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1.
Cancer Immunol Res ; 8(6): 829-841, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32238382

RESUMO

Langerhans cell histiocytosis (LCH) is a rare disorder characterized by tissue accumulation of CD1a+CD207+ LCH cells. In LCH, somatic mutations of the BRAF V600E gene have been detected in tissue LCH cells, bone marrow CD34+ hematopoietic stem cells, circulating CD14+ monocytes, and BDCA1+ myeloid dendritic cells (DC). Targeting BRAF V600E in clonal Langerhans cells (LC) and their precursors is a potential treatment option for patients whose tumors have the mutation. The development of mouse macrophages and LCs is regulated by the CSF1 receptor (CSF1R). In patients with diffuse-type tenosynovial giant cell tumors, CSF1R inhibition depletes tumor-associated macrophages (TAM) with therapeutic efficacy; however, CSF1R signaling in LCs and LCH has not been investigated. We found through IHC and flow cytometry that CSF1R is normally expressed on human CD1a+CD207+ LCs in the epidermis and stratified epithelia. LCs that were differentiated from CD14+ monocytes, BDCA1+ DCs, and CD34+ cord blood progenitors expressed CSF1R that was downregulated upon maturation. Immature LCs migrated toward CSF1, but not IL34. Administration of the c-FMS/CSF1R kinase inhibitors GW2580 and BLZ945 significantly reduced human LC migration. In LCH clinical samples, LCH cells (including BRAF V600E cells) and TAMs retained high expression of CSF1R. We also detected the presence of transcripts for its ligand, CSF1, but not IL34, in all tested LCH cases. CSF1R and CSF1 expression in LCH, and their role in LC migration and differentiation, suggests CSF1R signaling blockade as a candidate rational approach for treatment of LCH, including the BRAF V600E and wild-type forms of the disease.

2.
Minerva Anestesiol ; 86(6): 617-626, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31994367

RESUMO

BACKGROUND: Normothermic ex-vivo lung perfusion (EVLP) limits organ donor shortage by potentially using high-risk donor lungs. Microbial burden reduction has been demonstrated after EVLP using antibiotic prophylaxis with imipenem. However, no data have been published on the clinical consequences of the potential residual bacterial burden. METHODS: Imipenem concentration was measured every hour (T0 to T6) in the lung perfusate and at the end of EVLP (Tf) in biopsies. The antimicrobial activity of perfusate at T1 and Tf against E. coli and K. pneumoniae was evaluated. Lungs were distinguished: no bacterial species in recipients and donors (donor-/recipient-); bacterial species isolated from donors and not from recipients (donor+/recipient-); same bacterial species in both recipients and donors (donor+/recipient+). Interleukin 6 (IL-6) and IL-8 concentrations in lung perfusate, clinical pulmonary infection score (CPIS) and primary graft dysfunction (PGD) were evaluated. RESULTS: Imipenem concentration in perfusate decreased over time. T1 and Tf perfusates exhibited bactericidal activity against E. coli and K. pneumoniae. Overall, T1 perfusates yielded higher bactericidal titers (BTs) than Tf. The donor+/recipient+ group (26% of cases) had higher IL-6 and IL-8 in perfusate and higher CPIS. CONCLUSIONS: Recipients with the same bacterial species isolated in their donors had higher risk of pulmonary inflammation and early post-transplant pneumonia. Improvements in antimicrobial strategies during EVLP are warranted to minimize the consequences of donor associated respiratory infection.

3.
Sci Rep ; 9(1): 10622, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31337804

RESUMO

Systemic inflammation and uremic toxins (UT) determine the increased cardiovascular mortality observed in chronic hemodialysis (HD) patients. Among UT, the adipokine Chemerin induces vascular dysfunction by targeting both endothelial and vascular smooth muscular cells (EC and VSMC). As Citrate anion modulates oxidative metabolism, systemic inflammation and vascular function, we evaluated whether citrate-buffered dialysis improves HD efficiency, inflammatory parameters and chemerin-mediated microvascular injury. 45 patients were treated in sequence with acetate, citrate and, again, acetate-buffered dialysis solution (3 months per interval). At study admission and after each treatment switch, we evaluated dialysis efficacy and circulating levels of chemerin and different inflammatory biomarkers. In vitro, we stimulated EC and VSMC with patients' plasma and we investigated the role of chemerin as UT. Citrate dialysis increased HD efficacy and reduced plasma levels of CRP, fibrinogen, IL6 and chemerin. In vitro, patients' plasma induced EC and VSMC dysfunction. These effects were reduced by citrate-buffered solutions and paralleled by the decrease of chemerin levels. Consistently, chemerin receptor knockdown reduced EC and VSMC dysfunction. In conclusion, Switching from acetate to citrate improved dialysis efficacy and inflammatory parameters; in vitro, chemerin-induced EC and VSMC injury were decreased by using citrate as dialysis buffer.

4.
Cytokine Growth Factor Rev ; 50: 19-28, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31126876

RESUMO

Osteopontin (OPN) is a pleiotropic cytokine produced both by immune and non-immune cells and active on different cellular targets. OPN production has been associated with several pathological conditions, including autoimmune diseases (e.g. lupus, multiple sclerosis and rheumatoid arthritis) and cancer. Emerging evidence suggests that the role of OPN has been underestimated, as it seems to be working at multiple levels of immune regulation, such as the shaping of T cell effector responses, the regulation of the tumor microenvironment, and the functional interaction with mesenchymal stromal cells. In this context, dendritic cells (DCs) play a crucial role being both an important source and a cellular target for OPN action. DC family is composed by several cell subsets endowed with specific immune functions. OPN exerts its biological functions through multiple receptors and is produced in different intracellular and secreted forms. OPN production by DC subsets is emerging as a crucial mechanism of regulation in normal and pathological conditions and starts to be exploited as a therapeutic target. This review will focus on the role of DC-derived OPN in shaping immune response and on the complex role of this cytokines in the regulation in immune response.

5.
Chimia (Aarau) ; 73(4): 294-298, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30975259

RESUMO

Atomistic simulations are a powerful tool to explain and guide experimental investigations, but there are cases where a clear correspondence is difficult to obtain. While the theoretical framework to get the static picture of the equilibrium structures in vacuum is well-established, it is challenging to correctly model them in operando conditions (at the right experimental temperature, pH and pressure). In this short review the main theoretical approaches are briefly presented, supported by selected case studies where the structural and dynamical properties of different systems are investigated. A successful match with the experimental data is accomplished by choosing the proper level of theory in order to describe the structure under study in the most accurate and realistic way.

6.
Pharmaceutics ; 11(3)2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30897794

RESUMO

Imiquimod (IMQ) is an immune response modifier clinically used for the treatment of various topical diseases. However, its poor aqueous solubility and skin penetration capability make the topical delivery of IMQ a challenging task. This work aims at developing a nanomedicine-based topical formulation, carrying IMQ to control the scarring process for the treatment of aberrant wounds. For this purpose, IMQ was loaded in ß-cyclodextrin-based nanosponges and dispersed in a hydrogel suitable for dermal application. The formulation was characterized in vitro and compared with IMQ inclusion complexes, with (2-hydroxy)propyl ß-cyclodextrin(HPßCD) and carboxymethyl ß-cyclodextrin (CMßCD) showing enhanced penetration properties. The hydrogel containing IMQ-loaded nanosponges could act as a drug reservoir and guarantee the sustained release of IMQ through the skin. A greater inhibitory effect on fibroblast proliferation was observed for IMQ loaded in nanosponges compared to the other formulations.

7.
PLoS One ; 14(2): e0211945, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30735549

RESUMO

Cat scratch disease (CSD) is an infectious disease caused by Bartonella henselae, usually characterized by self-limiting regional lymphadenopathy and fever. Given the low clinical diagnostic sensitivity and specificity of conventional anti-B. henselae indirect immunofluorescence assays (IFAs), real-time polymerase chain reaction (PCR)-based detection of B. henselae is now being proposed as a more sensitive tool to diagnose CSD. Thus, here we have assessed the efficacy of real-time PCR in detecting B. henselae in different specimens from patients with suspected CSD and compared it to that of IFA. From March 2011 to May 2016, at the Microbiology and Virology Unit, Azienda Ospedaliera Universitaria Città della Salute e della Scienza di Torino, Turin, Italy, 115 clinical specimens (56 aspirated pus, 39 fresh lymph node biopsies, and 20 whole blood samples) and 99 sera from 115 patients with suspected CSD (62 females and 53 males between the ages of 3 months and 68 years) were analyzed by both real-time PCR, used in a qualitative way, and IFA (IgM and IgG) for the presence of B. henselae. For 16 patients, serological results were not available due to a clinical decision not to request the test. B. henselae DNA positivity was detected by real-time PCR in 37.39% of patients, while 62.61% of them were negative. Thus, patients were divided into two groups: real-time PCR+ (n = 43) and real-time PCR- (n = 72). Real-time PCR screening of whole blood, biopsies, and aspirated pus revealed B. henselae positivity in 40%, 38.46%, and 35.71% of patients, respectively. When we analyzed samples by IFA, we found the presence of B. henselae in 28 out of 99 (28.28%) patients, of which 11 (11.11%) belonged to the real-time PCR+ group and 17 (17.17%) to the real-time PCR- group. Among the 71 seronegative subjects, 16 (16.16%) were found positive for B. henselae by real-time PCR. Thus, by combining the results of both assays, we were able to increase the percentage of B. henselae positive specimens from 27.27% (real-time PCR) or 28.28% (IFA) to 44.44% (real-time PCR+IFA). Altogether, these findings indicate that the early detection of B. henselae in patients with suspicious CSD through combined real-time PCR and serological analyses can lead to a more accurate diagnosis of CSD, thereby allowing prompt and appropriate disease management.


Assuntos
Anticorpos Antibacterianos/metabolismo , Bartonella henselae/isolamento & purificação , Doença da Arranhadura de Gato/diagnóstico , DNA Bacteriano/genética , Adolescente , Adulto , Idoso , Bartonella henselae/genética , Bartonella henselae/imunologia , Doença da Arranhadura de Gato/imunologia , Criança , Pré-Escolar , Diagnóstico Precoce , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Lactente , Itália , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Adulto Jovem
8.
Viruses ; 10(10)2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30332797

RESUMO

Interleukin-1ß (IL-1ß) is a key effector of the inflammasome complex in response to pathogens and danger signals. Although it is well known that assembly of the inflammasome triggers proteolytic cleavage of the biologically inactive precursor pro-IL-1ß into its mature secreted form, the mechanism by which human cytomegalovirus (HCMV) regulates IL-1ß production via the inflammasome is still poorly understood. Here, we show that the infection of human foreskin fibroblasts (HFFs) with a mutant HCMV lacking the tegument protein pp65 (v65Stop) results in higher expression levels of mature IL-1ß compared to its wild-type counterpart, suggesting that pp65 mediates HCMV immune evasion through downmodulation of IL-1ß. Furthermore, we show that enhanced IL-1ß production by the v65Stop mutant is due in part to induction of DNA binding and the transcriptional activity of NF-κB. Lastly, we demonstrate that HCMV infection of HFFs triggers a non-canonical IL-1ß activation pathway where caspase-8 promotes IL-1ß maturation independently of caspase-1. Altogether, our findings provide novel mechanistic insights into the interplay between HCMV and the inflammasome system and raise the possibility of targeting pp65 to treat HCMV infection.


Assuntos
Infecções por Citomegalovirus/genética , Citomegalovirus/imunologia , Interleucina-1beta/genética , NF-kappa B/genética , Fosfoproteínas/imunologia , Proteínas da Matriz Viral/imunologia , Linhagem Celular , Citomegalovirus/genética , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/fisiopatologia , Infecções por Citomegalovirus/virologia , Fibroblastos/imunologia , Fibroblastos/virologia , Interações Hospedeiro-Patógeno , Humanos , Evasão da Resposta Imune , Interleucina-1beta/imunologia , NF-kappa B/metabolismo , Fosfoproteínas/genética , Regulação para Cima , Proteínas da Matriz Viral/genética
9.
Front Immunol ; 9: 1207, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29910810

RESUMO

Mesenchymal stromal cells (MSCs) exert immunosuppressive effects on immune cells including dendritic cells (DCs). However, many details of the bidirectional interaction of MSCs with DCs are still unsolved and information on key molecules by which DCs can modulate MSC functions is limited. Here, we report that osteopontin (OPN), a cytokine involved in homeostatic and pathophysiologic responses, is constitutively expressed by DCs and regulated in the DC/MSC cocultures depending on the activation state of MSCs. Resting MSCs promoted OPN production, whereas the production of OPN was suppressed when MSCs were activated by proinflammatory cytokines (i.e., TNF-α, IL-6, and IL-1ß). OPN induction required cell-to-cell contact, mediated at least in part, by ß1 integrin (CD29). Conversely, activated MSCs inhibited the release of OPN via the production of soluble factors with a major role played by Prostaglandin E2 (PGE2). Accordingly, pretreatment with indomethacin significantly abrogated the MSC-mediated suppression of OPN while the direct addition of exogenous PGE2 inhibited OPN production by DCs. Furthermore, DC-conditioned medium promoted osteogenic differentiation of MSCs with a concomitant inhibition of adipogenesis. These effects were paralleled by the repression of the adipogenic markers PPARγ, adiponectin, and FABP4, and induction of the osteogenic markers alkaline phosphatase, RUNX2, and of the bone-anabolic chemokine CCL5. Notably, blocking OPN activity with RGD peptides or with an antibody against CD29, one of the OPN receptors, prevented the effects of DC-conditioned medium on MSC differentiation and CCL5 induction. Because MSCs have a key role in maintenance of bone marrow (BM) hematopoietic stem cell niche through reciprocal regulation with immune cells, we investigated the possible MSC/DC interaction in human BM by immunohistochemistry. Although DCs (CD1c+) are a small percentage of BM cells, we demonstrated colocalization of CD271+ MSCs with CD1c+ DCs in normal and myelodysplastic BM. OPN reactivity was observed in occasional CD1c+ cells in the proximity of CD271+ MSCs. Altogether, these results candidate OPN as a signal modulated by MSCs according to their activation status and involved in DC regulation of MSC differentiation.


Assuntos
Adaptação Biológica , Comunicação Celular , Células Dendríticas/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Osteopontina/biossíntese , Antígenos CD1/metabolismo , Medula Óssea/metabolismo , Diferenciação Celular , Quimiocina CCL5/biossíntese , Técnicas de Cocultura , Células Dendríticas/imunologia , Glicoproteínas/metabolismo , Humanos , Imuno-Histoquímica , Células-Tronco Mesenquimais/citologia
10.
Cardiovasc Diabetol ; 16(1): 71, 2017 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-28569217

RESUMO

Mechanisms underlying the pathogenesis of ischemia/reperfusion injury are particularly complex, multifactorial and highly interconnected. A complex and entangled interaction is also emerging between platelet function, antiplatelet drugs, coronary diseases and ischemia/reperfusion injury, especially in diabetic conditions. Here we briefly summarize features of antiplatelet therapy in type 2 diabetes (T2DM). We also treat the influence of T2DM on ischemia/reperfusion injury and how anti-platelet therapies affect post-ischemic myocardial damage through pleiotropic properties not related to their anti-aggregating effects. miRNA-based signature associated with T2DM and its cardiovascular disease complications are also briefly considered. Influence of anti-platelet therapies and different effects of healthy and diabetic platelets on ischemia/reperfusion injury need to be further clarified in order to enhance patient benefits from antiplatelet therapy and revascularization. Here we provide insight on the difficulty to reduce the cardiovascular risk in diabetic patients and report novel information on the cardioprotective role of widely used anti-aggregant drugs.


Assuntos
Aspirina/uso terapêutico , Plaquetas/efeitos dos fármacos , Diabetes Mellitus Tipo 2/complicações , Precondicionamento Isquêmico Miocárdico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , Inibidores da Agregação de Plaquetas/uso terapêutico , Animais , Aspirina/efeitos adversos , Plaquetas/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/genética , Resistência a Medicamentos , Humanos , Precondicionamento Isquêmico Miocárdico/efeitos adversos , MicroRNAs/genética , MicroRNAs/metabolismo , Traumatismo por Reperfusão Miocárdica/sangue , Traumatismo por Reperfusão Miocárdica/etiologia , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Inibidores da Agregação de Plaquetas/efeitos adversos , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento
11.
J Mol Med (Berl) ; 94(8): 943-55, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26960761

RESUMO

UNLABELLED: Langerhans cells (LCs) are a specialized dendritic cell subset that resides in the epidermis and mucosal epithelia and is critical for the orchestration of skin immunity. Recent evidence suggest that LCs are involved in aberrant wound healing and in the development of hypertrophic scars and chronic wounds, which are characterized by a hypoxic environment. Understanding LCs biology under hypoxia may, thus, lead to the identification of novel pathogenetic mechanisms of wound repair disorders and open new therapeutic opportunities to improve wound healing. In this study, we characterize a previously unrecognized role for hypoxia in significantly affecting the phenotype and functional properties of human monocyte-derived LCs, impairing their ability to stimulate naive T cell responses, and identify the triggering receptor expressed on myeloid (TREM)-1, a member of the Ig immunoregulatory receptor family, as a new hypoxia-inducible gene in LCs and an activator of their proinflammatory and Th1-polarizing functions in a hypoxic environment. Furthermore, we provide the first evidence of TREM-1 expression in vivo in LCs infiltrating hypoxic areas of active hypertrophic scars and decubitous ulcers, pointing to a potential pathogenic role of this molecule in wound repair disorders. KEY MESSAGES: Hypoxia modulates surface molecule expression and cytokine profile in Langerhans cells. Hypoxia impairs human Langerhans cell stimulatory activity on naive T cells. Hypoxia selectively induces TREM-1 expression in human Langerhans cells. TREM-1 engagement stimulates Langerhans cell inflammatory and Th1-polarizing activity. TREM-1 is expressed in vivo in Langerhans cells infiltrating hypoxic skin lesions.


Assuntos
Células de Langerhans/fisiologia , Hipóxia Celular , Proliferação de Células , Células Cultivadas , Cicatriz Hipertrófica/imunologia , Cicatriz Hipertrófica/metabolismo , Cicatriz Hipertrófica/patologia , Citocinas/metabolismo , Humanos , Ativação Linfocitária , Pele/imunologia , Pele/patologia , Linfócitos T/fisiologia , Receptor Gatilho 1 Expresso em Células Mieloides/metabolismo
12.
Cytokine Growth Factor Rev ; 26(6): 647-57, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26115564

RESUMO

The TGF-ß superfamily consists of a large group of pleiotropic cytokines that are involved in the regulation of many developmental, physiological and pathological processes. Dendritic cells are antigen-presenting cells that play a key role in innate and adaptive immune responses. Dendritic cells have a complex relationship with the TGF-ß cytokine superfamily being both source and targets for many of these cytokines. Some TGF-ß family members are expressed by dendritic cells and modulate immune responses, for instance through the induction of T cell polarization. Others play a crucial role in the development and function of the different dendritic cell subsets. This review summarizes the current knowledge on the role of TGF-ß family cytokines in dendritic cell biology, focusing on TGF-ß as well as on other, less characterized, members of these important immune mediators.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/fisiologia , Fator de Crescimento Transformador beta/imunologia , Fator de Crescimento Transformador beta/metabolismo , Ativinas/imunologia , Ativinas/metabolismo , Proteínas Morfogenéticas Ósseas/imunologia , Regulação da Expressão Gênica , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/fisiologia , Ligantes , Transdução de Sinais , Linfócitos T/imunologia , Linfócitos T/fisiologia , Fator de Crescimento Transformador beta/biossíntese
13.
PLoS One ; 10(6): e0131557, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26121651

RESUMO

Multiple Sclerosis patients run an increased risk of microbial infections, which leads to high rates of hospitalization and infection-related mortality. Although immunotherapy may increase infection risk in some cases, data as to the relationship among microbial factors, immunotherapy and alterations in the innate immunity of these patients are still scanty. On these grounds, this interdisciplinary study aims at investigating the role the functional activity of polymorphonuclear cells (PMNs) play in relapsing remitting multiple sclerosis at different stages. The in vitro ability of PMNs from patients, either untreated or treated with immunosuppressant or immunomodulatory drugs to kill Klebsiella pneumonia or Candida albicans, were investigated and compared to PMNs from healthy subjects. The release of various cytokines was also assessed, as was the production of reactive oxygen species and their ability to regulate apoptosis after microbial stimulation. Our results indicate that although patients have a normal number of PMNs, they have a statistically significant (p<0.05) reduction in intracellular killing activity. Although variations are strongly related to the therapeutic management of patients, they are independent from their disease stage. As no statistically significant differences were observed between patients and controls in cytokine release values, reactive oxygen species production or apoptosis, we came to the conclusion that other factors may be involved. Supportive validation of these results from further studies might well help in identifying a subset of patients at high risk of infection who could benefit from a closer follow-up and/or antibiotic prophylaxis.


Assuntos
Leucócitos Mononucleares/patologia , Esclerose Múltipla Recidivante-Remitente/patologia , Adulto , Apoptose/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Morte Celular/efeitos dos fármacos , Citocinas/metabolismo , Demografia , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Espaço Intracelular/metabolismo , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/fisiologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/microbiologia , Masculino , Pessoa de Meia-Idade , Natalizumab/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Explosão Respiratória/efeitos dos fármacos , Adulto Jovem
14.
J Exp Med ; 212(6): 905-25, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25964372

RESUMO

Pentraxin 3 (PTX3) is a fluid-phase pattern recognition molecule and a key component of the humoral arm of innate immunity. In four different models of tissue damage in mice, PTX3 deficiency was associated with increased fibrin deposition and persistence, and thicker clots, followed by increased collagen deposition, when compared with controls. Ptx3-deficient macrophages showed defective pericellular fibrinolysis in vitro. PTX3-bound fibrinogen/fibrin and plasminogen at acidic pH and increased plasmin-mediated fibrinolysis. The second exon-encoded N-terminal domain of PTX3 recapitulated the activity of the intact molecule. Thus, a prototypic component of humoral innate immunity, PTX3, plays a nonredundant role in the orchestration of tissue repair and remodeling. Tissue acidification resulting from metabolic adaptation during tissue repair sets PTX3 in a tissue remodeling and repair mode, suggesting that matrix and microbial recognition are common, ancestral features of the humoral arm of innate immunity.


Assuntos
Proteína C-Reativa/metabolismo , Imunidade Humoral/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Animais , Artérias/patologia , Coagulação Sanguínea , Sistema Livre de Células , Colágeno/metabolismo , Feminino , Fibrina/metabolismo , Fibrinólise , Regulação da Expressão Gênica , Concentração de Íons de Hidrogênio , Imunidade Inata , Leucócitos/citologia , Fígado/lesões , Lesão Pulmonar/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Fenótipo , Plasminogênio/metabolismo , Estrutura Terciária de Proteína , Pele/imunologia , Pele/patologia , Ressonância de Plasmônio de Superfície , Trombose/patologia , Cicatrização
15.
J Interferon Cytokine Res ; 35(3): 232-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25333950

RESUMO

Adaptor protein-3 (AP-3) is a heterotetrameric complex, which regulates vesicular trafficking. Mutations of the ß3A subunit cause the Hermansky-Pudlak syndrome type 2 (HPS-2), a rare genetic disease characterized by albinism, platelet defects, and recurrent infections. Likewise, pearl mice, which lack functional AP-3, show several HPS-2 defects. The AP-3 absence results in defective toll-like receptor trafficking and signaling in dendritic cells (DC), but its effect on the efficiency of the in vivo antiviral response is unclear. We evaluated the impact of AP-3 deficiency on the distribution of DC subsets, interferon (IFN) production, and the susceptibility to murine cytomegalovirus (MCMV) infection. Pearl mice showed a distribution and frequency of conventional (cDC) and plasmacytoid DC (pDC) similar to that of wild-type mice both before and after MCMV infection. Moreover, pearl mice controlled MCMV infection even at high virus doses and showed a normal production of IFN-α. Since pDC, but not cDC, from pearl mice showed an impaired IFN-α and tumor necrosis factor-α production in response to prototypic DNA (MCMV and Herpes Simplex virus) or RNA (Vesicular Stomatitis virus) viruses in vitro, it is likely that MCMV infection can be controlled in vivo independently of an efficient production of IFN-α by pDC, and that the AP-3 complex has a minimal impact on protective antiviral responses.


Assuntos
Complexo 3 de Proteínas Adaptadoras/genética , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Células Dendríticas/imunologia , Síndrome de Hermanski-Pudlak/genética , Interferon-alfa/metabolismo , Animais , Células Cultivadas , Células Dendríticas/virologia , Humanos , Imunidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Fator de Necrose Tumoral alfa/metabolismo
16.
Oncotarget ; 6(4): 2206-21, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25544768

RESUMO

SERPINB3 is a cysteine-proteases inhibitor up-regulated in a significant number of cirrhotic patients carrying hepatocellular carcinoma (HCC) and recently proposed as a prognostic marker for HCC early recurrence. SERPINB3 has been reported to stimulate proliferation, inhibit apoptosis and, similar to what reported for hypoxia, to trigger epithelial-to-mesenchymal transition (EMT) and increased invasiveness in liver cancer cells. This study has investigated whether SERPINB3 expression is regulated by hypoxia-related mechanisms in liver cancer cells. Exposure of HepG2 and Huh7 cells to hypoxia up-regulated SERPINB3 transcription, protein synthesis and release in the extracellular medium. Hypoxia-dependent SERPINB3 up-regulation was selective (no change detected for SERPINB4) and operated through hypoxia inducible factor (HIF)-2α (not HIF-1α) binding to SERPINB3 promoter, as confirmed by chromatin immuno-precipitation assay and silencing experiments employing specific siRNAs. HIF-2α-mediated SERPINB3 up-regulation under hypoxic conditions required intracellular generation of ROS. Immuno-histochemistry (IHC) and transcript analysis, performed in human HCC specimens, revealed co-localization of the two proteins in liver cancer cells and the existence of a positive correlation between HIF-2α and SERPINB3 transcript levels, respectively. Hypoxia, through HIF-2α-dependent and redox-sensitive mechanisms, up-regulates the transcription, synthesis and release of SERPINB3, a molecule with a high oncogenic potential.


Assuntos
Antígenos de Neoplasias/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Serpinas/genética , Regulação para Cima , Antígenos de Neoplasias/metabolismo , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Western Blotting , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Hipóxia Celular , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Células HT29 , Células Hep G2 , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Ligação Proteica , Interferência de RNA , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serpinas/metabolismo
17.
ACS Nano ; 8(11): 11432-9, 2014 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-25347209

RESUMO

The excellent physical and semiconducting properties of transition metal dichalcogenide (TMDC) monolayers make them promising materials for many applications. The TMDC monolayer MoS2 has gained significant attention as a channel material for next-generation transistors. However, while n-type single-layer MoS2 devices can be made with relative ease, fabrication of p-type transistors remains a challenge as the Fermi-level of elemental metals used as contacts are pinned close to the conduction band leading to large p-type Schottky barrier heights (SBH). Here, we propose the utilization of graphene oxide (GO) as an efficient hole injection layer for single-layer MoS2-based electronic and optoelectronic devices. Using first-principles computations, we demonstrate that GO forms a p-type contact with monolayer MoS2, and that the p-type SBH can be made smaller by increasing the oxygen concentration and the fraction of epoxy functional groups in GO. Our analysis shows that this is possible due to the high work function of GO and the relatively weak Fermi-level pinning at the MoS2/GO interfaces compared to traditional MoS2/metal systems (common metals are Ag, Al, Au, Ir, Pd, Pt). The combination of easy-to-fabricate and inexpensive GO with MoS2 could be promising for the development of hybrid all-2D p-type electronic and optoelectronic devices on flexible substrates.

18.
Phys Rev Lett ; 113(10): 106103, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25238371

RESUMO

We study a crystalline epitaxial alumina thin film with the characteristics of a spinel-type transition Al2O3(100) surface by using atom-resolved noncontact atomic force microscopy and density functional theory. It is shown that the films are terminated by an Al-O layer rich in Al vacancies, exhibiting a strong preference for surface hydroxyl group formation in two configurations. The transition alumina films are crystalline and perfectly stable in ambient atmospheres, a quality which is expected to open the door to new fundamental studies of the surfaces of transition aluminas.

19.
J Leukoc Biol ; 94(1): 147-58, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23610145

RESUMO

OPN, a cytokine produced, among others, by DCs, is involved in inflammation and defense against pathogens. Here, we report that the activation of the MyD88 pathway by TLR2, TLR5, and TLR7/8 agonists or IL-1ß induces high levels of OPN in human DCs. Conversely, LPS and Poly I:C, two TLR3 and TLR4 agonists that engage the TRIF pathway, were ineffective. TLR2 agonists were the strongest OPN inducers, and OPN production was highly stimulated by TLR2-triggering bacteria (Staphylococcus aureus) but not by TLR4-triggering Escherichia coli. Costimulation experiments revealed that TLR3 and TLR4 agonists, beyond being inactive by themselves, sharply limited TLR2-dependent OPN production by activating a TRIF-dependent inhibition of the MyD88-dependent OPN production. MyD88 silencing impaired TLR2-dependent OPN induction, whereas TRIF pathway blockage by chloroquine, dynasore, or TRIF knockdown prevented the TLR3/4 agonist-mediated inhibition, which was independent from the endogenous production of type I IFN, IL-29, IL-10, or TGF-ß. LPS and Poly I:C inhibitory activity was associated with the release of a >10-kDa protein factor(s). We also demonstrated that the higher OPN levels produced by S. aureus-treated DCs compared with E. coli-treated DCs were responsible for a markedly increased production of IL-17 by CD4⁺ T cells. These results highlight the biological relevance of the differential OPN induction by TLR2 and TLR4 agonists and emphasize the importance of TLR cross-talk in OPN induction. This implies that OPN regulation by TLR signaling is critical in shaping inflammatory responses and may modulate IL-17 production in response to pathogens.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Escherichia coli/imunologia , Osteopontina/metabolismo , Staphylococcus aureus/imunologia , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/antagonistas & inibidores , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Western Blotting , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Citocinas/genética , Citocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Escherichia coli/metabolismo , Regulação da Expressão Gênica , Humanos , Interleucina-17/genética , Interleucina-17/metabolismo , Lipopolissacarídeos/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Monócitos/metabolismo , Fator 88 de Diferenciação Mieloide/antagonistas & inibidores , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Staphylococcus aureus/metabolismo , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
20.
Eur J Immunol ; 43(4): 949-66, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23436478

RESUMO

DCs are powerful antigen-presenting cells central in the orchestration of innate and acquired immunity. DC development, migration, and activities are intrinsically linked to the microenvironment. DCs migrate through pathologic tissues before reaching their final destination in the lymph nodes. Hypoxia, a condition of low partial oxygen pressure, is a common feature of many pathologic situations, capable of modifying DC phenotype and functional behavior. We studied human monocyte-derived immature DCs generated under chronic hypoxic conditions (H-iDCs). We demonstrate by gene expression profiling the upregulation of a cluster of genes coding for antigen-presentation, immunoregulatory, and pattern recognition receptors, suggesting a stimulatory role for hypoxia on iDC immunoregulatory functions. In particular, we show that H-iDCs express triggering receptor expressed on myeloid cells(TREM-1), a member of the Ig superfamily of immunoreceptors and an amplifier of inflammation. This effect is reversible because H-iDC reoxygenation results in TREM-1 down-modulation. TREM-1 engagement promotes upregulation of T-cell costimulatory molecules and homing chemokine receptors, typical of mature DCs, and increases the production of proinflammatory, Th1/Th17-priming cytokines/chemokines, resulting in increased T-cell responses. These results suggest that TREM-1 induction by the hypoxic microenvironment represents a mechanism of regulation of Th1-cell trafficking and activation by iDCs differentiated at pathologic sites.


Assuntos
Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Mediadores da Inflamação/metabolismo , Glicoproteínas de Membrana/metabolismo , Fenótipo , Receptores Imunológicos/metabolismo , Hipóxia Celular , Células Cultivadas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Glicoproteínas de Membrana/genética , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Células Th1/imunologia , Células Th1/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Receptor Gatilho 1 Expresso em Células Mieloides
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