Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 87
Filtrar
3.
Antibodies (Basel) ; 12(4)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37987253

RESUMO

We have previously produced a toolkit of antibodies, comprising recombinant human antibodies of all but one of the human isotypes, directed against the polcalcin family antigen Phl p 7. In this work, we complete the toolkit of human antibody isotypes with the IgD version of the anti-Phl p 7 monoclonal antibody. We also raised a set of nanobodies against the IgD anti-Phl p 7 antibody and identify and characterize one paratope-specific nanobody. This nanobody also binds to the IgE isotype of this antibody, which shares the same idiotype, and orthosterically inhibits the interaction with Phl p 7. The 2.1 Å resolution X-ray crystal structure of the nanobody in complex with the IgD Fab is described.

4.
Immunology ; 170(4): 483-494, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37530226

RESUMO

Phosphoinositide 3-kinase (PI3K) p110δ signalling negatively regulates the production of mouse IgE. However, there are disparities between the mouse and human IgE biology, and the role of PI3K p110δ in the production of human IgE is yet to be determined. To investigate the effect of PI3K p110δ inhibition in the production of human IgE we isolated human B cells from tonsil tissue and stimulated them with IL-4 and anti-CD40 antibody to induce class switching to IgE and IgG1 in the presence or absence of IC87114, a small molecule inhibitor of PI3K p110δ. Using FACS, RT-PCR and ELISA we examined the effect of PI3K p110δ inhibition on IgE production and determined the mechanisms involved. Unlike in mice, we observed that PI3K p110δ inhibition significantly reduces the number of IgE+ switched cells and the amounts of secreted IgE in IL4 and anti-CD40 cultures. However, the number of IgG1+ cells and secreted IgG1 were largely unaffected by PI3K p110δ inhibition. The expression levels of AID, ε and γ1 germinal transcripts or other factors involved in the regulation of CSR to IgE and IgG1 were also unaffected by IC87114. However, we found that IC87114 significantly decreases the proliferation of tonsil B cells stimulated with IL-4 and anti-CD40, specifically reducing the frequency of cells that had undergone 4 divisions or more. In addition, PI3K p110δ inhibition reduced the levels of IRF4 expression in IgE+ germinal centre-like B cells leading to a block in plasma cell differentiation. In conclusion, PI3K p110δ signalling is required for the production of human IgE, which makes it a pharmacological target for the treatment of allergic disease.


Assuntos
Interleucina-4 , Fosfatidilinositol 3-Quinases , Humanos , Camundongos , Animais , Interleucina-4/metabolismo , Imunoglobulina E , Antígenos CD40/genética , Antígenos CD40/metabolismo , Imunoglobulina G , Técnicas de Cultura de Células
5.
Aust Health Rev ; 47(4): 480-486, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37429819

RESUMO

Objective High-quality end-of-life care involves addressing patients' physical, psychosocial, cultural and spiritual needs. Although the measurement of the quality of care associated with dying and death is an important component of health care, there is a lack of evidence-based, systematic processes to examine the quality of dying and death of patients in hospital settings. Our purpose was to develop a systematic appraisal framework (QualDeath) for reviewing the quality of dying and death for patients with advanced cancer. The objectives were to: (1) explore the evidence regarding existing tools and processes related to appraisal of end-of-life care; (2) examine existing practices related to appraisal of quality of dying and death in hospital settings; and (3) develop QualDeath with consideration of potential acceptability and feasibility factors. Methods A co-design multiple methods approach was used. For objective 1, a rapid literature review was undertaken; for objective 2 we carried out semi-structured interviews and focus groups with key stakeholders in four major teaching hospitals; and for objective 3 we interviewed key stakeholders and held workshops with the project team to reach consensus. Results We developed QualDeath, a framework to assist hospital administrators and clinicians to systematically and retrospectively review the quality of dying and death for patients expected to die from advanced cancer. It offers four levels of potential implementation for hospitals to select from and incorporates medical record review, multidisciplinary meetings, quality of end-of-life care surveys and bereavement interviews with family carers. Conclusions The QualDeath framework provides hospitals with recommendations to formalise processes to evaluate end-of-life care. Although QualDeath was underpinned by several research methods, further research is needed to rigorously explore its impact and test its feasibility.


Assuntos
Cuidados Paliativos na Terminalidade da Vida , Neoplasias , Assistência Terminal , Humanos , Estudos Retrospectivos , Assistência Terminal/métodos , Hospitais , Neoplasias/terapia
6.
Nat Commun ; 14(1): 4180, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491373

RESUMO

All antibodies approved for cancer therapy are monoclonal IgGs but the biology of IgE, supported by comparative preclinical data, offers the potential for enhanced effector cell potency. Here we report a Phase I dose escalation trial (NCT02546921) with the primary objective of exploring the safety and tolerability of MOv18 IgE, a chimeric first-in-class IgE antibody, in patients with tumours expressing the relevant antigen, folate receptor-alpha. The trial incorporated skin prick and basophil activation tests (BAT) to select patients at lowest risk of allergic toxicity. Secondary objectives were exploration of anti-tumour activity, recommended Phase II dose, and pharmacokinetics. Dose escalation ranged from 70 µg-12 mg. The most common toxicity of MOv18 IgE is transient urticaria. A single patient experienced anaphylaxis, likely explained by detection of circulating basophils at baseline that could be activated by MOv18 IgE. The BAT assay was used to avoid enrolling further patients with reactive basophils. The safety profile is tolerable and maximum tolerated dose has not been reached, with evidence of anti-tumour activity observed in a patient with ovarian cancer. These results demonstrate the potential of IgE therapy for cancer.


Assuntos
Imunoglobulina E , Neoplasias Ovarianas , Feminino , Humanos , Anticorpos Monoclonais/efeitos adversos , Basófilos , Ácido Fólico
7.
Mol Immunol ; 159: 28-37, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37267832

RESUMO

Antibodies of the IgD isotype remain the least well characterized of the mammalian immunoglobulin isotypes. Here we report three-dimensional structures for the Fab region of IgD, based on four different crystal structures, at resolutions of 1.45-2.75 Å. These IgD Fab crystals provide the first high-resolution views of the unique Cδ1 domain. Structural comparisons identify regions of conformational diversity within the Cδ1 domain, as well as among the homologous domains of Cα1, Cγ1 and Cµ1. The IgD Fab structure also possesses a unique conformation of the upper hinge region, which may contribute to the overall disposition of the very long linker sequence between the Fab and Fc regions found in human IgD. Structural similarities observed between IgD and IgG, and differences with IgA and IgM, are consistent with predicted evolutionary relationships for the mammalian antibody isotypes.


Assuntos
Fragmentos Fab das Imunoglobulinas , Isotipos de Imunoglobulinas , Animais , Humanos , Mamíferos
8.
Nat Commun ; 14(1): 2192, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37185332

RESUMO

Outcomes for half of patients with melanoma remain poor despite standard-of-care checkpoint inhibitor therapies. The prevalence of the melanoma-associated antigen chondroitin sulfate proteoglycan 4 (CSPG4) expression is ~70%, therefore effective immunotherapies directed at CSPG4 could benefit many patients. Since IgE exerts potent immune-activating functions in tissues, we engineer a monoclonal IgE antibody with human constant domains recognizing CSPG4 to target melanoma. CSPG4 IgE binds to human melanomas including metastases, mediates tumoricidal antibody-dependent cellular cytotoxicity and stimulates human IgE Fc-receptor-expressing monocytes towards pro-inflammatory phenotypes. IgE demonstrates anti-tumor activity in human melanoma xenograft models engrafted with human effector cells and is associated with enhanced macrophage infiltration, enriched monocyte and macrophage gene signatures and pro-inflammatory signaling pathways in the tumor microenvironment. IgE prolongs the survival of patient-derived xenograft-bearing mice reconstituted with autologous immune cells. No ex vivo activation of basophils in patient blood is measured in the presence of CSPG4 IgE. Our findings support a promising IgE-based immunotherapy for melanoma.


Assuntos
Melanoma , Proteoglicanas , Humanos , Camundongos , Animais , Proteoglicanas/metabolismo , Antígenos , Proteoglicanas de Sulfatos de Condroitina , Melanoma/metabolismo , Anticorpos Monoclonais/farmacologia , Imunoglobulina E , Microambiente Tumoral
9.
Allergy ; 77(9): 2594-2617, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35152450

RESUMO

The immune system interacts with many nominal 'danger' signals, endogenous danger-associated (DAMP), exogenous pathogen (PAMP) and allergen (AAMP)-associated molecular patterns. The immune context under which these are received can promote or prevent immune activating or inflammatory mechanisms and may orchestrate diverse immune responses in allergy and cancer. Each can act either by favouring a respective pathology or by supporting the immune response to confer protective effects, depending on acuity or chronicity. In this Position Paper under the collective term danger signals or DAMPs, PAMPs and AAMPs, we consider their diverse roles in allergy and cancer and the connection between these in AllergoOncology. We focus on their interactions with different immune cells of the innate and adaptive immune system and how these promote immune responses with juxtaposing clinical outcomes in allergy and cancer. While danger signals present potential targets to overcome inflammatory responses in allergy, these may be reconsidered in relation to a history of allergy, chronic inflammation and autoimmunity linked to the risk of developing cancer, and with regard to clinical responses to anti-cancer immune and targeted therapies. Cross-disciplinary insights in AllergoOncology derived from dissecting clinical phenotypes of common danger signal pathways may improve allergy and cancer clinical outcomes.


Assuntos
Hipersensibilidade , Neoplasias , Humanos , Hipersensibilidade/diagnóstico , Hipersensibilidade/etiologia , Hipersensibilidade/terapia , Imunidade , Inflamação , Neoplasias/etiologia , Neoplasias/terapia , Transdução de Sinais
10.
Front Immunol ; 12: 702074, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721376

RESUMO

In order to better understand how the immune system interacts with environmental triggers to produce organ-specific disease, we here address the hypothesis that B and plasma cells are free to migrate through the mucosal surfaces of the upper and lower respiratory tracts, and that their total antibody repertoire is modified in a common respiratory tract disease, in this case atopic asthma. Using Adaptive Immune Receptor Repertoire sequencing (AIRR-seq) we have catalogued the antibody repertoires of B cell clones retrieved near contemporaneously from multiple sites in the upper and lower respiratory tract mucosa of adult volunteers with atopic asthma and non-atopic controls and traced their migration. We show that the lower and upper respiratory tracts are immunologically connected, with trafficking of B cells directionally biased from the upper to the lower respiratory tract and points of selection when migrating from the nasal mucosa and into the bronchial mucosa. The repertoires are characterized by both IgD-only B cells and others undergoing class switch recombination, with restriction of the antibody repertoire distinct in asthmatics compared with controls. We conclude that B cells and plasma cells migrate freely throughout the respiratory tract and exhibit distinct antibody repertoires in health and disease.


Assuntos
Antígenos/imunologia , Asma/imunologia , Linfócitos B/imunologia , Anticorpos/imunologia , Brônquios/imunologia , Movimento Celular/imunologia , Humanos , Imunoglobulina D/imunologia , Mucosa Nasal/imunologia , Plasmócitos/imunologia
11.
Cells ; 9(7)2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32645919

RESUMO

Basophils are involved in manifestations of hypersensitivity, however, the current understanding of their propensity for activation and their prognostic value in cancer patients remains unclear. As in healthy and atopic individuals, basophil populations were identified in blood from ovarian cancer patients (n = 53) with diverse tumor histologies and treatment histories. Ex vivo basophil activation was measured by CD63 expression using the basophil activation test (BAT). Irrespective of prior treatment, basophils could be activated by stimulation with IgE- (anti-FcεRI and anti-IgE) and non-IgE (fMLP) mediated triggers. Basophil activation was detected by ex vivo exposure to paclitaxel, but not to other anti-cancer therapies, in agreement with a clinical history of systemic hypersensitivity reactions to paclitaxel. Protein and gene expression analyses support the presence of basophils (CCR3, CD123, FcεRI) and activated basophils (CD63, CD203c, tryptase) in ovarian tumors. Greater numbers of circulating basophils, cells with greater capacity for ex vivo stimulation (n = 35), and gene signatures indicating the presence of activated basophils in tumors (n = 439) were each associated with improved survival in ovarian cancer. Circulating basophils in cancer patients respond to IgE- and non-IgE-mediated signals and could help identify hypersensitivity to therapeutic agents. Activated circulating and tumor-infiltrating basophils may be potential biomarkers in oncology.


Assuntos
Basófilos/metabolismo , Neoplasias Ovarianas/metabolismo , Basófilos/imunologia , Biomarcadores Tumorais/imunologia , Biomarcadores Tumorais/metabolismo , Feminino , Citometria de Fluxo , Humanos , Imunoglobulina E/metabolismo , Imunofenotipagem , Neoplasias Ovarianas/imunologia , Tetraspanina 30/metabolismo
13.
Allergy ; 75(9): 2309-2318, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32248566

RESUMO

BACKGROUND: Understanding the discrepancy between IgE sensitization and allergic reactions to peanut could facilitate diagnosis and lead to novel means of treating peanut allergy. OBJECTIVE: To identify differences in IgE and IgG4 binding to peanut peptides between peanut-allergic (PA) and peanut-sensitized but tolerant (PS) children. METHODS: PA (n = 56), PS (n = 42) and nonsensitized nonallergic (NA, n = 10) patients were studied. Synthetic overlapping 15-mer peptides of peanut allergens (Ara h 1-11) were spotted onto microarray slides, and patients' samples were tested for IgE and IgG4 binding using immunofluorescence. IgE and IgG4 levels to selected peptides were quantified using ImmunoCAP. Diagnostic model comparisons were performed using likelihood-ratio tests between each specified nominal logistic regression models. RESULTS: Seven peptides on Ara h 1, Ara h 2, and Ara h 3 were bound more by IgE of PA compared to PS patients on the microarray. IgE binding to one peptide on Ara h 5 and IgG4 binding to one Ara h 9 peptide were greater in PS than in PA patients. Using ImmunoCAP, IgE to the Ara h 2 peptides enhanced the diagnostic accuracy of Ara h 2-specific IgE. Ratios of IgG4/IgE to 4 out of the 7 peptides were higher in PS than in PA subjects. CONCLUSIONS: Ara h 2 peptide-specific IgE added diagnostic value to Ara h 2-specific IgE. Ability of peptide-specific IgG4 to surmount their IgE counterpart seems to be important in established peanut tolerance.


Assuntos
Antígenos de Plantas , Hipersensibilidade a Amendoim , Albuminas 2S de Plantas , Alérgenos , Arachis , Criança , Epitopos , Humanos , Imunoglobulina E , Hipersensibilidade a Amendoim/diagnóstico , Proteínas de Plantas
15.
Subst Abus ; 41(1): 70-76, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-29528786

RESUMO

Background: Homeless persons with substance use disorders (SUD) have high disease risk, poor access to health care, and are frequent users of Medicaid and other social services. Low-demand supportive housing with no prerequisites for treatment or sobriety has been shown to improve housing stability and decrease public service use for chronically homeless persons with serious mental illness (SMI) and chronic medical conditions. The impact of low-demand housing on individuals with SUD but without co-occurring SMI has been little studied. This evaluation compares housing retention and use of crisis public services (jail, emergency department visits, hospitalization, and substance detoxification) between individuals treated and untreated for SUD before move-in to a low-demand supportive housing program in New York City. Methods: The authors used matched administrative records for individuals with SUD but no SMI placed in supportive housing during 2007-2012. Participants received SUD treatment (n = 1425; treated participants) or were not treated (n = 512; active users) at housing application. Propensity score-weighted regression analyses were used to best estimate the effect of SUD treatment on incarceration, public service utilization, and housing retention. Results: Persons not treated for SUD had a significantly longer tenure in supportive housing than treated participants. However, not treated tenants were more likely to be incarcerated. Opioid agonist therapy and older age decreased the risk of housing discharge, whereas detoxification and inpatient SUD treatment increased the risk of discharge. Conclusions: Persons with SUD can achieve residential stability in supportive housing that does not require SUD treatment before admission.


Assuntos
Habitação , Pessoas Mal Alojadas , Setor Público , Apoio Social , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Adulto , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque , Pontuação de Propensão , Resultado do Tratamento
16.
J Immunol ; 203(7): 1693-1700, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31462504

RESUMO

An allergic reaction is rapidly generated when allergens bind and cross-link IgE bound to its receptor FcεRI on effector cells, resulting in cell degranulation and release of proinflammatory mediators. The extent of effector cell activation is linked to allergen affinity, oligomeric state, valency, and spacing of IgE-binding epitopes on the allergen. Whereas most of these observations come from studies using synthetic allergens, in this study we have used Timothy grass pollen allergen Phl p 7 and birch pollen allergen Bet v 4 to study these effects. Despite the high homology of these polcalcin family allergens, Phl p 7 and Bet v 4 display different binding characteristics toward two human patient-derived polcalcin-specific IgE Abs. We have used native polcalcin dimers and engineered multimeric allergens to test the effects of affinity and oligomeric state on IgE binding and effector cell activation. Our results indicate that polcalcin multimers are required to stimulate high levels of effector cell degranulation when using the humanized RBL-SX38 cell model and that multivalency can overcome the need for high-affinity interactions.


Assuntos
Alérgenos/imunologia , Afinidade de Anticorpos , Antígenos de Plantas/imunologia , Proteínas de Ligação ao Cálcio/imunologia , Degranulação Celular , Imunoglobulina E/imunologia , Modelos Imunológicos , Proteínas de Plantas/imunologia , Alérgenos/genética , Antígenos de Plantas/genética , Proteínas de Ligação ao Cálcio/genética , Epitopos/genética , Epitopos/imunologia , Células HEK293 , Humanos , Proteínas de Plantas/genética , Multimerização Proteica/genética , Multimerização Proteica/imunologia
18.
Front Immunol ; 10: 402, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30915071

RESUMO

IgE is secreted by plasma cells (PCs) and is central to allergic disease. Using an ex vivo tonsil B cell culture system, which mimics the Th2 responses in vivo, we have recently characterized the development pathway of human IgE-expressing PCs. In this system, as in mice, we reported the predisposition of IgE-expressing B cells to differentiate into PCs. To gain a comprehensive understanding of the molecular events involved in the differentiation of human IgE+ B cells into PCs we have used the Illumina HumanHT-12 v4 Expression BeadChip array to analyse the gene expression profile of ex vivo generated human IgE+ B cells at various stages of their differentiation into PCs. We also compared the transcription profiles of IgE+ and IgG1+ cells to discover isotype-specific patterns. Comparisons of IgE+ and IgG1+ cell transcriptional profiles revealed molecular signatures specific for IgE+ cells, which diverge from their IgG1+ cell counterparts upon differentiation into PCs. At the germinal center (GC) stage of development, unlike in some mouse studies of IgE biology, we observed similar rates of apoptosis and no significant differences in the expression of apoptosis-associated genes between the IgE+ and IgG1+ B cells. We identified a gene interaction network associated with early growth response 1 (EGR1) that, together with the up-regulated IRF4, may account for the predisposition of IgE+ B cells to differentiate into PCs. However, despite their swifter rates of PC differentiation, the transcription profile of IgE+ PCs is more closely related to IgE+ and IgG1+ plasmablasts (PBs) than to IgG1+ PCs, suggesting that the terminal differentiation of IgE+ cells is impeded. We also show that IgE+ PCs have increased levels of apoptosis suggesting that the IgE+ PCs generated in our in vitro tonsil B cell cultures, as in mice, are short-lived. We identified gene regulatory networks as well as cell cycle and apoptosis signatures that may explain the diverging PC differentiation programme of these cells. Overall, our study provides a detailed analysis of the transcriptional pathways underlying the differentiation of human IgE-expressing B cells and points to molecular signatures that regulate IgE+ PC differentiation and function.


Assuntos
Diferenciação Celular/genética , Imunoglobulina E/metabolismo , Plasmócitos/metabolismo , Transcriptoma/genética , Apoptose/genética , Células Cultivadas , Proteína 1 de Resposta de Crescimento Precoce/genética , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Centro Germinativo/imunologia , Humanos , Hipersensibilidade/metabolismo , Imunoglobulina G/metabolismo , Fatores Reguladores de Interferon/genética , Tonsila Palatina/patologia , Fenótipo
19.
Allergy ; 74(6): 1037-1051, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30636005

RESUMO

The microbiota can play important roles in the development of human immunity and the establishment of immune homeostasis. Lifestyle factors including diet, hygiene, and exposure to viruses or bacteria, and medical interventions with antibiotics or anti-ulcer medications, regulate phylogenetic variability and the quality of cross talk between innate and adaptive immune cells via mucosal and skin epithelia. More recently, microbiota and their composition have been linked to protective effects for health. Imbalance, however, has been linked to immune-related diseases such as allergy and cancer, characterized by impaired, or exaggerated immune tolerance, respectively. In this AllergoOncology position paper, we focus on the increasing evidence defining the microbiota composition as a key determinant of immunity and immune tolerance, linked to the risk for the development of allergic and malignant diseases. We discuss novel insights into the role of microbiota in disease and patient responses to treatments in cancer and in allergy. These may highlight opportunities to improve patient outcomes with medical interventions supported through a restored microbiome.


Assuntos
Asma/imunologia , Asma/microbiologia , Bactérias/metabolismo , Microbioma Gastrointestinal/imunologia , Interações entre Hospedeiro e Microrganismos/imunologia , Neoplasias/imunologia , Neoplasias/microbiologia , Animais , Asma/metabolismo , Bactérias/genética , Criança , Pré-Escolar , Dieta , Epitélio/imunologia , Epitélio/microbiologia , Feminino , Humanos , Hipótese da Higiene , Imunidade Celular , Lactente , Masculino , Micronutrientes , Mucosa/imunologia , Mucosa/microbiologia , Neoplasias/metabolismo , Filogenia
20.
Death Stud ; 43(7): 456-465, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30596350

RESUMO

Domestic Buddhist altars have long provided symbolically and materially rich media for venerating the dead in Japan. However, as Japanese household structures and funerary rites are unsettled in the contemporary era, Buddhist altars (butsudan) are rapidly being reinvented and digitalized. In this article, we describe the new technologies harnessed in butsudan production, the sensory experiences they offer, and their abilities to both reform and reinforce traditional networks of ancestral obligation. Despite promising death rituals that are more personal, secular, and affordable, the development of digitally enhanced material memorialization is still very much a work in progress in Japan.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA