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1.
Commun Chem ; 6(1): 237, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919467

RESUMO

Cathepsin D is a protease that is an effector in the immune response of macrophages, yet to date, only a limited number of probes have been developed for its detection. Herein, we report a water soluble, highly sensitive, pH insensitive fluorescent probe for the detection of Cathepsin D activity that provides a strong OFF/ON signal upon activation and with bright emission at 515 nm. The probe was synthesised using a combination of solid and solution-phase chemistries, with probe optimisation to increase its water solubility and activation kinetics by addition of a long PEG chain (5 kDa) at the C-terminus. A BODIPY fluorophore allowed detection of Cathepsin D across a wide pH range, important as the protease is active both at the low pH found in lysosomes and also in higher pH phagolysosomes, and in the cytosol. The probe was successfully used to detect Cathepsin D activity in macrophages challenged by exposure to bacteria.

2.
Am J Respir Crit Care Med ; 207(8): 998-1011, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36724365

RESUMO

Rationale: Chronic obstructive pulmonary disease (COPD) is a disease characterized by persistent airway inflammation and disordered macrophage function. The extent to which alterations in macrophage bioenergetics contribute to impaired antioxidant responses and disease pathogenesis has yet to be fully delineated. Objectives: Through the study of COPD alveolar macrophages (AMs) and peripheral monocyte-derived macrophages (MDMs), we sought to establish if intrinsic defects in core metabolic processes drive macrophage dysfunction and redox imbalance. Methods: AMs and MDMs from donors with COPD and healthy donors underwent functional, metabolic, and transcriptional profiling. Measurements and Main Results: We observed that AMs and MDMs from donors with COPD display a critical depletion in glycolytic- and mitochondrial respiration-derived energy reserves and an overreliance on glycolysis as a source for ATP, resulting in reduced energy status. Defects in oxidative metabolism extend to an impaired redox balance associated with defective expression of the NADPH-generating enzyme, ME1 (malic enzyme 1), a known target of the antioxidant transcription factor NRF2 (nuclear factor erythroid 2-related factor 2). Consequently, selective activation of NRF2 resets the COPD transcriptome, resulting in increased generation of TCA cycle intermediaries, improved energetic status, favorable redox balance, and recovery of macrophage function. Conclusions: In COPD, an inherent loss of metabolic plasticity leads to metabolic exhaustion and reduced redox capacity, which can be rescued by activation of the NRF2 pathway. Targeting these defects, via NRF2 augmentation, may therefore present an attractive therapeutic strategy for the treatment of the aberrant airway inflammation described in COPD.


Assuntos
Fator 2 Relacionado a NF-E2 , Doença Pulmonar Obstrutiva Crônica , Humanos , Macrófagos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Malato Desidrogenase/metabolismo
3.
Sci Rep ; 13(1): 2271, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36755116

RESUMO

The human skin barrier, a biological imperative, is impaired in inflammatory skin diseases such as atopic dermatitis (AD). Staphylococcus aureus is associated with AD lesions and contributes to pathological inflammation and further barrier impairment. S. aureus secretes extracellular proteases, such as V8 (or 'SspA'), which cleave extracellular proteins to reduce skin barrier. Previous studies demonstrated that the host defence peptide human beta-defensin 2 (HBD2) prevented V8-mediated damage. Here, the mechanism of HBD2-mediated barrier protection in vitro is examined. Application of exogenous HBD2 provided protection against V8, irrespective of timeline of application or native peptide folding, raising the prospect of simple peptide analogues as therapeutics. HBD2 treatment, in context of V8-mediated damage, modulated the proteomic/secretomic profiles of HaCaT cells, altering levels of specific extracellular matrix proteins, potentially recovering V8 damage. However, HBD2 alone did not substantially modulate cellular proteomic/secretomics profiles in the absence of damage, suggesting possible therapeutic targeting of lesion damage sites only. HBD2 did not show any direct protease inhibition or induce expression of known antiproteases, did not alter keratinocyte migration or proliferation, or form protective nanonet structures. These data validate the barrier-protective properties of HBD2 in vitro and establish key protein datasets for further targeted mechanistic analyses.


Assuntos
Dermatite Atópica , beta-Defensinas , Humanos , beta-Defensinas/farmacologia , beta-Defensinas/metabolismo , Staphylococcus aureus/metabolismo , Proteômica , Pele/metabolismo , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/patologia , Proteínas
4.
Clin Neurol Neurosurg ; 224: 107533, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36434898

RESUMO

The authors report a case in which an acute thrombosis of a pre-existing arterial stent occurs in a patient's lower extremity during a lumbar spinal fusion surgery. The event was detected by acute changes in somatosensory evoked potentials (SSEPs) which were being monitored during the procedure. The neurophysiology technologist reported a 10 % increased latency and 50 % loss of amplitude in the left posterior tibial nerve recordings. While still in the operating room, further investigation, including doppler and arteriogram, demonstrated a complete occlusion of one of the two contiguous stents within the superficial femoral artery (SFA). A vascular surgeon was then able to emergently perform trans-arterial thrombectomy and restore flow through the extremity while still in the operating room. The observed events demonstrate the ability of SSEP monitoring to potentially detect arterial occlusion early, allowing for a rapid diagnosis and expedient treatment, in this case immediate, thus avoiding significant limb threatening morbidity.


Assuntos
Arteriopatias Oclusivas , Monitorização Intraoperatória , Humanos , Monitorização Intraoperatória/métodos , Potenciais Somatossensoriais Evocados/fisiologia , Extremidade Inferior , Arteriopatias Oclusivas/diagnóstico , Arteriopatias Oclusivas/cirurgia , Stents , Potencial Evocado Motor/fisiologia
5.
Front Pharmacol ; 13: 949264, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36003515

RESUMO

Rationale: Galectin-3 (Gal-3) drives fibrosis during chronic lung injury, however, its role in acute lung injury (ALI) remains unknown. Effective pharmacological therapies available for ALI are limited; identifying novel concepts in treatment is essential. GB0139 is a Gal-3 inhibitor currently under clinical investigation for the treatment of idiopathic pulmonary fibrosis. We investigate the role of Gal-3 in ALI and evaluate whether its inhibition with GB0139 offers a protective role. The effect of GB0139 on ALI was explored in vivo and in vitro. Methods: The pharmacokinetic profile of intra-tracheal (i.t.) GB0139 was investigated in C57BL/6 mice to support the daily dosing regimen. GB0139 (1-30 µg) was then assessed following acute i.t. lipopolysaccharide (LPS) and bleomycin administration. Histology, broncho-alveolar lavage fluid (BALf) analysis, and flow cytometric analysis of lung digests and BALf were performed. The impact of GB0139 on cell activation and apoptosis was determined in vitro using neutrophils and THP-1, A549 and Jurkat E6 cell lines. Results: GB0139 decreased inflammation severity via a reduction in neutrophil and macrophage recruitment and neutrophil activation. GB0139 reduced LPS-mediated increases in interleukin (IL)-6, tumor necrosis factor alpha (TNFα) and macrophage inflammatory protein-1-alpha. In vitro, GB0139 inhibited Gal-3-induced neutrophil activation, monocyte IL-8 secretion, T cell apoptosis and the upregulation of pro-inflammatory genes encoding for IL-8, TNFα, IL-6 in alveolar epithelial cells in response to mechanical stretch. Conclusion: These data indicate that Gal-3 adopts a pro-inflammatory role following the early stages of lung injury and supports the development of GB0139, as a potential treatment approach in ALI.

6.
PLoS Biol ; 20(8): e3001554, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36026478

RESUMO

Multiple sclerosis (MS) is a highly prevalent demyelinating autoimmune condition; the mechanisms regulating its severity and progression are unclear. The IL-17-producing Th17 subset of T cells has been widely implicated in MS and in the mouse model, experimental autoimmune encephalomyelitis (EAE). However, the differentiation and regulation of Th17 cells during EAE remain incompletely understood. Although evidence is mounting that the antimicrobial peptide cathelicidin profoundly affects early T cell differentiation, no studies have looked at its role in longer-term T cell responses. Now, we report that cathelicidin drives severe EAE disease. It is released from neutrophils, microglia, and endothelial cells throughout disease; its interaction with T cells potentiates Th17 differentiation in lymph nodes and Th17 to exTh17 plasticity and IFN-γ production in the spinal cord. As a consequence, mice lacking cathelicidin are protected from severe EAE. In addition, we show that cathelicidin is produced by the same cell types in the active brain lesions in human MS disease. We propose that cathelicidin exposure results in highly activated, cytokine-producing T cells, which drive autoimmunity; this is a mechanism through which neutrophils amplify inflammation in the central nervous system.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Animais , Peptídeos Catiônicos Antimicrobianos , Peptídeos Antimicrobianos , Diferenciação Celular , Encefalomielite Autoimune Experimental/patologia , Células Endoteliais/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Células Th1/metabolismo , Células Th1/patologia , Células Th17/metabolismo , Catelicidinas
7.
Front Cell Dev Biol ; 10: 905315, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693926

RESUMO

Cyclin-dependent kinase (CDK) inhibitor drugs (CDKi), such as R-roscovitine and AT7519, induce neutrophil apoptosis in vitro and enhance the resolution of inflammation in a number of in vivo models. This class of compounds are potential novel therapeutic agents that could promote the resolution of acute and chronic inflammatory conditions where neutrophil activation contributes to tissue damage and aberrant tissue repair. In this study we investigated CDKi effects on macrophage pro-inflammatory mediator production and viability. Treatment of human monocyte-derived macrophages (MDMs) with the CDKi AT7519 and R-roscovitine at concentrations that induce neutrophil apoptosis had no significant effect on control or LPS-activated MDM apoptosis and viability, and did not detrimentally affect MDM efferocytosis of apoptotic cells. In addition, enhanced efferocytosis, induced by the glucocorticoid dexamethasone, was also unaffected after a short time treatment with R-roscovitine. Macrophage cytokine responses to inflammatory stimuli are also of importance during inflammation and resolution. As a key target of CDKi, CDK9, is involved in protein transcription via the RNA polymerase II complex, we investigated the effect of CDKi drugs on cytokine production. Our data show that treatment with AT7519 significantly downregulated expression and release of key MDM cytokines IL-6, TNF, IL-10 and IL-1ß, as well as markers of pro-inflammatory macrophage polarisation. R-Roscovitine was also able to downregulate inflammatory cytokine protein secretion from MDMs. Using siRNA transfection, we demonstrate that genetic knock-down of CDK9 replicates these findings, reducing expression and release of pro-inflammatory cytokines. Furthermore, overexpression of CDK9 in THP-1 cells can promote a pro-inflammatory phenotype in these cells, suggesting that CDK9 plays an important role in the inflammatory phenotype of macrophages. Overall, this study demonstrates that pharmacological and genetic targeting of CDK9 inhibits an inflammatory phenotype in human MDMs. As such these data indicate that CDK9 may be key to therapeutically targeting pro-inflammatory macrophage functions during chronic inflammation.

8.
Oncoimmunology ; 8(8): 1608106, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413918

RESUMO

Immunization of patients with autologous, ex vivo matured dendritic cell (DC) preparations, in order to prime antitumor T-cell responses, is the focus of intense research. Despite progress and approval of clinical approaches, significant enhancement of these personalized immunotherapies is urgently needed to improve efficacy. We show that immunotherapeutic murine and human DC, generated in the presence of the antimicrobial host defense peptide LL-37, have dramatically enhanced expansion and differentiation of cells with key features of the critical CD103+/CD141+ DC subsets, including enhanced cross-presentation and co-stimulatory capacity, and upregulation of CCR7 with improved migratory capacity. These LL-37-DC enhanced proliferation, activation and cytokine production by CD8+ (but not CD4+) T cells in vitro and in vivo. Critically, tumor antigen-presenting LL-37-DC increased migration of primed, activated CD8+ T cells into established squamous cell carcinomas in mice, and resulted in tumor regression. This advance therefore has the potential to dramatically enhance DC immunotherapy protocols.

9.
Sci Rep ; 9(1): 7356, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31089176

RESUMO

Preterm birth, defined as delivery before 37 weeks of gestation, is the leading cause of neonatal mortality and morbidity. Infection and inflammation are frequent antecedents of spontaneous preterm birth. Cathelicidin, an antimicrobial host defence peptide, is induced by infection and inflammation and although expressed in the reproductive tract and fetal tissues, its role in the pathogenesis of spontaneous preterm birth is unknown. Here we demonstrate that cathelicidin expression is increased at RNA and protein level in the mouse uterus in a model of inflammation-induced labour, where ultrasound guided intrauterine injection of lipopolysaccharide (LPS) at E17 stimulates preterm delivery within 24 hours. Cathelicidin-deficient (Camp-/-) mice are less susceptible to preterm delivery than wild type mice following intrauterine injection of 1 µg of LPS, and this is accompanied by a decrease in circulating IL-6, an inflammatory mediator implicated in the onset of labour. We also show that the proportion of cathelicidin expressing cells in the myometrium is higher in samples obtained from women in labour at term than pre-labour. Together, these data suggest that cathelicidin has roles in mediating pro-inflammatory responses in a murine model of inflammation-induced labour, and in human term labour.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Inflamação/imunologia , Miométrio/patologia , Trabalho de Parto Prematuro/imunologia , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/imunologia , Cesárea , Modelos Animais de Doenças , Feminino , Humanos , Inflamação/sangue , Inflamação/complicações , Inflamação/patologia , Interleucina-6/sangue , Interleucina-6/imunologia , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Knockout , Miométrio/imunologia , Miométrio/cirurgia , Trabalho de Parto Prematuro/sangue , Trabalho de Parto Prematuro/patologia , Gravidez , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Catelicidinas
10.
PLoS Pathog ; 15(4): e1007694, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30978238

RESUMO

Pulmonary infections are a major global cause of morbidity, exacerbated by an increasing threat from antibiotic-resistant pathogens. In this context, therapeutic interventions aimed at protectively modulating host responses, to enhance defence against infection, take on ever greater significance. Pseudomonas aeruginosa is an important multidrug-resistant, opportunistic respiratory pathogen, the clearance of which can be enhanced in vivo by the innate immune modulatory properties of antimicrobial host defence peptides from the cathelicidin family, including human LL-37. Initially described primarily as bactericidal agents, cathelicidins are now recognised as multifunctional antimicrobial immunomodulators, modifying host responses to pathogens, but the key mechanisms involved in these protective functions are not yet defined. We demonstrate that P. aeruginosa infection of airway epithelial cells promotes extensive infected cell internalisation of LL-37, in a manner that is dependent upon epithelial cell interaction with live bacteria, but does not require bacterial Type 3 Secretion System (T3SS). Internalised LL-37 acts as a second signal to induce inflammasome activation in airway epithelial cells, which, in contrast to myeloid cells, are relatively unresponsive to P. aeruginosa. We demonstrate that this is mechanistically dependent upon cathepsin B release, and NLRP3-dependent activation of caspase 1. These result in LL-37-mediated release of IL-1ß and IL-18 in a manner that is synergistic with P. aeruginosa infection, and can induce caspase 1-dependent death of infected epithelial cells, and promote neutrophil chemotaxis. We propose that cathelicidin can therefore act as a second signal, required by P. aeruginosa infected epithelial cells to promote an inflammasome-mediated altruistic cell death of infection-compromised epithelial cells and act as a "fire alarm" to enhance rapid escalation of protective inflammatory responses to an uncontrolled infection. Understanding this novel modulatory role for cathelicidins, has the potential to inform development of novel therapeutic strategies to antibiotic-resistant pathogens, harnessing innate immunity as a complementation or alternative to current interventions.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Catelicidinas/farmacologia , Células Epiteliais/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/imunologia , Sistema Respiratório/imunologia , Animais , Caspase 1/metabolismo , Comunicação Celular , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/imunologia , Inflamassomos/efeitos dos fármacos , Inflamassomos/imunologia , Inflamassomos/metabolismo , Interleucina-18/genética , Interleucina-18/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Sistema Respiratório/efeitos dos fármacos , Sistema Respiratório/metabolismo
11.
Cancer Res ; 79(7): 1480-1492, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30674531

RESUMO

A combination therapy approach is required to improve tumor immune infiltration and patient response to immune checkpoint inhibitors that target negative regulatory receptors. Galectin-3 is a ß-galactoside-binding lectin that is highly expressed within the tumor microenvironment of aggressive cancers and whose expression correlates with poor survival particularly in patients with non-small cell lung cancer (NSCLC). To examine the role of galectin-3 inhibition in NSCLC, we tested the effects of galectin-3 depletion using genetic and pharmacologic approaches on syngeneic mouse lung adenocarcinoma and human lung adenocarcinoma xenografts. Galectin-3-/- mice developed significantly smaller and fewer tumors and metastases than syngeneic C57/Bl6 wild-type mice. Macrophage ablation retarded tumor growth, whereas reconstitution with galectin-3-positive bone marrow restored tumor growth in galectin-3-/- mice, indicating that macrophages were a major driver of the antitumor response. Oral administration of a novel small molecule galectin-3 inhibitor GB1107 reduced human and mouse lung adenocarcinoma growth and blocked metastasis in the syngeneic model. Treatment with GB1107 increased tumor M1 macrophage polarization and CD8+ T-cell infiltration. Moreover, GB1107 potentiated the effects of a PD-L1 immune checkpoint inhibitor to increase expression of cytotoxic (IFNγ, granzyme B, perforin-1, Fas ligand) and apoptotic (cleaved caspase-3) effector molecules. In summary, galectin-3 is an important regulator of lung adenocarcinoma progression. The novel galectin-3 inhibitor presented could provide an effective, nontoxic monotherapy or be used in combination with immune checkpoint inhibitors to boost immune infiltration and responses in lung adenocarcinoma and potentially other aggressive cancers. SIGNIFICANCE: A novel and orally active galectin-3 antagonist inhibits lung adenocarcinoma growth and metastasis and augments response to PD-L1 blockade.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/79/7/1480/F1.large.jpg.


Assuntos
Adenocarcinoma de Pulmão/patologia , Antígeno B7-H1/antagonistas & inibidores , Proliferação de Células/efeitos dos fármacos , Galectina 3/antagonistas & inibidores , Neoplasias Pulmonares/patologia , Adenocarcinoma de Pulmão/metabolismo , Administração Oral , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Feminino , Galectina 3/genética , Galectina 3/fisiologia , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Nus
12.
Am J Respir Crit Care Med ; 198(7): 880-890, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29733693

RESUMO

RATIONALE: Excessive neutrophilic airway inflammation is the central feature of bronchiectasis, but little is known about neutrophils in bronchiectasis. OBJECTIVES: To assess blood neutrophil phenotype in patients with bronchiectasis while stable and during exacerbations. METHODS: In the clinically stable arm of this study, there were eight healthy volunteers, eight patients with mild bronchiectasis, and eight patients with severe bronchiectasis. In addition, six patients with severe bronchiectasis were compared with six patients with community-acquired pneumonia at the start and end of an exacerbation. We assessed neutrophils for spontaneous apoptosis, cell surface marker expression, degranulation, reactive oxygen species generation, phagocytosis, and killing of Pseudomonas aeruginosa (PAO1). In addition, blood neutrophil function was compared with airway neutrophil function in bronchiectasis. MEASUREMENTS AND MAIN RESULTS: In stable bronchiectasis, compared with healthy volunteers, blood neutrophils had significantly prolonged viability, delayed apoptosis, increased CD62L shedding, upregulated CD11b expression, increased myeloperoxidase release, and impaired neutrophil phagocytosis and killing of PAO1. Bronchiectatic airway neutrophils had significantly lower bacterial phagocytosis and killing than their matched autologous blood neutrophils. Both blood and airway neutrophil phagocytosis and killing were impaired at the start of an exacerbation and improved following antibiotic treatment. In pneumonia, there was a significant improvement in phagocytosis and killing after treatment with antibiotics. During infections, there was no difference in phagocytosis, but there was significantly increased bacterial killing at the start and end of infection in pneumonia compared with bronchiectasis exacerbations. CONCLUSIONS: In bronchiectasis stable state, peripheral blood neutrophils are reprogrammed and have prolonged survival. This impairs their functional ability of bacterial phagocytosis and killing, thereby perpetuating the vicious circle in bronchiectasis.


Assuntos
Apoptose/fisiologia , Bronquiectasia/sangue , Bronquiectasia/fisiopatologia , Neutrófilos/citologia , Neutrófilos/metabolismo , Análise de Variância , Broncoscopia/métodos , Estudos de Casos e Controles , Progressão da Doença , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Fagocitose/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Valores de Referência , Sensibilidade e Especificidade , Índice de Gravidade de Doença
13.
J Invest Dermatol ; 138(10): 2264-2274, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29723492

RESUMO

Chronic wounds cause significant patient morbidity and mortality. A key factor in their etiology is microbial infection, yet skin host-microbiota interactions during wound repair remain poorly understood. Microbiome profiles of noninfected human chronic wounds are associated with subsequent healing outcome. Furthermore, poor clinical healing outcome was associated with increased local expression of the pattern recognition receptor NOD2. To investigate NOD2 function in the context of cutaneous healing, we treated mice with the NOD2 ligand muramyl dipeptide and analyzed wound repair parameters and expression of antimicrobial peptides. Muramyl dipeptide treatment of littermate controls significantly delayed wound repair associated with reduced re-epithelialization, heightened inflammation, and up-regulation of murine ß-defensins 1, 3, and particularly 14. We postulated that although murine ß-defensin 14 might affect local skin microbial communities, it may further affect other healing parameters. Indeed, exogenously administered murine ß-defensin 14 directly delayed mouse primary keratinocyte scratch wound closure in vitro. To further explore the role of murine ß-defensin 14 in wound repair, we used Defb14-/- mice and showed they had a global delay in healing in vivo, associated with alterations in wound microbiota. Taken together, these studies suggest a key role for NOD2-mediated regulation of local skin microbiota, which in turn affects chronic wound etiology.


Assuntos
Microbiota/genética , Proteína Adaptadora de Sinalização NOD2/genética , RNA/genética , Regulação para Cima , Cicatrização/genética , Ferimentos e Lesões/genética , beta-Defensinas/genética , Adulto , Animais , Células Cultivadas , Modelos Animais de Doenças , Feminino , Interações entre Hospedeiro e Microrganismos , Humanos , Queratinócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Adaptadora de Sinalização NOD2/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Ativação Transcricional , Ferimentos e Lesões/metabolismo , Ferimentos e Lesões/patologia , beta-Defensinas/metabolismo
14.
J Invest Dermatol ; 137(1): 95-105, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27702565

RESUMO

Atopic dermatitis (AD) is a common chronic inflammatory skin disease that results in significant morbidity. A hallmark of AD is disruption of the critical barrier function of upper epidermal layers, causatively linked to environmental stimuli, genetics, and infection, and a critical current target for the development of new therapeutic and prophylactic interventions. Staphylococcus aureus is an AD-associated pathogen producing virulence factors that induce skin barrier disruption in vivo and contribute to AD pathogenesis. We show, using immortalized and primary keratinocytes, that S. aureus protease SspA/V8 is the dominant secreted factor (in laboratory and AD clinical strains of S. aureus) inducing barrier integrity impairment and tight junction damage. V8-induced integrity damage was inhibited by an IL-1ß-mediated mechanism, independent of effects on claudin-1. Induction of keratinocyte expression of the antimicrobial/host defense peptide human ß-defensin 2 (hBD2) was found to be the mechanism underpinning this protective effect. Endogenous hBD2 expression was required and sufficient for protection against V8 protease-mediated integrity damage, and exogenous application of hBD2 was protective. This modulatory property of hBD2, unrelated to antibacterial effects, gives new significance to the defective induction of hBD2 in the barrier-defective skin lesions of AD and indicates therapeutic potential.


Assuntos
Dermatite Atópica/microbiologia , Interleucina-1beta/metabolismo , Infecções Cutâneas Estafilocócicas/metabolismo , Staphylococcus aureus/patogenicidade , beta-Defensinas/metabolismo , Análise de Variância , Apoptose , Western Blotting , Células Cultivadas , Dermatite Atópica/fisiopatologia , Ensaio de Imunoadsorção Enzimática , Células Epidérmicas , Epiderme/patologia , Humanos , Queratinócitos/metabolismo , Queratinócitos/microbiologia , Peptídeo Hidrolases/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Infecções Cutâneas Estafilocócicas/patologia , Staphylococcus aureus/enzimologia
15.
BMJ Open Respir Res ; 1(1): e000046, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25478190

RESUMO

OBJECTIVES: The observation that pathogenic bacteria are commonly tolerated in the human nose, yet drive florid inflammation in the lung, is poorly understood, partly due to limited availability of primary human cells from each location. We compared responses to bacterial virulence factors in primary human nasal and alveolar cells, and characterised the distribution of Toll-interacting protein (TOLLIP; an inhibitor of Toll-like receptor (TLR) signalling) in the human respiratory tract. METHODS: Primary cells were isolated from nasal brushings and lung tissue taken from patients undergoing pulmonary resection. Cells were exposed to lipopolysaccharide, lipoteichoic acid, peptidoglycan, CpG-C DNA or tumour necrosis factor (TNF). Cytokines were measured in cell supernatants. TOLLIP was characterised using quantitative real-time PCR and immunofluorescence. RESULTS: In primary alveolar, but not primary nasal, cells peptidoglycan significantly increased secretion of interleukin (IL)-1ß, IL-6, IL-8, IL-10 and TNF. TLR2 expression was significantly higher in alveolar cells and correlated with IL-8 production. TOLLIP expression was significantly greater in nasal cells. CONCLUSION: In conclusion, primary human alveolar epithelial cells are significantly more responsive to peptidoglycan than primary nasal epithelial cells. This may partly be explained by differential TLR2 expression. TOLLIP is expressed widely in the human respiratory tract, and may contribute to the regulation of inflammatory responses.

16.
PLoS One ; 9(8): e103434, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25089904

RESUMO

hCAP18/LL-37 is the sole human cathelicidin; a family of host defence peptides with key roles in innate host defence. hCAP18/LL-37 is expressed primarily by neutrophils and epithelial cells, but its production and function in the lower genital tract is largely uncharacterised. Despite the significant roles for cathelicidin in multiple organs and inflammatory processes, its impact on infections that could compromise fertility and pregnancy is unknown. The aim of this study was to investigate cathelicidin production, regulation and function in the cervix. hCAP18/LL-37 was found to be present in cervicovaginal secretions collected from women in the first trimester of pregnancy and to be expressed at significantly higher levels in samples from women with alterations in vaginal bacterial flora characteristic of bacterial vaginosis. In endocervical epithelial cell lines, expression of the gene encoding hCAP18/LL-37 (CAMP) was not affected by TLR agonists, but was found to be up-regulated by both 1, 25 hydroxyvitamin D3 and 25 hydroxyvitamin D3. However, no association was found between serum levels of vitamin D and hCAP18/LL-37 concentrations in cervicovaginal secretions (n = 116). Exposure to synthetic LL-37 had a pro-inflammatory effect on endocervical epithelial cell lines, increasing secretion of inflammatory cytokine IL-8. Together these data demonstrate inducible expression of hCAP18/LL-37 in the female lower reproductive tract in vivo and suggest the capacity for this peptide to modulate host defence to infection in this system. Further investigation will elucidate the effects of hCAP18/LL-37 on the physiology and pathophysiology of labour, and may lead to strategies for the prevention of infection-associated preterm birth.


Assuntos
Peptídeos Catiônicos Antimicrobianos/biossíntese , Colo do Útero/metabolismo , Adulto , Peptídeos Catiônicos Antimicrobianos/antagonistas & inibidores , Calcifediol/farmacologia , Linhagem Celular , Colo do Útero/efeitos dos fármacos , Estudos de Coortes , Citocinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Humanos , Interleucina-8/metabolismo , Gravidez , Receptores Toll-Like/agonistas , Receptores Toll-Like/metabolismo , Vaginose Bacteriana/metabolismo , Vitamina D/sangue , Vitamina D/farmacologia , Catelicidinas
17.
J Neurosurg Pediatr ; 14(2): 149-54, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24905842

RESUMO

Intracranial infantile hemangiopericytomas (HPCs) are exceedingly rare lesions. Only 11 cases have been previously reported in the literature. As such, little is known about the etiology, long-term prognosis, and optimal treatment paradigm. Clinically, they are consistently less aggressive than those in adults. The authors present the case of a 2-month-old boy with an intracranial HPC, review the available literature, discuss the evolving concepts of what defines an HPC, and offer a potential explanation to how HPC histology might relate to the clinical behavior of these lesions.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Encéfalo/patologia , Hemangiopericitoma/diagnóstico , Hemangiopericitoma/terapia , Neoplasias Encefálicas/patologia , Hemangiopericitoma/patologia , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Prognóstico
18.
Ochsner J ; 14(1): 14-22, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24688328

RESUMO

BACKGROUND: In the United States, expenditures related to spine care are estimated to account for $86 billion annually. Policy makers have set a cost-effectiveness benchmark of less than $100,000/quality adjusted life year (QALY), forcing surgeons to defend their choices economically. This study projects the cost/QALY for surgical treatment of adult spinal deformity at 5-year follow-up based on 2-year cost- and health-related quality-of-life (HRQOL) data. METHODS: In a review of 541 patients with adult spinal deformity, the patients who underwent revision or were likely to undergo revision were identified and cost of surgery was doubled to account for the second procedure; all other patients maintained the cost of the initial surgery. Oswestry Disability Index (ODI) was modeled by revision status based on literature findings. Total surgical cost was based on Medicare reimbursement. Chi square and student t tests were utilized to compare cost-effective and non-cost-effective patients. RESULTS: The average cost/QALY at 5-year follow-up was $120,311.73. A total of 40.7% of patients fell under the threshold of a cost/QALY <$100,000. Cost-effective patients had higher baseline ODI scores (45% vs 34% [P=0.001]), lower baseline total Scoliosis Research Society scores (2.89 vs 3.00 [P=0.04]), and shorter fusions (8.23 vs 9.87 [P=0.0001]). CONCLUSION: We found 40.7% of patients to be below the threshold of cost effectiveness. Factors associated with reaching the threshold <$100,000/QALY were greater preoperative disability, diagnosis of idiopathic scoliosis, poor preoperative HRQOL scores, and fewer fusion levels.

19.
PLoS One ; 8(8): e73659, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24023689

RESUMO

Respiratory syncytial virus is a leading cause of lower respiratory tract illness among infants, the elderly and immunocompromised individuals. Currently, there is no effective vaccine or disease modifying treatment available and novel interventions are urgently required. Cathelicidins are cationic host defence peptides expressed in the inflamed lung, with key roles in innate host defence against infection. We demonstrate that the human cathelicidin LL-37 has effective antiviral activity against RSV in vitro, retained by a truncated central peptide fragment. LL-37 prevented virus-induced cell death in epithelial cultures, significantly inhibited the production of new infectious particles and diminished the spread of infection, with antiviral effects directed both against the viral particles and the epithelial cells. LL-37 may represent an important targetable component of innate host defence against RSV infection. Prophylactic modulation of LL-37 expression and/or use of synthetic analogues post-infection may represent future novel strategies against RSV infection.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Antivirais/farmacologia , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Vírus Sinciciais Respiratórios/fisiologia , Sequência de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Antivirais/química , Antivirais/uso terapêutico , Morte Celular/efeitos dos fármacos , Linhagem Celular , Citoproteção/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Células Epiteliais/virologia , Humanos , Interferon Tipo I/biossíntese , Dados de Sequência Molecular , Fragmentos de Peptídeos/farmacologia , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico , Infecções por Vírus Respiratório Sincicial/virologia , Vírion/efeitos dos fármacos , Vírion/metabolismo , Catelicidinas
20.
Spine J ; 13(6): 651-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23353002

RESUMO

BACKGROUND CONTEXT: Although lumbar interbody fusion has long been a common procedure in the practice of spine surgery, focus on the technological development has produced the relatively new procedure of transforaminal lumbar interbody fusion (TLIF). This procedure is often available to surgeons as an alternative to anterior-posterior circumferential fusion (AP fusion), and both procedures have been demonstrated to be clinically equivalent at up to 5 years after surgery. In the context of clinical equipoise, it is unknown which procedure is more economically advantageous. PURPOSE: To compare the hospital costs, charges, and payments received for surgical treatment with either AP fusion or TLIF. Future directions for health economic research with respect to spine surgery are also considered and discussed. STUDY DESIGN: This is an institutional review board-approved, single-institution retrospective chart review and cost analysis. PATIENT SAMPLE: Our study included patients undergoing either single-level AP fusion or single-level TLIF between 2006 and 2008. All patients were older than 18 years at the time of surgery; the decision of which procedure was performed was entirely at the discretion of the attending surgeon. OUTCOME MEASURES: Hospital costs, charges, and payments received for the treatment of each patient. METHODS: We performed a retrospective review of the medical and financial records of patients undergoing either AP fusion (n=179) or TLIF (n=90) on one operative level between 2006 and 2008. Medical records were evaluated for a history of spine surgery, operative time, estimated blood loss, and length of stay, whereas financial records were reviewed for the hospital costs, charges, and payments received as recorded by the hospital accounting data. Operative materials and service charges were also isolated and compared separately. This study was departmentally sponsored; there were no interest-associated biases for any of the authors involved. RESULTS: AP fusion patients had a longer operative time than TLIF patients, with a mean time of 246.5 versus 202.7 minutes (p<.01). Conversely, TLIF patients had a higher estimated blood loss during surgery (469.8 cm(3)) than AP fusion patients (311.2 cm(3)) (p<.01). The mean hospital cost for AP fusion was $25,165, whereas for TLIF was $23,390 (p=.04). The mean hospital charges and payments received for AP fusion were 1.07 (p=.05) and 1.35 (p<.01) times those received for TLIF, respectively. Therefore, mean hospital charges and payments received for TLIF were 0.93 and 0.76 times those received for AP fusion, respectively. CONCLUSIONS: Our study demonstrates that a single-level AP fusion results in longer operative time, lower blood loss during surgery, higher hospital costs, higher hospital charges, and greater payments received than a single-level TLIF. Although the decision on how best to treat a patient lies solely at the judgment of the attending surgeon, this comparative cost information may be pertinent in cases of clinical equivalence. This study also calls attention to various shortcomings that are found in present spine surgery cost-effectiveness research, as there is an ongoing need for increased standards of quality in the area of health economics research.


Assuntos
Fusão Vertebral/economia , Fusão Vertebral/métodos , Adulto , Custos e Análise de Custo , Feminino , Humanos , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo
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