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1.
Proc Natl Acad Sci U S A ; 120(39): e2303455120, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37722054

RESUMEN

Cows produce antibodies with a disulfide-bonded antigen-binding domain embedded within ultralong heavy chain third complementarity determining regions. This "knob" domain is analogous to natural cysteine-rich peptides such as knottins in that it is small and stable but can accommodate diverse loops and disulfide bonding patterns. We immunized cattle with SARS-CoV-2 spike and found ultralong CDR H3 antibodies that could neutralize several viral variants at picomolar IC50 potencies in vitro and could protect from disease in vivo. The independent CDR H3 peptide knobs were expressed and maintained the properties of the parent antibodies. The knob interaction with SARS-CoV-2 spike was revealed by electron microscopy, X-ray crystallography, NMR spectroscopy, and mass spectrometry and established ultralong CDR H3-derived knobs as the smallest known recombinant independent antigen-binding fragment. Unlike other vertebrate antibody fragments, these knobs are not reliant on the immunoglobulin domain and have potential as a new class of therapeutics.


Asunto(s)
COVID-19 , SARS-CoV-2 , Femenino , Animales , Bovinos , Anticuerpos , Fragmentos Fab de Inmunoglobulinas/genética , Disulfuros
2.
FASEB J ; 38(20): e70116, 2024 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-39425543

RESUMEN

Embryo survival and pre-implantation development depend on uterine luminal fluid, which is believed to play a role in early embryonic death and infertility in cows. Extracellular vesicles (EVs) in the uterine luminal fluid contain microRNAs (miRNAs), crucial mediators of intercellular communication. miRNAs regulate conceptus-maternal interactions and participate in embryonic development by suppressing gene expression. Therefore, we hypothesized that miRNAs in the intrauterine EVs of low-fertility cows would hinder embryonic survival and development. EVs were collected from the bovine uterine luminal fluid of both normal- and low-fertility cows 7 days post-estrus. Small RNA-sequencing analysis of miRNAs isolated from these EVs identified eight miRNAs that were highly expressed in normal-fertility cows (normal-fertility miRNAs) and eight with elevated expression in low-fertility cows (low-fertility miRNAs). These two sets of miRNAs were transfected into hatched blastocysts via lipofection. RNA-seq following lipofection with low-fertility miRNAs identified 424 differentially expressed genes (DEGs) relative to the control; in contrast, following lipofection with normal-fertility miRNAs, seven DEGs were identified. Pathway analysis of the DEGs identified following lipofection with low-fertility miRNAs revealed substantial enrichment of mitogen-activated protein kinase (MAPK) signaling. Expression of activator protein 1 (AP1) and interferon-tau (IFNT) mRNA was significantly lower in the low-fertility miRNA transfection group than in the control. IFNT is essential for maternal pregnancy recognition. Therefore, miRNAs in intrauterine EVs from low-fertility cows at 7 days post-estrus may inhibit embryo development and suppress IFNT expression by altering MAPK signaling.


Asunto(s)
Vesículas Extracelulares , MicroARNs , Animales , Bovinos , MicroARNs/genética , MicroARNs/metabolismo , Femenino , Vesículas Extracelulares/metabolismo , Embarazo , Desarrollo Embrionario/genética , Regulación del Desarrollo de la Expresión Génica , Blastocisto/metabolismo , Útero/metabolismo , Fertilidad/genética , Proteínas Gestacionales/genética , Proteínas Gestacionales/metabolismo , Embrión de Mamíferos/metabolismo
3.
BMC Biol ; 22(1): 65, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38486242

RESUMEN

BACKGROUND: DNA methylation has been documented to play vital roles in diseases and biological processes. In bovine, little is known about the regulatory roles of DNA methylation alterations on production and health traits, including mastitis. RESULTS: Here, we employed whole-genome DNA methylation sequencing to profile the DNA methylation patterns of milk somatic cells from sixteen cows with naturally occurring Staphylococcus aureus (S. aureus) subclinical mastitis and ten healthy control cows. We observed abundant DNA methylation alterations, including 3,356,456 differentially methylated cytosines and 153,783 differential methylation haplotype blocks (dMHBs). The DNA methylation in regulatory regions, including promoters, first exons and first introns, showed global significant negative correlations with gene expression status. We identified 6435 dMHBs located in the regulatory regions of differentially expressed genes and significantly correlated with their corresponding genes, revealing their potential effects on transcriptional activities. Genes harboring DNA methylation alterations were significantly enriched in multiple immune- and disease-related pathways, suggesting the involvement of DNA methylation in regulating host responses to S. aureus subclinical mastitis. In addition, we found nine discriminant signatures (differentiates cows with S. aureus subclinical mastitis from healthy cows) representing the majority of the DNA methylation variations related to S. aureus subclinical mastitis. Validation of seven dMHBs in 200 cows indicated significant associations with mammary gland health (SCC and SCS) and milk production performance (milk yield). CONCLUSIONS: In conclusion, our findings revealed abundant DNA methylation alterations in milk somatic cells that may be involved in regulating mammary gland defense against S. aureus infection. Particularly noteworthy is the identification of seven dMHBs showing significant associations with mammary gland health, underscoring their potential as promising epigenetic biomarkers. Overall, our findings on DNA methylation alterations offer novel insights into the regulatory mechanisms of bovine subclinical mastitis, providing further avenues for the development of effective control measures.


Asunto(s)
Mastitis Bovina , Infecciones Estafilocócicas , Bovinos , Animales , Femenino , Humanos , Staphylococcus aureus , Metilación de ADN , Mastitis Bovina/genética , Mastitis Bovina/metabolismo , Haplotipos , Infecciones Estafilocócicas/genética , Infecciones Estafilocócicas/veterinaria
4.
BMC Genomics ; 25(1): 632, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38914933

RESUMEN

BACKGROUND: Although, oocytes from prepubertal donors are known to be less developmentally competent than those from adult donors it does not restrain their ability to produce full-term pregnancies. The transcriptomic profile of embryos could be used as a predictor for embryo's individual developmental competence. The aim of the study was to compare transcriptomic profile of blastocysts derived from prepubertal and pubertal heifers oocytes. Bovine cumulus-oocyte complexes (COCs) were obtained by ovum pick- up method from prepubertal and pubertal heifers. After in vitro maturation COCs were fertilized and cultured to the blastocyst stage. Total RNA was isolated from both groups of blastocysts and RNA-seq was performed. Gene ontology analysis was performed by DAVID (Database for Annotation, Visualization and Integrated Discovery). RESULTS: A higher average blastocyst rate was obtained in the pubertal than in the pre-pubertal group. There were no differences in the quality of blastocysts between the examined groups. We identified 436 differentially expressed genes (DEGs) between blastocysts derived from researched groups, of which 247 DEGs were downregulated in blastocysts derived from pubertal compared to prepubertal heifers oocytes, and 189 DEGs were upregulated. The genes involved in mitochondrial function, including oxidative phosphorylation (OXPHOS) were found to be different in studied groups using Kyoto Encyclopedia of Genes (KEGG) pathway analysis and 8 of those DEGs were upregulated and 1 was downregulated in blastocysts derived from pubertal compared to prepubertal heifers oocytes. DEGs associated with mitochondrial function were found: ATP synthases (ATP5MF-ATP synthase membrane subunit f, ATP5PD- ATP synthase peripheral stalk subunit d, ATP12A- ATPase H+/K + transporting non-gastric alpha2 subunit), NADH dehydrogenases (NDUFS3- NADH: ubiquinone oxidoreductase subunit core subunit S3, NDUFA13- NADH: ubiquinone oxidoreductase subunit A13, NDUFA3- NADH: ubiquinone oxidoreductase subunit A3), cytochrome c oxidase (COX17), cytochrome c somatic (CYCS) and ubiquinol cytochrome c reductase core protein 1 (UQCRC1). We found lower number of apoptotic cells in blastocysts derived from oocytes collected from prepubertal than those obtained from pubertal donors. CONCLUSIONS: Despite decreased expression of genes associated with OXPHOS pathway in blastocysts from prepubertal heifers oocytes, the increased level of ATP12A together with the lower number of apoptotic cells in these blastocysts might support their survival after transfer.


Asunto(s)
Blastocisto , Perfilación de la Expresión Génica , Fosforilación Oxidativa , Animales , Bovinos , Femenino , Blastocisto/metabolismo , Transcriptoma , Maduración Sexual/genética , Oocitos/metabolismo , Regulación del Desarrollo de la Expresión Génica , Fertilización In Vitro/veterinaria
5.
BMC Genomics ; 25(1): 882, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39300336

RESUMEN

MicroRNA (miRNA) is a type of endogenous non-coding small RNA, which is abundant in living organisms. miRNAs play an important role in regulating gene expression and myriad cellular processes by binding to target messenger RNAs through complementary base pairing, and cross-species regulation mammalian cells by plant-derived xeno-miRNAs has been described. Here, we examined the miRNA species in two alfalfa (Medicago sativa, lucerne) cultivars commonly grown in Ningxia, China: cv. Zhongmu 1 and cv. Xinyan 52. Both cultivars have good salt and drought resistance. We found that the miRNA profiles were similar between the cultivars, with a slightly higher number of miRNAs present in the newer cv. Xinyan 52, which may contribute to its improved salt and drought tolerance. miRNAs were stable during drying, and some miRNAs were increased in dry versus fresh alfalfa, suggesting some miRNAs may be upregulated during drying. Alfalfa-derived miRNAs could be detected in exosomes from serum and whey collected from dairy cows, confirming the ability of the exogenous miRNAs (xeno-miRNAs) to enter the circulation and reach the mammary epithelium. In vitro studies confirmed that overexpression of mtr-miR156a could downregulate expression of Phosphatase 2 Regulatory Subunit B'gamma ( PPP2R5D) and Phosphoinositide-3-kinase Regulatory Subunit 2 (PIK3R2). Overexpression of mtr-miR156a also modulated PI3K-AKT-mTOR signaling as well as the casein content of milk produced by bovine mammary epithelial cells. Based on the known roles of PPP2R5D and PIK3R2 in regulating the PI3K-AKT-mTOR pathway as well as the effect of PI3K-AKT-mTOR on milk protein content, our findings implicate alfalfa-derived miR156a as a new cross-species regulator of milk quality in dairy cows.


Asunto(s)
Exosomas , Medicago sativa , MicroARNs , Leche , Animales , Bovinos , MicroARNs/genética , MicroARNs/metabolismo , Leche/metabolismo , Leche/química , Femenino , Exosomas/metabolismo , Exosomas/genética , Medicago sativa/genética , Medicago sativa/metabolismo , Proteínas de la Leche/metabolismo , Proteínas de la Leche/genética , Células Epiteliales/metabolismo , Transducción de Señal
6.
J Gen Virol ; 105(6)2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38922678

RESUMEN

Highly pathogenic avian influenza (HPAI) H5N1 viruses are responsible for disease outbreaks in wild birds and poultry, resulting in devastating losses to the poultry sector. Since 2020, an increasing number of outbreaks of HPAI H5N1 was seen in wild birds. Infections in mammals have become more common, in most cases in carnivores after direct contact with infected birds. Although ruminants were previously not considered a host species for HPAI viruses, in March 2024 multiple outbreaks of HPAI H5N1 were detected in goats and cattle in the United States. Here, we have used primary bronchus-derived well-differentiated bovine airway epithelial cells (WD-AECs) cultured at air-liquid interface to assess the susceptibility and permissiveness of bovine epithelial cells to infection with European H5N1 virus isolates. We inoculated bovine WD-AECs with three low-passage HPAI clade 2.3.4.4b H5N1 virus isolates and detected rapid increases in viral genome loads and infectious virus during the first 24 h post-inoculation, without substantial cytopathogenic effects. Three days post-inoculation infected cells were still detectable by immunofluorescent staining. These data indicate that multiple lineages of HPAI H5N1 may have the propensity to infect the respiratory tract of cattle and support extension of avian influenza surveillance efforts to ruminants. Furthermore, this study underscores the benefit of WD-AEC cultures for pandemic preparedness by providing a rapid and animal-free assessment of the host range of an emerging pathogen.


Asunto(s)
Células Epiteliales , Subtipo H5N1 del Virus de la Influenza A , Replicación Viral , Animales , Bovinos , Células Epiteliales/virología , Subtipo H5N1 del Virus de la Influenza A/genética , Subtipo H5N1 del Virus de la Influenza A/fisiología , Subtipo H5N1 del Virus de la Influenza A/aislamiento & purificación , Células Cultivadas
7.
Mol Genet Genomics ; 299(1): 40, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38546894

RESUMEN

Genomic imprinting is an epigenetic regulation mechanism in mammals resulting in the parentally dependent monoallelic expression of genes. Imprinting disorders in humans are associated with several congenital syndromes and cancers and remain the focus of many medical studies. Cattle is a better model organism for investigating human embryo development than mice. Imprinted genes usually cluster on chromosomes and are regulated by different methylation regions (DMRs) located in imprinting control regions that control gene expression in cis. There is an imprinted locus on human chromosome 16q24.1 associated with congenital lethal developmental lung disease in newborns. However, genomic imprinting on bovine chromosome 18, which is homologous with human chromosome 16 has not been systematically studied. The aim of this study was to analyze the allelic expressions of eight genes (CDH13, ATP2C2, TLDC1, COTL1, CRISPLD2, ZDHHC7, KIAA0513, and GSE1) on bovine chromosome 18 and to search the DMRs associated gene allelic expression. Three transcript variants of the ZDHHC7 gene (X1, X2, and X5) showed maternal imprinting in bovine placentas. In addition, the monoallelic expression of X2 and X5 was tissue-specific. Five transcripts of the KIAA0513 gene showed tissue- and isoform-specific monoallelic expression. The CDH13, ATP2C2, and TLDC1 genes exhibited tissue-specific imprinting, however, COTL1, CRISLPLD2, and GSE1 escaped imprinting. Four DMRs, established after fertilization, were found in this region. Two DMRs were located between the ZDHHC7 and KIAA0513 genes, and two were in exon 1 of the CDH13 and ATP2C2 genes, respectively. The results from this study support future studies on the molecular mechanism to regulate the imprinting of candidate genes on bovine chromosome 18.


Asunto(s)
Metilación de ADN , Epigénesis Genética , Recién Nacido , Embarazo , Femenino , Humanos , Bovinos/genética , Animales , Ratones , Metilación de ADN/genética , Cromosomas Humanos Par 18 , Impresión Genómica/genética , Cromosomas , Mamíferos/genética , Proteínas del Tejido Nervioso/genética
8.
Biol Reprod ; 111(2): 332-350, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38704744

RESUMEN

Cows with metritis (uterine disease) during the first 1 to 2 weeks postpartum have lower pregnancy rates when inseminated later postpartum (typically >10 weeks). We hypothesized that metritis and the disease-associated uterine microbiome have a long-term effect on endometrial gene expression. Changes in gene expression may inform a mechanism through which disease lowers pregnancy rates. A total of 20 cows were enrolled at 1 to 2 weeks postpartum to either metritis (clinical disease; n = 10) or healthy (control; n = 10) groups and randomly assigned to be slaughtered at approximately 80 and 165 dpp (mid-lactation). The microbiome of the reproductive tract was sampled to confirm the presence of pathogens that are typical of metritis. In addition to the original clinical diagnosis, study cows were retrospectively assigned to uterine-disease and control groups based on the composition of their microbiome. There was no effect of early postpartum uterine disease on the uterine microbiome at mid-lactation (time of slaughter). Nonetheless, early postpartum metritis and the disease microbiome were associated with a large number of differentially-expressed genes at mid-lactation primarily in the caruncular compared with the inter-caruncular endometrium. Gene enrichment analysis identified oxidative phosphorylation as the primary pathway increased in caruncular endometrium of diseased cows whereas growth factor signaling pathways were reduced. The current study demonstrated that metritis and a uterine disease microbiome leave a sustained imprint on gene expression in the caruncular endometrium that may explain lower fertility in cows with postpartum uterine disease.


Asunto(s)
Enfermedades de los Bovinos , Endometritis , Endometrio , Microbiota , Enfermedades Uterinas , Femenino , Animales , Bovinos , Enfermedades de los Bovinos/microbiología , Endometrio/microbiología , Endometrio/metabolismo , Enfermedades Uterinas/veterinaria , Enfermedades Uterinas/microbiología , Endometritis/microbiología , Endometritis/veterinaria , Periodo Posparto , Embarazo
9.
Biol Reprod ; 111(1): 43-53, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38519105

RESUMEN

A high incidence of pregnancy failures occurs in cattle during the second week of pregnancy as blastocysts transition into an elongated conceptus. This work explored whether interleukin-6 supplementation during in vitro embryo production would improve subsequent conceptus development. Bovine embryos were treated with 0 or 100 ng/mL recombinant bovine interleukin-6 beginning on day 5 post-fertilization. At day 7.5 post-fertilization, blastocysts were transferred into estrus synchronized beef cows (n = 5 recipients/treatment, 10 embryos/recipient). Seven days after transfer (day 14.5), cows were euthanized to harvest reproductive tracts and collect conceptuses. Individual conceptus lengths and stages were recorded before processing for RNA sequencing. Increases in conceptus recovery, length, and the proportion of tubular and filamentous conceptuses were detected in conceptuses derived from interleukin-6-treated embryos. The interleukin-6 treatment generated 591 differentially expressed genes in conceptuses (n = 9-10/treatment). Gene ontology enrichment analyses revealed changes in transcriptional regulation, DNA-binding, and antiviral actions. Only a few differentially expressed genes were associated with extraembryonic development, but several differentially expressed genes were associated with embryonic regulation of transcription, mesoderm and ectoderm development, organogenesis, limb formation, and somatogenesis. To conclude, this work provides evidence that interleukin-6 treatment before embryo transfer promotes pre-implantation conceptus development and gene expression in ways that resemble the generation of a robust conceptus containing favorable abilities to survive this critical period of pregnancy.


Asunto(s)
Desarrollo Embrionario , Interleucina-6 , Transcriptoma , Animales , Bovinos , Interleucina-6/genética , Interleucina-6/metabolismo , Interleucina-6/farmacología , Desarrollo Embrionario/efectos de los fármacos , Femenino , Transcriptoma/efectos de los fármacos , Técnicas de Cultivo de Embriones/veterinaria , Embarazo , Fertilización In Vitro/veterinaria , Blastocisto/efectos de los fármacos , Blastocisto/metabolismo , Transferencia de Embrión/veterinaria , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Embrión de Mamíferos/efectos de los fármacos
10.
BMC Microbiol ; 24(1): 251, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38977975

RESUMEN

OBJECTIVES: To study the effect of agitation and temperature on biofilm formation (cell aggregates embedded within a self-produced matrix) by pathogenic bacteria isolated from Raw cow milk (RCM). METHODS: A 40 RCM samples were gathered from eight dairy farms in Riyadh, Saudi Arabia. After bacterial culturing and isolation, gram staining was performed, and all pathogenic, identified using standard criteria established by Food Standards Australia New Zealand (FSANZ), and non-pathogenic bacteria were identified using VITEK-2 and biochemical assays. To evaluate the effects of temperature and agitation on biofilm formation, isolated pathogenic bacteria were incubated for 24 h under the following conditions: 4 °C with no agitation (0 rpm), 15 °C with no agitation, 30 °C with no agitation, 30 °C with 60 rpm agitation, and 30 °C with 120 rpm agitation. Then, biofilms were measured using a crystal violet assay. RESULTS: Of the eight farm sites, three exhibited non-pathogenic bacterial contamination in their raw milk samples. Of the total of 40 raw milk samples, 15/40 (37.5%; from five farms) were contaminated with pathogenic bacteria. Overall, 346 bacteria were isolated from the 40 samples, with 329/346 (95.1%) considered as non-pathogenic and 17/346 (4.9%) as pathogenic. Most of the isolated pathogenic bacteria exhibited a significant (p < 0.01) increase in biofilm formation when grown at 30 °C compared to 4 °C and when grown with 120 rpm agitation compared to 0 rpm. CONCLUSION: Herein, we highlight the practices of consumers in terms of transporting and storing (temperature and agitation) can significantly impact on the growth of pathogens and biofilm formation in RCM.


Asunto(s)
Bacterias , Biopelículas , Leche , Temperatura , Animales , Biopelículas/crecimiento & desarrollo , Leche/microbiología , Bovinos , Bacterias/aislamiento & purificación , Bacterias/clasificación , Bacterias/crecimiento & desarrollo , Arabia Saudita , Microbiología de Alimentos , Fenómenos Fisiológicos Bacterianos
11.
Microb Pathog ; 197: 107082, 2024 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-39461446

RESUMEN

MicroRNAs (miRNAs) are involved in various biological processes where they regulate the expression of mRNAs. Bovine mammary epithelial cells (bMECs) are functional cells that mediate mammary inflammatory immunity. Although numerous miRNAs regulate the function of bMECs, the role of miR-19b in bMECs has not been reported. In this study, the transcriptome of miR-19b overexpressed bMECs was analyzed by RNA-seq. Additionally, the differentially expressed genes (DEGs) were analyzed to establish the role of miR-19b in bMECs. The results revealed 269 DEGs between the miR-19b overexpression group and the negative control, including 199 up-regulated and 70 down-regulated genes. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses revealed that the DEGs regulated immune and inflammatory responses through Staphylococcus aureus (S. aureus) infection and phosphatidylinositol 3-kinase (PI3K)-Akt signaling pathway. In addition, the expression of miR-19b was significantly upregulated in lipophosphoric acid (LTA)-induced bMECs, and overexpression of miR-19b negatively regulated the expression of inflammatory cytokines IL-1ß and IL-6, thereby alleviating the inflammatory response of LTA-induced bMECs. Based on the above results, we speculate that miR-19b may inhibit in dairy cow mammary inflammation caused by S. aureus, and this process may be mediated through the regulation of relevant gene expression and signaling pathways. The findings from this study provide a new reference for analyzing the molecular regulation of miR-19b in bMECs.

12.
Allergy ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38899450

RESUMEN

BACKGROUND: Cow's milk allergy (CMA) overdiagnosis in young children appears to be increasing and has not been well characterised. We used a clinical trial population to characterise CMA overdiagnosis and identify individual-level and primary care practice-level risk factors. METHODS: We analysed data from 1394 children born in England in 2014-2016 (BEEP trial, ISRCTN21528841). Participants underwent formal CMA diagnosis at ≤2 years. CMA overdiagnosis was defined in three separate ways: parent-reported milk reaction; primary care record of milk hypersensitivity symptoms; and primary care record of low-allergy formula prescription. RESULTS: CMA was formally diagnosed in 19 (1.4%) participants. CMA overdiagnosis was common: 16.1% had parent-reported cow's milk hypersensitivity, 11.3% primary care recorded milk hypersensitivity and 8.7% had low-allergy formula prescription. Symptoms attributed to cow's milk hypersensitivity in participants without CMA were commonly gastrointestinal and reported from a median age of 49 days. Low-allergy formula prescriptions in participants without CMA lasted a median of 10 months (interquartile range 1, 16); the estimated volume consumed was a median of 272 litres (26, 448). Risk factors for CMA overdiagnosis were high practice-based low-allergy formula prescribing in the previous year and maternal report of antibiotic prescription during pregnancy. Exclusive formula feeding from birth was associated with increased low-allergy formula prescription. There was no evidence that practice prescribing of paediatric adrenaline auto-injectors or anti-reflux medications, or maternal features such as anxiety, age, parity and socioeconomic status were associated with CMA overdiagnosis. CONCLUSION: CMA overdiagnosis is common in early infancy. Risk factors include high primary care practice-based low-allergy formula prescribing and maternal report of antibiotic prescription during pregnancy.

13.
Allergy ; 79(4): 949-963, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38193259

RESUMEN

BACKGROUND: IgE-mediated cow's milk allergy (IgE-CMA) is one of the first allergies to arise in early childhood and may result from exposure to various milk allergens, of which ß-lactoglobulin (BLG) and casein are the most important. Understanding the underlying mechanisms behind IgE-CMA is imperative for the discovery of novel biomarkers and the design of innovative treatment and prevention strategies. METHODS: We report a longitudinal in vivo murine model, in which two mice strains (BALB/c and C57Bl/6) were sensitized to BLG using either cholera toxin or an oil emulsion (n = 6 per group). After sensitization, mice were challenged orally, their clinical signs monitored, antibody (IgE and IgG1) and cytokine levels (IL-4 and IFN-γ) measured, and fecal samples subjected to metabolomics. The results of the murine models were further extrapolated to fecal microbiome-metabolome data from our population of IgE-CMA (n = 22) and healthy (n = 23) children (Trial: NCT04249973), on which polar metabolomics, lipidomics and 16S rRNA metasequencing were performed. In vitro gastrointestinal digestions and multi-omics corroborated the microbial origin of proposed metabolic changes. RESULTS: During mice sensitization, we observed multiple microbially derived metabolic alterations, most importantly bile acid, energy and tryptophan metabolites, that preceded allergic inflammation. We confirmed microbial dysbiosis, and its associated effect on metabolic alterations in our patient cohort, through in vitro digestions and multi-omics, which was accompanied by metabolic signatures of low-grade inflammation. CONCLUSION: Our results indicate that gut dysbiosis precedes allergic inflammation and nurtures a chronic low-grade inflammation in children on elimination diets, opening important new opportunities for future prevention and treatment strategies.


Asunto(s)
Microbiota , Hipersensibilidad a la Leche , Humanos , Niño , Preescolar , Bovinos , Femenino , Ratones , Animales , Disbiosis , ARN Ribosómico 16S , Inflamación , Alérgenos , Lactoglobulinas , Inmunoglobulina E , Metaboloma
14.
Allergy ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38989779

RESUMEN

BACKGROUND: Antigen-specific memory B cells play a key role in the induction of desensitization and remission to food allergens in oral immunotherapy and in the development of natural tolerance (NT). Here, we characterized milk allergen Bos d 9-specific B cells in oral allergen-specific immunotherapy (OIT) and in children spontaneously outgrowing cow's milk allergy (CMA) due to NT. METHODS: Samples from children with CMA who received oral OIT (before, during, and after), children who naturally outgrew CMA (NT), and healthy individuals were received from Stanford biobank. Bos d 9-specific B cells were isolated by flow cytometry and RNA-sequencing was performed. Protein profile of Bos d 9-specific B cells was analyzed by proximity extension assay. RESULTS: Increased frequencies of circulating milk allergen Bos d 9-specific B cells were observed after OIT and NT. Milk-desensitized subjects showed the partial acquisition of phenotypic features of remission, suggesting that desensitization is an earlier stage of remission. Within these most significantly expressed genes, IL10RA and TGFB3 were highly expressed in desensitized OIT patients. In both the remission and desensitized groups, B cell activation-, Breg cells-, BCR-signaling-, and differentiation-related genes were upregulated. In NT, pathways associated with innate immunity characteristics, development of marginal zone B cells, and a more established suppressor function of B cells prevail that may play a role in long-term tolerance. The analyses of immunoglobulin heavy chain genes in specific B cells demonstrated that IgG2 in desensitization, IgG1, IgA1, IgA2, IgG4, and IgD in remission, and IgD in NT were predominating. Secreted proteins from allergen-specific B cells revealed higher levels of regulatory cytokines, IL-10, and TGF-ß after OIT and NT. CONCLUSION: Allergen-specific B cells are essential elements in regulating food allergy towards remission in OIT-received and naturally resolved individuals.

15.
J Nutr ; 154(8): 2493-2500, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38906178

RESUMEN

BACKGROUND: The Trial to Reduce IDDM in the Genetically at Risk (TRIGR) (NCT00179777) found no difference type 1 diabetes risk between hydrolyzed and regular infant formula. However, cow milk consumption during childhood is consistently linked to type 1 diabetes risk in prospective cohort studies. OBJECTIVES: Our primary aim was to study whether humoral immune responses to cow milk and cow milk consumption are associated with type 1 diabetes in TRIGR children. METHODS: TRIGR comprised 2159 children with genetic susceptibility to type 1 diabetes born between 2002 and 2007 in 15 countries. Children were randomly assigned into groups receiving extensively hydrolyzed casein or a regular cow milk formula and followed up until age 10 y. Type 1 diabetes-related autoantibodies and antibodies to cow milk proteins were analyzed. Infant formula intake was measured by structured dietary interviews and milk consumption with a food frequency questionnaire. Associations of milk antibodies and milk consumption with risk to develop type 1 diabetes were analyzed using Cox survival model. RESULTS: Cow milk antibody concentrations both in cord blood [hazards ratio (HR) for islet autoimmunity: 1.30; 95% CI: 1.05, 1.61; HR for type 1 diabetes: 1.32; 95% CI: 1.02, 1.71] and longitudinally from birth to 3 years (HR for islet autoimmunity: 1.39; 95% CI: 1.07, 1.81; HR for type 1 diabetes: 1.43; 95% CI: 1.04, 1.96) were associated with increased risk of developing type 1 diabetes. The amount of regular infant formula was associated with reduced islet autoimmunity risk in the regular infant formula group (HR: 0.92; 95% CI: 0.85, 0.99). Furthermore, frequent liquid milk consumption after infancy was associated with increased risk of islet autoimmunity or type 1 diabetes. CONCLUSIONS: Elevated cow milk antibody concentrations and high consumption of liquid milk after infancy are related to type 1 diabetes development in children with an increased genetic susceptibility to type 1 diabetes. Enhanced antibody concentrations to cow milk may provide a biomarker of immune system prone to develop islet autoimmunity. This trial was registered at clinicaltrials.gov as NCT00179777.


Asunto(s)
Autoinmunidad , Diabetes Mellitus Tipo 1 , Inmunoglobulina G , Fórmulas Infantiles , Islotes Pancreáticos , Proteínas de la Leche , Leche , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/inmunología , Humanos , Animales , Lactante , Femenino , Masculino , Inmunoglobulina G/sangre , Islotes Pancreáticos/inmunología , Bovinos , Proteínas de la Leche/inmunología , Preescolar , Autoanticuerpos/sangre , Predisposición Genética a la Enfermedad , Factores de Riesgo , Niño , Dieta , Estudios de Seguimiento , Caseínas/inmunología
16.
Int Arch Allergy Immunol ; 185(6): 536-544, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38447540

RESUMEN

INTRODUCTION: The primary dietary approach for managing cow's milk allergy (CMA) is the elimination diet. We aimed to compare the growth patterns of children with CMA during and after the elimination diet with healthy peers and identify influencing factors. METHODS: We compared 74 CMA children with age-matched healthy peers. Anthropometric data were collected during the third month of cow's milk elimination (CME) diet (T1), 3 months after diet cessation (T2), and after ≥3 months of normal diet (T3). Control group measurements coincided. Nutrient intake was assessed by a 3-day record, and patient laboratory results were noted at T3. RESULTS: CMA children had consistently lower weight-for-age (WFA) and height-for-age (HFA) z-scores than controls. WtHt z-score of patients was lower than those of the healthy group at T2. HC z-scores of patients were lower than those of the healthy group at T0, T2, and T3. At T3, the HFA z-score of the CME group demonstrated a negative correlation with the duration of the elimination diet (p = 0.045). Inadequate intake of energy, vitamins A, E, B1, B6, C, folic acid, magnesium, and iron was significantly higher in CMA children (p < 0.05). T3 WFA z-score correlated positively with fiber, vitamin B1, magnesium, and iron intake (p < 0.05). T3 WtHt showed a positive moderate correlation with energy, protein, vitamin E, vitamin B1, vitamin B2, vitamin B6, calcium, magnesium, phosphor, iron intake (p < 0.05). CONCLUSIONS: Post-elimination diet, children with CMA need sustained monitoring and potentially micronutrient supplementation to match healthy peers' growth.


Asunto(s)
Hipersensibilidad a la Leche , Humanos , Hipersensibilidad a la Leche/dietoterapia , Hipersensibilidad a la Leche/inmunología , Femenino , Masculino , Preescolar , Animales , Niño , Leche/inmunología , Bovinos , Estudios Longitudinales , Lactante , Dieta , Dieta de Eliminación
17.
Int Arch Allergy Immunol ; 185(4): 334-342, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38194937

RESUMEN

INTRODUCTION: Food protein-induced enterocolitis syndrome (FPIES) is a form of non-IgE-mediated gastrointestinal food allergy. FPIES is considered a rare food allergy disorder and is often under-recognized. Therefore, clinicians should have a better understanding of its manifestations and maintain a high index of suspicion for a correct diagnosis. To this end, information about differences in the characteristics of caregiver-reported and physician-diagnosed FPIES is important. METHODS: The present, national, multicentric, prospective birth cohort study, called the Japan Environment and Children's Study (JECS), enrolled a general population of 104,062 fetal records. The characteristics of FPIES in 1.5-year-old children were categorized as cases reported by caregivers or as those diagnosed by a physician using questionnaire data. RESULTS: The prevalence of caregiver-reported and physician-diagnosed FPIES cases was 0.69% and 0.06%, respectively. Among the former, the most common causative food was hen's egg (HE), and the second most common causative food was cow's milk (CM) (51.0% and 17.1% of patients responded to HE and CM, which accounted for 46% and 15% of all the causative foods, respectively). Conversely, among the physician-diagnosed cases, the most common causative food was CM followed by HE (57.7% and 36.5% of patients responded to CM and HE, which accounted for 46% and 29% of all the causative foods, respectively). CM accounted for a significantly higher proportion of causative foods in physician-diagnosed FPIES while HE accounted for a significantly higher proportion of caregiver-reported FPIES (p < 0.05). CONCLUSION: A discrepancy was found in reports of the most common causative food between caregiver-reported and physician-diagnosed cases of FPIES.


Asunto(s)
Enterocolitis , Hipersensibilidad a los Alimentos , Bovinos , Humanos , Femenino , Animales , Lactante , Preescolar , Cuidadores , Estudios de Cohortes , Estudios Prospectivos , Pollos , Japón/epidemiología , Hipersensibilidad a los Alimentos/diagnóstico , Hipersensibilidad a los Alimentos/epidemiología , Hipersensibilidad a los Alimentos/complicaciones , Enterocolitis/diagnóstico , Enterocolitis/epidemiología , Enterocolitis/etiología , Alérgenos , Proteínas en la Dieta/efectos adversos
18.
Pediatr Allergy Immunol ; 35(7): e14202, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39022888

RESUMEN

BACKGROUND: The impact of alternative milk substitutes on the nutritional status of children with cow's milk allergy (CMA), the prevailing cause of food allergies, is unresolved. METHODS: A cross-sectional study was performed in children older than 2 years with IgE-mediated CMA. Patients' clinical characteristics, anthropometric measurements, dietary intake (by 3-day food diary), and biochemical markers of nutritional status were assessed. RESULTS: One hundred two children with CMA (68.6% boys; median age, 3.7 years; 51% multiple food allergies) were evaluated. 44.1% of the children consumed plant-based beverages (PBB), 19.6% therapeutic formula and 36.3% did not consume any milk substitutes. In all age groups, dietary calcium, riboflavin, and vitamin D intake of those who did not use milk substitutes were lower than those who consumed formula or PBB (p < .01). Also in the 2-3 years old age group, dietary zinc (p = .011) and iron intake (p = .004) of the formula-fed group was higher. Formula-fed patients had higher levels of 25-OH vitamin D (µg/L) and serum vitamin B12 (ng/L) than PBB-fed patients (respectively; p < .001, p = .005) and those who did not consume any milk substitute (p < .001). Patients of all ages who did not utilize a milk substitute failed to obtain an adequate amount of dietary calcium. CONCLUSION: The use of milk substitutes positively affects dietary calcium, riboflavin, and vitamin D intake in CMA, but their contribution is variable. Those who do not use milk substitutes are at greater risk inadequate of dietary calcium intake. Personalized nutritional advice, given the clinical diversity and the impact of individual differences, is required.


Asunto(s)
Hipersensibilidad a la Leche , Sustitutos de la Leche , Estado Nutricional , Vitamina D , Humanos , Hipersensibilidad a la Leche/dietoterapia , Hipersensibilidad a la Leche/inmunología , Femenino , Estudios Transversales , Masculino , Preescolar , Niño , Animales , Vitamina D/sangre , Calcio de la Dieta/administración & dosificación , Riboflavina , Bovinos , Vitamina B 12/sangre
19.
Pediatr Allergy Immunol ; 35(10): e14251, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39365274

RESUMEN

BACKGROUND: Consumption of raw cow's milk has repeatedly been shown to protect from asthma, allergies, and respiratory infections. As raw milk bears potential health hazards, it cannot be recommended for prevention. Therefore, we performed an intervention study with microbially safe but otherwise minimally processed cow's milk. Here we describe feasibility and safety of the trial. METHODS: The MARTHA trial (DRKS00014781) was set up as a double-blind randomized intervention in a population residing in Bavaria. Infants from 6 to 36 months of age consumed minimally processed cow's milk (intervention arm) or ultra-heat-treated (UHT) semi-skimmed milk (comparator arm). RESULTS: At the age of 6 to 12 months, 260 infants were enrolled, with 72% having a family history of atopy. The extensive screening system for milk consumption and symptoms suggestive of adverse events was well accepted with 22,988 completed weekly surveys and an average completion of 82% surveys sent out. The children consumed the study milk on average on 457 days (61% of intervention days). The intervention proved to be safe without any case of milk allergy or milk intolerance under the intervention in both arms. All 6 cases of serious adverse events were unrelated to milk. The most common reason was unscheduled hospitalization of more than 3 days. CONCLUSIONS: The intervention with minimally processed milk and the study instruments proved feasible. During the age of 6 to 36 months, there was no increased risk of milk allergy in a population with a substantial proportion of family history of atopy.


Asunto(s)
Estudios de Factibilidad , Hipersensibilidad a la Leche , Leche , Humanos , Lactante , Animales , Método Doble Ciego , Femenino , Masculino , Leche/efectos adversos , Leche/inmunología , Hipersensibilidad a la Leche/prevención & control , Preescolar , Alemania/epidemiología , Bovinos
20.
Pediatr Allergy Immunol ; 35(10): e14258, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39396116

RESUMEN

BACKGROUND: Infants aged <1 year with confirmed food allergies generally need to avoid causative foods completely for a certain period. Low-dose oral food challenges (LD-OFCs) may be an effective strategy for safely introducing small amounts of causative foods to individuals with food allergies. This study clarified the safety of LD-OFCs in infants aged <1 year with food allergies. METHODS: We retrospectively analyzed the clinical records of LD-OFCs performed in infants aged <1 year allergic to hen's egg, cow's milk, or wheat between April 2014 and October 2017. Approximately 1/25th-1/20th of the egg white from a heated whole hen's egg, 3 mL heated cow's milk, and 2 g wheat noodles (udon) were used as challenge foods. We examined the LD-OFC results, including the induced symptoms and treatment required for positive LD-OFC results. RESULTS: The LD-Egg, LD-Milk, and LD-Wheat OFC groups comprised 68, 42, and 13 participants, respectively. The positivity rates for the LD-Egg, LD-Milk, and LD-Wheat OFC groups were 7%, 24%, and 0%, respectively. Patients predominantly exhibited skin symptoms, and most were treated with oral antihistamines alone. None of the patients experienced anaphylaxis or required adrenaline injections. CONCLUSIONS: Infants aged <1 year with food allergies can safely undergo LD-OFCs by consuming low doses of causative foods. Avoiding the complete elimination of causative foods is an important strategy for managing infants with food allergies when initially introducing causative foods.


Asunto(s)
Alérgenos , Hipersensibilidad al Huevo , Humanos , Lactante , Estudios Retrospectivos , Femenino , Masculino , Administración Oral , Alérgenos/inmunología , Alérgenos/administración & dosificación , Hipersensibilidad a los Alimentos , Animales , Hipersensibilidad a la Leche/dietoterapia , Leche/inmunología , Hipersensibilidad al Trigo/diagnóstico , Inmunización/métodos
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