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Tolerability of a new amino acid-based formula for children with IgE-mediated cow's milk allergy. Ital J Pediatr 2021; 47:151. [PMID: 34217356 PMCID: PMC8254988 DOI: 10.1186/s13052-021-01096-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 05/31/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Amino acid-based formula (AAF) is a relevant dietary strategy for paediatric patients affected by cow's milk allergy (CMA). The present study was designed to evaluate the hypoallergenicity of a new AAF in children with immunoglobulin (Ig)E-mediated CMA. METHODS According to the criteria provided by the American Academy of Pediatrics Subcommittee on Nutrition and Allergic Diseases, we designed a prospective trial in CMA children (aged 1-36 months) aimed to demonstrate the hypoallergenicity of the new AAF in 90% of subjects with 95% confidence during the double-blind, placebo-controlled challenge (DBPCFC). A skin prick test (SPT) with the new AAF was also performed. RESULTS Twenty-nine children [all Caucasian, 55.2% male, mean age (±SD) 16.9 ± 5.7 months] were enrolled. The SPT and the DBPCFC with the new AAF were negative in all study subjects. CONCLUSIONS The study results support the hypoallergenicity of the new AAF. This formula could be considered an additional dietary option for non-breastfed children affected by CMA. TRIAL REGISTRATION The trial was registered in the ClinicalTrials.gov Protocol Registration System (ID number: NCT03909113 ).
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The Impact of Formula Choice for the Management of Pediatric Cow's Milk Allergy on the Occurrence of Other Allergic Manifestations: The Atopic March Cohort Study. J Pediatr 2021; 232:183-191.e3. [PMID: 33524387 DOI: 10.1016/j.jpeds.2021.01.059] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 01/16/2021] [Accepted: 01/23/2021] [Indexed: 02/06/2023]
Abstract
OBJECTIVES To compare the impact of different formulas on the occurrence of other atopic manifestations and the time of immune tolerance acquisition. STUDY DESIGN In a 36-month prospective cohort study, the occurrence of other atopic manifestations (eczema, urticaria, asthma, and rhinoconjunctivitis) and the time of immune tolerance acquisition were comparatively evaluated in immunoglobulin E-mediated children with cow's milk allergy (CMA) treated with extensively hydrolyzed casein formula containing the probiotic L. rhamnosus GG (EHCF + LGG), rice hydrolyzed formula, soy formula, extensively hydrolyzed whey formula (EHWF), or amino acid-based formula. RESULTS In total, 365 subjects were enrolled into the study, 73 per formula cohort. The incidence of atopic manifestations was 0.22 (Bonferroni-corrected 95% CI 0.09-0.34) in the EHCF + LGG cohort; 0.52 (0.37-0.67) in the rice hydrolyzed formula cohort; 0.58 (0.43-0.72) in the soy formula cohort; 0.51 (0.36-0.66) in the EHWF cohort; and 0.77 (0.64-0.89) in the amino acid-based formula cohort. The incidence of atopic manifestations in the rice hydrolyzed formula, soy formula, EHWF, and amino acid-based formula cohorts vs the EHCF + LGG cohort was always greater than the prespecified absolute difference of 0.25 at an alpha-level of 0.0125, with corresponding risk ratios of 2.37 (1.46-3.86, P < .001) for rice hydrolyzed formula vs EHCF + LGG; 2.62 (1.63-4.22, P < .001) for soy formula vs EHCF + LGG; 2.31 (1.42-3.77, P < .001) for EHWF vs EHCF + LGG; and 3.50 (2.23-5.49, P < .001) for amino acid-based formula vs EHCF + LGG. The 36-month immune tolerance acquisition rate was greater in the EHCF + LGG cohort. CONCLUSIONS The use of EHCF + LGG for CMA treatment is associated with lower incidence of atopic manifestations and greater rate of immune tolerance acquisition.
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MESH Headings
- Amino Acids
- Asthma/epidemiology
- Asthma/immunology
- Asthma/prevention & control
- Caseins
- Child, Preschool
- Conjunctivitis, Allergic/epidemiology
- Conjunctivitis, Allergic/immunology
- Conjunctivitis, Allergic/prevention & control
- Dermatitis, Atopic/epidemiology
- Dermatitis, Atopic/immunology
- Dermatitis, Atopic/prevention & control
- Female
- Follow-Up Studies
- Humans
- Immune Tolerance
- Incidence
- Infant
- Infant Formula/adverse effects
- Infant Formula/chemistry
- Infant Formula/microbiology
- Lacticaseibacillus rhamnosus
- Male
- Milk Hypersensitivity/complications
- Milk Hypersensitivity/diet therapy
- Milk Hypersensitivity/immunology
- Oryza
- Probiotics/therapeutic use
- Prospective Studies
- Rhinitis, Allergic/epidemiology
- Rhinitis, Allergic/immunology
- Rhinitis, Allergic/prevention & control
- Glycine max
- Treatment Outcome
- Whey
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Tolerogenic Effect Elicited by Protein Fraction Derived From Different Formulas for Dietary Treatment of Cow's Milk Allergy in Human Cells. Front Immunol 2021; 11:604075. [PMID: 33679694 PMCID: PMC7928417 DOI: 10.3389/fimmu.2020.604075] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 12/29/2020] [Indexed: 01/07/2023] Open
Abstract
Several formulas are available for the dietary treatment of cow’s milk allergy (CMA). Clinical data suggest potentially different effect on immune tolerance elicited by these formulas. We aimed to comparatively evaluate the tolerogenic effect elicited by the protein fraction of different formulas available for the dietary treatment of CMA. Five formulas were compared: extensively hydrolyzed whey formula (EHWF), extensively hydrolyzed casein formula (EHCF), hydrolyzed rice formula (HRF), soy formula (SF), and amino acid-based formula (AAF). The formulas were reconstituted in water according to the manufacturer’s instructions and subjected to an in vitro infant gut simulated digestion using a sequential gastric and duodenal static model. Protein fraction was then purified and used for the experiments on non-immune and immune components of tolerance network in human enterocytes and in peripheral mononuclear blood cells (PBMCs). We assessed epithelial layer permeability and tight junction proteins (occludin and zonula occludens-1, ZO-1), mucin 5AC, IL-33, and thymic stromal lymphopoietin (TSLP) in human enterocytes. In addition, Th1/Th2 cytokine response and Tregs activation were investigated in PBMCs from IgE-mediated CMA infants. EHCF-derived protein fraction positively modulated the expression of gut barrier components (mucin 5AC, occludin and ZO-1) in human enterocytes, while SF was able to stimulate the expression of occludin only. EHWF and HRF protein fractions elicited a significant increase in TSLP production, while IL-33 release was significantly increased by HRF and SF protein fractions in human enterocytes. Only EHCF-derived protein fraction elicited an increase of the tolerogenic cytokines production (IL-10, IFN-γ) and of activated CD4+FoxP3+ Treg number, through NFAT, AP1, and Nf-Kb1 pathway. The effect paralleled with an up-regulation of FoxP3 demethylation rate. Protein fraction from all the study formulas was unable to induce Th2 cytokines production. The results suggest a different regulatory action on tolerogenic mechanisms elicited by protein fraction from different formulas commonly used for CMA management. EHCF-derived protein fraction was able to elicit tolerogenic effect through at least in part an epigenetic modulation of FoxP3 gene. These results could explain the different clinical effects observed on immune tolerance acquisition in CMA patients and on allergy prevention in children at risk for atopy observed using EHCF.
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Reply to "Efficacy and safety of hydrolyzed formulas for cow's milk allergy management: A systematic review of randomized controlled trials". Clin Exp Allergy 2020; 51:155-157. [PMID: 33047369 DOI: 10.1111/cea.13758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 10/01/2020] [Indexed: 11/30/2022]
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Editorial: interventions in infantile colic - can efficacy be attributed to treatment or to time? Authors' reply. Aliment Pharmacol Ther 2020; 51:398-399. [PMID: 31943267 DOI: 10.1111/apt.15627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
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The therapeutic efficacy of Bifidobacterium animalis subsp. lactis BB-12 ® in infant colic: A randomised, double blind, placebo-controlled trial. Aliment Pharmacol Ther 2020; 51:110-120. [PMID: 31797399 PMCID: PMC6973258 DOI: 10.1111/apt.15561] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 06/24/2019] [Accepted: 10/06/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND The pathogenesis of infant colic is poorly defined. Gut microbiota seems to be involved, supporting the potential therapeutic role of probiotics. AIMS To assess the rate of infants with a reduction of ≥50% of mean daily crying duration after 28 days of intervention with the probiotic Bifidobacterium animalis subsp. lactis BB-12® (BB-12). Secondary outcomes were daily number of crying episodes, sleeping time, number of bowel movements and stool consistency. METHODS Randomized controlled trial (RCT) on otherwise healthy exclusively breastfed infants with infant colic randomly allocated to receive BB-12 (1 × 109 CFU/day) or placebo for 28 days. Gut microbiota structure and butyrate, beta-defensin-2 (HBD-2), cathelicidin (LL-37), secretory IgA (sIgA) and faecal calprotectin levels were assessed. RESULTS Eighty infants were randomised, 40/group. The rate of infants with reduction of ≥50% of mean daily crying duration was higher in infants treated with BB-12, starting from the end of 2nd week. No infant relapsed when treatment was stopped. The mean number of crying episodes decreased in both groups, but with a higher effect in BB-12 group (-4.7 ± 3.4 vs -2.3 ± 2.2, P < 0.05). Mean daily stool frequency decreased in both groups but the effect was significantly higher in the BB-12 group; stool consistency was similar between the two groups. An increase in Bifidobacterium abundance (with significant correlation with crying time reduction), butyrate and HBD-2, LL-37, sIgA levels associated with a decrease in faecal calprotectin level were observed in the BB-12 group. CONCLUSIONS Supplementation with BB-12 is effective in managing infant colic. The effect could derive from immune and non-immune mechanisms associated with a modulation of gut microbiota structure and function.
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Dietary Treatment with Extensively Hydrolyzed Casein Formula Containing the Probiotic Lactobacillus rhamnosus GG Prevents the Occurrence of Functional Gastrointestinal Disorders in Children with Cow's Milk Allergy. J Pediatr 2019; 213:137-142.e2. [PMID: 31327562 DOI: 10.1016/j.jpeds.2019.06.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 05/09/2019] [Accepted: 06/04/2019] [Indexed: 12/19/2022]
Abstract
OBJECTIVE To investigate whether the addition of the probiotic Lactobacillus rhamnosus GG (LGG) to the extensively hydrolyzed casein formula (EHCF) for cow's milk allergy (CMA) treatment could reduce the occurrence of functional gastrointestinal disorders (FGIDs). STUDY DESIGN This cohort study included children with a positive history for CMA in the first year of life who were treated with EHCF alone or in combination with LGG and had evidence of immune tolerance acquisition to cow's milk for at least 12 months. FGID was diagnosed according to the Rome III diagnostic criteria by investigators unaware of previous treatment. A cohort of consecutive healthy children was also evaluated as a control population. RESULTS A total of 330 subjects were included, 110 per cohort (EHCF, EHCF+LGG, and healthy controls). The rate of subjects with ≥1 FGID was significantly lower in the EHCF+LGG cohort compared with the EHCF cohort (40% vs 16.4%; P < .05). In the EHCF+LGG cohort, a lower incidence was observed for all components of the main study outcome. The prevalence of FGIDs in the healthy cohort was lower than that in the EHCF cohort and similar to that in the EHCF+LGG cohort. The incidence rate ratio of FGIDs for the EHCF+LGG cohort vs the EHCF cohort (0.40; 95% CI, 0.25-0.65; P < .001) was unmodified after correction for age at CMA diagnosis, breastfeeding, weaning time, and presence of a first-degree relative with an FGID. CONCLUSIONS These results confirm the increased risk for developing FGIDs in children with CMA and suggest that EHCF+LGG could reduce this risk.
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Publisher Correction: Randomized controlled trial on the influence of dietary intervention on epigenetic mechanisms in children with cow's milk allergy: the EPICMA study. Sci Rep 2019; 9:9504. [PMID: 31239464 PMCID: PMC6593099 DOI: 10.1038/s41598-019-45226-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
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Randomized controlled trial on the influence of dietary intervention on epigenetic mechanisms in children with cow's milk allergy: the EPICMA study. Sci Rep 2019; 9:2828. [PMID: 30808949 PMCID: PMC6391485 DOI: 10.1038/s41598-019-38738-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 01/09/2019] [Indexed: 12/17/2022] Open
Abstract
Epigenetic mechanisms could drive the disease course of cow’s milk allergy (CMA) and formula choice could modulate these pathways. We compared the effect of two different dietary approaches on epigenetic mechanisms in CMA children. Randomized controlled trial on IgE-mediated CMA children receiving a 12-month treatment with extensively hydrolyzed casein formula containing the probiotic L.rhamnosus GG (EHCF + LGG) or with soy formula (SF). At the baseline, after 6 and 12 months of treatment FoxP3 methylation rate and its expression in CD4+ T cells were assessed. At same study points IL-4, IL-5, IL-10, and IFN-γ methylation rate, expression and serum concentration, miRNAs expression were also investigated. 20 children (10/group) were evaluated. Baseline demographic, clinical and epigenetic features were similar in the two study groups. At 6 and 12 months, EHCF + LGG group showed a significant increase in FoxP3 demethylation rate compared to SF group. At the same study points, EHCF + LGG group presented a higher increase in IL-4 and IL-5 and a higher reduction in IL-10 and IFN-γ DNA methylation rate compared to SF group. A different modulation of miR-155, -146a, -128 and -193a expression was observed in EHCF + LGG vs. SF. Dietary intervention could exert a different epigenetic modulation on the immune system in CMA children.
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Safety and effectiveness of percutaneous electrical nerve stimulation on pain reduction in patients suffering from neuropathic or mixed pain. Ann Phys Rehabil Med 2018. [DOI: 10.1016/j.rehab.2018.05.231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Development of a patient-centered questionnaire for post-stroke spasticity assessment: a reliability study. FUNCTIONAL NEUROLOGY 2018; 33:113-115. [PMID: 29984689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In the emerging scenario of patient-centered medicine, it is becoming increasingly important to involve patients in the management of chronic diseases. The rehabilitation field currently has no assessment tool for evaluating the functional impact of post-stroke spasticity on activities of daily living. The aim of this study was to identify a tool to fill this gap. The "Spasticity Questionnaire in Real Life" (SPQR) was administered, twice, to 39 patients with poststroke spasticity. Statistical analysis showed internal consistency and reliability of the questionnaire, with values greater than 0.96 and 0.76, respectively. These results show that the SPQR is a promising tool for evaluating the functional impact of post-stroke spasticity.
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Gut Microbiota as a Target for Preventive and Therapeutic Intervention against Food Allergy. Nutrients 2017; 9:nu9070672. [PMID: 28657607 PMCID: PMC5537787 DOI: 10.3390/nu9070672] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 06/15/2017] [Accepted: 06/23/2017] [Indexed: 12/24/2022] Open
Abstract
The gut microbiota plays a pivotal role in immune system development and function. Modification in the gut microbiota composition (dysbiosis) early in life is a critical factor affecting the development of food allergy. Many environmental factors including caesarean delivery, lack of breast milk, drugs, antiseptic agents, and a low-fiber/high-fat diet can induce gut microbiota dysbiosis, and have been associated with the occurrence of food allergy. New technologies and experimental tools have provided information regarding the importance of select bacteria on immune tolerance mechanisms. Short-chain fatty acids are crucial metabolic products of gut microbiota responsible for many protective effects against food allergy. These compounds are involved in epigenetic regulation of the immune system. These evidences provide a foundation for developing innovative strategies to prevent and treat food allergy. Here, we present an overview on the potential role of gut microbiota as the target of intervention against food allergy.
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Extensively hydrolyzed casein formula containing Lactobacillus rhamnosus GG reduces the occurrence of other allergic manifestations in children with cow's milk allergy: 3-year randomized controlled trial. J Allergy Clin Immunol 2016; 139:1906-1913.e4. [PMID: 28043872 DOI: 10.1016/j.jaci.2016.10.050] [Citation(s) in RCA: 132] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 09/13/2016] [Accepted: 10/17/2016] [Indexed: 01/19/2023]
Abstract
BACKGROUND Children with cow's milk allergy (CMA) have an increased risk of other allergic manifestations (AMs). OBJECTIVE We performed a parallel-arm randomized controlled trial to test whether administration of an extensively hydrolyzed casein formula (EHCF) containing the probiotic Lactobacillus rhamnosus GG (LGG) can reduce the occurrence of other AMs in children with CMA. METHODS Children with IgE-mediated CMA were randomly allocated to the EHCF or EHCF+LGG groups and followed for 36 months. The main outcome was occurrence of at least 1 AM (eczema, urticaria, asthma, and rhinoconjunctivitis). The secondary outcome was tolerance acquisition, which was defined as the negativization of a double-blind food challenge results at 12, 24, and 36 months. AMs were diagnosed according to standardized criteria. Tolerance acquisition was evaluated every 12 months. RESULTS A total of 220 children (147 boys [67%]) with a median age of 5.0 months (interquartile range, 3.0-8.0 months) were randomized; 110 children were placed in the EHCF group, and 110 children were placed in the EHCF+LGG group. In the complete case analysis the absolute risk difference for the occurrence of at least 1 AM over 36 months was -0.23 (95% CI, -0.36 to -0.10; P < .001), and the absolute risk difference for the acquisition of cow's milk tolerance was 0.20 (95% CI, 0.05-0.35; P < .01) at 12 months, 0.24 (95% CI, 0.08-0.41; P < .01) at 24 months, and 0.27 (95% CI, 0.11-0.43; P < .001) at 36 months. In the sensitivity analysis the effect size of the main outcome was virtually unchanged when the occurrence of AMs was assigned to all 27 missing children. CONCLUSIONS EHCF+LGG reduces the incidence of other AMs and hastens the development of oral tolerance in children with IgE-mediated CMA.
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Epigenetic features of FoxP3 in children with cow's milk allergy. Clin Epigenetics 2016; 8:86. [PMID: 27525046 PMCID: PMC4981981 DOI: 10.1186/s13148-016-0252-z] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 08/02/2016] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND DNA methylation of the Th1 and Th2 cytokine genes is altered during cow's milk allergy (CMA). Forkhead box transcription factor 3 (FoxP3) is essential for the development and function of regulatory T cells (Tregs) and is involved in oral tolerance acquisition. We assessed whether tolerance acquisition in children with IgE-mediated CMA is associated with DNA demethylation of the Treg-specific demethylated region (TSDR) of FoxP3. RESULTS Forty children (aged 3-18 months) were enrolled: 10 children with active IgE-mediated CMA (group 1), 10 children who outgrew CMA after dietary treatment with an extensively hydrolyzed casein formula containing the probiotic Lactobacillus rhamnosus GG (group 2), 10 children who outgrew CMA after treatment with other formulas (group 3), and 10 healthy controls (group 4). FoxP3 TSDR demethylation and expression were measured in mononuclear cells purified from peripheral blood of the four groups of children. FoxP3 TSDR demethylation was significantly lower in children with active IgE-mediated CMA than in either children who outgrew CMA or in healthy children. Formula selection influenced the FoxP3 TSDR demethylation profile. The FoxP3 TSDR demethylation rate and expression level were correlated. CONCLUSIONS Tolerance acquisition in children with IgE-mediated CMA involves epigenetic regulation of the FoxP3 gene. This feature could be a new target for preventive and therapeutic strategies against CMA.
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Bugs for atopy: the Lactobacillus rhamnosus GG strategy for food allergy prevention and treatment in children. Benef Microbes 2016; 6:225-32. [PMID: 25851101 DOI: 10.3920/bm2014.0158] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Food allergy (FA) is a major health issue for children living in Western countries. At this time the only proven treatment for FA is elimination of offender antigen from the diet. It is becoming clear that the development of gut microbiota exerts a profound influence on immune system maturation and tolerance acquisition. Increasing evidence suggests that perturbations in gut microbiota composition of infants are implicated in the pathogenesis of FA. These findings have unveiled new strategies to prevent and treat FA using probiotics bacteria or bacterial substance to limit T-helper (Th)/Th2 bias, which changes during the disease course. Selected probiotics administered during infancy may have a role in the prevention and treatment of FA. Lactobacillus rhamnosus GG (LGG) is the most studied probiotic in this field. Administration of LGG in early life have a role in FA prevention. Preliminary evidence shows that LGG accelerates oral tolerance acquisition in cow's milk allergic infants. We are understanding the mechanisms elicited by LGG and metabolites in influencing food allergen sensitization. A deeper definition of these mechanisms is opening the way to new immunotherapeutics for children affected by FA that can efficiently limit the disease burden.
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Cow's milk and rice fermented with Lactobacillus paracasei CBA L74 prevent infectious diseases in children: A randomized controlled trial. Clin Nutr 2015; 36:118-125. [PMID: 26732025 DOI: 10.1016/j.clnu.2015.12.004] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 11/24/2015] [Accepted: 12/10/2015] [Indexed: 11/25/2022]
Abstract
BACKGROUND & AIM Fermented foods have been proposed for the prevention of infectious diseases. We evaluated the efficacy of fermented foods in reducing common infectious diseases (CIDs) in children attending daycare. METHODS Prospective randomized, double-blind, placebo-controlled trial (registered under Clinical Trials.gov identifier NCT01909128) on healthy children (aged 12-48 months) consuming daily cow's milk (group A) or rice (group B) fermented with Lactobacillus paracasei CBA L74, or placebo (group C) for three months during the winter season. The main study outcome was the proportion of children who experienced at least one CID. All CIDs were diagnosed by family pediatricians. Fecal concentrations of innate (α- and β-defensins and cathelicidin LL-37) and acquired immunity biomarkers (secretory IgA) were also evaluated. RESULTS 377 children (193 males, 51%) with a mean (SD) age of 32 (10) months completed the study: 137 in group A, 118 in group B and 122 in group C. Intention-to-treat analysis showed that the proportion of children who experienced at least one CID was lower in group A (51.8%) and B (65.9%) compared to group C (80.3%). Per-protocol analysis showed that the proportion of children presenting upper respiratory tract infections was lower in group A (48.2%) and group B (58.5%) compared with group C (70.5%). The proportion of children presenting acute gastroenteritis was also lower in group A (13.1%) and group B (19.5%) compared with group C (31.1%). A net increase of all fecal biomarkers of innate and acquired immunity was observed for groups A and B compared to group C. Moreover, there was a negative association between fecal biomarkers and the occurrence of CID. CONCLUSION Dietary supplementation with cow's milk or rice fermented with L. paracasei CBA L74 prevents CIDs in children attending daycare possibly by means of a stimulation of innate and acquired immunity.
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Differences in DNA methylation profile of Th1 and Th2 cytokine genes are associated with tolerance acquisition in children with IgE-mediated cow's milk allergy. Clin Epigenetics 2015; 7:38. [PMID: 25859290 PMCID: PMC4391731 DOI: 10.1186/s13148-015-0070-8] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 03/10/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Epigenetic changes in DNA methylation could regulate the expression of several allergy-related genes. We investigated whether tolerance acquisition in children with immunoglobulin E (IgE)-mediated cow's milk allergy (CMA) is characterized by a specific DNA methylation profile of Th2 (IL-4, IL-5) and Th1 (IL-10, IFN-γ)-associated cytokine genes. RESULTS DNA methylation of CpGs in the promoting regions of genes from peripheral blood mononuclear cells and serum level of IL-4, IL-5, IL-10 and INF-γ were assessed in children with active IgE-mediated CMA (group 1), in children who acquired tolerance to cow's milk proteins (group 2) and in healthy children (group 3). Forty children (24 boys, aged 3 to 18 months) were enrolled: 10 in group 1, 20 in group 2, and 10 in the control group. The DNA methylation profiles clearly separated active CMA patients from healthy controls. We observed an opposite pattern comparing subjects with active IgE-mediated CMA with healthy controls and group 2 children who outgrew CMA. The IL-4 and IL-5 DNA methylation was significantly lower, and IL-10 and INF-γ DNA methylation was higher in active IgE-mediated CMA patients. Gene promoter DNA methylation rates of all cytokines and respective serum levels were strongly correlated. Formula selection significantly influenced cytokine DNA methylation profiles in group 2. CONCLUSIONS Tolerance acquisition in children with IgE-mediated CMA is characterized by a distinct Th1 and Th2 cytokine gene DNA methylation pattern. These results suggest that DNA methylation may be a target for CMA prevention and treatment.
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Increasing rate of hospitalizations for food-induced anaphylaxis in Italian children: An analysis of the Italian Ministry of Health database. J Allergy Clin Immunol 2015; 135:833-5.e3. [DOI: 10.1016/j.jaci.2014.12.1912] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 12/15/2014] [Accepted: 12/16/2014] [Indexed: 12/28/2022]
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The Effects of Dietary Counseling on Children with Food Allergy: A Prospective, Multicenter Intervention Study. J Acad Nutr Diet 2014; 114:1432-9. [DOI: 10.1016/j.jand.2014.03.018] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 03/28/2014] [Indexed: 10/25/2022]
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Abstract
Diarrhoea in infants and young children is defined as >200g/day of stools, and occurs when there is an imbalance between intestinal fluids absorption and secretion. This may be caused by either a decreased absorption (osmotic diarrhoea) or an increased secretion (secretory diarrhoea). Chronic diarrhoea defines intestinal loss of water and electrolytes with increased stool frequency, reduced consistency and larger volume over more than 14days. This disorder in children shows a wide range of aetiologies depending on the age. The knowledge of common and rare aetiologies is important to optimize the diagnostic approach. A stepwise approach, starting with a comprehensive history, physical examination, inspection and collection of stool samples, helps to devise appropriate diagnostic and therapeutic management. In this article we discuss the pathophysiology, aetiology and possible approach to chronic diarrhoea in infancy.
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Formula selection for management of children with cow's milk allergy influences the rate of acquisition of tolerance: a prospective multicenter study. J Pediatr 2013; 163:771-7.e1. [PMID: 23582142 DOI: 10.1016/j.jpeds.2013.03.008] [Citation(s) in RCA: 142] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Revised: 01/25/2013] [Accepted: 03/06/2013] [Indexed: 12/26/2022]
Abstract
OBJECTIVES To prospectively evaluate the effect of different dietary management strategies on the rate of acquisition of tolerance in children with cow's milk allergy (CMA). STUDY DESIGN Otherwise healthy children (aged 1-12 months) diagnosed with CMA were prospectively evaluated. The study population was divided into 5 groups based upon the formula used for management: (1) extensively hydrolyzed casein formula ([EHCF], n = 55); (2) EHCF + Lactobacillus rhamnosus GG [LGG], n = 71); (3) hydrolyzed rice formula (RHF, n = 46); (4) soy formula (n = 55); and (5) amino acid based formula (n = 33). A food challenge was performed after 12 months to assess acquisition of tolerance. RESULTS Two hundred sixty children were evaluated (167 male, 64.2%; age 5.92 months, 95% CI 5.48-6.37; body weight 6.66 kg, 95% CI 6.41-6.91; IgE-mediated CMA 111, 42.7%). The rate of children acquiring oral tolerance after 12 months was significantly higher (P < .05) in the groups receiving EHCF (43.6%) or EHCF + LGG (78.9%) compared with the other groups: RHF (32.6%), soy formula (23.6%), and amino acid based formula (18.2%). Binary regression analysis coefficient (B) revealed that the rate of patients acquiring tolerance at the end of the study was influenced by 2 factors: (1) IgE-mediated mechanism (B -2.05, OR 0.12, 95% CI 0.06-0.26; P < .001); and (2) formula choice, such that those receiving either EHCF (B 1.48, OR 4.41, 95% CI 1.44-13.48; P = .009) or EHCF + LGG (B 3.35, OR 28.62, 95% CI 8.72-93.93; P < .001). CONCLUSIONS EHCF accelerates tolerance acquisition in children with CMA if compared with other dietetic choices. This effect is augmented by LGG.
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Calcium and vitamin D intakes in children: a randomized controlled trial. BMC Pediatr 2013; 13:86. [PMID: 23702146 PMCID: PMC3665520 DOI: 10.1186/1471-2431-13-86] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 05/15/2013] [Indexed: 11/23/2022] Open
Abstract
Background Calcium (Ca2+) and vitamin D (VitD) play an important role in child health. We evaluated the daily intake of Ca2+ and VitD in healthy children. Moreover, we demonstrate the efficacy of Ca2+ and VitD supplementation. Methods Daily Ca2 + and VitD intake was evaluated in consecutive healthy children through a validated questionnaire. Subjects with <70% of dietary reference intakes (DRIs) of Ca2+ and VitD were invited to participate in a prospective randomized trial with 2 groups of nutritional intervention: Group 1, dietary counseling aiming to optimize daily Ca2+ and VitD intake plus administration of a commercially available Ca2 + and VitD supplementation product; Group 2, dietary counseling alone. At the enrollment (T0) and after 4 months (T1) serum 25(OH) Vitamin D levels were assessed. Results We evaluated 150 healthy children (male 50%, mean age 10 years); at baseline a low VitD intake was observed in all subjects (median 0.79 μg/die, IQR 1.78; range 0.01-5.02); this condition was associated with Ca2+ intake <70% of the DRIs in 82 subjects (55%). At baseline serum 25(OH)D levels were low (<30 ng/ml) in all study subjects and after 4 months of nutritional intervention, a normalization of serum 25(OH)D levels (≥30 ng/ml) was observed in all children in Group 1 and in only one subject in Group 2 [Group 1: T1 33.8 ng/ml (IQR 2.5) vs Group 2: T1 24.5 ng/ml (IQR 5.2), p <0.001]. Conclusions Adequate Ca2+ and VitD intakes are difficult to obtain through dietary counseling alone in pediatric subjects. Oral supplementation with of Ca2+ and VitD is a reliable strategy to prevent this condition. Trial registration The study was registered in Clinical Trials Protocol Registration System (ID number: NCT01638494).
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Tolerance to a new free amino acid-based formula in children with IgE or non-IgE-mediated cow's milk allergy: a randomized controlled clinical trial. BMC Pediatr 2013; 13:24. [PMID: 23418822 PMCID: PMC3583738 DOI: 10.1186/1471-2431-13-24] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 01/31/2013] [Indexed: 11/16/2022] Open
Abstract
Background Amino acid-based formulas (Aaf) are increasingly used in children with cow’s milk allergy (CMA). To be labeled hypoallergenic these formulas must demonstrate in clinical studies that they don’t provoke reactions in 90% of subjects with confirmed CMA with 95% confidence when given in prospective randomized, double-blind, placebo-controlled challenge (DBPCFC) trials. The majority of available safety data on Aaf derived from patients with IgE-mediated CMA. Considering substantial differences in the immunologic mechanism and clinical presentation of non-IgE-mediated CMA it’s important to investigate the hypoallergenicity of these formulas also in these patients. We prospectively assessed the tolerance to a new commercially available Aaf in children affected by IgE- or non-IgE-mediated CMA. Methods Consecutive patients affected by IgE- or non-IgE-mediated CMA, aged ≤ 4 years, were enrolled. DBPCFC was carried out with increasing doses of the new Aaf (Sineall, Humana, Milan, Italy), using validated Aaf as placebo. Faecal concentrations of calprotectin (FC) and eosinophilic cationic protein (ECP) were monitored. Results Sixty patients (44 male, 73.3%, median age 37, 95%CI 34.5–39.6 months, IgE-mediated CMA 29, 48.3%) were enrolled. At the diagnosis clinical symptoms were gastrointestinal (46.6%), cutaneous (36.6%), respiratory (23.3%), and systemic (10.0%). After DBPCFC with the new Aaf, no patient presented early or delayed clinical reactions. Faecal concentration of calprotectin and of ECP remained stable after the exposure to the new Aaf. Conclusions The new Aaf is well tolerated in children with IgE- or non-IgE-mediated CMA, and it could be used as a safe dietotherapy regimen for children with this condition. Trial registration The trial was registered in the ClinicalTrials.gov Protocol Registration System (ID number: NCT01622426).
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Role of Probiotics in Allergies. World Rev Nutr Diet 2013. [DOI: 10.1159/000345741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Randomised clinical trial: efficacy of a new synbiotic formulation containing Lactobacillus paracasei B21060 plus arabinogalactan and xilooligosaccharides in children with acute diarrhoea. Aliment Pharmacol Ther 2012; 35:782-8. [PMID: 22324448 DOI: 10.1111/j.1365-2036.2012.05015.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 09/21/2011] [Accepted: 01/19/2012] [Indexed: 12/19/2022]
Abstract
BACKGROUND Acute diarrhoea is a frequent problem in children with heavy economic burden for families and society. AIM To test the efficacy of a new synbiotic formulation containing Lactobacillus paracasei B21060, arabinogalactan and xilooligosaccharides in children with acute diarrhoea. METHODS Double-blind, randomised, placebo-controlled trial, including children (age 3-36 m) with acute diarrhoea who were allocated to placebo or synbiotic group. Major outcome was resolution rate of diarrhoea at 72 h. Total duration of diarrhoea, daily stool outputs, stool consistency, working days lost by parents, adjunctive medications, and hospitalisation were also assessed. RESULTS We enrolled 55 children in placebo group and 52 in synbiotic group. The two groups were similar for demographic and clinical characteristics. Resolution rate of diarrhoea at 72 h was significantly higher in synbiotic group (67%) compared to placebo group (40%, P = 0.005). Children in synbiotic group showed a significant reduction in the duration of diarrhoea (90.5 h, 78.1-102.9 vs. 109.8 h, 96.0-123.5, P = 0.040), daily stool outputs (3.3, 2.8-3.8 vs. 2.4, 1.9-2.8, P = 0.005) and stool consistency (1.3, 0.9-1.6 vs. 0.6, 0.4-0.9, P = 0.002) compared to placebo group (data expressed as mean, 95% CI). Rate of parents that missed at least one working day (41.8% vs. 15.4%, P = 0.003), rate of children that needed adjunctive medications (25.5% vs. 5.8%, P = 0.005) or hospitalisation (10.9% vs. 0%, P = 0.014) after the first 72 h of treatment, were reduced in synbiotic group. CONCLUSION The synbiotic formulation studied is effective in children with acute diarrhoea. Australian New Zealand Clinical Trials Registry (ACTRN12611000641998).
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Toward a standardized reading of the atopy patch test in children with suspected cow's milk allergy-related gastrointestinal symptoms. Allergy 2011; 66:1499-500. [PMID: 21752029 DOI: 10.1111/j.1398-9995.2011.02674.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Efficacy of a new hypotonic oral rehydration solution containing zinc and prebiotics in the treatment of childhood acute diarrhea: a randomized controlled trial. J Pediatr 2011; 158:288-92.e1. [PMID: 20828714 DOI: 10.1016/j.jpeds.2010.07.055] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2010] [Revised: 06/23/2010] [Accepted: 07/27/2010] [Indexed: 12/25/2022]
Abstract
OBJECTIVE To evaluate the efficacy of a hypotonic oral rehydration solution (ORS) containing zinc and prebiotics for treatment of acute diarrhea in children. STUDY DESIGN We conducted a single-blind, prospective, controlled trial including children (age range, 3-36 months) with acute diarrhea randomly assigned to standard hypotonic ORS (group 1) or to new hypotonic ORS containing zinc and prebiotics (group 2). The main outcome was the rate of resolution of diarrhea at 72 hours. RESULTS A total of 60 children in group 1 (34 male; mean age, 18.58 months; 95% CI, 15.5-21.6) and 59 in group 2 (36 male; mean age, 19.26 months; 95% CI, 15.9-22.6) completed the study protocol. The rate of diarrhea resolution at 72 hours was higher in group 2 (50% versus 72.9%, P = .010). Total ORS intake in the first 24 hours was higher in group 2 (50 mL/kg; 95% CI, 41-59 versus 22 mL/kg; 95% CI, 17-29; P < .001). The mean number of missed working days by the parents of children in group 2 was lower (0.39; 95% CI, 0.08-0.70 versus 1.45; 95% CI 1.02-1.88; P < .001). Fewer patients in group 2 needed adjunctive drugs for the treatment of diarrhea 6/59 versus 19/60, P = .004. No adverse events were observed in either of the two groups. CONCLUSION The addition of zinc and prebiotics to ORS limits diarrhea duration in children.
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Faecal calprotectin as reliable non-invasive marker to assess the severity of mucosal inflammation in children with inflammatory bowel disease. Dig Liver Dis 2008; 40:547-53. [PMID: 18358796 DOI: 10.1016/j.dld.2008.01.017] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Revised: 12/18/2007] [Accepted: 01/30/2008] [Indexed: 12/11/2022]
Abstract
BACKGROUND An accurate monitoring of mucosal inflammation is important for an effective management of patients with inflammatory bowel disease. Intestinal inflammation can be detected by faecal calprotectin level determination. AIM To comparatively evaluate the accuracy of faecal calprotectin, clinical scores, common serum markers and endoscopy in the assessment of the severity of intestinal mucosa inflammation in children with inflammatory bowel disease. METHODS Fifty-eight paediatric patients (mean age 13.9 years, 95% CI 2.9-14.8; male 28) with confirmed inflammatory bowel disease (26 Crohn's disease, 32 ulcerative colitis) were enrolled. Before endoscopy, all patients underwent a complete evaluation including: clinical scores, erythrocyte sedimentation rate, C-reactive protein and faecal calprotectin determination. The severity of mucosal inflammation was assessed using specific endoscopic and histologic scores. RESULTS Faecal calprotectin showed a high correlation (r=0.655) with the histologic grade of mucosal inflammation, similar to that observed for endoscopy (r=0.699), and it resulted the most accurate tool (sensitivity 94%, specificity 64%, positive predictive value 81%, negative predictive value 87%) to detect the presence of active mucosal inflammation when compared to clinical scores and common serum markers. In patients with apparent clinical and laboratory remission the accuracy of faecal calprotectin resulted further improved (sensitivity 100%, specificity 80%, positive predictive value 67%, negative predictive value 100%). CONCLUSIONS A more accurate assessment of the severity of mucosal inflammation can be achieved by the determination of faecal calprotectin levels compared to other common clinical and laboratory indices. This non-invasive and objective method could be particular useful in patients with apparent clinical and laboratory remission.
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Comparative model building of interleukin-7 using interleukin-4 as a template: a structural hypothesis that displays atypical surface chemistry in helix D important for receptor activation. Protein Sci 2000; 9:916-26. [PMID: 10850801 PMCID: PMC2144647 DOI: 10.1110/ps.9.5.916] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Using a combination of theoretical sequence structure recognition predictions and experimental disulfide bond assignments, a three-dimensional (3D) model of human interleukin-7 (hIL-7) was constructed that predicts atypical surface chemistry in helix D that is important for receptor activation. A 3D model of hIL-7 was built using the X-ray crystal structure of interleukin-4 (IL-4) as a template (Walter MR et al., 1992, J Mol Biol. 224:1075-1085; Walter MR et al., 1992, J Biol Chem 267:20371-20376). Core secondary structures were constructed from sequences of hIL-7 predicted to form helices. The model was constructed by superimposing IL-7 helices onto the IL-4 template and connecting them together in an up-up down-down topology. The model was finished by incorporating the disulfide bond assignments (Cys3, Cys142), (Cys35, Cys130), and (Cys48, Cys93), which were determined by MALDI mass spectroscopy and site-directed mutagenesis (Cosenza L, Sweeney E, Murphy JR, 1997, J Biol Chem 272:32995-33000). Quality analysis of the hIL-7 model identified poor structural features in the carboxyl terminus that, when further studied using hydrophobic moment analysis, detected an atypical structural property in helix D, which contains Cys 130 and Cys142. This analysis demonstrated that helix D had a hydrophobic surface exposed to bulk solvent that accounted for the poor quality of the model, but was suggestive of a region in IL-7 that maybe important for protein interactions. Alanine (Ala) substitution scanning mutagenesis was performed to test if the predicted atypical surface chemistry of helix D in the hIL-7 model is important for receptor activation. This analysis resulted in the construction, purification, and characterization of four hIL-7 variants, hIL-7(K121A), hIL-7(L136A), hIL-7(K140A), and hIL-7(W143A), that displayed reduced or abrogated ability to stimulate a murine IL-7 dependent pre-B cell proliferation. The mutant hIL-7(W143A), which is biologically inactive and displaces [125I]-hIL-7, is the first reported IL-7R system antagonist.
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Disulfide bond assignment in human interleukin-7 by matrix-assisted laser desorption/ionization mass spectroscopy and site-directed cysteine to serine mutational analysis. J Biol Chem 1997; 272:32995-3000. [PMID: 9407080 DOI: 10.1074/jbc.272.52.32995] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Interleukin-7 (IL-7) is a proteinaceous biological response modifier that has a bioactive tertiary structure dependent on disulfide bond formation. Disulfide bond assignments in human (h)IL-7 are based upon the results of matrix-assisted laser desorption/ionization (MALDI) mass spectroscopy and Cys to Ser mutational analyses. A gene encoding the hIL-7 was synthesized incorporating Escherichia coli codon usage bias and was used to express biologically active protein as determined by stimulation of precursor B-cell proliferation. MALDI mass spectroscopic analysis of trypsin-digested hIL-7 was performed and compared with the anticipated results of a simulated tryptic digestion. Many of the anticipated hIL-7 tryptic fragments were detected including one with a molecular mass equivalent to the sum of two polypeptides linked through a disulfide bond formed from Cys residues (Cys3 and Cys142). Subsequently, Cys to Ser substitution mutational analyses were performed. A hIL-7 variant with all six Cys substituted with Ser was found to be biologically inactive (EC50 > 1 x 10(-7) M). In contrast, a family of single disulfide bond-forming variants of hIL-7 were constructed by reintroducing Cys pairs (Cys3-Cys142, Cys35-Cys130, and Cys48-Cys93), and each could stimulate cell proliferation with an EC50 of 4 x 10(-9), 2 x 10(-8), and 2 x 10(-9) M, respectively. In single disulfide bond-forming mutants of hIL-7, the ability to stimulate cell proliferation was abolished in the presence of 2 mM dithiothreitol. The results presented strongly suggest that only a single disulfide bond is required for hIL-7 to form a tertiary structure capable of stimulating precursor B-cell proliferation.
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Diphtheria toxin-related cytokine fusion proteins: elongation factor 2 as a target for the treatment of neoplastic disease. Mol Cell Biochem 1994; 138:151-6. [PMID: 7898459 DOI: 10.1007/bf00928457] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We have used protein engineering and recombinant DNA methodologies in order to construct a fusion protein in which human interleukin-2 (IL-2) is genetically linked to the catalytic and transmembrane domains of diphtheria toxin. The fusion toxin, DAB486IL-2, is highly cytotoxic for only those cells which display the high affinity interleukin-2 receptor (IL-2R) on their surface. In phase I/II clinical studies the intravenous administration of DAB486IL-2 has been found to be safe, well tolerated and may lead to the induction of durable remissions in patients presenting with a variety of IL-2R positive lymphomas.
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