterogeneous, largely because of the multiple genetic and environmental factors that contribute to disease initiation and progression. Over the last 60 years, there have been a number of significant leaps in our understanding of the immunological mechanisms driving disease processes. We now know that multiple leucocyte subsets, together with inflammatory cytokines, chemokines and regulatory mediators that are normally involved in host protection from invading pathogens, contribute to the inflammatory events leading to tissue destruction and organ failure. In this broad overview, we discuss the main pathways involved in SLE and highlight new findings. We describe the immunological changes that characterize this form of autoimmunity. The major leucocytes that are essential for disease progression are discussed, together with key mediators that propagate the immune response and drive the inflammatory response in SLE.


Assuntos
Autoimunidade/imunologia , Linfócitos B/imunologia , Citocinas/imunologia , Meio Ambiente , Inflamação/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Autoimunidade/genética , Predisposição Genética para Doença , Humanos , Inflamação/genética , Lúpus Eritematoso Sistêmico/genética , Tolerância a Antígenos Próprios/genética , Tolerância a Antígenos Próprios/imunologia
17.
Asian Pac J Cancer Prev ; 16(2): 689-92, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25684509

RESUMO

BACKGROUND: Incorporation of molecular analysis of the epidermal growth factor receptor (EGFR) gene into routine clinical practice has shown great promise to provide personalized therapy of the non-small cell lung cancer (NSCLC) in the developed world. However, the genetic testing of EGFR mutations has not yet become routine clinical practice in territories remote from the central regions of Russia. Therefore, we aimed to study the frequency of major types of activating mutations of the EGFR gene in NSCLC patients residing in West Siberia. MATERIALS AND METHODS: We examined EGFR mutations in exons 19 and 21 in 147 NSCLC patients (excluding squamous cell lung carcinomas) by real time polymerase chain reaction. RESULTS: EGFR mutations were detected in 28 of the 147 (19%) patients. There were 19 (13%) cases with mutations in exon 19 and 9 cases (6%) in exon 21. Mutations were more frequently observed in women (42%, p=0.000) than in men (1%). A significantly higher incidence of EGFR mutations was observed in bronchioloalveolar carcinomas (28%, p=0.019) and in adenocarcinomas (21%, p=0.024) than in large cell carcinomas, mixed adenocarcinomas, and NOS (4%). The EGFR mutation rate was much higher in never-smokers than in smokers: 38% vs. 3% (p=0.000). The frequency of EGFR mutations in the Kemerovo and Tomsk regions was 19%. CONCLUSIONS: The incorporation of molecular analysis of the EGFR gene into routine clinical practice will allow clinicians to provide personalised therapy, resulting in a significant increase in survival rates and improvement in life quality of advanced NSCLC patients.


Assuntos
Adenocarcinoma Bronquioloalveolar/genética , Carcinoma de Células Grandes/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma de Células Escamosas/genética , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Mutação/genética , Adenocarcinoma Bronquioloalveolar/patologia , Adulto , Idoso , Carcinoma de Células Grandes/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Feminino , Seguimentos , Testes Genéticos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase , Prognóstico , Federação Russa
18.
Pharmacol Biochem Behav ; 90(4): 712-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18582921

RESUMO

The lupane type pentacyclic triterpenes: lupeol, betulin, and betulinic acid are widely distributed natural compounds. Recently, pharmaceutical compositions from plant extracts (family Marcgraviaceae) containing betulinic acid, have been patented as anxiolytic remedies. To extend our knowledge of the CNS effects of the triterpenes, we suggest here that the chemically related lupeol, betulin and betulinic acid may interact with the brain neurotransmitter gamma-aminobutyric acid (GABA) receptors in vitro and in vivo. Using radioligand receptor-binding assay, we showed that only betulin bound to the GABA(A)-receptor sites in mice brain in vitro and antagonised the GABA(A)-receptor antagonist bicuculline-induced seizures in mice after intracisternal and intraperitoneal administration. Neither betulinic acid nor lupeol bound to GABA(A) receptor nor did they inhibit bicuculline-induced seizures in vivo. These findings demonstrate for the first time the CNS effects of betulin in vivo, and they also show distinct GABA(A)-receptor-related properties of lupane type triterpenes. These findings may open new avenues in understanding the central effects of betulin, and they also indicate possibilities for novel drug design on the basis of betulin structure.


Assuntos
Anticonvulsivantes/farmacologia , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Receptores de GABA/metabolismo , Triterpenos/metabolismo , Triterpenos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Bicuculina/farmacologia , Flunitrazepam/metabolismo , Moduladores GABAérgicos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Tono Muscular/efeitos dos fármacos , Triterpenos Pentacíclicos , Equilíbrio Postural/efeitos dos fármacos , Convulsões/induzido quimicamente , Convulsões/psicologia , Ácido gama-Aminobutírico/metabolismo , Ácido Betulínico
19.
Eur J Pharmacol ; 583(1): 128-34, 2008 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-18275958

RESUMO

Phenibut (3-phenyl-4-aminobutyric acid) is a GABA (gamma-aminobutyric acid)-mimetic psychotropic drug which is clinically used in its racemic form. The aim of the present study was to compare the effects of racemic phenibut and its optical isomers in pharmacological tests and GABAB receptor binding studies. In pharmacological tests of locomotor activity, antidepressant and pain effects, S-phenibut was inactive in doses up to 500 mg/kg. In contrast, R-phenibut turned out to be two times more potent than racemic phenibut in most of the tests. In the forced swimming test, at a dose of 100 mg/kg only R-phenibut significantly decreased immobility time. Both R-phenibut and racemic phenibut showed analgesic activity in the tail-flick test with R-phenibut being slightly more active. An GABAB receptor-selective antagonist (3-aminopropyl)(diethoxymethyl)phosphinic acid (CGP35348) inhibited the antidepressant and antinociceptive effects of R-phenibut, as well as locomotor depressing activity of R-phenibut in open field test in vivo. The radioligand binding experiments using a selective GABAB receptor antagonist [3H]CGP54626 revealed that affinity constants for racemic phenibut, R-phenibut and reference GABA-mimetic baclofen were 177+/-2, 92+/-3, 6.0+/-1 microM, respectively. We conclude that the pharmacological activity of racemic phenibut relies on R-phenibut and this correlates to the binding affinity of enantiomers of phenibut to the GABAB receptor.


Assuntos
Psicotrópicos/farmacologia , Ácido gama-Aminobutírico/análogos & derivados , Analgésicos/farmacologia , Animais , Antidepressivos/farmacologia , Conflito Psicológico , Depressão/psicologia , Agonistas GABAérgicos/farmacologia , Antagonistas GABAérgicos/farmacologia , Temperatura Alta , Masculino , Camundongos , Camundongos Endogâmicos CBA , Camundongos Endogâmicos ICR , Atividade Motora/efeitos dos fármacos , Força Muscular/efeitos dos fármacos , Compostos Organofosforados/farmacologia , Medição da Dor/efeitos dos fármacos , Equilíbrio Postural/efeitos dos fármacos , Desempenho Psicomotor/efeitos dos fármacos , Psicotrópicos/administração & dosagem , Psicotrópicos/química , Tempo de Reação/efeitos dos fármacos , Receptores de GABA-B/efeitos dos fármacos , Estereoisomerismo , Natação/psicologia , Ácido gama-Aminobutírico/administração & dosagem , Ácido gama-Aminobutírico/química , Ácido gama-Aminobutírico/farmacologia
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