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1.
Annu Rev Immunol ; 37: 377-403, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-31026410

RESUMO

The gut-associated lymphoid tissue (GALT) faces a considerable challenge. It encounters antigens derived from an estimated 1014 commensal microbes and greater than 30 kg of food proteins yearly. It must distinguish these harmless antigens from potential pathogens and mount the appropriate host immune response. Local and systemic hyporesponsiveness to dietary antigens, classically referred to as oral tolerance, comprises a distinct complement of adaptive cellular and humoral immune responses. It is increasingly evident that a functional epithelial barrier engaged in intimate interplay with innate immune cells and the resident microbiota is critical to establishing and maintaining oral tolerance. Moreover, innate immune cells serve as a bridge between the microbiota, epithelium, and the adaptive immune system, parlaying tonic microbial stimulation into signals critical for mucosal homeostasis. Dysregulation of gut homeostasis and the subsequent disruption of tolerance therefore have clinically significant consequences for the development of food allergy.


Assuntos
Disbiose/imunologia , Hipersensibilidade Alimentar/imunologia , Microbioma Gastrointestinal/imunologia , Mucosa Intestinal/imunologia , Administração Oral , Alérgenos/imunologia , Animais , Alimentos , Hipersensibilidade Alimentar/microbiologia , Homeostase , Humanos , Tolerância Imunológica , Imunidade Inata , Mucosa Intestinal/microbiologia
2.
Annu Rev Cell Dev Biol ; 36: 511-528, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32634325

RESUMO

Pediatric allergic disease is a significant health concern worldwide, and the prevalence of childhood eczema, asthma, allergic rhinitis, and food allergy continues to increase. Evidence to support specific interventions for the prevention of eczema, asthma, and allergic rhinitis is limited, and no consensus on prevention strategies has been reached. Randomized controlled trials investigating the prevention of food allergy via oral tolerance induction and the early introduction of allergenic foods have been successful in reducing peanut and egg allergy prevalence. Infant weaning guidelines in the United Sates were recently amended to actively encourage the introduction of peanut for prevention of peanut allergy.


Assuntos
Hipersensibilidade Alimentar/imunologia , Tolerância Imunológica , Animais , Criança , Humanos , Imunoterapia , Modelos Biológicos , Hipersensibilidade a Amendoim/imunologia , Guias de Prática Clínica como Assunto
3.
Immunity ; 56(8): 1862-1875.e9, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37478853

RESUMO

Loss of oral tolerance (LOT) to gluten, driven by dendritic cell (DC) priming of gluten-specific T helper 1 (Th1) cell immune responses, is a hallmark of celiac disease (CeD) and can be triggered by enteric viral infections. Whether certain commensals can moderate virus-mediated LOT remains elusive. Here, using a mouse model of virus-mediated LOT, we discovered that the gut-colonizing protist Tritrichomonas (T.) arnold promotes oral tolerance and protects against reovirus- and murine norovirus-mediated LOT, independent of the microbiota. Protection was not attributable to antiviral host responses or T. arnold-mediated innate type 2 immunity. Mechanistically, T. arnold directly restrained the proinflammatory program in dietary antigen-presenting DCs, subsequently limiting Th1 and promoting regulatory T cell responses. Finally, analysis of fecal microbiomes showed that T. arnold-related Parabasalid strains are underrepresented in human CeD patients. Altogether, these findings will motivate further exploration of oral-tolerance-promoting protists in CeD and other immune-mediated food sensitivities.


Assuntos
Antígenos , Imunidade Inata , Animais , Camundongos , Humanos , Dieta , Glutens , Células Dendríticas , Tolerância Imunológica
4.
Immunity ; 49(1): 151-163.e5, 2018 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-29980437

RESUMO

The intestinal barrier is vulnerable to damage by microbiota-induced inflammation that is normally restrained through mechanisms promoting homeostasis. Such disruptions contribute to autoimmune and inflammatory diseases including inflammatory bowel disease. We identified a regulatory loop whereby, in the presence of the normal microbiota, intestinal antigen-presenting cells (APCs) expressing the chemokine receptor CX3CR1 reduced expansion of intestinal microbe-specific T helper 1 (Th1) cells and promoted generation of regulatory T cells responsive to food antigens and the microbiota itself. We identified that disruption of the microbiota resulted in CX3CR1+ APC-dependent inflammatory Th1 cell responses with increased pathology after pathogen infection. Colonization with microbes that can adhere to the epithelium was able to compensate for intestinal microbiota loss, indicating that although microbial interactions with the epithelium can be pathogenic, they can also activate homeostatic regulatory mechanisms. Our results identify a cellular mechanism by which the microbiota limits intestinal inflammation and promotes tissue homeostasis.


Assuntos
Receptor 1 de Quimiocina CX3C/metabolismo , Microbioma Gastrointestinal/imunologia , Mucosa Intestinal/imunologia , Sistema Fagocitário Mononuclear/imunologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Animais , Apresentação de Antígeno , Aderência Bacteriana/imunologia , Modelos Animais de Doenças , Feminino , Homeostase , Tolerância Imunológica , Imunidade nas Mucosas , Inflamação/imunologia , Doenças Inflamatórias Intestinais/imunologia , Interleucina-10/imunologia , Interleucina-10/metabolismo , Mucosa Intestinal/microbiologia , Masculino , Camundongos , Células RAW 264.7
5.
FASEB J ; 38(3): e23460, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38315443

RESUMO

Traumatic brain injury (TBI) is one of the leading causes of death worldwide. There are currently no effective treatments for TBI, and trauma survivors suffer from a variety of long-lasting health consequences. With nutritional support recently emerging as a vital step in improving TBI patients' outcomes, we sought to evaluate the potential therapeutic benefits of nutritional supplements derived from bovine thymus gland, which can deliver a variety of nutrients and bioactive molecules. In a rat model of controlled cortical impact (CCI), we determined that animals supplemented with a nuclear fraction of bovine thymus (TNF) display greatly improved performance on beam balance and spatial memory tests following CCI. Using RNA-Seq, we identified an array of signaling pathways that are modulated by TNF supplementation in rat hippocampus, including those involved in the process of autophagy. We further show that bovine thymus-derived extracts contain antigens found in neural tissues and that supplementation of rats with thymus extracts induces production of serum IgG antibodies against neuronal and glial antigens, which may explain the enhanced animal recovery following CCI through possible oral tolerance mechanism. Collectively, our data demonstrate, for the first time, the potency of a nutritional supplement containing nuclear fraction of bovine thymus in enhancing the functional recovery from TBI.


Assuntos
Lesões Encefálicas Traumáticas , Extratos do Timo , Humanos , Ratos , Animais , Bovinos , Extratos do Timo/farmacologia , Extratos do Timo/uso terapêutico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Neurônios , Neuroglia , Hipocampo , Modelos Animais de Doenças
6.
Diabetologia ; 67(1): 27-41, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37782353

RESUMO

AIMS/HYPOTHESIS: We hypothesised that islet beta cell antigen presentation in the gut along with a tolerising cytokine would lead to antigen-specific tolerance in type 1 diabetes. We evaluated this in a parallel open-label Phase 1b study using oral AG019, food-grade Lactococcus lactis bacteria genetically modified to express human proinsulin and human IL-10, as a monotherapy and in a parallel, randomised, double-blind Phase 2a study using AG019 in combination with teplizumab. METHODS: Adults (18-42 years) and adolescents (12-17 years) with type 1 diabetes diagnosed within 150 days were enrolled, with documented evidence of at least one autoantibody and a stimulated peak C-peptide level >0.2 nmol/l. Participants were allocated to interventions using interactive response technology. We treated 42 people aged 12-42 years with recent-onset type 1 diabetes, 24 with Phase 1b monotherapy (open-label) and 18 with Phase 2a combination therapy. In the Phase 2a study, after treatment of the first two open-label participants, all people involved were blinded to group assignment, except for the Data Safety Monitoring Board members and the unblinded statistician. The primary endpoint was safety and tolerability based on the incidence of treatment-emergent adverse events, collected up to 6 months post treatment initiation. The secondary endpoints were pharmacokinetics, based on AG019 detection in blood and faeces, and pharmacodynamic activity. Metabolic and immune endpoints included stimulated C-peptide levels during a mixed meal tolerance test, HbA1c levels, insulin use, and antigen-specific CD4+ and CD8+ T cell responses using an activation-induced marker assay and pooled tetramers, respectively. RESULTS: Data from 24 Phase 1b participants and 18 Phase 2a participants were analysed. No serious adverse events were reported and none of the participants discontinued AG019 due to treatment-emergent adverse events. No systemic exposure to AG019 bacteria, proinsulin or human IL-10 was demonstrated. In AG019 monotherapy-treated adults, metabolic variables were stabilised up to 6 months (C-peptide, insulin use) or 12 months (HbA1c) post treatment initiation. In participants treated with AG019/teplizumab combination therapy, all measured metabolic variables stabilised or improved up to 12 months and CD8+ T cells with a partially exhausted phenotype were significantly increased at 6 months. Circulating preproinsulin-specific CD4+ and CD8+ T cells were detected before and after treatment, with a reduction in the frequency of preproinsulin-specific CD8+ T cells after treatment with monotherapy or combination therapy. CONCLUSIONS/INTERPRETATION: Oral delivery of AG019 was well tolerated and safe as monotherapy and in combination with teplizumab. AG019 was not shown to interfere with the safety profile of teplizumab and may have additional biological effects, including changes in preproinsulin-specific T cells. These preliminary data support continuing studies with this agent alone and in combination with teplizumab or other systemic immunotherapies in type 1 diabetes. TRIAL REGISTRATION: ClinicalTrials.gov NCT03751007, EudraCT 2017-002871-24 FUNDING: This study was funded by Precigen ActoBio.


Assuntos
Diabetes Mellitus Tipo 1 , Adulto , Adolescente , Humanos , Interleucina-10 , Peptídeo C , Linfócitos T CD8-Positivos/metabolismo , Proinsulina , Método Duplo-Cego
7.
Annu Rev Genet ; 50: 595-618, 2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27893966

RESUMO

Plastid-made biopharmaceuticals treat major metabolic or genetic disorders, including Alzheimer's, diabetes, hypertension, hemophilia, and retinopathy. Booster vaccines made in chloroplasts prevent global infectious diseases, such as tuberculosis, malaria, cholera, and polio, and biological threats, such as anthrax and plague. Recent advances in this field include commercial-scale production of human therapeutic proteins in FDA-approved cGMP facilities, development of tags to deliver protein drugs to targeted human cells or tissues, methods to deliver precise doses, and long-term stability of protein drugs at ambient temperature, maintaining their efficacy. Codon optimization utilizing valuable information from sequenced chloroplast genomes enhanced expression of eukaryotic human or viral genes in chloroplasts and offered unique insights into translation in chloroplasts. Support from major biopharmaceutical companies, development of hydroponic production systems, and evaluation by regulatory agencies, including the CDC, FDA, and USDA, augur well for advancing this novel concept to the clinic and revolutionizing affordable healthcare.


Assuntos
Cloroplastos/genética , Engenharia Genética/métodos , Proteínas Recombinantes/farmacologia , Vacinas de DNA/farmacologia , Administração Oral , Doença de Alzheimer/tratamento farmacológico , Animais , Expressão Gênica , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Hemofilia A/tratamento farmacológico , Humanos , Hipertensão/tratamento farmacológico , Plantas Geneticamente Modificadas , Plastídeos/genética , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/genética
8.
Biochem Biophys Res Commun ; 674: 117-123, 2023 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-37419032

RESUMO

The liver is a tolerogenic organ that exhibits hypo-responsiveness to antigens circulating in the portal vein. Antigens that are orally administered at high doses reach the liver. In our previous study, we demonstrated that administering ovalbumin (OVA) orally at high doses generates unique CD4+ T cells and tolerogenic dendritic cells, both of which can suppress T helper type 1 (Th1) responses, in the livers of two groups of mice: DO11.10 mice with transgenic CD4+ T cell receptors for OVA and BALB/c mice that received OVA-specific CD4+ T cells through adoptive transfer. This study aimed to investigate whether oral administration of OVA at high doses inhibits the development of hepatitis in the presence of OVA-specific CD4+ T cells. Oral administration of OVA at high doses inhibited the development of OVA-specific and concanavalin A (Con A)-induced hepatitis in DO11.10 mice, and these effects were associated with the downregulation of Th1 responses. Furthermore, the adoptive transfer of CD4+ T cells from the liver of OVA-fed DO11.10 mice inhibited the development of Con A-induced hepatitis in recipient BALB/c mice through the downregulation of Th1 responses. Finally, oral administration of OVA at high doses inhibited the development of Con A-induced hepatitis in BALB/c mice bearing naïve OVA-specific CD4+ T cells. These results suggest that the oral administration of antigens at high doses suppresses Th1-mediated hepatitis in an antigen-non-specific manner in the presence of antigen-specific CD4+ T cells.


Assuntos
Hepatite , Interferon gama , Camundongos , Animais , Ovalbumina , Camundongos Transgênicos , Concanavalina A , Antígenos , Administração Oral , Camundongos Endogâmicos BALB C
9.
Cell Immunol ; 391-392: 104742, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37423874

RESUMO

Oral immunotherapies are being developed for various autoimmune diseases and allergies to suppress immune responses in an antigen-specific manner. Previous studies have shown that anti-drug antibody (inhibitor) formation in protein replacement therapy for the inherited bleeding disorder hemophilia can be prevented by repeated oral delivery of coagulation factor antigens bioencapsulated in transplastomic lettuce cells. Here, we find that this approach substantially reduces antibody development against factor VIII in hemophilia A mice treated with adeno-associated viral gene transfer. We propose that the concept of oral tolerance can be applied to prevent immune responses against therapeutic transgene products expressed in gene therapy.


Assuntos
Hemofilia A , Tolerância Imunológica , Camundongos , Animais , Terapia Genética , Hemofilia A/genética , Hemofilia A/terapia , Fator VIII/genética , Antígenos , Anticorpos
10.
Cell Immunol ; 386: 104693, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36854214

RESUMO

Food allergy impacts up to 10 % of the population and can result in life-threatening anaphylactic reactions. The pathogenesis of food allergy is not entirely understood but the disruption in naturally occurring oral tolerance is presumed to be involved. Research has been directed not only toward prevention of food allergy but on the restoration of oral tolerance by various means including immunotherapy (oral, sublingual, and epicutaneous), as well as adjunctive therapies including biologicals and probiotics. This review paper briefly discusses the involvement of oral tolerance in the pathogenesis of food allergy and how food allergy might be prevented; however, the main focus is on the potential for restoration of oral tolerance with various treatment modalities (oral immunotherapy with and without adjunctive therapies).


Assuntos
Hipersensibilidade Alimentar , Probióticos , Humanos , Dessensibilização Imunológica , Hipersensibilidade Alimentar/prevenção & controle , Probióticos/uso terapêutico , Alérgenos , Administração Oral
11.
Clin Exp Allergy ; 53(9): 930-940, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37437951

RESUMO

BACKGROUND: Indoor dust (ID) is a source of peanut proteins and immunostimulatory adjuvants (e.g. LPS) that can promote airway sensitization to peanut. We aimed to determine whether a single airway exposure to peanut plus adjuvant is sufficient to prevent oral tolerance. METHODS: To determine the effect of a single priming event, C57BL/6J mice were exposed once to peanut plus adjuvant through the airway, followed by either airway or low-dose oral exposure to peanut, and assessed for peanut allergy. Oral tolerance was investigated by feeding high-dose peanut followed by airway sensitization. To determine whether a single priming could prevent oral tolerance, the high-dose peanut regimen was applied after a single airway exposure to peanut plus adjuvant. Peanut-specific IgE and IgG1 were quantified, and mice were challenged to peanut to assess allergy. Peanut-specific CD4+ memory T cells (CD4+ TCRß+ CD44hi CD154+ ) were quantified in mediastinal lymph nodes following airway priming. RESULTS: Mice co-exposed to peanut with LPS or ID through the airway were primed to develop peanut allergy after subsequent low-dose oral or airway exposures to peanut. Oral tolerance was induced in mice fed high-dose peanut prior to airway sensitization. In contrast, mice fed high-dose peanut following a single airway exposure to peanut plus adjuvant led to allergy. Peanut-specific CD4+ memory T cells were detected as early as 7 days after the single airway priming with peanut plus adjuvant, however, delaying peanut feeding even 1 day following priming led to allergy, whereas peanut feeding the same day as priming led to tolerance. CONCLUSIONS: A single airway exposure to peanut plus adjuvant is sufficient to prime the immune system to develop allergy following subsequent high-dose oral exposure. These results highlight the importance of introducing peanut as early as possible to prevent sensitization through a non-oral priming event.


Assuntos
Arachis , Hipersensibilidade a Amendoim , Camundongos , Animais , Citocinas/metabolismo , Lipopolissacarídeos , Camundongos Endogâmicos C57BL , Adjuvantes Imunológicos , Poeira , Tolerância Imunológica , Alérgenos
12.
Allergy ; 78(3): 697-713, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36089900

RESUMO

Type 2 allergen-specific T cells are essential for the induction and maintenance of allergies to foods, and Tregs specific for these allergens are assumed to be involved in their resolution. However, it has not been convincingly demonstrated whether allergen-specific Treg responses are responsible for the generation of oral tolerance in humans. We observed that sustained food allergen exposure in the form of oral immunotherapy resulted in increased frequency of Tregs only in individuals with lasting clinical tolerance. We sought to identify regulatory components of the CD4+ T-cell response to food allergens by studying their functional activation over time in vitro and in vivo. Two subsets of Tregs expressing CD137 or CD25/OX40 were identified with a delayed kinetics of activation compared with clonally enriched pathogenic effector Th2 cells. Treg activation was dependent on IL-2 derived from effector T cells. In vivo exposure to peanut in the form of an oral food challenge of allergic subjects induced a delayed and persistent activation of Tregs after initiation of the allergen-specific Th2 response. The novel finding of our work is that a sustained wave of Treg activation is induced by the release of IL-2 from Th2 effector cells, with the implication that therapeutic administration of IL-2 could improve current OIT approaches.


Assuntos
Hipersensibilidade Alimentar , Linfócitos T Reguladores , Humanos , Alérgenos , Células Th2 , Interleucina-2
13.
Int Immunol ; 34(7): 343-352, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35303081

RESUMO

CX3CR1high myeloid cells in the small intestine mediate the induction of oral tolerance by driving regulatory T (Treg) cells. Bacterial metabolites, e.g. pyruvate and lactate, induce a dendrite extension of CX3CR1high myeloid cells into the intestinal lumen via GPR31. However, it remains unclear whether the pyruvate-GPR31 axis is involved in the induction of oral tolerance. Here, we show that pyruvate enhances oral tolerance in a GPR31-dependent manner. In ovalbumin (OVA)-fed Gpr31-deficient mice, an OVA-induced delayed-type hypersensitivity response was substantially induced, demonstrating the defective induction of oral tolerance in Gpr31-deficient mice. The percentage of RORγt+ Treg cells in the small intestine was reduced in Gpr31-deficient mice. In pyruvate-treated wild-type mice, a low dose of OVA efficiently induced oral tolerance. IL-10 production from intestinal CX3CR1high myeloid cells was increased by OVA ingestion in wild-type mice, but not in Gpr31-deficient mice. CX3CR1high myeloid cell-specific IL-10-deficient mice showed a defective induction of oral tolerance to OVA and a decreased accumulation of OVA-specific Treg cells in the small intestine. These findings demonstrate that pyruvate enhances oral tolerance through a GPR31-dependent effect on intestinal CX3CR1high myeloid cells.


Assuntos
Hipersensibilidade Tardia , Tolerância Imunológica , Ácido Pirúvico , Receptores Acoplados a Proteínas G , Administração Oral , Animais , Receptor 1 de Quimiocina CX3C , Hipersensibilidade Tardia/induzido quimicamente , Hipersensibilidade Tardia/prevenção & controle , Interleucina-10 , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Ácido Pirúvico/metabolismo , Receptores Acoplados a Proteínas G/genética , Linfócitos T Reguladores/metabolismo
14.
Trends Immunol ; 41(11): 967-971, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33036909

RESUMO

Food sensitivities are on the rise worldwide. Peripheral induced regulatory T cells (pTreg cells) play a central role in oral tolerance to dietary antigens and can contribute to preventing the onset of immune-mediated food sensitivities. Here, we discuss the potential of microbial-derived products in promoting pTreg cell proliferation for re-establishing oral tolerance in immune-mediated food sensitivities.


Assuntos
Dieta , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Alimentar/microbiologia , Linfócitos T Reguladores , Proliferação de Células , Hipersensibilidade Alimentar/prevenção & controle , Humanos , Tolerância Imunológica/imunologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologia
15.
Crit Rev Food Sci Nutr ; : 1-16, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37313721

RESUMO

The goal of food allergy (FA) prevention and treatment is to induce oral tolerance (OT). Appropriate nutritional interventions are essential to induce OT to food allergens. This review introduces the mechanism of OT and the importance of early nutritional interventions, and then firstly summarizes specific nutritional factors to induce the development of OT of FA, including proteins, vitamins, fatty acids, saccharides and probiotics. The regulatory mechanism mainly induces the development of tolerance by increasing local or systemic protective regulatory T cells (Tregs) to suppress FA, while the gut microbiota may also be changed to maintain intestinal homeostasis. For allergens-specific OT, the disruption to the structure of proteins and epitopes is critical for the induction of tolerance by hydrolyzed and heated proteins. Vitamins (vitamin A, D), fatty acids, saccharides and probiotics as allergens nonspecific OT also induce the development of OT through immunomodulatory effects. This review contributes to our understanding of OT in FA through nutritional interventions. Nutritional interventions play an important role in the induction of OT, and offer promising approaches to reduce allergy risk and alleviate FA. Moreover, due to the importance and diversity of nutrition, it must be the future trend of induction of OT in FA.

16.
J Pharmacol Sci ; 152(2): 76-85, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37169482

RESUMO

Food allergies (FAs) are caused by a failure of the immune system to regulate oral tolerance (OT). The use of soap containing hydrolyzed wheat overrides acquired OT to wheat through skin exposure. However, in mouse models, the experimental OT is robust, suggesting that acquired OT to allergens prevents the development of FAs. We aimed to analyze the mechanisms and developed a mouse model of FA that overrides acquired OT via skin exposure. Three murine FA models (intraperitoneal [IP], epicutaneous [EC], and intradermal [ID]) were compared to evaluate if allergies to ovalbumin (OVA) that had been previously tolerated orally could be induced. In the ID model, OT was overridden, and allergic reactions of severe anaphylaxis were developed. To analyze this effect in the ID model, we measured the migration of dendritic cells (DCs) into lymph nodes. The induction of OT promoted the migration of CD103+ dermal DCs; moreover, repeated percutaneous doses of OVA for sensitization gradually increased the migration of CD11b+ dermal DCs. The difference in the proportion of regulatory T cells between ID-sensitized groups at the first ID injection disappeared at the tenth injection. Although OT was robust in the IP model, ID sensitization was found to override OT.


Assuntos
Anafilaxia , Hipersensibilidade Alimentar , Camundongos , Animais , Modelos Animais de Doenças , Alérgenos , Hipersensibilidade Alimentar/etiologia , Pele , Anafilaxia/induzido quimicamente , Anafilaxia/prevenção & controle , Ovalbumina , Camundongos Endogâmicos BALB C
17.
Biol Pharm Bull ; 46(10): 1484-1489, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37599076

RESUMO

Psoriasis is classically regarded as a T-helper 1 (Th1) response-dominant disease believed to be antagonized by the Th2 response, which is responsible for allergic diseases, such as atopic dermatitis. The roles of these responses in psoriasis and the relationship between psoriasis and atopic dermatitis have received increasing attention because it is estimated that more than one million patients are concomitantly affected by psoriasis and atopic dermatitis. To address this, we attempted to determine the characteristics of imiquimod-induced psoriasiform lesions in mice with a concomitant allergic response after co-application of the unrelated allergen ovalbumin onto the skin. Imiquimod cream containing ovalbumin was successively applied to the right back skin of hairless HR female mice. Psoriasiform scores were determined for 11 d, and then, the resected skin thickness, spleen weight, and serum antibody levels were examined. In some experiments, mice were allowed free access to ovalbumin-containing water for 10 d before skin application to induce oral tolerance. Imiquimod cream induced psoriasis, and its severity increased upon simultaneous ovalbumin treatment. Increases in anti-ovalbumin immunoglobulin G2a (IgG2a) levels, a Th1 response indicator, and IgG1 and IgE levels, Th2 response indicators, were mediated by ovalbumin addition. Oral tolerance against ovalbumin effectively decreased ovalbumin-exacerbated imiquimod-induced psoriasis, in parallel with a decrease in levels of anti-ovalbumin antibodies. These results suggest that the concomitant allergic response induced by ovalbumin application exacerbates imiquimod-induced psoriasis. This implies that allergic responses to unrelated allergens might exacerbate psoriasis in humans and that modulating such responses could be an effective new approach to treat psoriasis.

18.
Contact Dermatitis ; 88(2): 109-119, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36221232

RESUMO

BACKGROUND: Adverse reactions to wheat-containing skin care products have been linked to food allergy development. OBJECTIVES: To determine the role of skin barrier dysfunction and inflammation in sensitization to gluten-derived hydrolysates via the skin in Brown Norway rats with and without oral tolerance to wheat. METHODS: Skin barrier defect was induced by mechanical disruption, and skin inflammation was induced by topical application of SLS or MC903. Unmodified, enzyme hydrolyzed, or acid hydrolyzed gluten products were applied to the skin three times per week for 5 weeks. Subsequently, rats were orally gavaged with unmodified gluten. RESULTS: Wheat-naïve rats were readily sensitized to gluten hydrolysates via the skin. Skin barrier defect and skin inflammation had little effect on the skin sensitization and hydrolysate-specific IgE levels. Oral administration of unmodified gluten promoted the production of unmodified gluten-specific IgE in rats sensitized via the skin. Sensitization through intact skin, disrupted skin barrier, or inflamed skin was unable to break tolerance to unmodified gluten in rats on a wheat-containing diet. CONCLUSIONS: Mechanical skin barrier disruption and skin inflammation play a limited role in experimental skin sensitization to gluten-derived hydrolysates.


Assuntos
Dermatite Alérgica de Contato , Glutens , Ratos , Animais , Glutens/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Pele , Inflamação , Imunoglobulina E , Alérgenos
19.
J Obstet Gynaecol Res ; 49(3): 846-851, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36482822

RESUMO

AIM: To determine the percentage of change and increment in glucose levels after a normal oral glucose tolerance test between 24 and 28 weeks of pregnancy. METHODS: We studied 3510 pregnant women who attended their obstetric delivery at a tertiary care hospital in Guadalajara, Mexico in 2018, according to characteristics and risk 1647 (47%) patients were screened for diabetes diagnosis using the oral glucose tolerance test, 501 patients reported normal values between their 24th and 28th week of pregnancy, only 400 patients had their fasting glucose level measured on the same day of their obstetric delivery, to be compared. RESULTS: Average age was 30 years, with an average of 25.3 weeks of pregnancy. The fasting serum glucose levels taken after 28 weeks of pregnancy and before the obstetrical delivery showed an increase of 1.1 mmol/L in women who develop gestational diabetes mellitus, in contrast to women who did not develop gestational diabetes mellitus after 28 weeks their blood glucose only increased on average 0.4 mmol/L. The incidence of gestational diabetes mellitus in the study population during 2018 was 32.7%. Patients who developed gestational diabetes mellitus after a normal oral glucose tolerance test had greater body mass index before the pregnancy and newborns had a higher weight than babies born to mothers without gestational diabetes mellitus. CONCLUSION: Changes in glucose levels after the oral tolerance test of normal glucose require strict monitoring, in that it was demonstrated that 3% of patients developed gestational diabetes mellitus after week 28 of gestation.


Assuntos
Diabetes Gestacional , Gravidez , Feminino , Humanos , Recém-Nascido , Adulto , Glicemia , Teste de Tolerância a Glucose , Parto , México
20.
J Allergy Clin Immunol ; 149(2): 650-658.e5, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34224785

RESUMO

BACKGROUND: Tolerance development is an important clinical outcome for infants with cow's milk allergy. OBJECTIVE: This multicenter, prospective, randomized, double-blind, controlled clinical study (NTR3725) evaluated tolerance development to cow's milk (CM) and safety of an amino acid-based formula (AAF) including synbiotics (AAF-S) comprising prebiotic oligosaccharides (oligofructose, inulin) and probiotic Bifidobacterium breve M-16V in infants with confirmed IgE-mediated CM allergy. METHODS: Subjects aged ≤13 months with IgE-mediated CM allergy were randomized to receive AAF-S (n = 80) or AAF (n = 89) for 12 months. Stratification was based on CM skin prick test wheal size and study site. After 12 and 24 months, CM tolerance was evaluated by double-blind, placebo-controlled food challenge. A logistic regression model used the all-subjects randomized data set. RESULTS: At baseline, mean ± SD age was 9.36 ± 2.53 months. At 12 and 24 months, respectively, 49% and 62% of subjects were CM tolerant (AAF-S 45% and 64%; AAF 52% and 59%), and not differ significantly between groups. During the 12-month intervention, the number of subjects reporting at least 1 adverse event did not significantly differ between groups; however, fewer subjects required hospitalization due to serious adverse events categorized as infections in the AAF-S versus AAF group (9% vs 20%; P = .036). CONCLUSIONS: After 12 and 24 months, CM tolerance was not different between groups and was in line with natural outgrowth. Results suggest that during the intervention, fewer subjects receiving AAF-S required hospitalization due to infections.


Assuntos
Aminoácidos/administração & dosagem , Tolerância Imunológica , Fórmulas Infantis , Hipersensibilidade a Leite/imunologia , Método Duplo-Cego , Feminino , Humanos , Lactente , Fórmulas Infantis/efeitos adversos , Recém-Nascido , Masculino , Estudos Prospectivos , Simbióticos/administração & dosagem
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