Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
Immunity ; 57(1): 52-67.e10, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38091995

RESUMO

The regulation of polymorphonuclear leukocyte (PMN) function by mechanical forces encountered during their migration across restrictive endothelial cell junctions is not well understood. Using genetic, imaging, microfluidic, and in vivo approaches, we demonstrated that the mechanosensor Piezo1 in PMN plasmalemma induced spike-like Ca2+ signals during trans-endothelial migration. Mechanosensing increased the bactericidal function of PMN entering tissue. Mice in which Piezo1 in PMNs was genetically deleted were defective in clearing bacteria, and their lungs were predisposed to severe infection. Adoptive transfer of Piezo1-activated PMNs into the lungs of Pseudomonas aeruginosa-infected mice or exposing PMNs to defined mechanical forces in microfluidic systems improved bacterial clearance phenotype of PMNs. Piezo1 transduced the mechanical signals activated during transmigration to upregulate nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4, crucial for the increased PMN bactericidal activity. Thus, Piezo1 mechanosensing of increased PMN tension, while traversing the narrow endothelial adherens junctions, is a central mechanism activating the host-defense function of transmigrating PMNs.


Assuntos
Movimento Celular , Pulmão , Mecanotransdução Celular , Neutrófilos , Animais , Camundongos , Membrana Celular , Canais Iônicos/genética , Neutrófilos/metabolismo , Neutrófilos/microbiologia , Atividade Bactericida do Sangue/genética , Mecanotransdução Celular/genética
2.
Nat Immunol ; 21(11): 1430-1443, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32839607

RESUMO

Macrophages demonstrate remarkable plasticity that is essential for host defense and tissue repair. The tissue niche imprints macrophage identity, phenotype and function. The role of vascular endothelial signals in tailoring the phenotype and function of tissue macrophages remains unknown. The lung is a highly vascularized organ and replete with a large population of resident macrophages. We found that, in response to inflammatory injury, lung endothelial cells release the Wnt signaling modulator Rspondin3, which activates ß-catenin signaling in lung interstitial macrophages and increases mitochondrial respiration by glutaminolysis. The generated tricarboxylic acid cycle intermediate α-ketoglutarate, in turn, serves as the cofactor for the epigenetic regulator TET2 to catalyze DNA hydroxymethylation. Notably, endothelial-specific deletion of Rspondin3 prevented the formation of anti-inflammatory interstitial macrophages in endotoxemic mice and induced unchecked severe inflammatory injury. Thus, the angiocrine-metabolic-epigenetic signaling axis specified by the endothelium is essential for reprogramming interstitial macrophages and dampening inflammatory injury.


Assuntos
Reprogramação Celular , Metabolismo Energético , Epigênese Genética , Inflamação/etiologia , Inflamação/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Trombospondinas/genética , Animais , Biomarcadores , Reprogramação Celular/genética , Reprogramação Celular/imunologia , Modelos Animais de Doenças , Suscetibilidade a Doenças , Imunofluorescência , Inflamação/patologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Trombospondinas/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(38): e2205454119, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36095190

RESUMO

Trastuzumab is the first-line therapy for human epidermal growth factor receptor 2-positive (HER2+) breast cancer, but often patients develop acquired resistance. Although other agents are in clinical use to treat trastuzumab-resistant (TR) breast cancer; still, the patients develop recurrent metastatic disease. One of the primary mechanisms of acquired resistance is the shedding/loss of the HER2 extracellular domain, where trastuzumab binds. We envisioned any new agent acting downstream of the HER2 should overcome trastuzumab resistance. The mixed lineage kinase 3 (MLK3) activation by trastuzumab is necessary for promoting cell death in HER2+ breast cancer. We designed nanoparticles loaded with MLK3 agonist ceramide (PPP-CNP) and tested their efficacy in sensitizing TR cell lines, patient-derived organoids, and patient-derived xenograft (PDX). The PPP-CNP activated MLK3, its downstream JNK kinase activity, and down-regulated AKT pathway signaling in TR cell lines and PDX. The activation of MLK3 and down-regulation of AKT signaling by PPP-CNP induced cell death and inhibited cellular proliferation in TR cells and PDX. The apoptosis in TR cells was dependent on increased CD70 protein expression and caspase-9 and caspase-3 activities by PPP-CNP. The PPP-CNP treatment alike increased the expression of CD70, CD27, cleaved caspase-9, and caspase-3 with a concurrent tumor burden reduction of TR PDX. Moreover, the expressions of CD70 and ceramide levels were lower in TR than sensitive HER2+ human breast tumors. Our in vitro and preclinical animal models suggest that activating the MLK3-CD70 axis by the PPP-CNP could sensitize/overcome trastuzumab resistance in HER2+ breast cancer.


Assuntos
Antineoplásicos Imunológicos , Neoplasias da Mama , Ligante CD27 , Resistencia a Medicamentos Antineoplásicos , MAP Quinase Quinase Quinases , Nanopartículas , Trastuzumab , Animais , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Ligante CD27/metabolismo , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Ceramidas/química , Feminino , Humanos , MAP Quinase Quinase Quinases/metabolismo , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor ErbB-2/análise , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , MAP Quinase Quinase Quinase 11 Ativada por Mitógeno
4.
Am J Pathol ; 192(12): 1779-1794, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36063899

RESUMO

The observation that diabetic retinopathy (DR) typically takes decades to develop suggests the existence of an endogenous system that protects from diabetes-induced damage. To investigate the existance of such a system, primary human retinal endothelial cells were cultured in either normal glucose (5 mmol/L) or high glucose (30 mmol/L; HG). Prolonged exposure to HG was beneficial instead of detrimental. Although tumor necrosis factor-α-induced expression of vascular cell adhesion molecule 1 and intercellular adhesion molecule 1 was unaffected after 1 day of HG, it waned as the exposure to HG was extended. Similarly, oxidative stress-induced death decreased with prolonged exposure to HG. Furthermore, mitochondrial functionality, which was compromised by 1 day of HG, was improved by 10 days of HG, and this change required increased clearance of damaged mitochondria (mitophagy). Finally, antagonizing mitochondrial dynamics compromised the cells' ability to endure HG: susceptibility to cell death increased, and basal barrier function and responsiveness to vascular endothelial growth factor deteriorated. These observations indicate the existence of an endogenous system that protects human retinal endothelial cells from the deleterious effects of HG. Hyperglycemia-induced mitochondrial adaptation is a plausible contributor to the mechanism responsible for the delayed onset of DR; loss of hyperglycemia-induced mitochondrial adaptation may set the stage for the development of DR.


Assuntos
Retinopatia Diabética , Hiperglicemia , Humanos , Mitofagia , Células Endoteliais/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Glucose/metabolismo , Hiperglicemia/patologia , Retinopatia Diabética/patologia
5.
J Cell Sci ; 133(9)2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32409569

RESUMO

The sex-biased disease pulmonary arterial hypertension (PAH) is characterized by the proliferation and overgrowth of dysfunctional pulmonary artery endothelial cells (PAECs). During inflammation associated with PAH, granzyme B cleaves intersectin-1 to produce N-terminal (EHITSN) and C-terminal (SH3A-EITSN) protein fragments. In a murine model of PAH, EHITSN triggers plexiform arteriopathy via p38-ELK1-c-Fos signaling. The SH3A-EITSN fragment also influences signaling, having dominant-negative effects on ERK1 and ERK2 (also known as MAPK3 and MAPK1, respectively). Using PAECs engineered to express tagged versions of EHITSN and SH3A-EITSN, we demonstrate that the two ITSN fragments increase both p38-ELK1 activation and the ratio of p38 to ERK1 and ERK2 activity, leading to PAEC proliferation, with female cells being more responsive than male cells. Furthermore, expression of EHITSN substantially upregulates the expression and activity of the long non-coding RNA Xist in female PAECs, which in turn upregulates the X-linked gene ELK1 and represses expression of krüppel-like factor 2 (KLF2). These events are recapitulated by the PAECs of female idiopathic PAH patients, and may account for their proliferative phenotype. Thus, upregulation of Xist could be an important factor in explaining sexual dimorphism in the proliferative response of PAECs and the imbalanced sex ratio of PAH.


Assuntos
Hipertensão Pulmonar , Artéria Pulmonar , Animais , Proliferação de Células , Células Cultivadas , Células Endoteliais , Feminino , Humanos , Masculino , Camundongos , Caracteres Sexuais
6.
PNAS Nexus ; 3(2): pgae038, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38344009

RESUMO

To date, there are no efficacious translational solutions for end-stage urinary bladder dysfunction. Current surgical strategies, including urinary diversion and bladder augmentation enterocystoplasty (BAE), utilize autologous intestinal segments (e.g. ileum) to increase bladder capacity to protect renal function. Considered the standard of care, BAE is fraught with numerous short- and long-term clinical complications. Previous clinical trials employing tissue engineering approaches for bladder tissue regeneration have also been unable to translate bench-top findings into clinical practice. Major obstacles still persist that need to be overcome in order to advance tissue-engineered products into the clinical arena. These include scaffold/bladder incongruencies, the acquisition and utility of appropriate cells for anatomic and physiologic tissue recapitulation, and the choice of an appropriate animal model for testing. In this study, we demonstrate that the elastomeric, bladder biomechanocompatible poly(1,8-octamethylene-citrate-co-octanol) (PRS; synthetic) scaffold coseeded with autologous bone marrow-derived mesenchymal stem cells and CD34+ hematopoietic stem/progenitor cells support robust long-term, functional bladder tissue regeneration within the context of a clinically relevant baboon bladder augmentation model simulating bladder trauma. Partially cystectomized baboons were independently augmented with either autologous ileum or stem-cell-seeded small-intestinal submucosa (SIS; a commercially available biological scaffold) or PRS grafts. Stem-cell synergism promoted functional trilayer bladder tissue regeneration, including whole-graft neurovascularization, in both cell-seeded grafts. However, PRS-augmented animals demonstrated fewer clinical complications and more advantageous tissue characterization metrics compared to ileum and SIS-augmented animals. Two-year study data demonstrate that PRS/stem-cell-seeded grafts drive bladder tissue regeneration and are a suitable alternative to BAE.

7.
J Exp Med ; 220(11)2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37615937

RESUMO

Recent studies suggest that training of innate immune cells such as tissue-resident macrophages by repeated noxious stimuli can heighten host defense responses. However, it remains unclear whether trained immunity of tissue-resident macrophages also enhances injury resolution to counterbalance the heightened inflammatory responses. Here, we studied lung-resident alveolar macrophages (AMs) prechallenged with either the bacterial endotoxin or with Pseudomonas aeruginosa and observed that these trained AMs showed greater resilience to pathogen-induced cell death. Transcriptomic analysis and functional assays showed greater capacity of trained AMs for efferocytosis of cellular debris and injury resolution. Single-cell high-dimensional mass cytometry analysis and lineage tracing demonstrated that training induces an expansion of a MERTKhiMarcohiCD163+F4/80low lung-resident AM subset with a proresolving phenotype. Reprogrammed AMs upregulated expression of the efferocytosis receptor MERTK mediated by the transcription factor KLF4. Adoptive transfer of these trained AMs restricted inflammatory lung injury in recipient mice exposed to lethal P. aeruginosa. Thus, our study has identified a subset of tissue-resident trained macrophages that prevent hyperinflammation and restore tissue homeostasis following repeated pathogen challenges.


Assuntos
Macrófagos Alveolares , Imunidade Treinada , Animais , Camundongos , Transferência Adotiva , c-Mer Tirosina Quinase/genética , Fagocitose
8.
Clin Immunol ; 145(3): 209-23, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23110942

RESUMO

Previous studies have reported alterations in numbers or function of regulatory T (Treg) cells in myasthenia gravis (MG) patients, but published results have been inconsistent, likely due to the isolation of heterogenous "Treg" populations. In this study, we used surface CD4, CD25(high), and CD127(low/-) expression to isolate a relatively pure population of Tregs, and established that there was no alteration in the relative numbers of Tregs within the peripheral T cell pool in MG patients. In vitro proliferation assays, however, demonstrated that Treg-mediated suppression of responder T (Tresp) cells was impaired in MG patients and was associated with a reduced expression of FOXP3 in isolated Tregs. Suppression of both polyclonal and AChR-activated Tresp cells from MG patients could be restored using Tregs isolated from healthy controls, indicating that the defect in immune regulation in MG is primarily localized to isolated Treg cells, and revealing a potential novel therapeutic target.


Assuntos
Miastenia Gravis/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Células Apresentadoras de Antígenos/imunologia , Antígenos CD4/metabolismo , Estudos de Casos e Controles , Separação Celular , Citocinas/biossíntese , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Humanos , Técnicas In Vitro , Interleucina-10/biossíntese , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/genética , Miastenia Gravis/metabolismo , Receptores Colinérgicos/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/metabolismo , Adulto Jovem
9.
J Long Term Eff Med Implants ; 32(1): 25-32, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35377991

RESUMO

Implant therapy is a treatment option to ensure prosthesis survival rate and it is also done as a fixed dental prosthesis for replacing single and multiunit gaps. Posterior maxilla often has insufficient bone quality and quantity; for this reason it makes implant placement challenging in the site. Posterior edentulous maxilla presents special challenges to implant surgeons that are unique to this region compared to other regions of the maxilla. Thus, the aim of this study is to determine the common implant dimensions used in posterior maxilla. Completed case sheets were collected from a private dental hospital software system. Case sheets were taken from June 2019 to March 2020. Data was retrieved and evaluated by two reviewers. The parameters taken were patients, age groups, gender, teeth indicated for implants (maxillary premolars and molars), implant height, and implant width. Two-hundred fifty-four implants have been placed on the posterior maxilla of which 139 were premolars and 115 were molars. There was no statistical significance between the implants placed in both males and females (p value: 0.274). Between the age groups, the highest number of implants was seen in 41-60 years (n = 146) followed by 17-40 years (n = 78) and finally > 61 years (n = 30). The p value was 0.000, which was statistically significant. Various implant sizes for posterior maxilla have been introduced due to its challenging site. Thus in our study, we can see there is a difference in sizes for premolars and molars. Implant dimensions with increased height are used in the premolars compared to the molars. Implant dimensions with increased width are used in the molars compared to the premolars. In general, implant width and implant height can range from 3.6 to 4.5 mm and implant height ranging from 9.50 to 12.00 mm.


Assuntos
Maxila , Próteses e Implantes , Adulto , Feminino , Humanos , Masculino , Maxila/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
Pulm Circ ; 12(1): e12014, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35506070

RESUMO

In the lung, communication between pulmonary vascular endothelial cells (PVEC) and pulmonary artery smooth muscle cells (PASMC) is essential for the maintenance of vascular homeostasis. In pulmonary hypertension (PH), the derangement in their cell-cell communication plays a major role in the pathogenesis of pulmonary vascular remodeling. In this study, we focused on the role of PVEC-derived extracellular vesicles (EV), specifically their microRNA (miRNA, miR-) cargo, in the regulation of PASMC proliferation and vascular remodeling in PH. We found that the amount of pro-proliferative miR-210-3p was increased in PVEC-derived EV in hypoxia (H-EV), which contributes to the H-EV-induced proliferation of PASMC and the development of PH.

11.
Mol Ther Nucleic Acids ; 29: 204-216, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-35892089

RESUMO

MicroRNAs (miRNA, miR-) play important roles in disease development. In this study, we identified an anti-proliferative miRNA, miR-212-5p, that is induced in pulmonary artery smooth muscle cells (PASMCs) and lungs of pulmonary hypertension (PH) patients and rodents with experimental PH. We found that smooth muscle cell (SMC)-specific knockout of miR-212-5p exacerbated hypoxia-induced pulmonary vascular remodeling and PH in mice, suggesting that miR-212-5p may be upregulated in PASMCs to act as an endogenous inhibitor of PH, possibly by suppressing PASMC proliferation. Extracellular vesicles (EVs) have been shown recently to be promising drug delivery tools for disease treatment. We generated endothelium-derived EVs with an enriched miR-212-5p load, 212-eEVs, and found that they significantly attenuated hypoxia-induced PH in mice and Sugen/hypoxia-induced severe PH in rats, providing proof of concept that engineered endothelium-derived EVs can be used to deliver miRNA into lungs for treatment of severe PH.

12.
ACS Nano ; 16(3): 4084-4101, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35230826

RESUMO

The complex involvement of neutrophils in inflammatory diseases makes them intriguing but challenging targets for therapeutic intervention. Here, we tested the hypothesis that varying endocytosis capacities would delineate functionally distinct neutrophil subpopulations that could be specifically targeted for therapeutic purposes. By using uniformly sized (∼120 nm in diameter) albumin nanoparticles (ANP) to characterize mouse neutrophils in vivo, we found two subsets of neutrophils, one that readily endocytosed ANP (ANPhigh neutrophils) and another that failed to endocytose ANP (ANPlow population). These ANPhigh and ANPlow subsets existed side by side simultaneously in bone marrow, peripheral blood, spleen, and lungs, both under basal conditions and after inflammatory challenge. Human peripheral blood neutrophils showed a similar duality. ANPhigh and ANPlow neutrophils had distinct cell surface marker expression and transcriptomic profiles, both in naive mice and in mice after endotoxemic challenge. ANPhigh and ANPlow neutrophils were functionally distinct in their capacities to kill bacteria and to produce inflammatory mediators. ANPhigh neutrophils produced inordinate amounts of reactive oxygen species and inflammatory chemokines and cytokines. Targeting this subset with ANP loaded with the drug piceatannol, a spleen tyrosine kinase (Syk) inhibitor, mitigated the effects of polymicrobial sepsis by reducing tissue inflammation while fully preserving neutrophilic host-defense function.


Assuntos
Nanopartículas , Neutrófilos , Albuminas/metabolismo , Animais , Endocitose , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Camundongos , Neutrófilos/metabolismo
13.
J Virol ; 84(1): 361-71, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19828606

RESUMO

Every year, influenza virus infection causes significant mortality and morbidity in human populations. Although egg-based inactivated viral vaccines are available, their effectiveness depends on the correct prediction of the circulating viral strains and is limited by the time constraint of the manufacturing process. Recombinant subunit vaccines are easier to manufacture with a relatively short lead time but are limited in their efficacy partly because the purified recombinant membrane proteins in the soluble form most likely do not retain their native membrane-bound structure. Nanodisc (ND) particles are soluble, stable, and reproducibly prepared discoid shaped nanoscale structures that contain a discrete lipid bilayer bound by two amphipathic scaffold proteins. Because ND particles permit the functional reconstitution of membrane/envelope proteins, we incorporated recombinant hemagglutinin (HA) from influenza virus strain A/New Caledonia/20/99 (H1N1) into NDs and investigated their potential to elicit an immune response to HA and confer immunity to influenza virus challenge relative to the commercial vaccines Fluzone and FluMist. HA-ND vaccination induced a robust anti-HA antibody response consisting of predominantly the immunoglobulin G1 (IgG1) subclass and a high hemagglutination inhibition titer. Intranasal immunization with HA-ND induced an anti-HA IgA response in nasal passages. HA-ND vaccination conferred protection that was comparable to that of Fluzone and FluMist against challenge with influenza virus strain A/Puerto Rico/8/1934 (H1N1).


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/administração & dosagem , Imunidade Humoral , Vacinas contra Influenza/imunologia , Nanopartículas/uso terapêutico , Infecções por Orthomyxoviridae/prevenção & controle , Animais , Anticorpos Antivirais/biossíntese , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/uso terapêutico , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Proteínas de Membrana/uso terapêutico , Camundongos , Nanopartículas/química , Infecções por Orthomyxoviridae/imunologia , Fosfolipídeos/uso terapêutico
14.
Methods Mol Biol ; 2248: 63-71, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33185867

RESUMO

TNF receptor superfamily comprises many T-cell costimulatory receptors, including TNFRSF1, TNFRSF2, TNFRSF4 (OX40), TNFRSF9 (4-1BB), TNFRSF18 (GITR), and TNFRSF7 (CD27). Signaling through these costimulatory stimulatory receptors can promote conventional T-cell (Tconv) proliferation, and effector functions in an antigen-dependent manner. Thus, agonistic antibodies and ligands for OX40, 4-1BB, GITR, and CD27 have been tested for inducing T-cell-mediated antitumor responses in several cancers. However, recently emerging reports show critical role for TNFR signaling in regulatory T-cell (Treg) differentiation and expansion, which might suppress effector T-cell proliferation and functions. Here, we show preferential over expression of TNFR2, OX40, 4-1BB, and GITR in Treg cells over Tconv cells, and the ability of OX40L and GITRL to induce selective proliferation of Treg cells, but not Tconv cells, in an antigen-independent manner. We describe the standard protocols used for Affymetrix gene expression profiling, T-cell isolation, and Cell Trace Violet-based cell proliferation assay.


Assuntos
Antígenos/imunologia , Ativação Linfocitária/imunologia , Ligante OX40/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Fatores de Necrose Tumoral/metabolismo , Animais , Biomarcadores , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Imunofenotipagem , Ligantes , Ativação Linfocitária/genética , Camundongos , Camundongos Transgênicos , Família Multigênica , Fatores de Necrose Tumoral/genética
15.
J Gen Virol ; 91(Pt 2): 352-61, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19828757

RESUMO

Ebola virus causes rapidly progressive haemorrhagic fever, which is associated with severe immuosuppression. In infected dendritic cells (DCs), Ebola virus replicates efficiently and inhibits DC maturation without inducing cytokine expression, leading to impaired T-cell proliferation. However, the underlying mechanism remains unclear. In this study, we report that Ebola virus VP35 impairs the maturation of mouse DCs. When expressed in mouse immature DCs, Ebola virus VP35 prevents virus-stimulated expression of CD40, CD80, CD86 and major histocompatibility complex class II. Further, it suppresses the induction of cytokines such as interleukin (IL)-6, IL-12, tumour necrosis factor alpha and alpha/beta interferon (IFN-alpha/beta). Notably, Ebola VP35 attenuates the ability of DCs to stimulate the activation of CD4(+) T cells. Addition of type I IFN to mouse DCs only partially reverses the inhibitory effects of VP35. Moreover, VP35 perturbs mouse DC functions induced by lipopolysaccharide, an agonist of Toll-like receptor 4. Deletion of the amino terminus abolishes its activity, whereas a mutation in the RNA binding motif has no effect. Our work highlights a critical role of VP35 in viral interference in DC function with resultant deficiency in T-cell function, which may contribute to the profound virulence of Ebola virus infection.


Assuntos
Células Dendríticas/imunologia , Ebolavirus/imunologia , Doença pelo Vírus Ebola/imunologia , Lipopolissacarídeos/imunologia , Proteínas Virais Reguladoras e Acessórias/imunologia , Animais , Células Cultivadas , Chlorocebus aethiops , Citocinas/genética , Citocinas/imunologia , Células Dendríticas/virologia , Ebolavirus/genética , Doença pelo Vírus Ebola/genética , Doença pelo Vírus Ebola/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Linfócitos T/imunologia , Células Vero , Proteínas Virais Reguladoras e Acessórias/genética
16.
Int Immunol ; 21(3): 269-82, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19174473

RESUMO

GM-CSF plays an essential role in the differentiation of dendritic cells (DCs). Our studies have shown that GM-CSF treatment can induce semi-mature DCs and CD4+CD25+ regulatory T cells (Tregs) and suppress ongoing autoimmunity in mouse models. In this study, we examined the differences in the potential of GM-CSF to exert tolerogenic function on CD8a+ and CD8a- sub-populations of DCs in vivo. We show that GM-CSF modulates CD8a-, but not CD8a+ DCs in vivo, by inhibiting the surface expression of activation markers MHC II and CD80 and production of inflammatory cytokines such as IL-12 and IL-1beta. Self-antigen [mouse thyroglobulin (mTg)] presentation by GM-CSF-exposed CD8a- DCs to T cells from mTg-primed mice induced a profound increase in the frequency of forkhead box P3 (FoxP3)-expressing T cells compared with antigen presentation by GM-CSF-exposed CD8a+ DCs and control CD8a+ and CD8a- DCs. This tolerogenic property of GM-CD8a- DCs was abrogated when IL-12 was added. GM-CSF-exposed CD8a- DCs could also induce secretion of significantly higher amounts of IL-10 by T cells from mTg-primed mice. Importantly, adoptive transfer of CD8a- DCs from GM-CSF-treated SCID mice, but not untreated mice, into wild-type CBA/J mice prevented the development of experimental autoimmune thyroiditis (EAT) in the recipient animals upon immunization with mTg. Collectively, our results show that GM-CSF renders CD8a- DCs tolerogenic, and these DCs induce Foxp3+ and IL-10+ Tregs.


Assuntos
Células Dendríticas/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Interleucina-10/metabolismo , Linfócitos T Reguladores/metabolismo , Tireoidite Autoimune/imunologia , Animais , Apresentação de Antígeno , Antígeno CD11c , Antígenos CD8 , Diferenciação Celular , Proliferação de Células , Células Dendríticas/imunologia , Fatores de Transcrição Forkhead/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Terapia de Imunossupressão , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-12/genética , Interleucina-12/metabolismo , Interleucina-1beta/metabolismo , Camundongos , Camundongos SCID , Tolerância a Antígenos Próprios , Linfócitos T Reguladores/imunologia , Tireoglobulina/imunologia , Tireoidite Autoimune/patologia , Tireoidite Autoimune/prevenção & controle , Vacinação
17.
Bioinformation ; 16(12): 1121-1127, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34938013

RESUMO

It is of interest to assess the association of age and gender of patients undergoing class V tooth colored restoration in maxillary teeth. Records were collected by reviewing the data of 86,000 patients of which 1580 patients had undergone class V tooth colored restoration in maxillary teeth. Patients were divided into age groups 18-30, 31-40,41-50,71-80 years. The most common age group who had undergone class V restoration was in the age group 41-50 years (30.8%). Cervical abrasions were the most common (79%). Most of the patients underwent direct restoration (87.7%). Direct restoration was found to be more prevalent in the age group 41-50 years due to cervical abrasion.

18.
Clin Adv Periodontics ; 10(4): 181-185, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32749743

RESUMO

INTRODUCTION: The management of gingival recession associated with esthetic concerns and root hypersensitivity is challenging, and its sequelae is based on the assessment of etiological factors and the degree of tissue involvement. Procedures using pedicle flaps, free soft tissue grafts, combination of pedicle flaps with grafts, barrier membranes, and the use of platelet concentrates are all effective for this purpose. The use of the third-generation platelet concentrate, advanced platelet-rich fibrin (A-PRF), has evolved as a promising regenerative material for root coverage procedure wherein it acts as a scaffold and also accelerates wound healing due to its dense fibrin meshwork. CASE PRESENTATION: This case report, discusses treating an isolated maxillary Miller Class I recession in a 25-year-old male patient by a periosteal inversion method along with the A-PRF membrane. A partial thickness flap was reflected; periosteum was inverted; and an A-PRF membrane was placed over the denuded root surface which aided in enhanced regeneration; 100% root coverage was obtained as seen in follow-up visits. CONCLUSION: The periosteal inversion technique along with an A-PRF membrane seems to be a novel approach in managing an isolated Miller Class I maxillary gingival recession.


Assuntos
Retração Gengival , Fibrina Rica em Plaquetas , Adulto , Estética Dentária , Fibrina , Retração Gengival/cirurgia , Humanos , Masculino , Resultado do Tratamento
19.
Clin Immunol ; 131(2): 260-70, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19171501

RESUMO

Abnormalities in DC function are implicated in defective immune regulation that leads to type-1 diabetes (T1D) in NOD mice and humans. In this study, we used GM-CSF and Flt3-L to modulate DC function in NOD mice and observed the effects on T1D development. Treatment with either ligand at earlier stages of insulitis suppressed the development of T1D. Unlike Flt3-L, GM-CSF was more effective in suppressing T1D, even when administered at later stages of insulitis. In vitro studies and in vivo adoptive transfer experiments revealed that CD4+CD25+ T cells from GM-CSF-treated mice could suppress effector T cell response and T1D. This suppression is likely mediated through enhanced IL-10 and TGF-beta1 production. Adoptive transfer of GM-CSF exposed DCs to naive mice resulted in an expansion of Foxp3+ T cells and a significant delay in T1D onset. Our results indicate that GM-CSF acted primarily on DCs and caused an expansion of Foxp3+ Tregs which delayed the onset of T1D in NOD mice.


Assuntos
Células Dendríticas/efeitos dos fármacos , Diabetes Mellitus Tipo 1/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Fatores Imunológicos/farmacologia , Linfócitos T Reguladores/efeitos dos fármacos , Idade de Início , Animais , Células Dendríticas/citologia , Células Dendríticas/imunologia , Diabetes Mellitus Tipo 1/fisiopatologia , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Interleucina-10/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Linfócitos T Reguladores/imunologia , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima/efeitos dos fármacos
20.
Clin Adv Periodontics ; 9(3): 135-141, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31490039

RESUMO

INTRODUCTION: Treating the patients with excessive gingival display to provide a pleasant smile is a challenge to the periodontist. Gummy smile can be due to excessive vertical bone growth, dentoalveolar extrusion, short upper lip, upper lip hyperactivity, or altered passive eruption. Gummy smile associated with hyperactivity of smile elevator muscles can be treated by surgical techniques like lip repositioning, botulinum toxin injection, lip elongation with rhinoplasty, detachment of the lip muscles, and myectomy. Regardless of the technique used, to achieve a predictable result with long-term stability limiting upper lip movement when the patient smiles, firm muscle containment is imperative. CASE PRESENTATION: The case report describes the excessive gingival display having a multifactorial etiology in a 25-year-old female patient. Altered passive eruption in upper anterior teeth was treated by crown lengthening followed by management of hyperactive lip using a diode laser-assisted lip repositioning along with traction and muscle containment. Excellent and predictable results were obtained after a 1-year follow-up without the relapse of gummy smile. CONCLUSIONS: The case report showed an excellent result when treated by a combined approach of an innovative procedure with laser-assisted lip repositioning aimed at maintaining the traction and containment of the smile elevator muscles along with crown lengthening procedure by gingivectomy.


Assuntos
Aumento da Coroa Clínica , Estética Dentária , Gengivectomia , Lábio , Adulto , Feminino , Humanos , Lábio/anatomia & histologia , Lábio/cirurgia , Sorriso
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA