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1.
J Clin Invest ; 134(18)2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39286984

RESUMO

T cell-based immunotherapies are a promising therapeutic approach for multiple malignancies, but their efficacy is limited by tumor hypoxia arising from dysfunctional blood vessels. Here, we report that cell-intrinsic properties of a single vascular component, namely the pericyte, contribute to the control of tumor oxygenation, macrophage polarization, vessel inflammation, and T cell infiltration. Switching pericyte phenotype from a synthetic to a differentiated state reverses immune suppression and sensitizes tumors to adoptive T cell therapy, leading to regression of melanoma in mice. In melanoma patients, improved survival is correlated with enhanced pericyte maturity. Importantly, pericyte plasticity is regulated by signaling pathways converging on Rho kinase activity, with pericyte maturity being inducible by selective low-dose therapeutics that suppress pericyte MEK, AKT, or notch signaling. We also show that low-dose targeted anticancer therapy can durably change the tumor microenvironment without inducing adaptive resistance, creating a highly translatable pathway for redosing anticancer targeted therapies in combination with immunotherapy to improve outcome.


Assuntos
Pericitos , Animais , Pericitos/imunologia , Pericitos/metabolismo , Pericitos/patologia , Camundongos , Humanos , Microambiente Tumoral/imunologia , Microambiente Tumoral/efeitos dos fármacos , Imunoterapia , Melanoma Experimental/imunologia , Melanoma Experimental/terapia , Melanoma Experimental/patologia , Fenótipo , Melanoma/imunologia , Melanoma/terapia , Melanoma/patologia , Melanoma/tratamento farmacológico , Linhagem Celular Tumoral , Tolerância Imunológica/efeitos dos fármacos
2.
Oncoimmunology ; 13(1): 2406576, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39314905

RESUMO

Gastrointestinal stromal tumors (GISTs) harbor diverse immune cell populations but so far immunotherapy in patients has been disappointing. Here, we established cord blood humanized mouse models of localized and disseminated GIST to explore the remodeling of the tumor environment for improved immunotherapy. Specifically, we assessed the ability of a cancer vascular targeting peptide (VTP) to bind to mouse and patient GIST angiogenic blood vessels and deliver the TNF superfamily member LIGHT (TNFS14) into tumors. LIGHT-VTP treatment of GIST in humanized mice improved vascular function and tumor oxygenation, which correlated with an overall increase in intratumoral human effector T cells. Concomitant with LIGHT-mediated vascular remodeling, we observed intratumoral high endothelial venules (HEVs) and tertiary lymphoid structures (TLS), which resemble spontaneous TLS found in GIST patients. Thus, by overcoming the limitations of immunodeficient xenograft models, we demonstrate the therapeutic feasibility of vascular targeting and immune priming in human GIST. Since TLS positively correlate with patient prognosis and improved response to immune checkpoint inhibition, vascular LIGHT targeting in GIST is a highly translatable approach to improve immunotherapeutic outcomes.


Assuntos
Tumores do Estroma Gastrointestinal , Estruturas Linfoides Terciárias , Animais , Tumores do Estroma Gastrointestinal/imunologia , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/terapia , Humanos , Camundongos , Estruturas Linfoides Terciárias/imunologia , Estruturas Linfoides Terciárias/patologia , Modelos Animais de Doenças , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Sangue Fetal/citologia , Microambiente Tumoral/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto , Imunoterapia/métodos , Neovascularização Patológica/imunologia , Neovascularização Patológica/patologia , Linhagem Celular Tumoral , Neoplasias Gastrointestinais/imunologia , Neoplasias Gastrointestinais/patologia , Neoplasias Gastrointestinais/terapia
3.
Data Brief ; 54: 110278, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38962193

RESUMO

This Data in Brief (DiB) article presents the differences in cycling behaviors related to violations, errors, and positive behaviors by region. The study data were collected by means of a structured questionnaire applied to a full sample of 7,001 participants from 19 countries, distributed over 5 continents. This paper proposes descriptive statistics, as well as common statistical tests. The aim is to enable authors to make their own analyses, not to provide precise interpretations. For further information about the macro project supporting the collection of these data, it is advised to refer to the paper titled "Cross-culturally approaching the cycling behavior questionnaire (CBQ): Evidence from 19 countries", published in Transportation Research Part F: Traffic Psychology and Behavior.

4.
J Adolesc Health ; 73(2): 383-386, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37140518

RESUMO

PURPOSE: Examine racial discrimination of adolescents of color by type of special healthcare need (SHCN). METHODS: Pooled cross-sectional data of youth over 10 years of age from 2018 to 2020 National Surveys of Children's Health were used (n = 48,220). Rates of discrimination by SHCN diagnoses within racial and ethnic groups were examined. RESULTS: Adolescents of color with SHCNs were almost twice as likely to experience racial discrimination as peers of color without SHCNs. Asian youth with SHCNs were over 3.5 times likely to experience racial discrimination as peers without. Youth with depression experienced highest rates of racial discrimination. Compared to peers without, Black youth with asthma or a genetic disorder, and Hispanic youth with autism or intellectual disabilities, experienced higher rates of racial discrimination. DISCUSSION: SHCN status heightens racial discrimination for adolescents of color. However, this risk was not uniform by racial or ethnic group for every SHCN type.


Assuntos
Asma , Racismo , Criança , Humanos , Adolescente , Estudos Transversais , Hispânico ou Latino , Atenção à Saúde
5.
Front Psychiatry ; 13: 889602, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35664474

RESUMO

Background: Mental illness in transition age youth is common and treatment initiation is often delayed. Youth overwhelmingly report utilizing the Internet to gather information while psychiatric symptoms emerge, however, most are not yet ready to receive a referral to care, forestalling the established benefit of early intervention. Methods: A digital outreach campaign and interactive online care navigation platform was developed and deployed in New York State on October 22, 2020. The campaign offers live connection to a peer or counselor, a self-assessment mental health quiz, and educational material all designed to promote help-seeking in youth and their allies. Results: Between October 22, 2020 and July 31, 2021, the campaign resulted in 581,981 ad impressions, 16,665 (2.9%) clicks, and 13,717 (2.4%) unique website visitors. A third (4,562, 33.2%) completed the quiz and 793 (0.1%) left contact information. Of those, 173 (21.8%) completed a virtual assessment and 155 (19.5%) resulted in a referral to care. The median age of those referred was 21 years (IQR = 11) and 40% were considered to be from low-income areas. Among quiz completers, youth endorsing symptoms of depression or anxiety were more likely to leave contact information (OR = 2.18, 95% CI [1.39, 3.41] and OR = 1.69, 95% CI [1.31, 2.19], respectively) compared to those not reporting symptoms of depression or anxiety. Youth endorsing symptoms of psychosis were less likely to report a desire to receive a referral to care (OR = 0.58, 95% CI [0.43, 0.80]) compared to those who did not endorse symptoms of psychosis. Conclusion: Self-reported symptomatology impact trajectories to care, even at the earliest stages of help-seeking, while youth and their allies are searching for information online. An online care navigation team could serve as an important resource for individuals with emerging behavioral health concerns and help to guide the transition between online information seeking at baseline to care.

6.
Chem Commun (Camb) ; 57(89): 11839-11842, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34698738

RESUMO

Herein, we report a series of di-anionic supramolecular self-associating amphiphiles (SSAs). We elucidate the antimicrobial properties of these SSAs against both methicillin resistant Staphylococcus aureus and Escherichia coli. In addition, we show this class of compound to form both intra- and intermolecular hydrogen bonded macrocyclic structures in the solid state.


Assuntos
Alcanossulfonatos/farmacologia , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Compostos de Fenilureia/farmacologia , Tensoativos/farmacologia , Alcanossulfonatos/química , Antibacterianos/química , Ligação de Hidrogênio , Testes de Sensibilidade Microbiana , Compostos de Fenilureia/química , Espectroscopia de Prótons por Ressonância Magnética , Tensoativos/química
7.
Exp Eye Res ; 212: 108754, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34506802

RESUMO

PURPOSE: To assess age-related changes in the rhesus macaque eye and evaluate them to corresponding human age-related eye disease. METHODS: Data from eye exams and imaging tests including intraocular pressure (IOP), lens thickness, axial length, and retinal optical coherence tomography (OCT) images were evaluated from 142 individuals and statistically analyzed for age-related changes. Quantitative autofluorescence (qAF) was measured as was the presence of macular lesions as related to age. RESULTS: Ages of the 142 rhesus macaques ranged from 0.7 to 29 years (mean = 16.4 years, stdev = 7.5 years). Anterior segment measurements such as IOP, lens thickness, and axial length were acquired. Advanced retinal imaging in the form of optical coherence tomography and qAF were obtained. Quantitative assessments were made and variations by age groups were analyzed to compare with established age-related changes in human eyes. Quantitative analysis of data revealed age-related increase in intraocular pressure (0.165 mm Hg per increase in year of age), ocular biometry (lens thickness 7.2 µm per increase in year of age; and axial length 52.8 µm per increase in year of age), and presence of macular lesions. Age-related changes in thicknesses of retinal layers on OCT were observed and quantified, showing decreased thickness of the retinal ganglion cell layer and inner nuclear layer, and increased thickness of photoreceptor outer segment and choroidal layers. Age was correlated with increased qAF by 1.021 autofluorescence units per increase in year of age. CONCLUSIONS: The rhesus macaque has age-related ocular changes similar to humans. IOP increases with age while retinal ganglion cell layer thickness decreases. Macular lesions develop in some aged animals. Our findings support the concept that rhesus macaques may be useful for the study of important age-related diseases such as glaucoma, macular diseases, and cone disorders, and for development of therapies for these diseases.


Assuntos
Envelhecimento , Oftalmopatias/diagnóstico , Células Ganglionares da Retina/patologia , Tomografia de Coerência Óptica/métodos , Animais , Biometria , Modelos Animais de Doenças , Oftalmopatias/fisiopatologia , Macaca mulatta
8.
Transl Vis Sci Technol ; 10(6): 7, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-34111251

RESUMO

Purpose: To determine the range of normal ocular biometry and perform advanced retinal imaging and functional assessment of the rhesus macaque eye. Methods: We performed ocular phenotyping on rhesus macaques at the California National Primate Research Center. This process consisted of anterior and posterior segment eye examination by ophthalmologists, advanced retinal imaging, and functional retinal electrophysiology. Results: Full eye examinations were performed on 142 animals, consisting of pupillary light reflex, tonometry, external examination and photography, anterior slit lamp examination, and posterior segment examination by indirect ophthalmoscopy. Ages of the rhesus macaques ranged from 0.7 to 29 years (mean, 16.4 ± 7.5 years). Anterior segment measurements such as intraocular pressure (n = 142), corneal thickness (n = 84), lens thickness (n = 114), and axial length (n = 114) were acquired. Advanced retinal imaging in the form of fundus photography (n = 78), optical coherence tomography (n = 60), and quantitative autofluorescence (n = 44) was obtained. Electroretinography (n = 75) was used to assay retinal function. Quantitative analyses of the macular structure, retinal layer segmentation, and rod and cone photoreceptor electrical responses are reported. Quantitative assessments were made and variations between sexes were analyzed to compare with established sex changes in human eyes. Conclusions: The rhesus macaque has an ocular structure and function very similar to that of the human eye. In particular macular structure and retinal function is very similar to humans, making this species particularly useful for the study of macular biology and development of therapies for cone photoreceptor disorders. Translational Relevance: Rhesus macaques are an ideal model for future vision science studies of human eye diseases.


Assuntos
Retina , Tomografia de Coerência Óptica , Animais , Eletrorretinografia , Pressão Intraocular , Macaca mulatta , Retina/diagnóstico por imagem
9.
Invest Ophthalmol Vis Sci ; 61(8): 16, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32663290

RESUMO

Purpose: To employ quantitative fundus autofluorescence (qAF) imaging in rhesus macaques to noninvasively assess retinal pigment epithelial (RPE) lipofuscin in nonhuman primates (NHPs) as a model of aging and age-related macular degeneration (AMD). Methods: The qAF imaging was performed on eyes of 26 rhesus macaques (mean age 18.8 ± 8.2 years, range 4-27 years) with normal-appearing fundus or with age-related soft drusen using a confocal scanning laser ophthalmoscope with 488 nm excitation and an internal fluorescence reference. Eyes with soft drusen also underwent spectral-domain optical coherence tomography imaging to measure drusen volume and height of individual drusen lesions. The qAF levels were measured from the perifoveal annular ring (quantitative autofluorescence 8 [qAF8]) using the Delori grid, as well as focally over individual drusen lesions in this region. The association between qAF levels and age, sex, and drusen presence and volume were determined using multivariable regression analysis. Results: Mean qAF levels increased with age (P < 0.001) and were higher in females (P = 0.047). Eyes with soft drusen exhibited reduced mean qAF compared with age-matched normal eyes (P = 0.003), with greater drusen volume showing a trend toward decreased qAF levels. However, qAF levels are focally increased over most individual drusen (P < 0.001), with larger drusen appearing more hyperautofluorescent (R2 = 0.391, P < 0.001). Conclusions: In rhesus macaques, qAF levels are increased with age and female sex, but decreased in eyes with soft drusen, similar to human AMD. However, drusen lesions appear hyperautofluorescent unlike those in humans, suggesting similarities and differences in RPE lipofuscin between humans and NHPs that may provide insight into drusen biogenesis and AMD pathogenesis.


Assuntos
Envelhecimento/patologia , Angiofluoresceinografia/métodos , Degeneração Macular/complicações , Oftalmoscopia/métodos , Drusas Retinianas/patologia , Epitélio Pigmentado da Retina/patologia , Tomografia de Coerência Óptica/métodos , Animais , Modelos Animais de Doenças , Fundo de Olho , Macaca mulatta , Degeneração Macular/patologia , Drusas Retinianas/etiologia
10.
Traffic Inj Prev ; 20(4): 442-448, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31074635

RESUMO

Objectives: We combine data on roads and crash characteristics to identify patterns in road traffic crashes with regard to road characteristics. We illustrate how combined analysis of data regarding road maintenance, maintenance costs, road characteristics, crash characteristics, and geographical location can enrich road maintenance prioritization from a traffic safety perspective. Methods: The study is based on traffic crash data merged with road maintenance data and annual average daily traffic (AADT) collected in Denmark. We analyzed 3,964 crashes that occurred from 2010 to 2015. A latent class clustering (LCC) technique was used to identify crash clusters with different road and crash characteristics. The distribution of crash severity and estimated road maintenance costs for each cluster was found and cluster differences were compared using the chi-square test. Finally, a map matching procedure was used to identify the geographical distribution of the crashes in each cluster. Results: Results showed that based on road maintenance levels there was no difference in the distribution of crash severity. The LCC technique revealed 11 crash clusters. Five clusters were characterized by crashes on roads with a poor maintenance level (levels 4 and 3). Only a few of these crashes included a vulnerable road user (VRU) but many occurred on roads without barriers. Four clusters included a large share of crashes on acceptably maintained roads (level 2). For these clusters only small variations in road characteristics were found, whereas the differences in crash characteristics were more dominant. The last 2 clusters included crashes that mainly occurred on new roads with no need for maintenance (level 1). Injury severity, estimated maintenance costs, and geographical location were found to be differently distributed for most of the clusters. Conclusions: We find that focusing solely on road maintenance and crash severity does not provide clear guidance of how to prioritize between road maintenance efforts from a traffic safety perspective. However, when combined with geographical location and crash characteristics, a more nuanced picture appears that allows consideration of different target groups and perspectives.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Segurança/estatística & dados numéricos , Análise por Conglomerados , Dinamarca , Humanos
11.
Rev Sci Instrum ; 87(11): 115108, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910610

RESUMO

Spin polarized 3He gas is currently widely used in various scientific fields and in medical diagnosis applications. The spin polarization of 3He nuclei can be achieved by spin-exchange optical pumping (SEOP). In SEOP, the 3He gas is enclosed in a glass cell together with alkali metals and is then heated to maintain the alkali metal vapor pressures at the appropriate levels. However, polarized 3He gas is highly sensitive to any inhomogeneity in its magnetic field, and any small field gradients caused by the heaters may cause degradation of the 3He polarization. To overcome this conflict between the heating process and the magnetic field, we have developed electrical heaters that essentially cause no magnetic fields. These heaters are thin and are flexible enough to be bent to within a radius of a few centimeters. These carefully designed heater elements and a double layer structure effectively eliminate magnetic field generation. The heaters were originally developed for SEOP applications, but can also be applied to other processes that need to avoid unwanted magnetic fields.

12.
Traffic Inj Prev ; 17(6): 580-4, 2016 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-26786061

RESUMO

OBJECTIVE: This study aligns to the body of research dedicated to estimating the underreporting of road crash injuries and adds the perspective of understanding individual and crash factors contributing to the decision to report a crash to the police, the hospital, or both. METHOD: This study focuses on road crash injuries that occurred in the province of Funen, Denmark, between 2003 and 2007 and were registered in the police, the hospital, or both authorities. Underreporting rates are computed with the capture-recapture method, and the probability for road crash injuries in police records to appear in hospital records (and vice versa) is estimated with joint binary logit models. RESULTS: The capture-recapture analysis shows high underreporting rates of road crash injuries in Denmark and the growth of underreporting not only with the decrease in injury severity but also with the involvement of cyclists (reporting rates of about 14% for serious injuries and 7% for slight injuries) and motorcyclists (reporting rates of about 35% for serious injuries and 10% for slight injuries). Model estimates show that the likelihood of appearing in both data sets is positively related to helmet and seat belt use, number of motor vehicles involved, alcohol involvement, higher speed limit, and females being injured. CONCLUSIONS: This study adds significantly to the literature about underreporting by recognizing that understanding the heterogeneity in the reporting rate of road crashes may lead to devising policy measures aimed at increasing the reporting rate by targeting specific road user groups (e.g., males, young road users) or specific situational factors (e.g., slight injuries, arm injuries, leg injuries, weekend).


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Registros/normas , Adolescente , Adulto , Dinamarca/epidemiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Registro Médico Coordenado , Polícia , Ferimentos e Lesões/epidemiologia , Ferimentos e Lesões/terapia , Adulto Jovem
13.
Cancer Sci ; 105(8): 996-1001, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24850362

RESUMO

Carcinoembryonic antigen (CEA) affects tumorigenesis by enhancing tumor cell survival and by inducing tumor angiogenesis. This study aimed to evaluate baseline CEA serum levels to predict bevacizumab-based therapy effect and survival in patients with metastatic colorectal cancer (mCRC). Two hundred and ninety eight mCRC patients receiving chemotherapy plus either bevacizumab or cetuximab were analyzed in a retrospective study. Disease control (DC), progression-free survival (PFS), and overall survival were assessed and related to pretreatment CEA serum levels. Patients with baseline CEA serum levels below the statistical median of 26.8 ng/mL (group I) were compared with patients with higher CEA levels (group II). The cetuximab-based treatment cohort was analyzed for specificity assessment of CEA to predict the anti-vascular endothelial growth factor effect in mCRC. Baseline CEA serum levels inversely correlated with therapeutic response in patients receiving bevacizumab-based treatment (disease control rate, 84% vs 60%), inversely correlated with median PFS leading to a median PFS benefit of 2.1 months for patients in group I when compared with group II, as well as inversely correlated with median overall survival (37.5 months vs 21.4 months). In an independent cohort of 129 patients treated with cetuximab-based therapy, no association of therapeutic response or PFS with CEA serum levels was found. As expected, baseline CEA levels were prognostic for mCRC. These data give first evidence that baseline serum CEA levels might constitute an important predictor for the efficacy of first-line bevacizumab-based therapy in patients with mCRC.


Assuntos
Antígeno Carcinoembrionário/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Idoso , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab , Biomarcadores Tumorais/análise , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
14.
Cancer Res ; 73(22): 6584-96, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24121495

RESUMO

Carcinoembryonic antigen (CEA, CD66e, CEACAM-5) is a cell-surface-bound glycoprotein overexpressed and released by many solid tumors that has an autocrine function in cancer cell survival and differentiation. Soluble CEA released by tumors is present in the circulation of patients with cancer, where it is used as a marker for cancer progression, but whether this form of CEA exerts any effects in the tumor microenvironment is unknown. Here, we present evidence that soluble CEA is sufficient to induce proangiogenic endothelial cell behaviors, including adhesion, spreading, proliferation, and migration in vitro and tumor microvascularization in vivo. CEA-induced activation of endothelial cells was dependent on integrin ß-3 signals that activate the focal-adhesion kinase and c-Src kinase and their downstream MAP-ERK kinase/extracellular signal regulated kinase and phosphoinositide 3-kinase/Akt effector pathways. Notably, while interference with VEGF signaling had no effect on CEA-induced endothelial cell activation, downregulation with the CEA receptor in endothelial cells attenuated CEA-induced signaling and tumor angiogenesis. Corroborating these results clinically, we found that tumor microvascularization was higher in patients with colorectal cancer exhibiting higher serum levels of soluble CEA. Together, our results elucidate a novel function for soluble CEA in tumor angiogenesis.


Assuntos
Antígeno Carcinoembrionário/metabolismo , Neoplasias/irrigação sanguínea , Neovascularização Patológica/metabolismo , Animais , Antígeno Carcinoembrionário/química , Antígeno Carcinoembrionário/farmacologia , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos Transgênicos , Neoplasias/patologia , Solubilidade , Células Tumorais Cultivadas
15.
Mol Immunol ; 45(5): 1308-17, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17964653

RESUMO

House dust mite allergy occurs in 10-20% of the population. Improvement of the present immunotherapy requires detailed knowledge about the structure of the allergens. Mimotopes selected from phage peptide libraries imitate the conformational epitopes of a natural allergen. The aim of our study was to generate epitope mimics for the two major allergens of house dust mite. When the monoclonal anti-Der p 1 and anti-Der p 2 antibodies were used for biopannings, mimotopes were selected which bound also specific IgE from human allergic patients' sera. The conformational matching of these mimotopes on the 3D structure of the natural allergens determined discontinuous epitopes in both cases, representing conformational B-cell epitopes relevant for binding of human IgE. Therefore, these mimotopes are potential candidates for the directed induction of blocking antibodies and epitope-specific immunotherapy of mite allergy.


Assuntos
Antígenos de Dermatophagoides/imunologia , Epitopos de Linfócito B/imunologia , Mimetismo Molecular , Animais , Proteínas de Artrópodes , Cisteína Endopeptidases , Humanos , Hipersensibilidade/terapia , Imunoglobulina E/metabolismo , Imunoterapia , Biblioteca de Peptídeos , Conformação Proteica
16.
Mech Ageing Dev ; 129(3): 120-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18083215

RESUMO

Recent studies indicated an underestimation of allergies in elderly. In our experimental food allergy model of protein feeding under acid-suppression we aimed to assess whether food allergy can be induced in immunosenescent mice. Furthermore, the impact of gastric digestion on celery allergenicity was evaluated in aged patients. Measurements of serum zinc and iron levels in senescent and adult BALB/c mice for definition of the nutritional status indicated a possible alteration of the immune response in the aged animals due to reduced zinc and iron levels. Feedings of mice with digestion-sensitive celery proteins under physiological gastric conditions induced IgG1 and IgG2a in the aged and preferentially IgG1 in the adult animals. In contrast, incomplete digestion due to acid-suppression rendered celery-specific IgE, positive skin tests and elevated IL-5 levels in both age groups. Also in aged celery allergic patients (mean age 72 years) properly digested celery showed decreased capacity to bind and crosslink IgE as evaluated by skin tests and IgE immunoblot. Thus, in the geriatric murine model, celery allergy was induced only if gastric digestion was hindered. Accordingly, gastric proteolysis decreased in vitro and in vivo IgE-reactivity against celery proteins in aged allergic patients.


Assuntos
Envelhecimento/imunologia , Apium/imunologia , Hipersensibilidade Alimentar/imunologia , Idoso , Envelhecimento/sangue , Animais , Antiulcerosos/farmacologia , Citocinas/biossíntese , Feminino , Hipersensibilidade Alimentar/etiologia , Humanos , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Ferro/sangue , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Pepsina A/metabolismo , Proteínas de Plantas/imunologia , Proteínas de Plantas/metabolismo , Fatores de Risco , Testes Cutâneos , Células Th2/imunologia , Zinco/sangue
17.
Clin Cancer Res ; 13(21): 6501-8, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17975163

RESUMO

PURPOSE: The carcinoembryonic antigen (CEA) is a glycoprotein that is overexpressed in nearly 50% of all human and veterinarian tumors. At present, anti-CEA antibodies are being tested in clinical studies as passive immunotherapeutics. This study aims to establish an active immunotherapy for the poorly immunogenic CEA glycoprotein by generating antigen surrogates. EXPERIMENTAL DESIGN: We used the monoclonal anti-CEA antibody Col-1 and the biopanning method to generate peptide mimics (mimotopes) of the Col-1 epitope. The peptide showing the highest specificity and mimicry was synthesized as an octameric multiple antigenic mimotope (MAM). Subsequently, immunogenicity of the selected mimotope was examined in BALB/c mice. We assessed antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity mediated by the induced antibodies on CEA-expressing HT29 tumor cells. Furthermore, after immunization, the BALB/c mice were transplanted s.c. with Meth-A/CEA tumor cells. RESULTS: When BALB/c mice were immunized with this MAM, they generated a specific humoral immune response against CEA. The mimotope-induced polyclonal and poly-isotypic antibodies induced antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity in vitro. Furthermore, when MAM-immunized mice were transplanted s.c. with Meth-A/CEA cells expressing human CEA, a suppressed tumor growth was observed. CONCLUSION: From our results, we can conclude that the Col-1 epitope of the glycoprotein CEA can be translated into an immunogenic peptide mimic. The mimotope-induced antibodies recognize CEA and do effectively inhibit growth of CEA-positive tumors. Based on these finding, we suggest that the generated mimotopes are candidates for active immunotherapy of CEA-expressing tumors.


Assuntos
Antígeno Carcinoembrionário/química , Regulação Neoplásica da Expressão Gênica , Imunoterapia/métodos , Animais , Antígenos de Neoplasias/química , Desenho de Fármacos , Ensaio de Imunoadsorção Enzimática , Epitopos/química , Glicoproteínas/química , Sistema Imunitário , Camundongos , Camundongos Endogâmicos BALB C , Microscopia de Fluorescência , Transplante de Neoplasias , Biblioteca de Peptídeos , Peptídeos/química , Filogenia
18.
Eur J Immunol ; 36(5): 1267-74, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16568495

RESUMO

The disialoganglioside GD2, a carbohydrate antigen, is expressed on all tumors of neuroectodermal origin, including melanoma, neuroblastoma, sarcoma and small cell lung cancer. Due to its specific expression on tumor surfaces, GD2 is an attractive target for immunotherapies. The mouse/human chimeric anti-GD2 mAb ch14.18 is already applied in melanoma and neuroblastoma trials as a passive immunotherapy. To establish an active immunotherapy alternative, we aimed to replace the poorly immunogenic ganglioside with immunogenic peptides. Previously, we used the ch14.18 antibody to select GD2 peptide mimics from a phage display library. In the present study, two mimics of the ch14.18 epitope were coupled to keyhole limpet hemocyanin and used for immunizing BALB/c mice. Induction of a specific humoral immune response towards the original antigen GD2, both purified and expressed on neuroblastoma and melanoma cells, could be demonstrated in ELISA, Western blot, and immunofluorohistochemistry. As the elicited antibodies were of the IgG isotype, the mimotope conjugates were capable of recruiting T cell help and inducing memory phenomena. In conclusion, we show that an epitope of the carbohydrate antigen GD2 can successfully be translated into immunogenic peptide mimotopes. Our immunization experiments indicate that GD2 mimotopes are suitable for active immunotherapy of GD2-expressing tumors.


Assuntos
Anticorpos Antineoplásicos/biossíntese , Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Gangliosídeos/imunologia , Imunoglobulina G/biossíntese , Animais , Linhagem Celular Tumoral , Reações Cruzadas , Humanos , Melanoma/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Neuroblastoma/imunologia , Vacinação
19.
Dev Med Child Neurol ; 42(12): 839-42, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11132258

RESUMO

A 5-year-old boy with focal cortical dysplasia was referred to our hospital because of epileptic seizures. He showed mild weakness of the left hand without sensory disturbance. Brain MRI revealed extensive cortical dysplasia with pachygyria and microgyria around the right central sulcus. On EEG examination, interictal spikes were noted over the right fronto/centro/parietal region. A 37-channel magnetometer revealed that the sources of the spikes were in a small, restricted region of the normal frontal lobe adjacent to the dysplastic brain. Somatosensory evoked magnetic fields indicated that the location of the current source of N2O was in the same area. Our patient shows a unique case of plasticity and reorganization of the somatosensory function due to cortical dysplasia.


Assuntos
Córtex Cerebral/patologia , Epilepsia/fisiopatologia , Potenciais Somatossensoriais Evocados , Plasticidade Neuronal , Pré-Escolar , Eletroencefalografia , Epilepsia/complicações , Humanos , Masculino
20.
Eur J Pharmacol ; 168(2): 193-200, 1989 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-2606148

RESUMO

The pharmacological properties of a novel thromboxane A2/prostaglandin endoperoxide receptor antagonist, ONO-3708, on blood vessels were examined in vitro and in vivo. ONO-3708, 10 microM, inhibited the rabbit aorta contractions induced by thromboxane A2, prostaglandin H2, 11,9-epoxymethano-prostaglandin H2 (U-46619) or prostaglandin F2 alpha without affecting the contractions induced by angiotensin II, serotonin or norepinephrine. ONO-3708, at a concentration of 1 to 100 nM, appeared to be a competitive inhibitor of the contractile responses of the canine basilar artery to 9,11-epithio-11,12-methano-thromboxane A2 (STA2), U-46619 and PGF2 alpha, and a non-competitive inhibitor of the contractile responses to 15-hydroperoxy-eicosatetraenoic acid (15-HPETE). In in vivo studies, ONO-3708 (10 and 100 micrograms/kg per min i.v.) ameliorated the decrease in diameter of the basilar artery induced by the i.v. infusion of STA2 (0.1 microgram/kg per min) in cats. Furthermore, infusion of ONO-3708 (10 and 30 micrograms/kg per min i.v.) prevented the cerebral vasospasm in an experimental subarachnoid hemorrhage model in dogs. These results indicate that ONO-3708 is a potent antagonist of the thromboxane A2/prostaglandin endoperoxide receptor in vitro and in vivo and may be of therapeutic use in preventing cerebral vasospasm.


Assuntos
Vasos Sanguíneos/efeitos dos fármacos , Tromboxano A2/análogos & derivados , Tromboxano A2/antagonistas & inibidores , Animais , Aorta/fisiologia , Artéria Basilar/fisiologia , Vasos Sanguíneos/ultraestrutura , Gatos , Cães , Feminino , Ataque Isquêmico Transitório/prevenção & controle , Masculino , Contração Muscular/efeitos dos fármacos , Coelhos , Receptores de Prostaglandina/efeitos dos fármacos , Tromboxano A2/farmacologia , Vasoconstrição/efeitos dos fármacos
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