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1.
Breast Cancer Res Treat ; 200(2): 203-215, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37219637

RESUMO

PURPOSE: This study aimed to compare the prognosis in terms of disease-free survival (DFS) in three populations of women with breast cancer (BC) treated with neoadjuvant systemic treatment (NAST) in which axillary lymph node dissection (ALND) was performed based on different total tumor load (TTL) thresholds in the sentinel nodes. METHODS: This was an observational, retrospective study carried out in three Spanish centers. Data from patients with infiltrating BC who underwent BC surgery after NAST and intraoperative sentinel lymph node biopsy (SLNB) performed by One Step Nucleic acid Amplification (OSNA) technique during 2017 and 2018 were analyzed. ALND was performed according to the protocol of each center, based on three different TTL cut-offs (TTL > 250, TTL > 5000, and TTL > 15,000 CK19-mRNA copies/µL for centers 1, 2, and 3, respectively). RESULTS: A total of 157 BC patients were included in the study. No significant differences in DFS were observed between centers (Hazard ratio [HR] center 2 vs 1: 0.77; p = 0.707; HR center 3 vs 1: 0.83; p = 0.799). Patients with ALND had a shorter DFS (HR 2.43; p = 0.136), albeit not statistically significant. Patients with a triple negative subtype had a worse prognosis than those with other molecular subtypes (HR 2.82; p = 0.056). CONCLUSION: No significant differences in DFS were observed between three centers with different surgical approaches to ALND based on different TTL cut-offs in patients with BC after NAST. These results suggest that restricting ALND to those patients with TTL ≥ 15,000 copies/µL is a reliable approximation, avoiding unnecessary morbidities caused by ALND.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/cirurgia , Terapia Neoadjuvante , Estudos Retrospectivos , Carga Tumoral , Biópsia de Linfonodo Sentinela/métodos , Excisão de Linfonodo/métodos , Prognóstico , Axila/patologia , Linfonodos/patologia
2.
Pharmacol Res ; 197: 106948, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37806602

RESUMO

The most recent and promising therapeutic strategies for inflammatory bowel disease (IBD) have engaged biologics targeting single effector components involved in major steps of the immune-inflammatory processes, such as tumor necrosis factor, interleukins or integrins. Nevertheless, these molecules have not yet met expectations regarding efficacy and safety, resulting in a significant percentage of refractory or relapsing patients. Thus, novel treatment options are urgently needed. The minor isoform of the complement inhibitor C4b-binding protein, C4BP(ß-), has been shown to confer a robust anti-inflammatory and immunomodulatory phenotype over inflammatory myeloid cells. Here we show that C4BP(ß-)-mediated immunomodulation can significantly attenuate the histopathological traits and preserve the intestinal epithelial integrity in dextran sulfate sodium (DSS)-induced murine colitis. C4BP(ß-) downregulated inflammatory transcripts, notably those related to neutrophil activity, mitigated circulating inflammatory effector cytokines and chemokines such as CXCL13, key in generating ectopic lymphoid structures, and, overall, prevented inflammatory immune cell infiltration in the colon of colitic mice. PRP6-HO7, a recombinant curtailed analogue with only immunomodulatory activity, achieved a similar outcome as C4BP(ß-), indicating that the therapeutic effect is not due to the complement inhibitory activity. Furthermore, both C4BP(ß-) and PRP6-HO7 significantly reduced, with comparable efficacy, the intrinsic and TLR-induced inflammatory markers in myeloid cells from both ulcerative colitis and Crohn's disease patients, regardless of their medication. Thus, the pleiotropic anti-inflammatory and immunomodulatory activity of PRP6-HO7, able to "reprogram" myeloid cells from the complex inflammatory bowel environment and to restore immune homeostasis, might constitute a promising therapeutic option for IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Animais , Humanos , Camundongos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Colite/induzido quimicamente , Colite/tratamento farmacológico , Imunomodulação , Inflamação , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/tratamento farmacológico , Células Mieloides
3.
Semin Cell Dev Biol ; 85: 143-152, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29155220

RESUMO

Complement and dendritic cells (DCs) share many functional features that drive the outcome of immune-inflammatory processes. Both have a sentinel function, acting as danger sensors specialized for a rapid, comprehensive and selective action against potential threats without damaging the healthy host cells. But while complement has been considered as a "master alarm" system poised for direct pathogen killing, DCs are regarded as "master regulators" or orchestrators of a vast range of effector immune cells for an effective immune response against threatening insults. The original definition of the complement system, coined to denote its auxiliary function to enhance or assist in the role of antibodies or phagocytes to clear microbes or damaged cells, envisaged an important crosstalk between the complement and the mononuclear phagocyte systems. More recent studies have shown that, depending on the microenvironmental conditions, several complement effectors are competent to influence the differentiation and/or function of different DC subsets toward immunogenicity or tolerance. In this review we will infer about the capability of complement activators and inhibitors to "condition" a tolerogenic and anti-inflammatory immune response by direct interaction with DC surface receptors, and about the implications of this knowledge to devise new complement-based therapeutic approaches for autoimmune pathologies.


Assuntos
Proteínas do Sistema Complemento/imunologia , Células Dendríticas/imunologia , Tolerância Imunológica/imunologia , Animais , Humanos
4.
Kidney Int ; 97(3): 551-566, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31982108

RESUMO

Lupus nephritis is a chronic autoimmune-inflammatory condition that can lead to end-stage kidney disease. Presently available immunosuppressive treatments for lupus nephritis are suboptimal and can induce significant side effects. Recently, we characterized a novel immunomodulatory activity of the minor isoform of the classical pathway complement inhibitor, C4BP(ß-). We show here that C4BP(ß-) treatment prevented the development of proteinuria and albuminuria, decreased significantly the formation of anti-dsDNA antibodies and, locally, mitigated renal glomerular IgG and C3 deposition and generation of apoptotic cells. There was a consequent histological improvement and increased survival in lupus-prone mice. The therapeutic efficacy of C4BP(ß-) was analogous to that of the broad-acting immunosuppressant cyclophosphamide. Remarkably, a comparative transcriptional profiling analysis revealed that the kidney gene expression signature resulting from C4BP(ß-) treatment turned out to be 10 times smaller than that induced by cyclophosphamide treatment. C4BP(ß-) immunomodulation induced significant downregulation of transcripts relevant to lupus nephritis indicating immunopathogenic cell infiltration, including activated T cells (Lat), B cells (Cd19, Ms4a1, Tnfrsf13c), inflammatory phagocytes (Irf7) and neutrophils (Prtn3, S100a8, S100a9). Furthermore, cytokine profiling and immunohistochemistry confirmed that C4BP(ß-), through systemic and local CXCL13 downregulation, was able to prevent ectopic lymphoid structures neogenesis in aged mice with lupus nephritis. Thus, due to its anti-inflammatory and immunomodulatory activities and high specificity, C4BP(ß-) could be considered for further clinical development in patients with systemic lupus erythematosus.


Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Animais , Antígenos de Histocompatibilidade , Humanos , Imunomodulação , Rim , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/prevenção & controle , Camundongos , Proteinúria
5.
J Immunol ; 196(10): 4274-90, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-27076676

RESUMO

The activation of the complement system is a key initiating step in the protective innate immune-inflammatory response against injury, although it may also cause harm if left unchecked. The structurally related soluble complement inhibitors C4b-binding protein (C4BP) and factor H (FH) exert a tight regulation of the classical/lectin and alternative pathways of complement activation, respectively, attenuating the activity of the C3/C5 convertases and, consequently, avoiding serious damage to host tissues. We recently reported that the acute-phase C4BP isoform C4BP lacking the ß-chain plays a pivotal role in the modulation of the adaptive immune responses. In this study, we demonstrate that FH acts in the early stages of monocyte to dendritic cell (DC) differentiation and is able to promote a distinctive tolerogenic and anti-inflammatory profile on monocyte-derived DCs (MoDCs) challenged by a proinflammatory stimulus. Accordingly, FH-treated and LPS-matured MoDCs are characterized by altered cytoarchitecture, resembling immature MoDCs, lower expression of the maturation marker CD83 and the costimulatory molecules CD40, CD80, and CD86, decreased production of key proinflammatory Th1-cytokines (IL-12, TNF-α, IFN-γ, IL-6, and IL-8), and preferential production of immunomodulatory mediators (IL-10 and TGF-ß). Moreover, FH-treated MoDCs show low Ag uptake and, when challenged with LPS, display reduced CCR7 expression and chemotactic migration, impaired CD4(+) T cell alloproliferation, inhibition of IFN-γ secretion by the allostimulated T cells, and, conversely, induction of CD4(+)CD127(low/negative)CD25(high)Foxp3(+) regulatory T cells. Thus, this novel noncanonical role of FH as an immunological brake able to directly affect the function of MoDCs in an inflammatory environment may exhibit therapeutic potential in hypersensitivity, transplantation, and autoimmunity.


Assuntos
Células Dendríticas/imunologia , Tolerância Imunológica , Inflamação/imunologia , Monócitos/imunologia , Antígenos CD/metabolismo , Diferenciação Celular , Células Cultivadas , Quimiotaxia , Proteína de Ligação ao Complemento C4b/imunologia , Fator H do Complemento/imunologia , Citocinas/imunologia , Endocitose , Humanos , Linfócitos T Reguladores/imunologia
6.
J Immunol ; 190(6): 2857-72, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23390292

RESUMO

The classical pathway complement regulator C4b-binding protein (C4BP) is composed of two polypeptides (α- and ß-chains), which form three plasma oligomers with different subunit compositions (α7ß1, α7ß0, and α6ß1). We show in this article that the C4BP α7ß0 isoform (hereafter called C4BP[ß(-)] [C4BP lacking the ß-chain]), overexpressed under acute-phase conditions, induces a semimature, tolerogenic state on human monocyte-derived dendritic cells (DCs) activated by a proinflammatory stimulus. C4BP isoforms containing ß-chain (α7ß1 and α6ß1; C4BP[ß(+)]) neither interfered with the normal maturation of DCs nor competed with C4BP(ß(-)) activity on these cells. Immature DCs (iDCs) treated with C4BP(ß(-)) retained high endocytic activity, but, upon LPS treatment, they did not upregulate surface expression of CD83, CD80, and CD86. Transcriptional profiling of these semimature DCs revealed that treatment with C4BP(ß(-)) prevented the induction of IDO and BIC-1, whereas TGF-ß1 expression was maintained to the level of iDCs. C4BP(ß(-))-treated DCs were also unable to release proinflammatory Th1 cytokines (IL-12, TNF-α, IFN-γ, IL-6, IL-8) and, conversely, increased IL-10 secretion. They prevented surface CCR7 overexpression and, accordingly, displayed reduced chemotaxis, being morphologically indistinguishable from iDCs. Moreover, C4BP(ß(-))-treated DCs failed to enhance allogeneic T cell proliferation, impairing IFN-γ production in these cells and, conversely, promoting CD4(+)CD127(low/neg)CD25(high)Foxp3(+) T cells. Deletion mutant analysis revealed that the complement control protein-6 domain of the α-chain is necessary for the tolerogenic activity of C4BP(ß(-)). Our data demonstrate a novel anti-inflammatory and immunomodulatory function of the complement regulator C4BP, suggesting a relevant role of the acute-phase C4BP(ß(-)) isoform in a number of pathophysiological conditions and potential applications in autoimmunity and transplantation.


Assuntos
Anti-Inflamatórios não Esteroides/química , Diferenciação Celular/imunologia , Proteína de Ligação ao Complemento C4b/fisiologia , Células Dendríticas/química , Células Dendríticas/imunologia , Antígenos de Histocompatibilidade/fisiologia , Diferenciação Celular/genética , Proteína de Ligação ao Complemento C4b/química , Proteína de Ligação ao Complemento C4b/genética , Células Dendríticas/patologia , Células HEK293 , Antígenos de Histocompatibilidade/química , Antígenos de Histocompatibilidade/genética , Humanos , Tolerância Imunológica/genética , Inflamação/genética , Inflamação/imunologia , Inflamação/prevenção & controle , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/fisiologia
7.
Inflamm Bowel Dis ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38518109

RESUMO

BACKGROUND: Limited data are available on the outcome of inflammatory bowel disease (IBD) in patients with solid organ transplantation (SOT). We describe the natural history of pre-existing IBD and de novo IBD after SOT. METHODS: This was a retrospective, multicenter study that included patients with pre-existing IBD at the time of SOT and patients with de novo IBD after SOT. The primary outcome was IBD progression, defined by escalation of medical treatment, surgical therapy, or hospitalization due to refractory IBD. Risk factors were identified using multivariate Cox proportional hazard analysis. RESULTS: A total of 177 patients (106 pre-existing IBD and 71 de novo IBD) were included. Most patients with pre-existing IBD (92.5%) were in remission before SOT. During follow-up, 32% of patients with pre-existing IBD had disease progression, with a median time between SOT and IBD progression of 2.2 (interquartile range, 1.3-4.6) years. In the de novo cohort, 55% of patients had disease progression with a median time to flare of 1.9 (interquartile range, 0.8-3.9) years after diagnosis. In the pre-existing IBD cohort, active IBD at the time of SOT (hazard ratio, 1.80; 95% confidence interval, 1.14-2.84; P = .012) and the presence of extraintestinal manifestations (hazard ratio, 3.10; 95% confidence interval, 1.47-6.54; P = .003) were predictive factors for IBD progression. CONCLUSIONS: One-third of patients with pre-existing IBD and about half of patients with de novo IBD have disease progression after SOT. Active IBD at the time of SOT and the presence of extraintestinal manifestations were identified as risk factors for IBD progression.

8.
Front Immunol ; 13: 883743, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35547734

RESUMO

C4b-binding protein (C4BP) is a well-known regulator of the complement system that holds additional and important activities unrelated to complement inhibition. Recently, we have described a novel immunomodulatory activity in the minor C4BP(ß-) isoform directly acting over inflammatory phagocytes. Here we show that incorporation of the ß-chain to the C4BP α-chain oligomer interferes with this immunomodulatory activity of C4BP. Moreover, an oligomeric form including only the complement control protein 6 (CCP6) domain of the C4BP α-chain (PRP6-HO7) is sufficient to "reprogram" monocyte-derived DCs (Mo-DCs) from a pro-inflammatory and immunogenic phenotype to an anti-inflammatory and tolerogenic state. PRP6-HO7 lacks complement regulatory activity but retains full immunomodulatory activity over inflammatory Mo-DCs induced by TLRs, characterized by downregulation of relevant surface markers such as CD83, HLA-DR, co-stimulatory molecules such as CD86, CD80 and CD40, and pro-inflammatory cytokines such as IL-12 and TNF-α. Furthermore, PRP6-HO7-treated Mo-DCs shows increased endocytosis, significantly reduced CCR7 expression and CCL21-mediated chemotaxis, and prevents T cell alloproliferation. Finally, PRP6-HO7 shows also full immunomodulatory activity over Mo-DCs isolated from lupus nephritis patients with active disease, even without further pro-inflammatory stimulation. Therefore PRP6-HO7, retaining the immunomodulatory activity of C4BP(ß-) and lacking its complement regulatory activity, might represent a promising and novel alternative to treat autoimmune diseases.


Assuntos
Proteína de Ligação ao Complemento C4b , Nefrite Lúpica , Proteína de Ligação ao Complemento C4b/metabolismo , Citocinas , Humanos , Imunomodulação , Monócitos/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-35897469

RESUMO

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide, causing 3.32 million deaths in 2019. COPD management has increasingly become a major component of general and hospital practice and has led to a different model of care. Nurse-led interventions have shown beneficial effects on COPD patient satisfaction and clinical outcomes. This systematic review was conducted to identify and assess nurse-led interventions in COPD patients in terms of mental, physical, and clinical status. The review was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. The relevance of each manuscript was assessed according to the inclusion criteria, and we retrieved full texts, as required, to reach our conclusions. Data extraction was performed independently by two reviewers, and the risk of bias was assessed using the Cochrane Risk of Bias tool. Forty-eight articles were included in the analysis, which focused on the management of COPD patients by hospital, respiratory and primary nursing care. Nursing management was shown to be highly effective in improving quality of life, emotional state, and pulmonary and physical capacity in COPD patients. In comparison, hospital and respiratory nurses carried out interventions with higher levels of effectiveness than community nurses.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Qualidade de Vida , Humanos , Papel do Profissional de Enfermagem , Satisfação do Paciente , Doença Pulmonar Obstrutiva Crônica/psicologia , Doença Pulmonar Obstrutiva Crônica/terapia , Autocuidado
10.
JMIR Form Res ; 5(10): e20970, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34709185

RESUMO

BACKGROUND: Despite unprecedented advances in worldwide access to the internet via smartphones, barriers to engaging hard-to-reach populations remain in many methods of health research. A potential avenue for conducting qualitative research is via participatory web-based media, including the free, popular social platform WhatsApp. However, despite the clear advantages of engaging with participants over a well-established web-based platform, logistical challenges remain. OBJECTIVE: This study aims to report evidence on the feasibility and acceptability of WhatsApp as a method to conduct focus groups. METHODS: A pilot focus group was conducted with Spanish-speaking women near the US-Mexico border. The content focus was knowledge and perceived risks for exposure to the Zika virus during pregnancy. RESULTS: Evidence was obtained regarding WhatsApp as a low-cost, logistically feasible methodology that resulted in rich qualitative data from a population that is often reticent to engage in traditional research. A total of 5 participants participated in a focus group, of whom all 5 consistently contributed to the focus group chat in WhatsApp, which was conducted over 3 consecutive days. CONCLUSIONS: The findings are noteworthy at a time when face-to-face focus groups, the gold standard, are risky or precluded by safe COVID-19 guidelines. Other implications include more applications and evaluations of WhatsApp for delivering one-on-one or group health education interventions on sensitive topics. This paper outlines the key steps and considerations for the replication or adaptation of methods.

11.
BMC Genomics ; 10: 113, 2009 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-19292924

RESUMO

BACKGROUND: Angiogenesis correlates with patient survival following acute ischaemic stroke, and survival of neurons is greatest in tissue undergoing angiogenesis. Angiogenesis is critical for the development of new microvessels and leads to re-formation of collateral circulation, reperfusion, enhanced neuronal survival and improved recovery. RESULTS: Here, we have isolated active (CD105/Flt-1 positive) and inactive (CD105/Flt-1 minus (n=5) micro-vessel rich-regions from stroke-affected and contralateral tissue of patients using laser-capture micro-dissection. Areas were compared for pro- and anti-angiogenic gene expression using targeted TaqMan microfluidity cards containing 46 genes and real-time PCR. Further analysis of key gene de-regulation was performed by immunohistochemistry to define localization and expression patterns of identified markers and de novo synthesis by human brain microvessel endothelial cells (HBMEC) was examined following oxygen-glucose deprivation (OGD). Our data revealed that seven pro-angiogenic genes were notably up-regulated in CD105 positive microvessel rich regions. These were, beta-catenin, neural cell adhesion molecule (NRCAM), matrix metalloproteinase-2 (MMP-2), tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), hepatocyte growth factor-alpha (HGF-alpha), monocyte chemottractant protein-1 (MCP-1) and and Tie-2 as well as c-kit. Immunohistochemistry demonstrated strong staining of MMP-2, HGF-alpha, MCP-1 and Tie-2 in stroke-associated regions of active remodeling in association with CD105 positive staining. In vitro, OGD stimulated production of Tie-2, MCP-1 and MMP-2 in HBMEC, demonstrated a de novo response to hypoxia. CONCLUSION: In this work we have identified concurrent activation of key angiogenic molecules associated with endothelial cell migration, differentiation and tube-formation, vessel stabilization and stem cell homing mechanisms in areas of revascularization. Therapeutic stimulation of these processes in all areas of damaged tissue might improve morbidity and mortality from stroke.


Assuntos
Proteínas Angiogênicas/metabolismo , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Acidente Vascular Cerebral/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Biomarcadores/sangue , Vasos Sanguíneos/química , Vasos Sanguíneos/metabolismo , Quimiocina CCL2/metabolismo , Endoglina , Células Endoteliais/metabolismo , Humanos , Imuno-Histoquímica , Metaloproteinase 2 da Matriz/metabolismo , Microdissecção/métodos , Neovascularização Patológica/metabolismo , Receptor TIE-2/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
12.
BMC Cell Biol ; 9: 47, 2008 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-18764931

RESUMO

BACKGROUND: Formation of haemorrhagic neovessels in the intima of developing atherosclerotic plaques is thought to significantly contribute to plaque instability resulting in thrombosis. C-reactive protein (CRP) is an acute phase reactant whose expression in the vascular wall, in particular, in reactive plaque regions, and circulating levels increase in patients at high risk of cardiovascular events. Although CRP is known to induce a pro-inflammatory phenotype in endothelial cells (EC) a direct role on modulation of angiogenesis has not been established. RESULTS: Here, we show that CRP is a powerful inducer of angiogenesis in bovine aortic EC (BAEC) and human coronary artery EC (HCAEC). CRP, at concentrations corresponding to moderate/high risk (1-5 microg/ml), induced a significant increase in proliferation, migration and tube-like structure formation in vitro and stimulated blood vessel formation in the chick chorioallantoic membrane assay (CAM). CRP treated with detoxi-gel columns retained such effects. Western blotting showed that CRP increased activation of early response kinase-1/2 (ERK1/2), a key protein involved in EC mitogenesis. Furthermore, using TaqMan Low-density Arrays we identified key pro-angiogenic genes induced by CRP among them were vascular endothelial cell growth factor receptor-2 (VEGFR2/KDR), platelet-derived growth factor (PDGF-BB), notch family transcription factors (Notch1 and Notch3), cysteine-rich angiogenic inducer 61 (CYR61/CCN1) and inhibitor of DNA binding/differentiation-1 (ID1). CONCLUSION: This data suggests a role for CRP in direct stimulation of angiogenesis and therefore may be a mediator of neovessel formation in the intima of vulnerable plaques.


Assuntos
Proteína C-Reativa/metabolismo , Células Endoteliais/metabolismo , Neovascularização Fisiológica , Transdução de Sinais , Animais , Bovinos , Proliferação de Células , Quimiotaxia , Vasos Coronários/metabolismo , Expressão Gênica , Humanos , Proteína Quinase 3 Ativada por Mitógeno , Fosforilação , Túnica Íntima/metabolismo
13.
Front Biosci ; 13: 6472-82, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18508673

RESUMO

Carotid atherosclerosis is a leading cause of cerebrovascular events. The control of cardiovascular risk factors, i.e. tobacco smoking, alcohol abuse, hypertension, dyslipidemia, diabetes and obesity proved to reduce number of fatal and non-fatal strokes but failed to prevent important number of them. Screening for biomarkers in individuals at high risk of symptomatic vascular disease helped to identify some of them. However, as disease is by its nature multifocal, global testing for biomarkers may have limited practical application. New imaging techniques, including direct visualization of artery metabolism, by 18-FDG-PET, has brought new tools to study local atherosclerosis progression and individual plaque metabolic activity. Advances in molecular biology helped to identify inflammatory genes and its strong link to angiogenesis. The later, is thought to play a key role in the transformation to unstable plaque. Studies of the complex role that plays angiogenesis in plaque development will help in future to design effective therapies addressed at the individual cell level. The purpose of the review is to bring new insights into complicated pathophysiology of carotid atherosclerosis.


Assuntos
Doenças das Artérias Carótidas/fisiopatologia , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/patologia , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Fibrina/metabolismo , Fibrinogênio/metabolismo , Humanos , Inflamação/patologia , Inflamação/fisiopatologia , Neovascularização Patológica , Acidente Vascular Cerebral/epidemiologia , Túnica Íntima/patologia , Túnica Íntima/fisiopatologia
14.
Front Biosci ; 13: 6483-90, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18508674

RESUMO

Hypoxia, angiogenesis and inflammation leads to plaque progression and remodelling and may significantly contribute towards plaque rupture and subsequent cerebrovascular events. Our aim was to study, markers of hypoxia and inflammation previously identified by microarray analysis, in atherosclerotic carotid arteries with low to moderate stenosis. We hoped to describe different cellular populations expressing the studied markers. The location of selected inflammatory molecules obtained as vascular transplants from organ donors were analysed by immunohistochemistry with monoclonal and polyclonal antibodies. Paraffin-embedded sections were cut and probed with antibodies recognizing active B and T-lymphocytes (CD30), hypoxia-inducible factor-1alpha, endoglin (CD105), Interleukin-6 and C-reactive protein. We observed a notable overexpression of HIF-1alpha in inflammatory and hypoxic areas of carotid arteries in all types of lesions from type II-V taken from the patients with carotid stenosis less than 50%. This suggests that HIF-1alpha may have a putative role in atherosclerosis progression and angiogenesis. Dynamic changes in the non-occluding plaques may explain some of the clinical events in patients with low to moderate carotid stenosis.


Assuntos
Doenças das Artérias Carótidas/patologia , Doenças das Artérias Carótidas/fisiopatologia , Inflamação/patologia , Inflamação/fisiopatologia , Antígenos CD/metabolismo , Autopsia , Proteína C-Reativa/metabolismo , Artérias Carótidas/patologia , Progressão da Doença , Endoglina , Humanos , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imuno-Histoquímica , Interleucina-6/metabolismo , Antígeno Ki-1/metabolismo , Neovascularização Patológica , Receptores de Superfície Celular/metabolismo , Doadores de Tecidos
15.
Front Biosci ; 13: 6491-500, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18508675

RESUMO

Cellular Prion Protein (PrPc) is a ubiquitous glycoprotein present on the surface of endothelial cells. Resting vascular endothelial cells show minimum expression of PrPc and can constitutively release PrPc. PrPc participates in cell survival, differentiation and angiogenesis. During development, neonatal brain endothelial cells transiently express PrPc. Our group recently reported upregulation of PrPc in microvessels from ischemic brain regions in stroke patients. Ischemia/hypoxia induces PrPc expression through the activation of extracellular signal-regulated kinase (ERK). All these data suggest that PrPc plays an important role in angiogenic responses. In addition, PrPc participates in cellular function in the central nervous system, since PrPc is also highly expressed in neurons. PrPc binds copper, suggesting a role in copper metabolism. PrPc also protects cells against oxidative stress and it seems to be involved in neuroprotection. Several studies have demonstrated that PrPc prevents cells from apoptosis and subsequent tissue damage. Moreover, PrPc plays an important role in the immune response. Here, we review the multiple functions of PrPc with a special attention to its recently reported role in angiogenesis.


Assuntos
Encéfalo/fisiologia , Proteínas PrPC/metabolismo , Animais , Encéfalo/citologia , Sobrevivência Celular , Cobre/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/fisiologia , Homeostase , Humanos , Ligantes , Neurônios/citologia , Neurônios/fisiologia , Estresse Oxidativo , Proteínas PrPC/genética , Valores de Referência , Transdução de Sinais , Sinapses/fisiologia , Zinco/metabolismo
16.
Acta Neuropathol ; 116(5): 537-45, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18810471

RESUMO

Normal cellular prion protein (PrP(C)) has multiple functions but its role in the development of atherosclerosis has not been studied. Our pilot microarray data showed increased expression of PrP(C) in tissue samples of complicated carotid lesions. Therefore in this study, we aimed to investigate its localisation within atherosclerotic arteries and its concentration in patient plasma. PrP(C) expression was examined using an enzyme immunometric assay (EIA) in plasma from patients undergoing endarterectomy. Carotid specimens and control vascular transplants were studied for PrP(C) and CD105 (endoglin, a marker of active vessels) expression by immunohistochemistry and real-time PCR. Patients with carotid disease had higher levels of plasma PrP(C) than the control group [4.35 ng/ml (n = 22; 3.1-5.3) vs. 1.95 ng/ml (n = 21; 1.1-2.5), P < 0.001]. Furthermore, CD105-positive plaques had higher PrP(C) expression which colocalized with CD105 in neovessels. There was a significant correlation between mRNA expression of PrP(C) and CD105 in tested plaques (P < 0.001; r = 0.7) supporting our immunohistochemical findings. We conclude that PrP(C) is expressed in carotid specimens and may be associated with neovessel growth or survival in these plaques. Our results suggest a role for PrP(C) in modulating neovessel formation in complicated plaques.


Assuntos
Antígenos CD/genética , Doenças das Artérias Carótidas/patologia , Microvasos/patologia , Proteínas PrPC/genética , Receptores de Superfície Celular/genética , Idoso , Antígenos CD/metabolismo , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Doenças das Artérias Carótidas/genética , Doenças das Artérias Carótidas/metabolismo , Endarterectomia das Carótidas/métodos , Endoglina , Feminino , Humanos , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Masculino , Microvasos/metabolismo , Pessoa de Meia-Idade , Proteínas PrPC/sangue , Proteínas PrPC/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Superfície Celular/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima/genética
17.
Front Immunol ; 9: 892, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29760704

RESUMO

The acute phase response is generated by an overwhelming immune-inflammatory process against infection or tissue damage, and represents the initial response of the organism in an attempt to return to homeostasis. It is mediated by acute phase proteins (APPs), an assortment of highly conserved plasma reactants of seemingly different functions that, however, share a common protective role from injury. Recent studies have suggested a crosstalk between several APPs and the mononuclear phagocyte system (MPS) in the resolution of inflammation, to restore tissue integrity and function. In fact, monocyte-derived dendritic cells (Mo-DCs), an integral component of the MPS, play a fundamental role both in the regulation of antigen-specific adaptive responses and in the development of immunologic memory and tolerance, particularly in inflammatory settings. Due to their high plasticity, Mo-DCs can be modeled in vitro toward a tolerogenic phenotype for the treatment of aberrant immune-inflammatory conditions such as autoimmune diseases and allotransplantation, with the phenotypic outcome of these cells depending on the immunomodulatory agent employed. Yet, recent immunotherapy trials have emphasized the drawbacks and challenges facing tolerogenic Mo-DC generation for clinical use, such as reduced therapeutic efficacy and limited in vivo stability of the tolerogenic activity. In this review, we will underline the potential relevance and advantages of APPs for tolerogenic DC production with respect to currently employed immunomodulatory/immunosuppressant compounds. A further understanding of the mechanisms of action underlying the moonlighting immunomodulatory activities exhibited by several APPs over DCs could lead to more efficacious, safe, and stable protocols for precision tolerogenic immunotherapy.


Assuntos
Proteínas de Fase Aguda/imunologia , Células Dendríticas/imunologia , Tolerância Imunológica/imunologia , Animais , Humanos
18.
J Neurosurg ; 131(1): 72-79, 2018 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-30052155

RESUMO

OBJECTIVE: Carotid artery atherosclerosis is a major cause of ischemic stroke. However, reliable criteria to identify patients with high-risk carotid plaques beyond the severity of stenosis are still lacking. Circulating microRNAs (miRNAs) are being postulated as biomarkers for a variety of vascular immune-inflammatory diseases. The authors investigated whether cell-free circulating miR-638, highly expressed in vascular smooth muscle cells and implicated in proliferative vascular diseases, is associated with vulnerable atherosclerotic plaques in high-risk patients with advanced carotid artery stenosis undergoing carotid endarterectomy (CEA). METHODS: The authors conducted a prospective study in 22 consecutive symptomatic patients with high-grade carotid stenosis undergoing CEA and 36 age- and sex-matched patients without ischemic stroke history or carotid atherosclerosis (control group). In addition, they reviewed data from a historical group of 9 CEA patients who underwent long-term follow-up after revascularization. Total RNA was isolated from all serum samples, and relative miR-638 expression levels were detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and compared among groups. A correlation analysis of serum miR-638 levels with vascular risk factors and treatments, and with plaque features, was performed. The ability of serum miR-638 to discriminate between the non-CEA control group and the different CEA groups was assessed by receiver operating characteristic evaluation. A logistic regression model was employed to examine the association between stratified CEA patients and serum miR-638 levels. RESULTS: Serum levels of miR-638 were significantly lower in symptomatic CEA patients (p = 0.009) and particularly in the subgroup of CEA patients who had experienced stroke (p = 0.0006) than in non-CEA controls. Discrimination of high-risk plaques was accurate (area under the curve [AUC] 0.66 for symptomatic CEA patients in general and 0.76 for those who had experienced stroke). When only patients with high cardiovascular risk were considered, the diagnostic value of serum miR-638 from symptomatic CEA patients and CEA patients who had experienced stroke improved (AUC 0.79 and 0.85). Moreover, serum miR-638 was negatively correlated with the occurrence of stroke, smoker status, presence of bilateral pathology, coronary artery disease, and cholesterol treatment; and with the high-risk fibroatheroma plaques extracted from CEA patients. Multivariate logistic regression analysis demonstrated that serum miR-638 was an independent predictor of plaque instability. Furthermore, serum miR-638 appeared to attain good discrimination for atherosclerotic stenosis in CEA patients based on analysis of blood samples obtained in the historical group before and 5 years after intervention (p = 0.04) (AUC = 0.79). CONCLUSIONS: According to this preliminary proof-of-concept study, serum miR-638 might constitute a promising noninvasive biomarker associated with plaque vulnerability and ischemic stroke, particularly in individuals with elevated cardiovascular risk.

19.
Genome Biol ; 17: 4, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26758199

RESUMO

BACKGROUND: The role of cytokines in establishing specific transcriptional programmes in innate immune cells has long been recognized. However, little is known about how these extracellular factors instruct innate immune cell epigenomes to engage specific differentiation states. Human monocytes differentiate under inflammatory conditions into effector cells with non-redundant functions, such as dendritic cells and macrophages. In this context, interleukin 4 (IL-4) and granulocyte macrophage colony-stimulating factor (GM-CSF) drive dendritic cell differentiation, whereas GM-CSF alone leads to macrophage differentiation. RESULTS: Here, we investigate the role of IL-4 in directing functionally relevant dendritic-cell-specific DNA methylation changes. A comparison of DNA methylome dynamics during differentiation from human monocytes to dendritic cells and macrophages identified gene sets undergoing dendritic-cell-specific or macrophage-specific demethylation. Demethylation is TET2-dependent and is essential for acquiring proper dendritic cell and macrophage identity. Most importantly, activation of the JAK3-STAT6 pathway, downstream of IL-4, is required for the acquisition of the dendritic-cell-specific demethylation and expression signature, following STAT6 binding. A constitutively activated form of STAT6 is able to bypass IL-4 upstream signalling and instruct dendritic-cell-specific functional DNA methylation changes. CONCLUSIONS: Our study is the first description of a cytokine-mediated sequence of events leading to direct gene-specific demethylation in innate immune cell differentiation.


Assuntos
Diferenciação Celular/genética , Metilação de DNA/genética , Interleucina-4/genética , Fator de Transcrição STAT6/genética , Proteínas de Ligação a DNA/genética , Células Dendríticas/citologia , Dioxigenases , Regulação da Expressão Gênica , Humanos , Imunidade Inata/genética , Interleucina-4/metabolismo , Fator Estimulador de Colônias de Macrófagos/genética , Fator Estimulador de Colônias de Macrófagos/metabolismo , Monócitos/citologia , Monócitos/metabolismo , Proteínas Proto-Oncogênicas/genética , Fator de Transcrição STAT6/metabolismo
20.
Sci. agric ; 77(2): e20180038, 2020. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1497839

RESUMO

Sugarcane orange rust caused by Puccinia kuehnii has recently become an important disease in sugarcane crops and its spread is causing great concern to growers. In this study, we analyzed spores from symptomatic orange rust sugarcane leaves collected in multiple locations in Cuba in a 4-year-period in order to characterize morphological traits of P. kuehnii, establish an adequate molecular technique to characterize it, and determine its infection court in sugarcane. Orange rust caused by P. kuehnii was confirmed by polymerase chain reaction (PCR) and morphological characterization. AFLP markers detected high diversity in P. kuenhnii samples. Sequencing of rDNA regions, as expected, did not reveal differences and SSR markers designed for P. melanocephala could not be transferred to P. kuehnii. In addition to stomata, entry through prickles was also detected as a new infection court in sugarcane. Although the presence of pustules on the adaxial leaf surface was frequently detected, no clear correlation between this presence and density of stomata and/or prickles was found.


Assuntos
Fungos , Saccharum/microbiologia , Reação em Cadeia da Polimerase
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