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1.
Nutrients ; 15(22)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38004196

RESUMO

Microbiota colonization and development in early life is impacted by various host intrinsic (genetic) factors, but also diet, lifestyle, as well as environmental and residential factors upon and after birth. To characterize the impact of maternal nutrition and environmental factors on vaginally born infant gut microbiota composition, we performed an observational study in five distinct geographical areas in Vietnam. Fecal samples of infants (around 39 days old) and fecal and breast milk samples of their mothers (around 28 years) were collected. The microbiota composition of all samples was analyzed by 16S rRNA gene Illumina sequencing and a bioinformatics workflow based on QIIME. In addition, various breast milk components were determined. Strong associations between the geographically determined maternal diet and breast milk composition as well as infant fecal microbiota were revealed. Most notable was the association of urban Ha Noi with relatively high abundances of taxa considered pathobionts, such as Klebsiella and Citrobacter, at the expense of Bifidobacterium. Breast milk composition was most distinct in rural Ha Long Bay, characterized by higher concentrations of, e.g., docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), selenium, and vitamin B12, while it was characterized by, e.g., iron, zinc, and α-linolenic acid (ALA) in Ha Noi. Breast milk iron levels were positively associated with infant fecal Klebsiella and negatively with Bifidobacterium, while the EPA and DHA levels were positively associated with Bifidobacterium. In conclusion, differences between five regions in Vietnam with respect to both maternal breast milk and infant gut microbiota composition were revealed, most likely in part due to maternal nutrition. Thus, there could be opportunities to beneficially steer infant microbiota development in a more desired (rural instead of urban) direction through the mother's diet.


Assuntos
Microbioma Gastrointestinal , Leite Humano , Feminino , Humanos , Lactente , Leite Humano/microbiologia , Mães , Microbioma Gastrointestinal/genética , RNA Ribossômico 16S/genética , Vietnã , Ácidos Docosa-Hexaenoicos , Ferro , Aleitamento Materno , Fezes/microbiologia
2.
PLoS One ; 18(2): e0281817, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36809275

RESUMO

It is crucial for human health that the immune system of the gastrointestinal tract works effectively. Dietary modulation is one of the factors that regulate the immune response in the gut. This study aims to develop a safe human challenge model to study gastrointestinal inflammation and immune function. This study focuses on evaluating gut stimulation induced by the oral cholera vaccine in healthy people. In addition, this paper describes the study design for assessing the efficacy and safety of a probiotic lysate, identifying whether functional ingredients in food can modulate inflammatory response induced by oral cholera vaccine. Forty-six males aged 20 to 50 with healthy bowel habits will be randomly allocated to the placebo or intervention group. Participants will consume 1 capsule of probiotic lysate or placebo twice daily for 6 weeks, take oral cholera vaccines on visit 2 (day 15) and visit 5 (day 29). The level of fecal calprotectin, a marker of gut inflammation, will be the primary outcome. The changes of cholera toxin-specific antibody levels and local/systemic inflammatory responses will be evaluated in blood. The purpose of this study is to evaluate gut stimulation of the oral cholera vaccine and investigate the effect of a probiotic lysate on improving the mild inflammatory response induced by the vaccine or supporting the immune response in healthy subjects. Trial registration: * This trial is registered in the International Clinical Trials Registry Platform of WHO (ICTRP, registration number: KCT0002589).


Assuntos
Vacinas contra Cólera , Cólera , Lactobacillus plantarum , Masculino , Humanos , Cólera/prevenção & controle , Vacinação , Inflamação/tratamento farmacológico , Método Duplo-Cego
3.
PLoS One ; 18(1): e0279626, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36607972

RESUMO

The experimental challenge with attenuated enterotoxigenic E. coli strain E1392/75-2A prevents diarrhea upon a secondary challenge with the same bacteria. A dose-response pilot study was performed to investigate which immunological factors are associated with this protection. Healthy subjects were inoculated with increasing E. coli doses of 1E6-1E10 CFU, and three weeks later, all participants were rechallenged with the highest dose (1E10 CFU). Gastrointestinal discomfort symptoms were recorded, and stool and blood samples were analyzed. After the primary challenge, stool frequency, diarrhea symptom scores, and E. coli-specific serum IgG (IgG-CFA/II) titer increased in a dose-dependent manner. Fecal calprotectin and serum IgG-CFA/II response after primary challenge were delayed in the lower dose groups. Even though stool frequency after the secondary challenge was inversely related to the primary inoculation dose, all E. coli doses protected against clinical symptoms upon rechallenge. Ex vivo stimulation of PBMCs with E. coli just before the second challenge resulted in increased numbers of IL-6+/TNF-α+ monocytes and mDCs than before the primary challenge, without dose-dependency. These data demonstrate that primary E. coli infection with as few as 1E6 CFU protects against a high-dose secondary challenge with a homologous attenuated strain. Increased serum IgG-CFA/II levels and E. coli-induced mDC and monocyte responses after primary challenge suggest that protection against secondary E. coli challenges is associated with adaptive as well as innate immune responses.


Assuntos
Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Humanos , Monócitos , Projetos Piloto , Diarreia/microbiologia , Imunoglobulina G , Anticorpos Antibacterianos
4.
Nutrients ; 14(6)2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35334862

RESUMO

Infectious diseases are a major cause of morbidity and mortality worldwide. Nutritional interventions may enhance resistance to infectious diseases or help to reduce clinical symptoms. Here, we investigated whether a whey protein concentrate (WPC) could decrease diarrheagenic Escherichia coli-induced changes in reported stool frequency and gastrointestinal complaints in a double-blind, parallel 4-week intervention study. Subjects were randomly assigned to a whey hydrolysate placebo group, a low-dose WPC group or a high-dose WPC group. After 2 weeks of consumption, subjects (n = 121) were orally infected with a high dose of live but attenuated diarrheagenic E. coli (strain E1392/75-2A; 1E10 colony-forming units). Subjects recorded information on stool consistency and the frequency and severity of symptoms in an online diary. The primary outcome parameters were a change in stool frequency (stools per day) and a change in Gastrointestinal Symptom Rating Scale (GSRS) diarrhea score between the first and second days after infection. Neither dose of the whey protein concentrate in the dietary treatment affected the E. coli-induced increase in stool frequency or GSRS diarrhea score compared to placebo treatment. The composition of the microbiota shifted between the start of the study and after two weeks of consumption of the products, but no differences between the intervention groups were observed, possibly due to dietary guidelines that subjects had to adhere to during the study. In conclusion, consumption of the whey protein concentrate by healthy adults did not reduce diarrhea scores in an E. coli infection model compared to a whey hydrolysate placebo control.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Adulto , Diarreia/tratamento farmacológico , Infecções por Escherichia coli/tratamento farmacológico , Fezes , Humanos , Proteínas do Soro do Leite/farmacologia , Proteínas do Soro do Leite/uso terapêutico
5.
Sci Rep ; 11(1): 6060, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33723346

RESUMO

An experimental human challenge model with an attenuated diarrheagenic Escherichia coli (E. coli) strain has been used in food intervention studies aimed to increase resistance to E. coli infection. This study was designed to refine and expand this challenge model. In a double-blind study, healthy male subjects were orally challenged with 1E10 or 5E10 colony-forming units (CFU) of E. coli strain E1392/75-2A. Three weeks later, subjects were rechallenged with 1E10 CFU of E. coli. Before and after both challenges, clinical symptoms and infection- and immune-related biomarkers were analyzed. Subset analysis was performed on clinically high- and low-responders. Regardless of inoculation dose, the first challenge induced clinical symptoms for 2-3 days. In blood, neutrophils, CRP, CXCL10, and CFA/II-specific IgG were induced, and in feces calprotectin and CFA/II-specific IgA. Despite clinical differences between high- and low-responders, infection and immune biomarkers did not differ. The first inoculation induced protection at the second challenge, with a minor clinical response, and no change in biomarkers. The refined study design resulted in a larger dynamic range of symptoms, and identification of biomarkers induced by a challenge with the attenuated E. coli strain E1392/75-2A, which is of value for future intervention studies. Addition of a second inoculation allows to study the protective response induced by a primary infection.Clinicaltrials.gov registration: NCT02541695 (04/09/2015).


Assuntos
Diarreia , Infecções por Escherichia coli , Escherichia coli/metabolismo , Modelos Biológicos , Adolescente , Adulto , Anticorpos Antibacterianos/sangue , Biomarcadores/sangue , Proteína C-Reativa , Quimiocina CXCL1 , Diarreia/sangue , Diarreia/microbiologia , Diarreia/fisiopatologia , Método Duplo-Cego , Escherichia coli/patogenicidade , Infecções por Escherichia coli/sangue , Infecções por Escherichia coli/fisiopatologia , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Complexo Antígeno L1 Leucocitário/metabolismo , Masculino , Pessoa de Meia-Idade
6.
Allergy ; 75(7): 1710-1720, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31975472

RESUMO

BACKGROUND: Comel-Netherton syndrome (NS) is a rare autosomal disease, characterized by severe skin disease, hair shaft defects, atopic diathesis, and increased susceptibility for skin infections. Since patients with NS suffer from recurrent infections, it has been hypothesized that an underlying immunodeficiency attributes to this. Here, we studied clinical and immunological characteristics of the cohort of NS patients in the Netherlands in order to identify whether potential immunodeficiencies result in the increased risk of infectious complications. METHODS: Phenotypes were scored for severity of skin condition, specific hair shaft defects, atopy, and recurrent infections. Patients' blood samples were collected for quantification of serum immunoglobulin (Ig) levels, specific antibodies against Streptococcus pneumoniae, and allergen-specific IgE, as well as detailed immunophenotyping of blood leukocyte and lymphocyte subsets by flow cytometry. RESULTS: A total of 14 patients were included with age range 3-46 years and varying degrees of skin involvement. All patients presented with atopic symptoms (food allergy, n = 13; hay fever, n = 10; asthma, n = 7). Recurrent skin infections were common, particularly in childhood (n = 12). Low levels of specific antibodies against S pneumoniae were found in 10 of 11 evaluated patients. Detailed immunological analysis was performed on 9 adult patients. Absolute numbers of lymphocyte subsets and serum immunoglobulin levels were all within normal ranges. CONCLUSION: Multidisciplinary evaluation of our national cohort showed no evidence for a severe, clinically relevant systemic immunodeficiency. Therefore, we conclude that in Dutch NS patients the increased risk of infections most likely results from the skin barrier disruption and that increased allergen penetration predisposes to allergic sensitization.


Assuntos
Hipersensibilidade Alimentar , Síndromes de Imunodeficiência , Síndrome de Netherton , Adolescente , Adulto , Criança , Pré-Escolar , Hipersensibilidade Alimentar/diagnóstico , Humanos , Imunoglobulina E , Síndromes de Imunodeficiência/epidemiologia , Pessoa de Meia-Idade , Países Baixos , Adulto Jovem
7.
PLoS One ; 14(12): e0225825, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31830086

RESUMO

Ageing is associated with a changing immune system, leading to inflammageing (increased levels of inflammation markers in serum) and immunosenescence (reduced immune cells and reduced responses towards pathogens). This results in reduced vaccination responses and increased infections in elderly. Much is known about the adaptive immune system upon ageing, but less is known about the innate immune system. Therefore, the aim of this study was to compare innate immune function of Toll like receptor (TLR)-mediated responses between elderly and young adult women. To this end, elderly and young adult women were compared to study the effect of ageing on the relative prevalence and reactivity to TLR-mediated responses of myeloid- and plasmacytoid dendritic cells (mDC, pDC). In addition, TLR expression and inflammatory markers in serum were investigated. Elderly women had reduced numbers of circulating pDCs. In addition, pDCs and mDCs of elderly women responded differently towards TLR stimulation, especially TLR7/8 mediated stimulation was reduced, compared to young adults. In serum, markers involved in inflammation were generally increased in elderly. In conclusion, this study confirms and extends the knowledge about immunosenescence and inflammageing on innate immunity in elderly women.


Assuntos
Envelhecimento/metabolismo , Células Dendríticas/metabolismo , Células Mieloides/metabolismo , Idoso , Idoso de 80 Anos ou mais , Citocinas/sangue , Feminino , Humanos , Mediadores da Inflamação/sangue , Molécula 1 de Adesão Intercelular/sangue , Espaço Intracelular/metabolismo , Receptores Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/sangue , Molécula 1 de Adesão de Célula Vascular/sangue , Adulto Jovem
8.
Allergy ; 74(5): 986-995, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30506686

RESUMO

BACKGROUND: Peanuts are most responsible for food-induced anaphylaxis in adults in developed countries. An effective and safe immunotherapy is urgently needed. The aim of this study was to investigate the immunogenicity, allergenicity, and immunotherapeutic efficacy of a well-characterized chemically modified peanut extract (MPE) adsorbed to Al(OH)3 . METHODS: Peanut extract (PE) was modified by reduction and alkylation. Using sera of peanut-allergic patients, competitive IgE-binding assays and mediator release assays were performed. The immunogenicity of MPE was evaluated by measuring activation of human PE-specific T-cell lines and the induction of PE-specific IgG in mice. The safety and efficacy of MPE adsorbed to Al(OH)3 was tested in two mouse models by measuring allergic manifestations upon peanut challenge in peanut-allergic mice. RESULTS: Compared to PE, the IgE-binding and capacity to induce allergic symptoms of MPE were lower in all patients. PE and MPE displayed similar immunogenicity in vivo and in vitro. In mice sensitized to PE, the threshold for anaphylaxis (drop in BT) upon subcutaneous challenge with PE was 0.01 mg, while at 0.3 mg MPE no allergic reaction occurred. Anaphylaxis was not observed when PE and MPE were fully adsorbed to Al(OH)3 . Both PE and MPE + Al(OH)3 showed to be efficacious in a model for immunotherapy. CONCLUSION: In our studies, an Al(OH)3 adsorbed MPE showed reduced allergenicity compared to unmodified PE, while the efficacy of immunotherapy is maintained. The preclinical data presented in this study supports further development of modified peanut allergens for IT.


Assuntos
Antígenos de Plantas/química , Antígenos de Plantas/imunologia , Arachis/química , Arachis/imunologia , Extratos Vegetais/química , Extratos Vegetais/imunologia , Anafilaxia/imunologia , Animais , Basófilos/imunologia , Basófilos/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Mediadores da Inflamação/metabolismo , Camundongos , Hipersensibilidade a Amendoim/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
9.
Front Immunol ; 9: 2677, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30515164

RESUMO

During aging the immune system is dysregulated. Especially plasmacytoid dendritic cells (pDCs) and myeloid DCs (mDCs) have reduced Toll like receptor (TLR)-mediated responses resulting in increased susceptibility to infections. Consumption of bovine lactoferrin (bLF) has been shown to reduce infections with viruses. Galacto-oligosacharides (GOS) and vitamin D are associated with reduced pro-inflammatory cytokine levels in serum, and increased TLR7/8 responses, respectively. A double-blind placebo-controlled nutritional intervention study in elderly women was performed, to investigate the potential of bLF, GOS, and vitamin D to restore TLR responsiveness of pDCs and mDCs and to reduce inflammatory markers in serum. The nutritional intervention group (n = 15) received bLF for 3 weeks, followed by 3 weeks of bLF + GOS, and subsequently 3 weeks of bLF + GOS + vitamin D. The placebo group (n = 15) received maltodextrin for 9 weeks. Every 3 weeks, blood was collected and TLR responses of pDCs and mDCs, and inflammation-related markers in serum were measured. After 3 weeks of bLF supplementation, increased TLR7/8 and TLR1/2 responses were observed in pDCs of the nutritional intervention group compared to the placebo group. When the effects of the entire nutritional intervention were investigated, increased TLR1/2 mediated responses in mDCs were observed, and in serum sVCAM tended to decrease. Finally, based on the RAND-36 questionnaire physical function tended to improve in the intervention group. Since especially TLR7-mediated responses in pDCs were enhanced after bLF supplementation compared to placebo, this suggests that bLF may contribute to antiviral responses mediated by pDC in elderly women.Clinical trial registry number: NCT03026244, clinicaltrials.gov.


Assuntos
Células Dendríticas/imunologia , Lactoferrina/administração & dosagem , Oligossacarídeos/administração & dosagem , Receptor 7 Toll-Like/imunologia , Vitamina D/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Animais , Bovinos , Feminino , Humanos
11.
J Allergy Clin Immunol ; 138(2): 476-481.e1, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27321437

RESUMO

BACKGROUND: Recombinant human C1 inhibitor (rhC1INH) for on-demand treatment of hereditary angioedema is purified from milk of transgenic rabbits. It contains low amounts (<0.002%) of host-related impurities, which could trigger hypersensitivity reactions in patients with rabbit allergy (RA) and/or cow's milk allergy (CMA). OBJECTIVE: This study is an assessment of allergenicity and safety of rhC1INH in patients with RA and/or CMA. METHODS: Patients with CMA and/or RA underwent skin prick test (SPT), intracutaneous test (ICT), and, when results for both were negative, subcutaneous (SC) challenge with up to 2100U (14 mL) rhC1INH. The negative predictive value of the skin test protocol was calculated, defined as the ratio of patients without systemic symptoms of hypersensitivity following SC challenge, over the number of patients having tested negative for both the SPT and the ICT. Adverse events after exposure to rhC1INH were recorded. RESULTS: Twenty-six patients with RA and/or CMA were enrolled. Twenty-four had negative SPT and ICT results for rhC1INH, whereas 2 had negative SPT result but positive ICT result to rhC1INH (only the highest concentration). Twenty-two patients with negative SPT and ICT results underwent SC challenge. None developed allergic symptoms. Local treatment-emergent adverse events occurred in 7 patients (32%) after SC challenge. In 5 these were considered drug related. All were mild. CONCLUSIONS: None of the patients with negative SPT and ICT results for rhC1INH had allergic symptoms during rhC1INH challenge. The negative predictive value of the combination of SPT and ICT for the outcome of the SC challenge was 100% (95% CI, 84.6%-100%). SC administration of rhC1INH was well tolerated.


Assuntos
Angioedemas Hereditários/complicações , Proteína Inibidora do Complemento C1/efeitos adversos , Hipersensibilidade a Leite/complicações , Hipersensibilidade a Leite/imunologia , Leite/efeitos adversos , Proteínas Recombinantes/efeitos adversos , Adulto , Angioedemas Hereditários/tratamento farmacológico , Animais , Bovinos , Proteína Inibidora do Complemento C1/uso terapêutico , Feminino , Humanos , Imunoglobulina E/imunologia , Masculino , Pessoa de Meia-Idade , Hipersensibilidade a Leite/diagnóstico , Fenótipo , Coelhos , Proteínas Recombinantes/uso terapêutico , Índice de Gravidade de Doença , Testes Cutâneos , Adulto Jovem
12.
J Nutr ; 146(2): 249-55, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26701793

RESUMO

BACKGROUND: The milk-fat-globule membrane (MFGM) contains phospholipids and membrane glycoproteins that have been shown to affect pathogen colonization and gut barrier integrity. OBJECTIVE: In the present study, we determined whether commercial heat-treated MFGM can increase resistance to diarrheagenic Escherichia coli. METHODS: A randomized, placebo-controlled, double-blind, 4-wk parallel-intervention study was conducted in healthy adults. Participants were randomly assigned to a milk protein concentrate rich in MFGM [10 g Lacprodan PL-20 (Arla Foods Ingredients Group P/S), twice daily; n = 30; MFGM group) or a control [10 g Miprodan 30 (sodium caseinate), twice daily; n = 28]. After 2 wk, participants were orally challenged with live, attenuated diarrheagenic E. coli (10(10) colony-forming units). Primary outcomes were infection-induced diarrhea and fecal diarrheagenic E. coli excretion. Secondary outcomes were gastrointestinal symptoms [Gastrointestinal Symptom Rating Scale (GSRS)], stool frequency, and stool consistency (Bristol Stool Scale). RESULTS: Diarrheagenic E. coli resulted in increased fecal output, lower relative fecal dry weight, increased fecal E. coli numbers, and an increase in stool frequency and gastrointestinal complaints at day 1 after challenge. MFGM significantly decreased the E. coli-induced changes in reported stool frequency (1.1 ± 0.1 stools/d in the MFGM group; 1.6 ± 0.2 stools/d in the control group; P = 0.04) and gastrointestinal complaints at day 2 (1.1 ± 0.5 and 2.5 ± 0.6 GSRS scores in the MFGM and control groups, respectively; P = 0.05). MFGM did not affect fecal wet weight and E. coli excretion at day 2 after challenge. CONCLUSIONS: The attenuated diarrheagenic E. coli strain transiently induced mild symptoms of a food-borne infection, with complete recovery of reported clinical symptoms within 2 d. The present diarrheagenic E. coli challenge trial conducted in healthy adults indicates that a milk concentrate rich in natural, bioactive phospho- and sphingolipids from the MFGM may improve in vivo resistance to diarrheagenic E. coli. This trial was registered at clinicaltrials.gov as NCT01800396.


Assuntos
Diarreia/tratamento farmacológico , Infecções por Escherichia coli/tratamento farmacológico , Escherichia coli , Fezes/microbiologia , Glicolipídeos/uso terapêutico , Glicoproteínas/uso terapêutico , Proteínas do Leite/uso terapêutico , Leite/química , Fosfolipídeos/uso terapêutico , Adulto , Animais , Defecação/efeitos dos fármacos , Diarreia/microbiologia , Dieta , Método Duplo-Cego , Infecções por Escherichia coli/complicações , Infecções por Escherichia coli/microbiologia , Feminino , Glicolipídeos/química , Glicolipídeos/farmacologia , Glicoproteínas/química , Glicoproteínas/farmacologia , Humanos , Gotículas Lipídicas , Masculino , Membranas , Proteínas do Leite/farmacologia , Fosfolipídeos/farmacologia , Valores de Referência , Adulto Jovem
13.
Clin Transl Allergy ; 5: 13, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25802736

RESUMO

BACKGROUND: The relative contribution and the relation between individual peanut allergens in peanut allergic responses is still matter of debate. We determined the individual contribution of peanut proteins to B, T cell and allergic effector responses in a mouse model for peanut allergy. METHODS: Mice were immunized and challenged by oral gavage with peanut protein extract or isolated allergens Ara h 1, 2, 3 and 6 followed by assessment of food allergic manifestations. In addition, T cell responses to the individual proteins were measured by an in vitro dendritic cell-T cell assay. RESULTS: Sensitization with the individual peanut proteins elicited IgE responses with specificity to the allergen used as expected. However, cross reactivity among Ara h 1, 2, 3 and 6 was observed. T cell re-stimulations with peanut extract and individual peanut proteins also showed cross reactivity between Ara h 1, 2, 3 and 6. Despite the cross reactivity at the IgE level, only Ara h 2 and 6 were able to elicit mast cell degranulation after an oral challenge. However, after systemic challenge, Ara h 1, 2 and 6 and to lesser extent Ara h 3 were able to elicit anaphylactic responses. CONCLUSIONS: Ara h 1, 2, 3 and 6 sensitize via the intra-gastric route, but differ in their capacity to cause allergic effector responses. Interestingly, extensive cross reactivity at T cell and antibody level is observed among Ara h 1, 2, 3 and 6, which may have important implications for the diagnosis and therapy of peanut allergy. Awareness about the relative contribution of individual peanut allergens and cross reactivity between these allergens is of importance for current research in diagnostics and therapeutics for and the mechanism of peanut allergy.

14.
Clin Transl Allergy ; 5: 8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25774288

RESUMO

BACKGROUND: It is unknown whether food allergy (FA) in an unselected population is comparable to those from an outpatient clinic population. OBJECTIVE: To discover if FA in a random sample from the Dutch community is comparable to that of outpatients. METHODS: This study was part of the Europrevall-project. A random sample of 6600 adults received a questionnaire. Those with symptoms to one of 24 defined priority foods were tested for sIgE. Participants with a positive case history and elevated sIgE were evaluated by double-blind placebo-controlled food challenge (DBPCFC). Outpatients with a suspicion of FA were evaluated by questionnaire, sIgE and DBPCFC. RESULTS: In the community, severe symptoms were reported less often than in outpatients (39.3% vs. 54.3%). Participants in the community were less commonly sensitized to any of the foods. When selecting only those with a probable FA (i.e. symptoms of priority food and elevation of sIgE to the respective food), no major differences were observed with respect to severity, causative foods, sensitization and DBPCFC between the groups. CONCLUSION: In the Netherlands, there are large differences in self-reported FA between community and outpatients. However, Dutch community and outpatients with a probable FA do not differ with respect to severity, causative foods, sensitization and DBPCFC-outcome.

15.
Food Sci Nutr ; 3(1): 81-90, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25648153

RESUMO

Prompted by the accumulating evidence on bioactive moieties of milk-derived peptides, novel methods were applied to compare the peptide composition among commercially available hydrolysate formulations and to determine batch-to-batch variations of protein hydrolysate products. Despite the availability of general methods to measure, for example, the degree of hydrolysis and peptide mass distribution at a high level, the objective of this study was to more qualitatively compare peptide sequences and composition. By a comprehensive approach combining peptidomics technologies and multivariate clustering analyses, the peptide profiles of different hydrolyzed milk protein formulations were compared. Moreover, peptide profiles of various hydrolysate batches that had been produced over a period of 5 years were included. Coupling of identified peptide sequences to the position in their corresponding milk proteins produced numerical datasets that subsequently were utilized for multivariate data analyses. These analyses revealed that batch-to-batch variation in the peptide profiles of a specific extensively hydrolyzed casein preparation was low. Moreover, extensive multivariate evaluations revealed that the peptide profiles of different commercially available hydrolyzed milk protein formulations provided a descriptive and distinct signature. Overall, the described methodology may contribute to the field of peptide research as observed dissimilarities in peptide profiles of similar products may be related to differences in their overall functionality.

16.
Nutr Rev ; 72(6): 377-89, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24828428

RESUMO

Human milk is a rich source of oligosaccharides. Acidic oligosaccharides, such as sialyllactose (SL), contain sialic acid (SA) residues. In human milk, approximately 73% of SA is bound to oligosaccharides, whereas only 3% is present in free form. Oligosaccharides are highly resistant to hydrolysis in the gastrointestinal tract. Only a small portion of the available oligosaccharides in breast milk is absorbed in the neonatal small intestine. SL and sialylated oligosaccharides are thought to have significant health benefits for the neonate, because of their roles in supporting resistance to pathogens, gut maturation, immune function, and cognitive development. The need for SA to allow proper development during the neonatal period is thought to exceed the endogenous synthesis. Therefore, these structures are important nutrients for the neonate. Based on the potential benefits, SL and sialylated oligosaccharides may be interesting components for application in infant nutrition. Once the hurdle of limited availability of these oligosaccharides has been overcome, their functionality can be explored in more detail, and supplementation of infant formula may become feasible.


Assuntos
Dieta , Trato Gastrointestinal/metabolismo , Fenômenos Fisiológicos da Nutrição do Lactente , Lactose/análogos & derivados , Leite Humano/química , Necessidades Nutricionais , Oligossacarídeos/metabolismo , Ácidos Siálicos/metabolismo , Animais , Aleitamento Materno , Suplementos Nutricionais , Humanos , Lactente , Fórmulas Infantis/química , Lactose/metabolismo
17.
Int Arch Allergy Immunol ; 163(4): 292-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24777233

RESUMO

BACKGROUND: Recent studies have indicated that peptides containing T cell epitopes may be used for immunotherapy. While for several cow's milk allergens the T cell epitopes have been described, the T cell epitopes in the major allergen α-lactalbumin (α-LAC) are unknown. Therefore, the aim of this study was to determine the T cell epitopes in α-LAC. METHODS: Nineteen synthetic peptides spanning α-LAC were obtained. Cow's milk-specific T cell lines (TCLs) of 46 subjects were generated and tested for their specificity for α-LAC. The lines responding to α-LAC were subsequently tested to determine their activation in response to the peptides. RESULTS: More than half of the TCLs generated did not respond to α-LAC or lost their responsiveness during subsequent experiments, which indicates that α-LAC has low immunogenicity. Only 8 TCLs recognized 1 or more peptides. The recognition of the peptides was diverse and no major epitopes could be defined. CONCLUSION: The immunogenicity of α-LAC is very low compared to other major allergens in cow's milk. Moreover, there seems to be no dominant epitope present in the protein. Therefore, it seems unlikely that peptides of this protein can be used for immunotherapy.


Assuntos
Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/uso terapêutico , Lactalbumina/imunologia , Hipersensibilidade a Leite/terapia , Alérgenos/imunologia , Sequência de Aminoácidos , Animais , Bovinos , Células Cultivadas , Humanos , Imunoglobulina E/imunologia , Imunoterapia , Leite/imunologia , Dados de Sequência Molecular , Fragmentos de Peptídeos/imunologia , Linfócitos T/imunologia
18.
Food Chem Toxicol ; 65: 364-73, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24412559

RESUMO

SCOPE: Due to the imminent growth of the world population, shortage of protein sources for human consumption will arise in the near future. Alternative and sustainable protein sources (e.g. insects) are being explored for the production of food and feed. In this project, the safety of Yellow mealworms (Tenebrio molitor L.) for human consumption was tested using approaches as advised by the European Food Safety Authority for allergenicity risk assessment. METHODS AND RESULTS: Different Yellow mealworm protein fractions were prepared, characterised, and tested for cross-reactivity using sera from patients with an inhalation or food allergy to biologically related species (House dust mite (HDM) and crustaceans) by immunoblotting and basophil activation. Furthermore, the stability was investigated using an in vitro pepsin digestion test. IgE from HDM- and crustacean allergic patients cross-reacted with Yellow mealworm proteins. This cross-reactivity was functional, as shown by the induction of basophil activation. The major cross-reactive proteins were identified as tropomyosin and arginine kinase, which are well known allergens in arthropods. These proteins were moderately stable in the pepsin stability test. CONCLUSION: Based on these cross-reactivity studies, there is a realistic possibility that HDM- and crustacean allergic patients may react to food containing Yellow mealworm proteins.


Assuntos
Reações Cruzadas , Crustáceos/imunologia , Aditivos Alimentares , Hipersensibilidade/imunologia , Proteínas de Insetos/imunologia , Ácaros/imunologia , Tenebrio/imunologia , Animais , Humanos
19.
Int Arch Allergy Immunol ; 162(4): 335-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24193255

RESUMO

BACKGROUND: Food allergy (FA) affects 2-4% of adults, but only a small percentage visit an outpatient clinic for a thorough evaluation. METHODS: A matched case-control study was used to compare health-related quality of life (HRQL) of the Dutch general population that did not seek medical care for their FA with outpatients who did seek medical care. All participants were diagnosed as food allergic (i.e. with a suggestive history and corresponding positive IgE). HRQL was measured using the Food Allergy Quality of Life Questionnaire--Adult Form (FAQLQ-AF). A food allergy independent measure (FAIM) was used to evaluate the adult's perception of the severity of his/her disease. RESULTS: Total FAQLQ-AF score in individuals who never visited a doctor for their FA was significantly lower than that of patients who sought medical care (2.4 vs. 3.9, p = 0.03), indicating that the former had a better quality of life than patients who did seek medical care. Regarding the different domains of FAQLQ, the score for allergen avoidance and dietary restrictions and the score for emotional impact (EI) was significantly higher in the group that sought medical care (p = 0.02 and 0.03, respectively), indicating the importance of these domains. The FAIM score was significantly higher in the group that sought medical care, indicating that they perceived their FA as more severe. CONCLUSION AND CLINICAL RELEVANCE: Patients who seek medical care for their FA have a more impaired HRQL and perceive their FA as more severe. Food avoidance and issues related to the EI of FA are key areas of intervention aimed at improving HRQL in patients with FA.


Assuntos
Hipersensibilidade Alimentar/tratamento farmacológico , Hipersensibilidade Alimentar/psicologia , Qualidade de Vida , Adulto , Estudos de Casos e Controles , Atenção à Saúde/estatística & dados numéricos , Feminino , Hipersensibilidade Alimentar/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Qualidade de Vida/psicologia , Inquéritos e Questionários , Adulto Jovem
20.
Pediatr Allergy Immunol ; 24(7): 656-64, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24028387

RESUMO

BACKGROUND: Prior exposure to partial whey hydrolysates has been shown to reduce the allergic response to whey in mice. This effect was more pronounced in combination with a diet containing non-digestible oligosaccharides (scGOS/lcFOS/pAOS). It is unknown which fractions/epitopes are responsible for this effect. Therefore, the prophylactic ability of synthetic peptides of ß-lactoglobulin with/without a scGOS/lcFOS/pAOS-containing diet to reduce the allergic response in a mouse model for cow's milk allergy was investigated. METHODS: Of 31 peptides, nine peptides were selected based on human T cell data. Mice were pre-treated orally with three peptide mixtures or single peptides for six consecutive days. During this period, they received a control or scGOS/lcFOS/pAOS-containing diet. Subsequently, mice were orally sensitized to whey and received an intradermal and oral challenge. After sacrifice, serum and mesenteric lymph nodes (MLN) were collected for further analysis. RESULTS: Prior exposure to peptide mixtures 1 and 3 significantly reduced the acute allergic skin response to whey. Mixture 2 showed no effect. An additive effect of the scGOS/lcFOS/pAOS-containing diet was only observed for mixture 1. Of the peptides in mixture 1, one peptide (LLDAQSAPLRVYVEELKP) showed the strongest effect on the acute allergic skin response. This peptide also tended to decrease whey-specific antibody levels and to increase the percentages of CD11b+CD103+ dendritic cells and CD25+Foxp3+ T cells in the MLN. CONCLUSIONS: Prior exposure to specific peptides of ß-lactoglobulin reduces the allergic response to whey, which may involve regulatory dendritic and T cells. Combining peptides with a sGOS/lcFOS/pAOS-containing diet enhances this effect.


Assuntos
Alérgenos/administração & dosagem , Lactoglobulinas/administração & dosagem , Hipersensibilidade a Leite/terapia , Oligossacarídeos/administração & dosagem , Fragmentos de Peptídeos/administração & dosagem , Linfócitos T/imunologia , Administração Oral , Alérgenos/imunologia , Sequência de Aminoácidos , Animais , Bovinos , Linhagem Celular , Proliferação de Células , Criança , Modelos Animais de Doenças , Feminino , Humanos , Lactoglobulinas/imunologia , Camundongos , Camundongos Endogâmicos C3H , Hipersensibilidade a Leite/imunologia , Dados de Sequência Molecular , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/imunologia
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