Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Mol Cancer Ther ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814440

RESUMO

Advanced urinary bladder cancer (BC) is characterized by rapid progression and development of therapy resistance. About 30% of the patients are diagnosed with high-grade tumors (Grade >T2a). A typical non-surgical treatment is systemic chemotherapy using Cisplatin (C) and Gemcitabine (G). However, treatment failure and subsequent disease progression are common in treated patients, and adjuvant therapies are not significantly effective. The therapeutic potential of a molecular hybrid of Ursolic Acid (UA), a pentacyclic-triterpene conjugated to N-methyl piperazine (UA4), was tested on both naïve (WT) and Gemcitabine-resistant (GemR) variants of two human invasive BC cell lines, 5637 and T24. UA4 killed 5637 (4µM), T24 (4µM) WT, and GemR cells invitro at equal potency. Pretreatment with UA4 followed by G synergistically killed WT and GemR cells by >50% compared to G followed by UA4. Oral gavage of UA4 (100 mg/kg) inhibited WT and GemR tumor growth in athymic mice. UA4 + G was more effective against GemR tumors than either drug alone. Studies revealed cytotoxic autophagy as a mechanism of UA4 cytotoxicity. UA4 induced moderate apoptosis in T24 but not in 5637 cells. Mitochondrial integrity and function were most affected by UA4 due to high levels of reactive oxygen species (ROS), disruption of mitochondrial membrane, and cell cycle arrest. These effects were enhanced in the UA4+G combination. UA4 was well-tolerated in mice, and oral gavage led to a serum level >1µM with no systemic toxicity. These results show the potential of UA4 as a non-toxic alternative treatment for high-grade BC.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38670261

RESUMO

BACKGROUND: Egg allergy is common and caused by sensitization to ovomucoid and/or ovalbumin. Many egg-allergic patients are able to tolerate eggs baked into other foods, such as muffins. Although heating egg extensively reduces allergens, the effect of other food ingredients on allergenicity of eggs, or the "matrix effect," is less well studied. OBJECTIVE: We aimed to define how food matrices impact the matrix effect in egg allergenicity. METHODS: Enzyme-linked immunosorbent assay was used to quantify ovalbumin and ovomucoid in extracts from various baked egg products: plain baked egg without a matrix, and muffins baked using either wheat flour, rice flour, or a wheat flour/banana puree mix. Allergen-specific immunoglobulin E (IgE)-blocking enzyme-linked immunosorbent assays were performed using the egg product extracts on egg-allergic patient sera to determine whether the amount of extracted egg protein in each extract correlated with how well the extracts could bind patients' egg IgE. RESULTS: Baking eggs in any muffin matrix led to an increase in the amount of extractable ovalbumin and a decrease in the amount of extractable ovomucoid compared with plain baked egg. Compared with wheat muffins, rice muffins had more extractable ovalbumin and wheat/banana muffins had more extractable ovalbumin and ovomucoid. The egg allergens in the extracts were able to block egg-allergic patients' egg IgE. CONCLUSIONS: Food matrices affect egg allergen availability. Patients and families should be advised that substitutions in baked egg muffin recipes can affect the amount of egg allergens in foods and potentially affect the risk of food allergic reaction.

3.
Mucosal Immunol ; 17(3): 431-449, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38159726

RESUMO

Dedicator of cytokinesis 8 (DOCK8) mutations lead to a primary immunodeficiency associated with recurrent gastrointestinal infections and poor antibody responses but, paradoxically, heightened IgE to food antigens, suggesting that DOCK8 is central to immune homeostasis in the gut. Using Dock8-deficient mice, we found that DOCK8 was necessary for mucosal IgA production to multiple T cell-dependent antigens, including peanut and cholera toxin. Yet DOCK8 was not necessary in T cells for this phenotype. Instead, B cell-intrinsic DOCK8 was required for maintenance of antigen-specific IgA-secreting plasma cells (PCs) in the gut lamina propria. Unexpectedly, DOCK8 was not required for early B cell activation, migration, or IgA class switching. An unbiased interactome screen revealed novel protein partners involved in metabolism and apoptosis. Dock8-deficient IgA+ B cells had impaired cellular respiration and failed to engage glycolysis appropriately. These results demonstrate that maintenance of the IgA+ PC compartment requires DOCK8 and suggest that gut IgA+ PCs have unique metabolic requirements for long-term survival in the lamina propria.


Assuntos
Fatores de Troca do Nucleotídeo Guanina , Imunoglobulina A , Mucosa Intestinal , Camundongos Knockout , Plasmócitos , Animais , Camundongos , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Imunoglobulina A/metabolismo , Imunoglobulina A/imunologia , Plasmócitos/imunologia , Plasmócitos/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Ativação Linfocitária , Linfócitos B/imunologia , Linfócitos B/metabolismo , Glicólise , Camundongos Endogâmicos C57BL , Linfócitos T/imunologia , Linfócitos T/metabolismo
4.
Sci Adv ; 9(24): eadd5002, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-37327344

RESUMO

Neurogenesis in the developing human cerebral cortex occurs at a particularly slow rate owing in part to cortical neural progenitors preserving their progenitor state for a relatively long time, while generating neurons. How this balance between the progenitor and neurogenic state is regulated, and whether it contributes to species-specific brain temporal patterning, is poorly understood. Here, we show that the characteristic potential of human neural progenitor cells (NPCs) to remain in a progenitor state as they generate neurons for a prolonged amount of time requires the amyloid precursor protein (APP). In contrast, APP is dispensable in mouse NPCs, which undergo neurogenesis at a much faster rate. Mechanistically, APP cell-autonomously contributes to protracted neurogenesis through suppression of the proneurogenic activator protein-1 transcription factor and facilitation of canonical WNT signaling. We propose that the fine balance between self-renewal and differentiation is homeostatically regulated by APP, which may contribute to human-specific temporal patterns of neurogenesis.


Assuntos
Precursor de Proteína beta-Amiloide , Células-Tronco Neurais , Humanos , Camundongos , Animais , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Diferenciação Celular , Neurônios/metabolismo , Neurogênese
5.
Cell Mol Life Sci ; 80(6): 150, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37184603

RESUMO

Amyotrophic lateral sclerosis (ALS) is the most common motor neuron (MN) disease in adults with no curative treatment. Neurofilament (NF) level in patient' fluids have recently emerged as the prime biomarker of ALS disease progression, while NF accumulation in MNs of patients is the oldest and one of the best pathological hallmarks. However, the way NF accumulations could lead to MN degeneration remains unknown. To assess NF accumulations and study the impact on MNs, we compared MNs derived from induced pluripotent stem cells (iPSC) of patients carrying mutations in C9orf72, SOD1 and TARDBP genes, the three main ALS genetic causes. We show that in all mutant MNs, light NF (NF-L) chains rapidly accumulate in MN soma, while the phosphorylated heavy/medium NF (pNF-M/H) chains pile up in axonal proximal regions of only C9orf72 and SOD1 MNs. Excitability abnormalities were also only observed in these latter MNs. We demonstrate that the integrity of the MN axonal initial segment (AIS), the region of action potential initiation and responsible for maintaining axonal integrity, is impaired in the presence of pNF-M/H accumulations in C9orf72 and SOD1 MNs. We establish a strong correlation between these pNF-M/H accumulations, an AIS distal shift, increased axonal calibers and modified repartition of sodium channels. The results expand our understanding of how NF accumulation could dysregulate components of the axonal cytoskeleton and disrupt MN homeostasis. With recent cumulative evidence that AIS alterations are implicated in different brain diseases, preserving AIS integrity could have important therapeutic implications for ALS.


Assuntos
Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Filamentos Intermediários , Superóxido Dismutase-1/genética , Proteína C9orf72/genética , Neurônios Motores/patologia
6.
NPJ Sci Food ; 7(1): 6, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36944630

RESUMO

To date, analog methods of cooking such as by grills, cooktops, stoves and microwaves have remained the world's predominant cooking modalities. With the continual evolution of digital technologies, however, laser cooking and 3D food printing may present nutritious, convenient and cost-effective cooking opportunities. Food printing is an application of additive manufacturing that utilizes user-generated models to construct 3D shapes from edible food inks and laser cooking uses high-energy targeted light for high-resolution tailored heating. Using software to combine and cook ingredients allows a chef to more easily control the nutrient content of a meal, which could lead to healthier and more customized meals. With more emphasis on food safety following COVID-19, food prepared with less human handling may lower the risk of foodborne illness and disease transmission. Digital cooking technologies allow an end consumer to take more control of the macro and micro nutrients that they consume on a per meal basis and due to the rapid growth and potential benefits of 3D technology advancements, a 3D printer may become a staple home and industrial cooking device.

7.
Sci Transl Med ; 14(671): eabq0599, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36383680

RESUMO

ImmunoglobulinA (IgA) is the predominant antibody isotype in the gut, where it regulates commensal flora and neutralizes toxins and pathogens. The function of food-specific IgA in the gut is unknown but is presumed to protect from food allergy. Specifically, it has been hypothesized that food-specific IgA binds ingested allergens and promotes tolerance by immune exclusion; however, the evidence to support this hypothesis is indirect and mixed. Although it is known that healthy adults have peanut-specific IgA in the gut, it is unclear whether children also have gut peanut-specific IgA. We found in a cohort of non-food-allergic infants (n = 112) that there is detectable stool peanut-specific IgA that is similar to adult quantities of gut peanut-specific IgA. To investigate whether this peanut-specific IgA is associated with peanut tolerance, we examined a separate cohort of atopic children (n = 441) and found that gut peanut-specific IgA does not predict protection from development of future peanut allergy in infants nor does it correlate with concurrent oral tolerance of peanut in older children. We observed higher plasma peanut-specific IgA in those with peanut allergy. Similarly, egg white-specific IgA was detectable in infant stools and did not predict egg tolerance or outgrowth of egg allergy. Bead-based epitope assay analysis of gut peanut-specific IgA revealed similar epitope specificity between children with peanut allergy and those without; however, gut peanut-specific IgA and plasma peanut-specific IgE had different epitope specificities. These findings call into question the presumed protective role of food-specific IgA in food allergy.


Assuntos
Hipersensibilidade Alimentar , Hipersensibilidade a Amendoim , Criança , Lactente , Adulto , Humanos , Arachis , Alérgenos , Imunoglobulina A , Epitopos
8.
Dev Neurobiol ; 82(1): 41-63, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34705331

RESUMO

Mammalian TRPC5 channels are predominantly expressed in the brain, where they increase intracellular Ca2+ and induce depolarization. Because they augment presynaptic vesicle release, cause persistent neural activity, and show constitutive activity, TRPC5s could play a functional role in late developmental brain events. We used immunohistochemistry to examine TRPC5 in the chick embryo brain between 8 and 20 days of incubation, and provide the first detailed description of their distribution in birds and in the whole brain of any animal species. Stained areas substantially increased between E8 and E16, and staining intensity in many areas peaked at E16, a time when chick brains first show organized patterns of whole-brain metabolic activation like what is seen consistently after hatching. Areas showing cell soma staining match areas showing Trpc5 mRNA or protein in adult rodents (cerebral cortex, hippocampus, amygdala, cerebellar Purkinje cells). Chick embryos show protein staining in the optic tectum, cerebellar nuclei, and several brainstem nuclei; equivalent areas in the Allen Institute mouse maps express Trpc5 mRNA. The strongest cell soma staining was found in a dorsal hypothalamic area (matching a group of parvicellular arginine vasotocin neurons and a pallial amygdalohypothalamic cell corridor) and the vagal motor complex. Purkinje cells showed strong dendritic staining at E20. Unexpectedly, we also describe neurite staining in the septum, several hypothalamic nuclei, and a paramedian raphe area; the strongest neurite staining was in the median eminence. These novel localizations suggest new unexplored TRPC5 functions, and possible roles in late embryonic brain development.


Assuntos
Encéfalo , Embrião de Galinha , Neurônios , Animais , Encéfalo/metabolismo , Mamíferos/metabolismo , Neuritos/metabolismo , Neurônios/metabolismo , Colículos Superiores/metabolismo , Canais de Cátion TRPC/genética , Canais de Cátion TRPC/metabolismo
9.
J Allergy Clin Immunol ; 149(1): 262-274, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34051223

RESUMO

BACKGROUND: The etiology of food allergy is poorly understood; mouse models are powerful systems to discover immunologic pathways driving allergic disease. C3H/HeJ mice are a widely used model for the study of peanut allergy because, unlike C57BL/6 or BALB/c mice, they are highly susceptible to oral anaphylaxis. However, the immunologic mechanism of this strain's susceptibility is not known. OBJECTIVE: We aimed to determine the mechanism underlying the unique susceptibility to anaphylaxis in C3H/HeJ mice. We tested the role of deleterious Toll-like receptor 4 (Tlr4) or dedicator of cytokinesis 8 (Dock8) mutations in this strain because both genes have been associated with food allergy. METHODS: We generated C3H/HeJ mice with corrected Dock8 or Tlr4 alleles and sensitized and challenged them with peanut. We then characterized the antibody response to sensitization, anaphylaxis response to both oral and systemic peanut challenge, gut microbiome, and biomarkers of gut permeability. RESULTS: In contrast to C3H/HeJ mice, C57BL/6 mice were resistant to anaphylaxis after oral peanut challenge; however, both strains undergo anaphylaxis with intraperitoneal challenge. Restoring Tlr4 or Dock8 function in C3H/HeJ mice did not protect from anaphylaxis. Instead, we discovered enhanced gut permeability resulting in ingested allergens in the bloodstream in C3H/HeJ mice compared to C57BL/6 mice, which correlated with an increased number of goblet cells in the small intestine. CONCLUSIONS: Our work highlights the potential importance of gut permeability in driving anaphylaxis to ingested food allergens; it also indicates that genetic loci outside of Tlr4 and Dock8 are responsible for the oral anaphylactic susceptibility of C3H/HeJ mice.


Assuntos
Mucosa Intestinal/metabolismo , Anafilaxia Cutânea Passiva , Hipersensibilidade a Amendoim/metabolismo , Administração Oral , Animais , Arachis/imunologia , Modelos Animais de Doenças , Feminino , Microbioma Gastrointestinal , Predisposição Genética para Doença , Fatores de Troca do Nucleotídeo Guanina/genética , Masculino , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Mutação , Anafilaxia Cutânea Passiva/genética , Hipersensibilidade a Amendoim/genética , Hipersensibilidade a Amendoim/microbiologia , Permeabilidade , Especificidade da Espécie , Receptor 4 Toll-Like/genética
10.
Front Mol Neurosci ; 14: 767041, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34970118

RESUMO

Inflammation is a shared hallmark between amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). For long, studies were conducted on tissues of post-mortem patients and neuroinflammation was thought to be only bystander result of the disease with the immune system reacting to dying neurons. In the last two decades, thanks to improving technologies, the identification of causal genes and the development of new tools and models, the involvement of inflammation has emerged as a potential driver of the diseases and evolved as a new area of intense research. In this review, we present the current knowledge about neuroinflammation in ALS, ALS-FTD, and FTD patients and animal models and we discuss reasons of failures linked to therapeutic trials with immunomodulator drugs. Then we present the induced pluripotent stem cell (iPSC) technology and its interest as a new tool to have a better immunopathological comprehension of both diseases in a human context. The iPSC technology giving the unique opportunity to study cells across differentiation and maturation times, brings the hope to shed light on the different mechanisms linking neurodegeneration and activation of the immune system. Protocols available to differentiate iPSC into different immune cell types are presented. Finally, we discuss the interest in studying monocultures of iPS-derived immune cells, co-cultures with neurons and 3D cultures with different cell types, as more integrated cellular approaches. The hope is that the future work with human iPS-derived cells helps not only to identify disease-specific defects in the different cell types but also to decipher the synergistic effects between neurons and immune cells. These new cellular tools could help to find new therapeutic approaches for all patients with ALS, ALS-FTD, and FTD.

11.
NPJ Sci Food ; 5(1): 24, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471119

RESUMO

Additive manufacturing of food is a method of creating three-dimensional edible products layer-by-layer. While food printers have been in use since 2007, commercial cooking appliances to simultaneously cook and print food layers do not yet exist. A key challenge has been the spatially controlled delivery of cooking energy. Here, we explore precision laser cooking which offers precise temporal and spatial control over heat delivery and the ability to cook, broil, cut and otherwise transform food products via customized software-driven patterns, including through packaging. Using chicken as a model food, we combine the cooking capabilities of a blue laser (λ = 445 nm), a near-infrared (NIR) laser (λ = 980 nm), and a mid-infrared (MIR) laser (λ = 10.6 µm) to broil printed chicken and find that IR light browns more efficiently than blue light, NIR light can brown and cook foods through packaging, laser-cooked foods experience about 50% less cooking loss than foods broiled in an oven, and calculate the cooking resolution of a laser to be ~1 mm. Infusing software into the cooking process will enable more creative food design, allow individuals to more precisely customize their meals, disintermediate food supply chains, streamline at-home food production, and generate horizontal markets for this burgeoning industry.

12.
Curr Opin Allergy Clin Immunol ; 21(3): 269-277, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33840798

RESUMO

PURPOSE OF REVIEW: The prevalence of food allergy is increasing on a global scale, and therefore increased attention is being paid to specific food allergy epidemiology and management. There has been a large amount of progress made in the last decade on human trials of wheat oral immunotherapy (WOIT). RECENT FINDINGS: To date, there has been one multicenter, double-blind, randomized controlled trial of WOIT, one randomized, noncontrolled trial of WOIT, and several smaller, nonrandomized clinical trials of WOIT. WOIT trials are generally limited by smaller sample sizes, affecting the demographic skew of evaluated patients. In addition, there is minimal standardization of efficacy and safety outcomes between trial protocols, making head-to-head comparison challenging. However, some common themes emerge. The majority of WOIT regimens result in successful desensitization, and success is more likely with higher maintenance dosing for longer periods of time. Limited studies have looked at sustained unresponsiveness in WOIT. WOIT can induce allergic reactions, including anaphylaxis, but more severe reactions often have an associated augmenting factor, such as exercise. Lower maintenance doses likely are associated with less severe reactions, and food modification and/or adjunct therapeutics may also decrease the risk of reactions. SUMMARY: WOIT trials are ongoing and will optimize updosing protocols and maintenance doses to improve efficacy and safety.


Assuntos
Dessensibilização Imunológica , Hipersensibilidade Alimentar , Imunoterapia , Triticum , Administração Oral , Alérgenos , Hipersensibilidade Alimentar/terapia , Humanos , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Sci Immunol ; 5(47)2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32385053

RESUMO

Immunoglobulin A (IgA) is the dominant antibody isotype in the gut and has been shown to regulate microbiota. Mucosal IgA is also widely believed to prevent food allergens from penetrating the gut lining. Even though recent work has elucidated how bacteria-reactive IgA is induced, little is known about how IgA to food antigens is regulated. Although IgA is presumed to be induced in a healthy gut at steady state via dietary exposure, our data do not support this premise. We found that daily food exposure only induced low-level, cross-reactive IgA in a minority of mice. In contrast, induction of significant levels of peanut-specific IgA strictly required a mucosal adjuvant. Although induction of peanut-specific IgA required T cells and CD40L, it was T follicular helper (TFH) cell, germinal center, and T follicular regulatory (TFR) cell-independent. In contrast, IgG1 and IgE production to peanut required TFH cells. These data suggest an alternative paradigm in which the cellular mechanism of IgA production to food antigens is distinct from IgE and IgG1. We developed an equivalent assay to study this process in stool samples from healthy, nonallergic humans, which revealed substantial levels of peanut-specific IgA that were stable over time. Similar to mice, patients with loss of CD40L function had impaired titers of gut peanut-specific IgA. This work challenges two widely believed but untested paradigms about antibody production to dietary antigens: (i) the steady state/tolerogenic response to food antigens includes IgA production and (ii) TFH cells drive food-specific gut IgA.


Assuntos
Alérgenos/imunologia , Imunoglobulina A/biossíntese , Imunoglobulina E/biossíntese , Hipersensibilidade a Amendoim/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Feminino , Imunoglobulina A/imunologia , Imunoglobulina E/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
15.
Front Immunol ; 11: 616020, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33488627

RESUMO

Food allergy now affects 6%-8% of children in the Western world; despite this, we understand little about why certain people become sensitized to food allergens. The dominant form of food allergy is mediated by food-specific immunoglobulin E (IgE) antibodies, which can cause a variety of symptoms, including life-threatening anaphylaxis. A central step in this immune response to food antigens that differentiates tolerance from allergy is the initial priming of T cells by antigen-presenting cells (APCs), primarily different types of dendritic cells (DCs). DCs, along with monocyte and macrophage populations, dictate oral tolerance versus allergy by shaping the T cell and subsequent B cell antibody response. A growing body of literature has shed light on the conditions under which antigen presentation occurs and how different types of T cell responses are induced by different APCs. We will review APC subsets in the gut and discuss mechanisms of APC-induced oral tolerance versus allergy to food identified using mouse models and patient samples.


Assuntos
Apresentação de Antígeno/imunologia , Células Apresentadoras de Antígenos/imunologia , Hipersensibilidade Alimentar/imunologia , Tolerância Imunológica/imunologia , Intestinos/imunologia , Alérgenos/imunologia , Animais , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...