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1.
Front Immunol ; 14: 1253626, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37928521

RESUMO

Influenza A viruses (IAVs) pose a significant threat to both human and animal health. Developing IAV vaccine strategies able to elicit broad heterologous protection against antigenically diverse IAV strains is pivotal in effectively controlling the disease. The goal of this study was to examine the immunogenicity and protective efficacy of diverse H1N1 influenza vaccine strategies including monovalent, bivalent, and heterologous prime-boost vaccination regimens, against a mismatched H1N2 swine influenza virus. Five groups were homologous prime-boost vaccinated with either an oil-adjuvanted whole-inactivated virus (WIV) monovalent A/swine/Georgia/27480/2019 (GA19) H1N2 vaccine, a WIV monovalent A/sw/Minnesota/A02636116/2021 (MN21) H1N1 vaccine, a WIV monovalent A/California/07/2009 (CA09) H1N1, a WIV bivalent vaccine composed of CA09 and MN21, or adjuvant only (mock-vaccinated group). A sixth group was prime-vaccinated with CA09 WIV and boosted with MN21 WIV (heterologous prime-boost group). Four weeks post-boost pigs were intranasally and intratracheally challenged with A/swine/Georgia/27480/2019, an H1N2 swine IAV field isolate. Vaccine-induced protection was evaluated based on five critical parameters: (i) hemagglutination inhibiting (HAI) antibody responses, (ii) clinical scores, (iii) virus titers in nasal swabs and respiratory tissue homogenates, (iv) BALf cytology, and (v) pulmonary pathology. While all vaccination regimens induced seroprotective titers against homologous viruses, heterologous prime-boost vaccination failed to enhance HAI responses against the homologous vaccine strains compared to monovalent vaccine regimens and did not expand the scope of cross-reactive antibody responses against antigenically distinct swine and human IAVs. Mismatched vaccination regimens not only failed to confer clinical and virological protection post-challenge but also exacerbated disease and pathology. In particular, heterologous-boosted pigs showed prolonged clinical disease and increased pulmonary pathology compared to mock-vaccinated pigs. Our results demonstrated that H1-specific heterologous prime-boost vaccination, rather than enhancing cross-protection, worsened the clinical outcome and pathology after challenge with the antigenically distant A/swine/Georgia/27480/2019 strain.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Humanos , Animais , Suínos , Vírus da Influenza A Subtipo H1N2 , Anticorpos Antivirais , Vacinação , Adjuvantes Imunológicos
2.
Heredity (Edinb) ; 131(5-6): 361-373, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37813941

RESUMO

Examining the frequency and distribution of hybrids across contact zones provide insights into the factors mediating hybridization. In this study, we examined the effect of habitat and climate on hybridization patterns for three phenotypically, genetically, and ecologically distinct groups of the Canada jay (Perisoreus canadensis) in a secondary contact zone in western North America. Additionally, we tested whether the frequency of hybridization involving the three groups (referred to as Boreal, Pacific and Rocky Mountain morphotypes) is similar across the hybrid zones or whether some pairs have hybridized more frequently than others. We reanalyzed microsatellite, mtDNA and plumage data, and new microsatellite and plumage data for 526 individuals to identify putative genetic and phenotypic hybrids. The genetically and phenotypically distinct groups are associated with different habitats and occupy distinct climate niches across the contact zone. Most putative genetic hybrids (86%) had Rocky Mountain ancestry. Hybrids were observed most commonly in intermediate climate niches and in habitats where Engelmann spruce (Picea engelmannii) overlaps broadly with boreal and subalpine tree species. Our finding that hybrids occupy intermediate climate niches relative to parental morphotypes matches patterns for other plant and animal species found in this region. This study demonstrates how habitat and climate influence hybridization patterns in areas of secondary contact and adds to the growing body of research on tri-species hybrid zones.


Assuntos
Picea , Aves Canoras , Animais , Ecossistema , Clima , Hibridização Genética , Picea/genética , Canadá
3.
Plant Dis ; 105(11): 3545-3553, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34142850

RESUMO

Apple scab is one of the most economically important diseases of apple in temperate production regions. In the absence of durable host resistance in commercially preferred cultivars, considerable applications of fungicides are needed to manage this disease. With the sequential development of resistance to nearly all classes of single-site fungicides in the apple scab pathogen Venturia inaequalis, synthetic multisite fungicides, such as mancozeb and captan, often comprise the core of chemical management programs for apple scab. Although these fungicides have demonstrable benefits for both disease and fungicide resistance management, the sustainability movement within agriculture aims to reduce reliance on such fungicides because of their broader environmental impacts. In this study, we establish a framework to enhance the feasibility of chemical management programs that do not rely on use of synthetic multisite protectant fungicides to manage apple scab. Specifically, we wish to evaluate chemical programs that integrate the biopesticide Bacillus subtilis QST 713 (Serenade Opti) in rotation with benzovindiflupyr (Aprovia), a single-site fungicide belonging to the class of succinate dehydrogenase inhibitors (SDHI), to circumvent the need for applications of synthetic multisite fungicides. During implementation of these programs, disease incidence data were taken at biweekly intervals. Regardless of the seasonal challenges presented in the 2 years of this study, when Bacillus subtilis QST 713 was used in place of captan and mancozeb mixtures, we did not observe any significant differences (P > 0.05) in development of apple scab symptoms between any of the management programs for the vertical axis or super spindle orchards in either year. This potential for substituting synthetic multisite fungicides with biopesticides is best realized when the programs are used with a decision support system in a super spindle planting system, where trees have reduced canopy densities. This 2-year study shows the potential to achieve adequate disease control using the integration of SDHI fungicides and biological controls without the use of synthetic multisite fungicides.


Assuntos
Ascomicetos , Fungicidas Industriais , Malus , Bacillus subtilis , Agentes de Controle Biológico , Captana , Fungicidas Industriais/farmacologia , Maneb , Norbornanos , Doenças das Plantas , Pirazóis , Zineb
4.
Science ; 358(6366): 1033-1037, 2017 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-29170231

RESUMO

When deformed beyond their elastic limits, crystalline solids flow plastically via particle rearrangements localized around structural defects. Disordered solids also flow, but without obvious structural defects. We link structure to plasticity in disordered solids via a microscopic structural quantity, "softness," designed by machine learning to be maximally predictive of rearrangements. Experimental results and computations enabled us to measure the spatial correlations and strain response of softness, as well as two measures of plasticity: the size of rearrangements and the yield strain. All four quantities maintained remarkable commonality in their values for disordered packings of objects ranging from atoms to grains, spanning seven orders of magnitude in diameter and 13 orders of magnitude in elastic modulus. These commonalities link the spatial correlations and strain response of softness to rearrangement size and yield strain, respectively.

6.
Mucosal Immunol ; 10(3): 789-801, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27759021

RESUMO

Infection-associated inflammatory stress during pregnancy is the most common cause of fetal growth restriction and/or miscarriage. Treatment strategies for protection of at-risk mothers are limited to a narrow range of vaccines, which do not cover the bulk of the common pathogens most frequently encountered. Using mouse models, we demonstrate that oral treatment during pregnancy with a microbial-derived immunomodulator (OM85), currently used clinically for attenuation of infection-associated airway inflammatory symptoms in infants-adults, markedly reduces risk for fetal loss/growth restriction resulting from maternal challenge with bacterial lipopolysaccharide or influenza. Focusing on LPS exposure, we demonstrate that the key molecular indices of maternal inflammatory stress, notably high levels of RANTES, MIP-1α, CCL2, KC, and G-CSF (granulocyte colony-stimulating factor) in gestational tissues/serum, are abrogated by OM85 pretreatment. Systems-level analyses conducted in parallel using RNASeq revealed that OM85 pretreatment selectively tunes LPS-induced activation in maternal gestational tissues for attenuated expression of TNF, IL1, and IFNG-driven proinflammatory networks, without constraining Type1-IFN-associated networks central to first-line antimicrobial defense. This study suggests that broad-spectrum protection-of-pregnancy against infection-associated inflammatory stress, without compromising capacity for efficient pathogen eradication, represents an achievable therapeutic goal.


Assuntos
Aborto Espontâneo/imunologia , Antígenos de Bactérias/imunologia , Infecções Bacterianas/imunologia , Fatores Imunológicos/imunologia , Vírus da Influenza A/imunologia , Infecções por Orthomyxoviridae/imunologia , Efeitos Tardios da Exposição Pré-Natal/imunologia , Aborto Espontâneo/etiologia , Aborto Espontâneo/prevenção & controle , Animais , Infecções Bacterianas/complicações , Modelos Animais de Doenças , Regulação para Baixo , Feminino , Desenvolvimento Fetal , Humanos , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/complicações , Gravidez , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Estudo de Prova de Conceito
7.
Clin Exp Immunol ; 187(3): 408-417, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27859014

RESUMO

In areas where Streptococcus pneumoniae is highly endemic, infants experience very early pneumococcal colonization of the upper respiratory tract, with carriage often persisting into adulthood. We aimed to explore whether newborns in high-risk areas have pre-existing pneumococcal-specific cellular immune responses that may affect early pneumococcal acquisition. Cord blood mononuclear cells (CBMC) of 84 Papua New Guinean (PNG; high endemic) and 33 Australian (AUS; low endemic) newborns were stimulated in vitro with detoxified pneumolysin (dPly) or pneumococcal surface protein A (PspA; families 1 and 2) and compared for cytokine responses. Within the PNG cohort, associations between CBMC dPly and PspA-induced responses and pneumococcal colonization within the first month of life were studied. Significantly higher PspA-specific interferon (IFN)-γ, tumour necrosis factor (TNF)-α, interleukin (IL)-5, IL-6, IL-10 and IL-13 responses, and lower dPly-IL-6 responses were produced in CBMC cultures of PNG compared to AUS newborns. Higher CBMC PspA-IL-5 and PspA-IL-13 responses correlated with a higher proportion of cord CD4 T cells, and higher dPly-IL-6 responses with a higher frequency of cord antigen-presenting cells. In the PNG cohort, higher PspA-specific IL-5 and IL-6 CBMC responses were associated independently and significantly with increased risk of earlier pneumococcal colonization, while a significant protective effect was found for higher PspA-IL-10 CBMC responses. Pneumococcus-specific cellular immune responses differ between children born in pneumococcal high versus low endemic settings, which may contribute to the higher risk of infants in high endemic settings for early pneumococcal colonization, and hence disease.


Assuntos
Sangue Fetal/imunologia , Sangue Fetal/microbiologia , Imunidade Celular/imunologia , Infecções Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Anticorpos Antibacterianos/imunologia , Células Apresentadoras de Antígenos/imunologia , Antígenos de Bactérias/imunologia , Austrália , Proteínas de Bactérias/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/microbiologia , Células Cultivadas , Citocinas/imunologia , Feminino , Humanos , Recém-Nascido , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/microbiologia , Papua Nova Guiné , Infecções Pneumocócicas/microbiologia , Gravidez , Risco
8.
Opt Lett ; 41(7): 1423-6, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27192252

RESUMO

The propagation characteristics of a spatial Gaussian laser pulse have been studied inside a gradient-index structured crystalline lens with constant-density plasma generated by the laser-tissue interaction. The propagation of the laser pulse is affected by the nonlinearities introduced by the generated plasma inside the crystalline lens. Owing to the movement of plasma species from a higher- to a lower-temperature region, an increase in the refractive index occurs that causes the focusing of the laser pulse. In this study, extended paraxial approximation has been applied to take into account the evolution of the radial profile of the Gaussian laser pulse. To examine the propagation characteristics, variation of the beam width parameter has been observed as a function of the laser power and initial beam radius. The cavitation bubble formation, which plays an important role in the restoration of the elasticity of the crystalline lens, has been investigated.


Assuntos
Cristalino/química , Elasticidade , Humanos , Lasers
9.
Opt Lett ; 39(24): 6775-8, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25502994

RESUMO

This Letter presents a model for propagation of a laser pulse in a human crystalline lens. The model contains a transverse beam diffraction effect, laser-induced optical breakdown for the creation of plasma via a multiphoton ionization process, and the gradient index (GRIN) structure. Plasma introduces the nonlinearity in the crystalline lens which affects the propagation of the beam. The multiphoton ionization process generates plasma that changes the refractive index and hence leads to the defocusing of the laser beam. The Letter also points out the relevance of the present investigation to cavitation bubble formation for restoring the elasticity of the eyes.


Assuntos
Cristalino/efeitos da radiação , Fótons , Humanos , Lasers , Fenômenos Ópticos
10.
J Thromb Haemost ; 12(10): 1706-16, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25041188

RESUMO

BACKGROUND: The resolution of deep vein thrombosis requires an inflammatory response and mobilization of proteases, such as urokinase-type plasminogen activator (uPA) and matrix metalloproteinases (MMPs), to degrade the thrombus and remodel the injured vein wall. Plasminogen activator inhibitor type 2 (PAI-2) is a serine protease inhibitor (serpin) with unique immunosuppressive and cell survival properties that was originally identified as an inhibitor of uPA. OBJECTIVE: To investigate the role of PAI-2 in venous thrombus formation and resolution. METHODS: Venous thrombus resolution was compared in wild-type C57BL/6, PAI-2(-/-) , and PAI-1(-/-) mice using the stasis model of deep vein thrombosis. Formed thrombi were harvested, thrombus weights were recorded, and tissue was analyzed for uPA and MMP activities, PAI-1 expression, and the nature of inflammatory cell infiltration. RESULTS: We found that the absence of PAI-2 enhanced venous thrombus resolution, while thrombus formation was unaffected. Enhanced venous thrombus resolution in PAI-2(-/-) mice was associated with increased uPA activity and reduced levels of PAI-1, with no significant effect on MMP-2 and -9 activities. PAI-1 deficiency resulted in an increase in thrombus resolution similar to PAI-2 deficiency, but additionally reduced venous thrombus formation and altered MMP activity. PAI-2-deficient thrombi had increased levels of the neutrophil chemoattractant CXCL2, which was associated with early enhanced neutrophil recruitment. CONCLUSIONS: These data identify PAI-2 as a novel regulator of venous thrombus resolution, which modulates several pathways involving both inflammatory and uPA activity mechanisms, distinct from PAI-1. Further examination of these pathways may lead to potential therapeutic prospects in accelerating thrombus resolution.


Assuntos
Inibidor 2 de Ativador de Plasminogênio/genética , Trombose Venosa/genética , Animais , Cruzamentos Genéticos , Imuno-Histoquímica , Inflamação , Macrófagos/citologia , Macrófagos/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neutrófilos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidor 2 de Ativador de Plasminogênio/fisiologia , Trombose/metabolismo , Trombose Venosa/terapia
11.
J Perinatol ; 34(6): 435-40, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24651735

RESUMO

OBJECTIVE: To examine whether inflammatory bowel disease (IBD) is associated with ischemic/inflammatory conditions during pregnancy. STUDY DESIGN: A retrospective cohort study using the 2000 to 2012 Kaiser Permanente Southern California maternally-linked medical records (n=395 781). The two major subtypes of IBD, ulcerative colitis and Crohn's diseases were studied. Adjusted odds ratios (ORs) were used to quantify the associations. RESULT: A pregnancy complicated by IBD was associated with increased incidence of small-for-gestational age birth (OR=1.46, 95% confidence interval (CI)=1.14 to 1.88), spontaneous preterm birth (OR=1.32, 95% CI=1.00 to 1.76) and preterm premature rupture of membranes (OR=1.95, 95% CI=1.26 to 3.02). Further stratifying by IBD subtypes, only ulcerative colitis was significantly associated with increased incidence of ischemic placental disease, spontaneous preterm birth and preterm premature rupture of membranes. CONCLUSION: The findings underscore the potential impact of maternal IBD on adverse perinatal outcomes. Clinicians should be aware that the association between IBD and adverse perinatal outcome varies by IBD subtypes.


Assuntos
Colite Ulcerativa/complicações , Doença de Crohn/complicações , Complicações na Gravidez , Resultado da Gravidez , Adulto , California/epidemiologia , Estudos de Coortes , Feminino , Ruptura Prematura de Membranas Fetais/etiologia , Humanos , Incidência , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Mães , Gravidez , Nascimento Prematuro/etiologia , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
12.
Mucosal Immunol ; 5(3): 332-41, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22354321

RESUMO

A hallmark of atopic asthma is development of chronic airways hyper-responsiveness (AHR) that persists in the face of ongoing exposure to perennial aeroallergens. We investigated underlying mechanisms in sensitized rats focusing on a strain expressing the high-allergen-responder phenotype characteristic of human atopic asthmatics, and find that their high susceptibility to aeroallergen-induced persistent AHR is associated with deficiencies in the immunoregulatory and mucosal trafficking properties of inducible T-regulatory cells (iTregs). Counterintuitively, AHR susceptibility was inversely related to aeroallergen exposure level, high exposures conferring protection. We demonstrate that underlying this AHR-susceptible phenotype is reduced capacity of airway mucosal dendritic cells (AMDCs) for allergen sampling in vivo; this defect is microenvironmentally acquired, as allergen uptake by these cells in vitro is normal. Moreover, intranasal transfer of in vitro aeroallergen-loaded AMDC from naïve animals into AHR-susceptible animals during prolonged aerosol challenge markedly boosts subsequent accumulation of iTregs in the airway mucosa and rapidly resolves their chronic AHR, suggesting that compromised antigen surveillance by AMDC resulting in defective functional programming of iTreg may be causally related to AHR susceptibility.


Assuntos
Alérgenos/imunologia , Asma/imunologia , Asma/fisiopatologia , Hiper-Reatividade Brônquica/imunologia , Vigilância Imunológica , Mucosa Respiratória/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Transferência Adotiva , Animais , Apresentação de Antígeno , Células Cultivadas , Células Dendríticas/imunologia , Modelos Animais de Doenças , Suscetibilidade a Doenças , Humanos , Imunomodulação , Ovalbumina/imunologia , Ratos , Ratos Endogâmicos BN
13.
J Thromb Haemost ; 9(9): 1847-55, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21752185

RESUMO

BACKGROUND: The interaction of the fibrin ßN-domain with VE-cadherin on endothelial cells is implicated in transendothelial migration of leukocytes, and the ß15-42 fragment representing part of this domain has been shown to inhibit this process. However, our previous study revealed that only a dimeric (ß15-66)(2) fragment, corresponding to the full-length ßN-domain and mimicking its dimeric arrangement in fibrin, bound to VE-cadherin. OBJECTIVE: To test our hypothesis that dimerization of ß15-42-containing fragments increases their affinity for VE-cadherin and ability to inhibit transendothelial migration of leukocytes. METHODS: Interaction of ß15-42-containing fragments with VE-cadherin was characterized by ELISA and surface plasmon resonance. The inhibitory effect of such fragments was tested in vitro with a leukocyte transendothelial migration assay and in vivo with mouse models of peritonitis and myocardial ischemia-reperfusion injury. RESULTS: First, we prepared the monomeric ß15-42 and ß15-64 fragments and their dimeric forms, (ß15-44)(2) and (ß15-66)(2) , and studied their interaction with the fibrin-binding domain of VE-cadherin, VE-cad(3). The experiments revealed that both dimeric fragments bound to VE-cad(3) with high affinity, whereas the affinities of ß15-42 and ß15-64 were significantly lower. Next, we tested the ability of these fragments to inhibit leukocyte transmigration in vitro and infiltration into the inflamed peritoneum in vivo, and found that the inhibitory effects of the dimers on these processes were also superior. Furthermore, (ß15-44)(2) significantly reduced myocardial injury induced by ischemia-reperfusion. CONCLUSION: The results confirm our hypotheses and indicate that (ß15-66)(2) and (ß15-44)(2) , which exhibited much higher affinity for VE-cadherin, are highly effective in suppressing inflammation by inhibiting leukocyte transmigration.


Assuntos
Antígenos CD/metabolismo , Caderinas/metabolismo , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Produtos de Degradação da Fibrina e do Fibrinogênio/farmacologia , Fibrina/metabolismo , Inflamação/metabolismo , Inflamação/prevenção & controle , Animais , Cardiotônicos/farmacologia , Movimento Celular , Dimerização , Células Endoteliais/metabolismo , Produtos de Degradação da Fibrina e do Fibrinogênio/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Técnicas In Vitro , Leucócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Peritonite/prevenção & controle , Domínios e Motivos de Interação entre Proteínas
14.
Opt Lett ; 36(7): 1080-2, 2011 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-21478989

RESUMO

We have demonstrated the generation of 400 µW of power at ~18 µm by difference-frequency mixing the 1038 and 1105 nm from a two-color, chirped pulse amplification Yb fiber system. A two-color seed is selected from a continuum source and amplified to 300 mW of total power in a two-stage Yb fiber amplifier.

15.
Mucosal Immunol ; 4(1): 43-52, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20668438

RESUMO

The hallmark of atopic asthma is transient airways hyperresponsiveness (AHR) preceded by aeroallergen-induced Th-cell activation. This is preceded by upregulation of CD86 on resident airway dendritic cells (DCs) that normally lack competence in T-cell triggering. Moreover, AHR duration is controlled via T-regulatory (Treg) cells, which can attenuate CD86 upregulation on DC. We show that airway mucosal Treg/DC interaction represents an accessible therapeutic target for asthma control. Notably, baseline airway Treg activity in sensitized rats can be boosted by microbe-derived stimulation of the gut, resulting in enhanced capacity to control CD86 expression on airway DC triggered by aeroallergen and accelerated resolution of AHR.


Assuntos
Asma/imunologia , Asma/terapia , Bactérias/imunologia , Extratos Celulares/imunologia , Trato Gastrointestinal/imunologia , Sistema Respiratório/imunologia , Linfócitos T Reguladores/imunologia , Animais , Asma/microbiologia , Antígeno B7-2/genética , Bactérias/citologia , Bactérias/metabolismo , Hiper-Reatividade Brônquica/imunologia , Hiper-Reatividade Brônquica/terapia , Linfócitos T CD4-Positivos/imunologia , Extratos Celulares/uso terapêutico , Citocinas/imunologia , Células Dendríticas/imunologia , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/metabolismo , Trato Gastrointestinal/microbiologia , Subunidade alfa de Receptor de Interleucina-2/imunologia , Ratos , Linfócitos T Auxiliares-Indutores/imunologia
16.
Clin Exp Allergy ; 40(5): 772-85, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20214669

RESUMO

BACKGROUND: In human asthma, and experimental allergic airways disease in mice, antigen-presenting cells and CD4(+) effector cells at the airway mucosa orchestrate, and CD4(+)CD25(+) regulatory T cells attenuate, allergen immunity. UV irradiation of skin before sensitization with ovalbumin (OVA) causes significantly reduced asthma-like responses in respiratory tissues. OBJECTIVE: To determine whether UV-induced changes in CD11c(+) cells, CD4(+)CD25(+) effector cells or CD4(+)CD25(+) regulatory cells in the trachea and airway draining lymph nodes (ADLNs) were responsible for reduced allergic airways disease. METHODS: The phenotype and function of CD11c(+) cells and CD4(+)CD25(+) cells in the trachea and ADLNs of UV- and non-irradiated, OVA-sensitized mice was examined 24 h after a single exposure to aerosolized OVA. RESULTS: No changes in the function of CD11c(+) cells from UV-irradiated mice were observed. CD4(+)CD25(+) cells from UV-irradiated, OVA-sensitized mice harvested 24 h after OVA aerosol proliferated less in response to OVA in vitro and were unable to suppress the proliferation of OVA-sensitized responder cells. This result suggested reduced activation of effector T cells in the airway mucosa of UV-irradiated, OVA-sensitized mice. To exclude regulatory cells of any type, there was similar proliferation in vivo to aerosolized OVA by CFSE-loaded, OVA-TCR-specific CD4(+) cells adoptively transferred into UV- and non-irradiated, OVA-sensitized mice. In addition, there was no difference in the expression of regulatory T cell markers (Foxp3, IL-10, TGF-beta mRNA). To examine effector T cells, ADLN cells from UV-irradiated, OVA-sensitized and -challenged mice were cultured with OVA. There was reduced expression of the early activation marker CD69 by CD4(+)CD25(+) cells, and reduced proliferation in the absence of the regulatory cytokine, IL-10. CONCLUSION: Reduced allergic airways disease in UV-irradiated mice is due to fewer effector CD4(+)CD25(+) cells in the trachea and ADLNs, and not due to UV-induced regulatory cells.


Assuntos
Asma/imunologia , Pele/efeitos da radiação , Linfócitos T Reguladores/efeitos da radiação , Raios Ultravioleta , Alérgenos/administração & dosagem , Alérgenos/imunologia , Animais , Antígenos CD/biossíntese , Antígenos de Diferenciação de Linfócitos T/biossíntese , Antígeno CD11c/metabolismo , Proliferação de Células , Células Cultivadas , Regulação para Baixo , Feminino , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Lectinas Tipo C/biossíntese , Linfonodos/efeitos da radiação , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Pele/imunologia , Linfócitos T Reguladores/imunologia , Traqueia/imunologia , Traqueia/efeitos da radiação
17.
Neuroscience ; 158(4): 1460-8, 2009 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-19047013

RESUMO

In this study, we examined protein-protein interactions between two neuronal receptors, low density lipoprotein receptor-related protein (LRP) and sorLA/LR11, and found that these receptors interact, as indicated by three independent lines of evidence: co-immunoprecipitation experiments on mouse brain extracts and mouse neuronal cells, surface plasmon resonance analysis with purified human LRP and sorLA, and fluorescence lifetime imaging microscopy (FLIM) on rat primary cortical neurons. Immunocytochemistry experiments revealed widespread co-localization of LRP and sorLA within perinuclear compartments of rat primary neurons, while FLIM analysis showed that LRP-sorLA interactions take place within a subset of these compartments.


Assuntos
Proteínas Relacionadas a Receptor de LDL/metabolismo , Receptores de LDL/metabolismo , Animais , Sítios de Ligação , Células Cultivadas , Embrião de Mamíferos , Proteínas de Fluorescência Verde/genética , Humanos , Imunoprecipitação/métodos , Proteínas Relacionadas a Receptor de LDL/genética , Camundongos , Microscopia de Fluorescência , Neuroblastoma , Neurônios/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Mapeamento de Interação de Proteínas/métodos , Ratos , Ratos Sprague-Dawley , Receptores de LDL/genética , Ressonância de Plasmônio de Superfície/métodos , Transfecção/métodos
18.
Chem Immunol Allergy ; 94: 40-47, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18802335

RESUMO

Interest in regulatory T cells (Treg) and their role in immune regulation has grown almost exponentially over the last 10 years, though the notion of a suppressive population of T cells has been in existence since the early 1970s. Recent reports have highlighted the potential role of populations of Treg in control of T-cell-mediated inflammation in tissues, including the lung. In particular, there is now evidence to suggest that Treg form a fundamental part of the regulatory axis operating within the respiratory mucosa and that the number of Treg recruited to the airways may be crucial for the inhibition of airways hyperresponsiveness associated with exacerbations of asthma. A discussion of these concepts is the focus of this chapter.


Assuntos
Citocinas/metabolismo , Imunidade nas Mucosas , Hipersensibilidade Respiratória/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Animais , Citocinas/imunologia , Dessensibilização Imunológica , Retroalimentação Fisiológica , Glucocorticoides/imunologia , Glucocorticoides/uso terapêutico , Humanos , Tolerância Imunológica , Pneumonia , Hipersensibilidade Respiratória/patologia , Hipersensibilidade Respiratória/terapia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia
19.
Opt Lett ; 33(10): 1065-7, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18483513

RESUMO

A short-pulse, two-color Yb:fiber laser system has been developed for mid-infrared generation. To date, 20 microW of average power at a wavelength of approximately 18 microm is generated by difference-frequency mixing 300 mW average power from the two-color Yb:fiber amplifier. The mid-infrared power was not limited by two-photon absorption, allowing it to be scaled by increasing the amplifier power.

20.
J Thromb Haemost ; 6(4): 638-44, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18194421

RESUMO

BACKGROUND: Factor V is endocytosed by megakaryocytes from plasma via a specific, receptor-mediated, clathrin-dependent mechanism to form the unique platelet-derived FV pool. OBJECTIVE: The role of low-density lipoprotein (LDL) receptor-related protein-1 (LRP-1), or a related family member, in FV endocytosis by megakaryocytes was examined because of its known interactions with other proteins involved in hemostasis. METHODS: LRP-1 expression by megakaryocytes and its functional role in FV endocytosis was confirmed using reverse transcription polymerase chain reaction (RT-PCR) and specific antibodies. FV binding to megakaryocytes was performed under Ca(2+)-free conditions to quantify binding in the absence of endocytosis. RESULTS AND CONCLUSION: Cell surface expression of LRP-1 by CD34+ ex vivo-derived megakaryocytes and the megakaryocyte-like cell line CMK was confirmed using anti-LRP-1 antibodies and was consistent with the detection of LRP-1 message in these cells. All cells capable of endocytosing FV expressed LRP-1. Anti-LRP-1 antibodies and receptor-associated protein (RAP), a known antagonist of LDL receptor family members, displaced only 50% of the [(125)I]FV bound to megakaryocytes. FV binding to megakaryocytes showed positive cooperativity (Hill coefficient = 1.92 +/- 0.18) that was substantially reduced in the presence of RAP (1.47 +/- 0.26). As FV endocytosis is specific to this cofactor, a model is hypothesized where FV binding to a specific receptor facilitates binding and endocytosis of a second FV molecule by LRP-1, or a related family member. These combined observations describe a unique role for LRP-1 in endocytosis of a coagulation protein trafficked to alpha-granules and not destined for lysosomal degradation.


Assuntos
Endocitose/fisiologia , Fator V/metabolismo , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/fisiologia , Megacariócitos/metabolismo , Cálcio/farmacologia , Linhagem Celular/metabolismo , AMP Cíclico/análogos & derivados , AMP Cíclico/farmacocinética , Fator V/farmacologia , Corantes Fluorescentes/farmacocinética , Humanos , Hidrazinas/farmacocinética , Proteína Associada a Proteínas Relacionadas a Receptor de LDL/farmacologia , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/biossíntese , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Megacariócitos/efeitos dos fármacos , Ligação Proteica , Mapeamento de Interação de Proteínas , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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