Clinical characteristics, laboratory findings, and tolerance acquisition in infants with cow's milk protein allergy in a private center in Lima, Peru for the period 2021-2022

BACKGROUND

Cow's milk protein allergy (CMPA) remains relatively understudied in Latin America.

METHODS

In this observational study, we enrolled 64 patients with a median age of 3 months, of whom 60% were male. Patients included had a history of IgE-mediated reactions with IgE sensitization or non-IgE-mediated reactions or symptoms following exposure to cow's milk. They underwent skin prick test, ImmunoCAP, fecal calprotectin (FC), and fecal eosinophil-derived neurotoxin (EDN), in addition to double-blinded placebo-controlled oral food challenges (DBPCFC), with clinical evolution and tolerance acquisition observed over 1 year.

RESULTS

Malnutrition was present in 78.1% of patients, and 87.5% had a family history of atopy, with 51.6% receiving exclusive breastfeeding. Gastrointestinal manifestations were prevalent in 90.6% of patients, followed by dermatological manifestations (10.9%), with only 2 experiencing anaphylaxis. IgE-mediated CMPA was observed in only six patients. In those with non-IgE-mediated CMPA, FC had a median of 284 mg/dL (IQR: 138.5-415.5), while EDN had a median of 508.5 mg/dL (IQR: 160.25-868). One year after diagnosis, median FC significantly decreased (p < 0.0001), and malnutrition prevalence reduced to 17.1%. Moreover, 81% of patients acquired tolerance following DBPCFC, with 52% utilizing nutritional replacement formulas at diagnosis. Notably, 94% of those extensively hydrolyzed casein-based formulas achieved tolerance (p = 0.08).

CONCLUSION

Our findings provide a foundational framework for future investigations into CMPA diagnosis, tolerance acquisition, and the utilization of hypoallergenic formulas tailored to the unique characteristics of our region.

Chronic Milk-Dependent Food Protein-Induced Enterocolitis Syndrome in Children from West Pomerania Region

Characteristics of chronic milk-dependent food protein-induced enterocolitis syndrome (FPIES) in children from the region of Western Pomerania were studied. Prospectively, 55 children were diagnosed at a median of 2.2 months. The open food challenges (OFC), morphologies, milk-specific IgE (sIgE) (FEIA method, CAP system), and skin prick tests (SPTs) were examined. Vomiting and diarrhea escalated gradually but quickly led to growth retardation. Of the infants, 49% had BMI < 10 c, 20% BMI < 3 c; 25% had anemia, and 15% had hypoalbuminemia. During the OFCs we observed acute symptoms that appeared after 2-3 h: vomiting diarrhea and pallor. A total of 42% children required intravenous hydration. Casein hydrolysates or amino acids formulae (20%) were used in treatment. In 25% of children, SPT and milk sIgE were found, in 18%-other food SPTs, and in 14% allergy to other foods. A transition to IgE-dependent milk allergy was seen in 3 children. In the twelfth month of life, 62% of children had tolerance to milk, and in the twenty-fifth month-87%. Conclusions. Chronic milk-dependent FPIES resolves in most children. By the age of 2 children are at risk of multiple food sensitization, and those who have milk sIgE are at risk to transition to IgE-mediated milk allergy. Every OFC needs to be supervised due to possible severe reactions.

How Are Infants Suspected to Have Cow's Milk Allergy Managed? A Real World Study Report

The purpose of this study was to evaluate the diagnosis and management of infants presenting with symptoms attributable to cow’s milk allergy (CMA) in a real life setting and to test how the Cow’s Milk-related Symptom Score (CoMiSS^®) can be used to support the awareness to diagnose cow’s milk protein allergy in primary care practice. The CoMiSS is an awareness tool based on various symptoms such as crying, gastrointestinal symptoms, dermatological and respiratory symptoms. The study was conducted on 268 infants from four countries (Belgium, Czech Republic, Germany, UK) aged 0 to 18 months consulting for CMA related symptoms. The analysis was based on two visits of these subjects. The results show an average CoMiSS of 11 at the first visit. After a therapeutic dietary intervention, the score at the second visit, which happened 3 weeks ± 5 days after the first one, dropped to an average value of 4. A satisfaction questionnaire completed by the primary care practitioners suggested an overall high level of satisfaction with the application of the CoMiSS tool in routine practice. These data highlight a huge discrepancy in the diagnosis and management of infants suspected of CMA in the different countries. The findings suggest that the CoMISS questionnaire is an effective tool in aiding awareness of CMPA in primary health care.

Hydrolysed Formulas in the Management of Cow's Milk Allergy: New Insights, Pitfalls and Tips

An allergy to cow's milk requires the avoidance of cow's milk proteins and, in some infants, the use of a hypoallergenic formula. This review aims to summarize the current evidence concerning different types of hydrolysed formulas (HF), and recommendations for the treatment of IgE- and non-IgE-mediated cow's milk allergy and functional gastrointestinal disorders in infancy, for which some dietary intervention and HF may be of benefit to both immune and motor mechanisms. Current guidelines recommend cow's milk protein (i.e., whey or casein) extensively hydrolysed formula (eHF) as the first choice for cow's milk allergy treatment, and amino acid formulas for more severe cases or those with reactions to eHF. Rice hydrolysed formulas (rHF) have also become available in recent years. Both eHF and rHF are well tolerated by the majority of children allergic to cow's milk, with no concerns regarding body growth or adverse effects. Some hydrolysates may have a pro-active effect in modulating the immune system due to the presence of small peptides and additional components, like biotics. Despite encouraging results on tolerance acquisition, evidence is still not conclusive, thus hampering our ability to draw firm conclusions. In clinical practice, the choice of hypoallergenic formula should be based on the infant's age, the severity, frequency and persistence of symptoms, immune phenotype, growth pattern, formula cost, and in vivo proof of tolerance and efficacy.

Breast Milk: A Source of Functional Compounds with Potential Application in Nutrition and Therapy

Breast milk is an unbeatable food that covers all the nutritional requirements of an infant in its different stages of growth up to six months after birth. In addition, breastfeeding benefits both maternal and child health. Increasing knowledge has been acquired regarding the composition of breast milk. Epidemiological studies and epigenetics allow us to understand the possible lifelong effects of breastfeeding. In this review we have compiled some of the components with clear functional activity that are present in human milk and the processes through which they promote infant development and maturation as well as modulate immunity. Milk fat globule membrane, proteins, oligosaccharides, growth factors, milk exosomes, or microorganisms are functional components to use in infant formulas, any other food products, nutritional supplements, nutraceuticals, or even for the development of new clinical therapies. The clinical evaluation of these compounds and their commercial exploitation are limited by the difficulty of isolating and producing them on an adequate scale. In this work we focus on the compounds produced using milk components from other species such as bovine, transgenic cattle capable of expressing components of human breast milk or microbial culture engineering.

Cow's Milk Allergy or Gastroesophageal Reflux Disease-Can We Solve the Dilemma in Infants?

Cow's milk allergy (CMA) and gastro-esophageal reflux disease (GERD) may manifest with similar symptoms in infants making the diagnosis challenging. While immediate reaction to cow's milk protein indicate CMA, regurgitation, vomiting, crying, fussiness, poor appetite, sleep disturbances have been reported in both CMA and GERD and in other conditions such as functional gastrointestinal disorders, eosinophilic esophagitis, anatomic abnormalities, metabolic and neurological diseases. Gastrointestinal manifestations of CMA are often non-IgE mediated and clinical response to cow's milk free diet is not a proof of immune system involvement. Neither for non-IgE CMA nor for GERD there is a specific symptom or diagnostic test. Oral food challenge, esophageal pH impedance and endoscopy are recommended investigations for a correct clinical classification but they are not always feasible in all infants. As a consequence of the diagnostic difficulty, both over- and under- diagnosis of CMA or GERD may occur. Quite frequently acid inhibitors are empirically started. The aim of this review is to critically update the current knowledge of both conditions during infancy. A practical stepwise approach is proposed to help health care providers to manage infants presenting with persistent regurgitation, vomiting, crying or distress and to solve the clinical dilemma between GERD or CMA.

Effect of Low-Immunogenic Yogurt Drinks and Probiotic Bacteria on Immunoreactivity of Cow's Milk Proteins and Tolerance Induction-In Vitro and In Vivo Studies

There is no effective therapy for milk allergy. The role of lactic acid bacteria (LAB) and probiotics in protection against allergy-related outcomes is still under investigation. The aim of the study was to evaluate the immunomodulative and therapeutic potential of yogurt drinks in cow's milk allergy (CMA) management. We compared immunoreactivity of α-casein (α-CN), β-casein (β-CN), κ-casein (κ-CN), α-lactalbumin (α-LA), and β-lactoglobulin (β-LG) in 27 yogurt drinks fermented with different basic yogurt cultures, or yogurt cultures enriched with Lactobacillus plantarum and/or Bifidobacterium lactis strains, by competitive ELISA assay. Drinks with the lowest antigenic potential were used as allergoids for CMA therapy. BALB/c mice were sensitized via intraperitoneal injection of α-CN + β-LG mixture with aluminum adjuvant, and gavaged with increasing doses of selected low-immunogenic drinks (YM-basic, or YM-LB-enriched with L. plantarum and B. lactis) to induce tolerance. Milk- or phosphate-buffered saline (PBS)-dosed mice served as controls. Compared to milk, the immunoreactivity of proteins in drinks increased or decreased, depending on the bacterial sets applied for fermentation. Only a few sets acted synergistically in reducing immunoreactivity. The selected low-immunogenic drinks stimulated allergic mice for profiling Th2 to Th1 response and acquire tolerance, and the effect was greater with YM-LB drink, which during long-lasting interventional feeding strongly increased the secretion of regulatory cytokines, i.e., IL-10 and TGF-β, and IgA and decreased IL-4, IgE, and anti-(α-CN + β-LG) IgG1. The studies revealed variations in the potency of yogurt bacteria to change allergenicity of milk proteins and the need for their strict selection to obtain a safe product for allergy sufferers. The YM-LB drink with reduced antigenic potential may be a source of allergoids used in the immunotherapy of IgE mediated CMA, but further clinical or volunteer studies are required.

[Effect of maternal immune level at different pregnancy stages on cow's milk protein allergy in infants]

OBJECTIVE

To study the association between maternal Th1/Th2 immune level at different pregnancy stages and cow's milk protein allergy (CMPA) in infants.

METHODS

The healthy women with a singleton pregnancy, as well as their offspring, who attended Yidu Central Hospital of Weifang and Qingzhou Traditional Chinese Medicine Hospital from July 2016 to December 2018 were enrolled. The maternal levels of interleukin-2 (IL-2), interferon gamma (IFN-γ), interleukin-4 (IL-4), and interleukin-10 (IL-10) at the second and third trimesters of pregnancy were measured. A CMPA questionnaire survey was conducted within one year after birth. Food avoidance and cow's milk oral challenge tests were performed in infants suspected of CMPA. The 48 infants who met the diagnostic criteria for CMPA were included in the observation group, and the remaining 977 normal infants were included in the control group. A univariate analysis was performed on the infants with CMPA. A Poisson regression analysis was used to determine the association between maternal Th1/Th2 immune factors at different pregnancy stages and CMPA.

RESULTS

The detection rate of CMPA was 4.68%. The clinical manifestations included the symptoms of the digestive system, skin, and respiratory system and other symptoms. The univariate analysis showed that compared with the control group, the observation group had significantly higher incidence rates of maternal food allergy and maternal history of allergic diseases (P<0.05) and a significantly lower breastfeeding rate (P<0.05). The observation group had significantly lower maternal levels of IL-2 (second and third trimesters) and IFN-γ (third trimester) than the control group (P<0.05). Maternal low IFN-γ at the third trimester and maternal low IL-2 at the second and third trimesters were significantly associated with CMPA in infants (P<0.05). After correction of the factors of breastfeeding, maternal food allergy, and maternal history of allergic diseases, it was found that maternal low IL-2 and IFN-γ at the third trimester were still significantly associated with CMPA in infants (P<0.05).

CONCLUSIONS

The maternal decrease in Th1 level at the third trimester of pregnancy may lead to the change in fetal immunity and thus increase the risk of CMPA in offspring.

[Effect of maternal immune level at different pregnancy stages on cow's milk protein allergy in infants]

OBJECTIVE

To study the association between maternal Th1/Th2 immune level at different pregnancy stages and cow's milk protein allergy (CMPA) in infants.

METHODS

The healthy women with a singleton pregnancy, as well as their offspring, who attended Yidu Central Hospital of Weifang and Qingzhou Traditional Chinese Medicine Hospital from July 2016 to December 2018 were enrolled. The maternal levels of interleukin-2 (IL-2), interferon gamma (IFN-γ), interleukin-4 (IL-4), and interleukin-10 (IL-10) at the second and third trimesters of pregnancy were measured. A CMPA questionnaire survey was conducted within one year after birth. Food avoidance and cow's milk oral challenge tests were performed in infants suspected of CMPA. The 48 infants who met the diagnostic criteria for CMPA were included in the observation group, and the remaining 977 normal infants were included in the control group. A univariate analysis was performed on the infants with CMPA. A Poisson regression analysis was used to determine the association between maternal Th1/Th2 immune factors at different pregnancy stages and CMPA.

RESULTS

The detection rate of CMPA was 4.68%. The clinical manifestations included the symptoms of the digestive system, skin, and respiratory system and other symptoms. The univariate analysis showed that compared with the control group, the observation group had significantly higher incidence rates of maternal food allergy and maternal history of allergic diseases (P<0.05) and a significantly lower breastfeeding rate (P<0.05). The observation group had significantly lower maternal levels of IL-2 (second and third trimesters) and IFN-γ (third trimester) than the control group (P<0.05). Maternal low IFN-γ at the third trimester and maternal low IL-2 at the second and third trimesters were significantly associated with CMPA in infants (P<0.05). After correction of the factors of breastfeeding, maternal food allergy, and maternal history of allergic diseases, it was found that maternal low IL-2 and IFN-γ at the third trimester were still significantly associated with CMPA in infants (P<0.05).

CONCLUSIONS

The maternal decrease in Th1 level at the third trimester of pregnancy may lead to the change in fetal immunity and thus increase the risk of CMPA in offspring.

Peptide Release after Simulated Infant In Vitro Digestion of Dry Heated Cow's Milk Protein and Transport of Potentially Immunoreactive Peptides across the Caco-2 Cell Monolayer

Dry heating of cow’s milk protein, as applied in the production of “baked milk”, facilitates the resolution of cow’s milk allergy symptoms upon digestion. The heating and glycation-induced changes of the protein structure can affect both digestibility and immunoreactivity. The immunological consequences may be due to changes in the peptide profile of the digested dry heated milk protein. Therefore, cow’s milk protein powder was heated at low temperature (60 °C) and high temperature (130 °C) and applied to simulated infant in vitro digestion. Digestion-derived peptides after 10 min and 60 min in the intestinal phase were measured using LC-MS/MS. Moreover, digests after 10 min intestinal digestion were applied to a Caco-2 cell monolayer. T-cell epitopes were analysed using prediction software, while specific immunoglobin E (sIgE) binding epitopes were identified based on the existing literature. The largest number of sIgE binding epitopes was found in unheated samples, while T-cell epitopes were equally represented in all samples. Transport of glycated peptide indicated a preference for glucosyl lysine and lactosyl-lysine-modified peptides, while transport of peptides containing epitope structures was limited. This showed that the release of immunoreactive peptides can be affected by the applied heating conditions; however, availability of peptides containing epitopes might be limited.

Cytokine Expression by Human Macrophage-Like Cells Derived from the Monocytic Cell Line THP-1 Differs Between Treatment With Milk from Preterm- and Term-Delivering Mothers and Pasteurized Donor Milk

Immunomodulatory proteins from human milk may enhance the protection and development of the infant’s gut. This study compared the immunomodulatory effects of treatment with milk from preterm-(PM) and term-delivering (TM) mothers and pasteurized donor milk (DM) on cytokine gene expression in human macrophage-like cells derived from the monocytic cell line THP-1. The gene expression of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-12 (p40), IL-10 and GAPDH in macrophages treated with PM, TM and DM at steady and activated (inflammatory) states were measured using real-time reverse transcription-polymerase chain reaction. TNF-α and IL-6 in macrophages (both states) with DM were higher than PM or TM. IL-10 in steady state macrophages with DM was higher than PM whereas DM increased IL-10 in activated macrophages compared with TM. TM increased IL-6 and IL-12 (p40) in steady state macrophages compared with PM. IL-12 (p40) in activated macrophages with TM was higher than PM. IL-10 in steady state macrophages with TM was higher than PM. These results suggest that DM induces higher gene expression of pro-inflammatory and anti-inflammatory cytokines in macrophages compared with PM or TM. PM reduced gene expression of pro-inflammatory cytokines compared with TM, which may decrease the development of necrotizing enterocolitis and systematic inflammation.

Design, quality, safety and efficacy of extensively hydrolyzed formula for management of cow's milk protein allergy: What are the challenges?

Cow's milk protein allergy (CMPA) is one of the most common food allergies in infancy. Clinical food allergy guidelines recommend an extensively hydrolyzed formula (EHF) as the first-line treatment in nonbreastfed infants with CMPA. Designing and commercializing EHF poses both technical and regulatory challenges. Each manufacturing step, from sourcing of raw materials to release of the final product, needs to be managed in accordance with comprehensive quality systems. To avoid cross-contamination via externally sourced ingredients, suppliers should be carefully selected based on quality requirements. Strict zoning of the manufacturing areas according to contamination risk and air flow control are effective strategies to prevent accidental allergen contamination. Furthermore, dedicated manufacturing lines for hypoallergenic products are used to prevent potential cross-contamination from other products produced on the same line. The enzymatic hydrolysis, heat treatment and ultrafiltration used are specific to each manufacturer. Consequently, EHF are a heterogenous group of products with differences in the molecular weight profile of peptides, content of residual immunogenic cow's milk allergens, and residual in-vitro allergenicity. These differences are likely to affect clinical efficacy and safety. As not all commercialized EHF products have undergone formal testing in the laboratory and clinical trials, there is a need to develop guidelines for minimum technical and regulatory requirements for EHF products, including validated assays for ongoing quality control. Clinical trials assessing new EHF products for their hypoallergenicity and ability to support normal growth remain the definitive proof of efficacy and safety in infants and young children with CMPA.

Thermally-Induced Lactosylation of Whey Proteins: Identification and Synthesis of Lactosylated β-lactoglobulin Epitope

The high temperatures used in the production of milk may induce modifications in proteins structure. Due to occurrence of the Maillard reaction, lactose binds lysine residues in proteins, affecting the nutritional value. Milk is also an important source of allergenic proteins (i.e., caseins, β-lactoglobulin and α-lactalbumin). Thus, this modification may also affect the allergenicity of these proteins. Focusing on milk whey proteins, a screening on different Ultra High Temperatures (UHT) and pasteurized milk samples was performed to identify lactosylation sites, in particular in protein known epitopes, and to verify the correlation between lactosylation and the harshness of the treatment. Whey proteins were extracted from milk samples after caseins precipitations at pH 4.6 and, after chymotryptic and tryptic in solution digestion, peptides were analysed by UPLC-MS and LTQ-Orbitrap. Results show the presence of lactosylated lysine residues in several known epitopes. Then, a β-lactoglobulin epitope was selected and synthesized by solid phase synthesis followed by in solution lactosylation, obtaining high reaction yields and purities. The synthesis of lactosylated allergenic epitopes, described here for the first time, is a useful tool for further studies on the technological impacts on food allergenicity.

Predictors for late tolerance development in food protein-induced allergic proctocolitis

Background: Food protein-induced allergic proctocolitis (FPIAP) is a non-immunoglobulin E (IgE) mediated food allergy that typically presents with blood-mixed mucoid stool. Objective: To identify the predictors that affect the tolerance development in infants with FPAIP and laboratory as well as clinical differences between patients with early and with late tolerance. Methods: A total of 185 infants with FPIAP were included. The patients were grouped and analyzed based on laboratory tests and clinical characteristics. Results: The median (interquartile range [IQR]) age of onset of symptoms was 2.0 months (1.0-3.0 months). Symptoms began in severe cases in patients (n = 23) at a younger median (IQR) age (1.5 months [0.7-2.0 months]) than the group with nonsevere presentation (median 2.0 months [IQR 1.5-3.0 months]) (p < 0.001). The frequency of neutropenia (<1500/mm³) (p = 0.045) and eosinophilia (450 mm³) (p = 0.018) was increased in severe cases. Concomitant IgE-related food allergy (odds ratio [OR] 3.595 [95% confidence interval {CI}, 1.096-11.788], p = 0.035), non-IgE-mediated multiple food allergy (OR 3.577 [95% CI, 1.595-8.018], p = 0.002), feeding with cow's milk-based formula (at least once during infancy) (OR 2.517 [95% CI, 1.188-5.333], p = 0.016), and late complementary feeding (OR 5.438 [95% CI, 2.693-10.981], p < 0.001) were the predictors for late tolerance development. The estimated optimal cutoff value for introduction of complementary foods for the resolution of allergy was 5.5 months, with 69.4% sensitivity, 74.4% specificity, and an area under the curve of 0.737 (95% CI, 0.626-0.812) (p < 0.001). Conclusion: This study showed that the early introduction of complementary feeding accelerates tolerance development in FPAIP. A longer duration of an elimination diet has no impact on the resolution of allergy. Physicians should consider conservative avoidance measures and earlier introduction of complementary feeding in FPIAP.

The impact of immunomodulatory factors from maternal diet during pregnancy on cow's milk allergy in offspring - A pilot study in the paediatric population of the Kuyavian-Pomeranian Voivodship

BACKGROUND

The key role of dietary factors in immunotolerance promotion and allergic diseases prevention has been emphasised. The aim of the study was the analysis of the impact of immunomodulatory dietary components, consumed by pregnant women, on the development of cow's milk allergy (CMA) in their offspring.

MATERIALS AND METHODS

Fifty-one pairs of mothers and their CMA-offspring were included in the study group. The analysis of a daily intake of selected dietary components was conducted retrospectively with the application of a seven-day diet of a mother in the third trimester of gestation and the authors' own questionnaire. The Diet 5.D programme was used.

RESULTS

An average daily retinol intake by study-group mothers was significantly lower than by control-group mothers and valued 375.6μg/d vs. 543.7μg/d (p=0.040), respectively. Folates intake in the study group was 598.8μg/d vs. 361.1μg/d in the control group (p=0.001). Vitamin D in the study group was statistically lower - 3.6μg/d, comparing to the control group - 6.9μg/d (p=0.038). Average LC-PUFA intake by mothers with allergic children was 0.09g/d, while in the control group 0.18g/d (p=0.016). An analysis of the diet revealed that significantly more mothers of children from the control group (n=12; 48%) consumed fish 2-3 times per month in comparison to the study group (n=9; 17.6%) (p=0.007).

CONCLUSIONS

Vitamin D, A, LC-PUFA, retinol, riboflavin and fish consumption by pregnant mothers of CMA-children was significantly lower, whereas beta-carotene and folates consumption was significantly higher than that of mothers with non-allergic children.

First identification and characterization of a triple WAP domain containing protein in Procambarus clarkii provides new insights into the classification and evolution of WAP proteins in crustacean

Whey acidic protein domain (WAPD) is a usual motif in crustaceans, and is found mainly in the immune-related proteins. In the present study, a protein containing three tandem WAPDs was identified in red swamp crayfish Procambarus clarkii and designated as PcTWD. This is the first report of a protein of such domain architecture in crustaceans. Introducing the WAPDs of PcTWD into phylogenetic analysis led to the classification of crustacean WAP proteins into classical crustins and proteins containing solely WAPDs. PcTWD was widely expressed in multiple tissues, including hemocytes, gills, hepatopancreas, heart, stomach and intestine. Its expression could be significantly induced by Staphylococcus aureus or Aeromonas hydrophila challenge. Knockdown PcTWD expression by RNAi suppressed host resistance against A. hydrophila, while exogenous recombinant PcTWD could enhance the host immunity. The three WAPDs showed a labor division. The first two domains were responsible for the protease inhibitory activity, and the third domain contributed to the antimicrobial activity. Thus PcTWD was found as an important protein in crayfish antibacterial immunity.

Predicting outgrowth of IgE-mediated cow's milk allergy: Diagnostic tests in children under two years of age

BACKGROUND

Limited studies conducted on children <2 years old and/or involving a skin prick test (SPT) for fresh milk (FM) have examined the predictive value of allergometric tests for outgrowth of cow's milk allergy (CMA). We investigated the optimal decision points for outgrowth (ODP^fo) with SPT for commercial cow's milk extract (CE) and FM and specific immunoglobulin E (sIgE) levels for milk proteins to predict outgrowing allergy in children <2 years old.

METHODS

SPTs for CE and FM, tests for sIgEs (cow's milk, casein, α-lactoalbumin, β-lactoglobulin) and oral food challenges (OFC) were performed in children referred for evaluation of suspected CMA, and 15 months after diagnosis.

RESULTS

Fifty-one children (median age, 7.5 months; range, 2-23 months) were enrolled. Five had a history of anaphylaxis and 26 of 48 children with a positive initial challenge underwent milk elimination. The last OFC was performed in 28 children of whom 13 reacted to milk. The initial SPT responses to CE and FM and milk sIgE levels of the patients with persistent CMA were higher at diagnosis, with ODP^fo of 7mm, 9mm, and 10.5kU/L, respectively; these values remained higher with ODP^fo of 4mm, 11mm, and 10.5kU/L at the last OFC.

CONCLUSION

Higher initial SPTs for FM and CE and higher initial sIgE levels for cow's milk proteins are associated with a reduced likelihood of outgrowth. Initial milk sIgE level <10.5kU/L and initial SPT for fresh milk <9mm are related to the acquisition of tolerance in the follow-up period.

Reduced IgE and IgG antigenic response to milk proteins hydrolysates obtained with the use of non-commercial serine protease from Yarrowia lipolytica

The aim of the study was to investigate the use of serine protease from Yarrowia lipolytica yeast for reduction of milk proteins allergenicity. Whey protein concentrate (WPC-80), αs-casein and their hydrolysates were analyzed for the capacity to bind IgE and IgG antibodies present in sera from patients with cow milk protein allergy using a competitive ELISA. The hydrolysis of αs-casein and whey protein concentrate contributed to a significant reduction of their immunoreactive epitopes. In case of IgE antibodies, the lowest binding capacity was detected in the 24 h hydrolysates of both proteins in which the inhibition of the reaction was ≤20 and ≤68% for αs-casein and whey protein concentrate respectively. One hour hydrolysis of WPC-80 reduced the protein antigenicity, while the longer time (5 h) might lead to the exposure of new IgE - reactive epitopes.

Modulation of Milk Allergenicity by Baking Milk in Foods: A Proteomic Investigation

Cow's milk is considered the best wholesome supplement for children since it is highly enriched with micro and macro nutrients. Although the protein fraction is composed of more than 25 proteins, only a few of them are capable of triggering allergic reactions in sensitive consumers. The balance in protein composition plays an important role in the sensitization capacity of cow's milk, and its modification can increase the immunological response in allergic patients. In particular, the heating treatments in the presence of a food matrix have demonstrated a decrease in the milk allergenicity and this has also proved to play a pivotal role in developing tolerance towards milk. In this paper we investigated the effect of thermal treatment like baking of cow's milk proteins that were employed as ingredients in the preparation of muffins. A proteomic workflow was applied to the analysis of the protein bands highlighted along the SDS gel followed by western blot analyses with sera of milk allergic children in order to have deeper information on the impact of the heating on the epitopes and consequent IgE recognition. Our results show that incorporating milk in muffins might promote the formation of complex milk-food components and induce a modulation of the immunoreactivity towards milk allergens compared to milk baked in the oven at 180 °C for ten minutes. The interactions between milk proteins and food components during heating proved to play a role in the potential reduction of allergenicity as assessed by in vitro tests. This would help, in perspective, in designing strategies for improving milk tolerance in young patients affected from severe milk allergies.

Suppression of Food Allergic Symptoms by Raw Cow's Milk in Mice is Retained after Skimming but Abolished after Heating the Milk-A Promising Contribution of Alkaline Phosphatase

Raw cow's milk was previously shown to suppress allergic symptoms in a murine model for food allergy. In the present study, we investigated the contribution of fat content and heat-sensitive milk components to this allergy-protective effect. In addition, we determined the potency of alkaline phosphatase (ALP), a heat-sensitive raw milk component, to affect the allergic response. C3H/HeOuJ mice were treated with raw milk, pasteurized milk, skimmed raw milk, pasteurized milk spiked with ALP, or phosphate-buffered saline for eight days prior to sensitization and challenge with ovalbumin (OVA). Effects of these milk types on the allergic response were subsequently assessed. Similar to raw milk, skimmed raw milk suppressed food allergic symptoms, demonstrated by a reduced acute allergic skin response and low levels of OVA-specific IgE and Th2-related cytokines. This protective effect was accompanied by an induction of CD103⁺CD11b⁺ dendritic cells and TGF-β-producing regulatory T cells in the mesenteric lymph nodes. Pasteurized milk was not protective but adding ALP restored the allergy-protective effect. Not the fat content, but the heat-sensitive components are responsible for the allergy-protective effects of raw cow's milk. Adding ALP to heat-treated milk might be an interesting alternative to raw cow's milk consumption, as spiking pasteurized milk with ALP restored the protective effects.

Molecular Approaches for Diagnosis, Therapy and Prevention of Cow´s Milk Allergy

Cow´s milk is one of the most important and basic nutrients introduced early in life in our diet but can induce IgE-associated allergy. IgE-associated allergy to cow´s milk can cause severe allergic manifestations in the gut, skin and even in the respiratory tract and may lead to life-threatening anaphylactic shock due to the stability of certain cow´s milk allergens. Here, we provide an overview about the allergen molecules in cow´s milk and the advantages of the molecular diagnosis of IgE sensitization to cow´s milk by serology. In addition, we review current strategies for prevention and treatment of cow´s milk allergy and discuss how they could be improved in the future by innovative molecular approaches that are based on defined recombinant allergens, recombinant hypoallergenic allergen derivatives and synthetic peptides.

Prevention of Allergic Sensitization and Treatment of Cow's Milk Protein Allergy in Early Life: The Middle-East Step-Down Consensus

Allergy risk has become a significant public health issue with increasing prevalence. Exclusive breastfeeding is recommended for the first six months of life, but this recommendation is poorly adhered to in many parts of the world, including the Middle-East region, putting infants at risk of developing allergic sensitization and disorders. When breastfeeding is not possible or not adequate, a partially hydrolyzed whey formula (pHF-W) has shown proven benefits of preventing allergy, mainly atopic eczema, in children with a genetic risk. Therefore, besides stimulating breastfeeding, early identification of infants at risk for developing atopic disease and replacing commonly used formula based on intact cow milk protein (CMP) with a clinically proven pHF-W formula is of paramount importance for allergy prevention. If the child is affected by cow’s milk protein allergy (CMPA), expert guidelines recommend extensively hydrolyzed formula (eHF), or an amino acid formula (AAF) in case of severe symptoms. The Middle-East region has a unique practice of utilizing pHF-W as a step-down between eHF or AAF and intact CMP, which could be of benefit. The region is very heterogeneous with different levels of clinical practice, and as allergic disorders may be seen by healthcare professionals of different specialties with different levels of expertise, there is a great variability in preventive and treatment approaches within the region itself. During a consensus meeting, a new approach was discussed and unanimously approved by all participants, introducing the use of pHF-W in the therapeutic management of CMPA. This novel approach could be of worldwide benefit.

A Structured Gradual Exposure Protocol to Baked and Heated Milk in the Treatment of Milk Allergy

OBJECTIVE

To evaluate the efficacy and safety of a structured gradual exposure protocol (SGEP) with extensively heated and baked milk in promoting allergy resolution in children with cow milk allergy (CMA).

STUDY DESIGN

In a case control study, children with CMA aged 1-4 years who were treated with SGEP including extensively heated and baked milk, were compared with children treated with strict avoidance. Data were collected from medical records and from validated telephone questionnaires. Data analysis was performed using a nonparametric Kaplan-Meier and proportional hazard Cox regression model, after evaluation of the adequacy of the case control matching.

RESULTS

There were 43 children with milk allergy-26 (62%) males with a mean age at intervention of 21 months (range, 12-47 months)-who were treated with SGEP and followed to a mean age of 40 months (range, 20-82 months). The median age at resolution of CMA was compared with a matched group of 67 children treated with strict avoidance at least until 4 years of age or followed until earlier resolution, with a mean age at follow-up of 71 months (range, 11-176 months). The median estimated age at CMA resolution in the SGEP group was 36 months (95% CI, 34.5-49.7) compared with 98 months (95% CI, 82.4-114.1) in controls (P < .001). At last follow-up, 86% of treated children were tolerant to unheated milk proteins vs 52% of controls (P = .003).

CONCLUSION

A structured protocol with extensively heated and baked milk seems to promote faster resolution of CMA.

Cow's Milk Protein Allergy in Infancy: A Risk Factor for Functional Gastrointestinal Disorders in Children?

The role and prevalence of cow's milk protein allergy (CMA) in functional gastrointestinal disorders remains unclear. The aim of this review is to update knowledge on the relationship between CMA and functional abdominal pain disorders (FAPDs) in children. Cochrane Database and Pubmed were searched from inception using general and specific terms for CMA and functional gastrointestinal disorders. CMA is reported as a predisposing or coexisting factor in a wide range of functional gastrointestinal disorders in infants and children. Pathogenesis of both conditions is complex and multiple mechanisms including dysmotility and hypersensitivity might contribute to the clinical manifestations. Data supporting the possible role of food allergies in the pathogenesis of FAPDs are limited. CMA may predispose to early life inflammation and visceral hypersensitivity, which in turn might manifest as FAPDs. The diagnosis of either CMA or FAPDs and distinction between them is challenging because of nonspecific and overlapping symptoms. Lack of accurate allergy tests in non-IgE (immunoglobulin E) mediated cases is also problematic. Oral food challenge, following an elimination diet, should be performed to diagnose a suspected non-IgE CMA allergy in children with FAPDs. In the management of FAPDs, an elimination diet should be considered for a limited period to verify if the symptoms improve or resolve.

Prolonged breastfeeding and delayed introduction of whole cow's milk into the diet are factors associated with egg sensitization: A matched case-control study

BACKGROUND

Both breastfeeding and the moment at which introduction to solid food occurs have been associated with food allergy.

OBJECTIVE

To evaluate whether prolonged breastfeeding and the delayed introduction of whole cow's milk into an infant's diet are factors that can be associated with egg sensitization.

METHODS

This was a hospital-based case-control study, matched by age and sex: each study group comprised 97 atopic children. Additionally, logistic regression was used to identify the factors associated with egg protein sensitization.

RESULTS

The most common type of allergic disease among both groups was allergic rhinitis. After adjusting for possible confounding variables, a delayed introduction to whole cow's milk decreased the odds of egg protein sensitization; OR=0.16 (95% CI: 0.07-0.36, p<0.0001). Notably, breastfeeding during the first six months of life, regardless of whether it was the only milk an infant drank, increased the risk for sensitization to chicken eggs; OR=5.54 (95% CI: 2.41-12.7, p<0.0001).

CONCLUSION

Prolonged breastfeeding, regardless of whether it was the only milk an infant drank, greatly increased the risk of egg sensitization. Interestingly, a delayed introduction to whole cow's milk was associated with a reduced possibility of becoming sensitized to eggs. Further studies are required to elucidate these findings.

Electric Field Processing: Novel Perspectives on Allergenicity of Milk Proteins

Milk proteins are being widely used in formulated foods as a result of their excellent technological, functional, and biological properties. However, the most representative proteins from casein and whey fractions are also recognized as major allergens and responsible for the prevalence of cow's milk protein allergy in childhood. Electroheating technologies based on thermal processing of food as a result of application of moderate electric fields, also known by ohmic heating (OH) or Joule effect, are establishing a solid foothold in the food industry. Currently, the influence of OH on allergenic aspects of milk proteins is under debate but still undisclosed. The occurrence of electrical effects on the protein structure and its function has already been reported; thus, the impact of OH over allergenicity should not be overlooked. On the basis of these recent findings, it is then relevant to speculate about the impact of this emergent technology on the potential allergenicity of milk proteins.

[Association of FokI rs2228570 and TMPRSS6 rs855791 polymorphisms with cow's milk protein allergy in children]

OBJECTIVE

To study the association of polymorphisms of FokI rs2228570 in the vitamin D receptor (VDR) gene and TMPRSS6 rs855791 with cow's milk protein allergy (CMPA) in children.

METHODS

Quantitative real-time PCR was used to analyze the single nucleotide polymorphisms of FokI rs2228570 in the VDR gene and TMPRSS6 rs855791 in 100 children with CMPA and 100 healthy children (control group). The multivariate logistic regression model was used to identify the risk factors for CMPA.

RESULTS

There were significant differences in the frequencies of CC, CT, and TT genotypes of TMPRSS6 rs855791 between the CMPA and control groups (P=0.008), and the CMPA group had a significantly higher frequency of TT genotype. The multivariate logistic regression analysis showed that the children with TT genotype of rs855791 had an increased risk of CMPA (OR=3.473, P=0.011). However, there was no significant difference in the genotype distribution of FokI rs2228570 in the VDR gene between the two groups (P=0.686).

CONCLUSIONS

TMPRSS6 rs855791 polymorphism is associated with CMPA in children, and TT genotype may be the susceptible genotype of CMPA. FokI rs2228570 polymorphism is not associated with CMPA.

[Association of FokI rs2228570 and TMPRSS6 rs855791 polymorphisms with cow's milk protein allergy in children]

OBJECTIVE

To study the association of polymorphisms of FokI rs2228570 in the vitamin D receptor (VDR) gene and TMPRSS6 rs855791 with cow's milk protein allergy (CMPA) in children.

METHODS

Quantitative real-time PCR was used to analyze the single nucleotide polymorphisms of FokI rs2228570 in the VDR gene and TMPRSS6 rs855791 in 100 children with CMPA and 100 healthy children (control group). The multivariate logistic regression model was used to identify the risk factors for CMPA.

RESULTS

There were significant differences in the frequencies of CC, CT, and TT genotypes of TMPRSS6 rs855791 between the CMPA and control groups (P=0.008), and the CMPA group had a significantly higher frequency of TT genotype. The multivariate logistic regression analysis showed that the children with TT genotype of rs855791 had an increased risk of CMPA (OR=3.473, P=0.011). However, there was no significant difference in the genotype distribution of FokI rs2228570 in the VDR gene between the two groups (P=0.686).

CONCLUSIONS

TMPRSS6 rs855791 polymorphism is associated with CMPA in children, and TT genotype may be the susceptible genotype of CMPA. FokI rs2228570 polymorphism is not associated with CMPA.

Trichuris muris whey acidic protein induces type 2 protective immunity against whipworm

Human whipworm (Trichuris trichiura) infects approximately 1 in 15 people worldwide, representing the leading infectious cause of colitis and subsequent, inflammatory bowel disease (IBD). Current control measures focused on mass deworming have had limited success due to low drug efficacies. Vaccination would be an ideal, cost-effective strategy to induce protective immunity, leading to control of infection and transmission. Here we report the identification of whey acidic protein, a whipworm secretory protein, as a strong immunogen for inducing protective efficacy in a surrogate mouse T. muris infection model. The recombinant WAP protein (rTm-WAP49), as well as a single, highly conserved repeat within WAP (fragment 8) expressed as an Na-GST-1 fusion protein (rTm-WAP-F8+Na-GST-1), generate a strong T helper type 2 (Th2) immune response when delivered as subcutaneous vaccines formulated with Montanide ISA 720. Oral challenge with T. muris infective eggs following vaccination led to a significant reduction in worm burden of 48% by rTm-WAP49 and 33% by rTm-WAP-F8+Na-GST-1. The cellular immune correlates of protection included significant antigen-specific production of Th2 cytokines IL-4, IL-9, and IL-13 by cells isolated from the vaccine-draining inguinal lymph nodes, parasite-draining mesenteric lymph nodes, and spleen in mice vaccinated with either rTm-WAP49 or rTm-WAP-F8+Na-GST-1. The humoral immune correlates included a high antigen-specific ratio of IgG1 to IgG2a, without eliciting an IgE-mediated allergic response. Immunofluorescent staining of adult T. muris with WAP antisera identified the worm's pathogenic stichosome organ as the site of secretion of native Tm-WAP protein into the colonic mucosa. Given the high sequence conservation for the WAP proteins from T. muris and T. trichiura, the results presented here support the WAP protein to be further evaluated as a potential human whipworm vaccine candidate.

Low efficacy of atopy patch test in predicting tolerance development in non-IgE-mediated cow's milk allergy

BACKGROUND

The food atopy patch (APT) test has been used in previous studies to help the diagnosis of non-IgE mediated food allergies (FA). The aim of this study was to evaluate the efficacy of different cow's milk APT preparations to predict oral tolerance in children with previous non-IgE-mediated cow's milk allergy (CMA) diagnosis.

METHODS

Thirty-two patients non-IgE-mediated CMA diagnosed by oral food challenge (OFC) were enrolled to perform APT with three different cow's milk preparations (fresh, 2% in saline solution, 2% in petrolatum) and comparing with a new OFC after at least three months of diet exclusion.

RESULTS

Only six (18.7%) subjects presented positive OFC to cow's milk. No differences in gender, onset symptoms age, OFC age, Z-score, and exclusion period were found between positive and negative OFC patients. Preparations using fresh milk and powdered milk in petrolatum presented sensitivity equal to zero and specificity 92.3% and 96.1%. The preparation using powdered milk in saline solution showed sensitivity and specificity of 33.3% and 96.1%. Two patients presented typical IgE symptoms after OFC.

CONCLUSION

Cow's milk APT presented a low efficacy to predict tolerance in patients with previous non-IgE-mediated CMA and should not be used in clinical routine. The presence of typical IgE reactions after OFC hallmark the necessity of previous IgE-mediated investigation for this patient group.

Effects of two different domestic boiling practices on the allergenicity of cow's milk proteins

BACKGROUND

The sale of raw drinking milk through automatic dispensers is permitted in some EU member states, but consumers are usually advised to boil the milk before consumption. The present study has been conducted to evaluate the effects of two common domestic boiling techniques on the proteins of raw milk and, in particular, on their potential allergenicity.

RESULTS

Native one-dimensional electrophoresis, N-terminal amino acid sequencing and immunoblotting have been used to characterize the protein pattern and to evaluate the possible changes in the allergenic properties of the processed milk. The main result of this investigation is that heating induces the aggregation of β-lactoglobulin in higher-molecular-weight products, while caseins seem to be more resistant to the treatments. β-Lactoglobulin aggregates have been found to be non-immunoreactive with the sera of subjects suffering from cow's milk protein allergy.

CONCLUSION

Domestic boiling modifies the milk protein profile, causing a minor reduction in milk allergenicity. © 2017 Society of Chemical Industry.

Proteomics: a tool to develop novel diagnostic methods and unravel molecular mechanisms of pediatric diseases

Proteomics is the study of the expression of changes and post-translational modifications (PTM) of proteins along a metabolic condition either normal or pathological. In the field of health, proteomics allows obtaining valuable data for treatment, diagnosis or pathophysiological mechanisms of different illnesses. To illustrate the aforementioned, we describe two projects currently being performed at the Instituto Nacional de Pediatría: The immuno-proteomic study of cow milk allergy and the Proteomic study of childhood cataract. Cow's milk proteins (CMP) are the first antigens to which infants are exposed and generate allergy in some of them. In Mexico, the incidence of CMP allergy has been estimated at 5-7%. Clinical manifestations include both gastrointestinal and extra-gastrointestinal symptoms, making its diagnosis extremely difficult. An inappropriate diagnosis affects the development and growth of children. The goals of the study are to identify the main immune-reactive CMP in Mexican pediatric population and to design more accurate diagnostic tools for this disease. Childhood cataract is a major ocular disease representing one of the main causes of blindness in infants; in developing countries, this disease promotes up to 27% of cases related to visual loss. From this group, it has been estimated that close to 60% of children do not survive beyond two years after vision lost. PTM have been pointed out as the main cause of protein precipitation at the crystalline and, consequently, clouding of this tissue. The study of childhood cataract represents an outstanding opportunity to identify the PTM associated to the cataract-genesis process.

Fecal Microbiome and Food Allergy in Pediatric Atopic Dermatitis: A Cross-Sectional Pilot Study

BACKGROUND

Exposure to microbes may be important in the development of atopic disease. Atopic diseases have been associated with specific characteristics of the intestinal microbiome. The link between intestinal microbiota and food allergy has rarely been studied, and the gold standard for diagnosing food allergy (double-blind placebo-controlled food challenge [DBPCFC]) has seldom been used. We aimed to distinguish fecal microbial signatures for food allergy in children with atopic dermatitis (AD).

METHODS

Pediatric patients with AD, with and without food allergy, were included in this cross-sectional observational pilot study. AD was diagnosed according to the UK Working Party criteria. Food allergy was defined as a positive DBPCFC or a convincing clinical history, in combination with sensitization to the relevant food allergen. Fecal samples were analyzed using 16S rRNA microbial analysis. Microbial signature species, discriminating between the presence and absence food allergy, were selected by elastic net regression.

RESULTS

Eighty-two children with AD (39 girls) with a median age of 2.5 years, and 20 of whom were diagnosed with food allergy, provided fecal samples. Food allergy to peanut and cow's milk was the most common. Six bacterial species from the fecal microbiome were identified, that, when combined, distinguished between children with and without food allergy: Bifidobacterium breve, Bifidobacterium pseudocatenulatum, Bifidobacterium adolescentis, Escherichia coli, Faecalibacterium prausnitzii, and Akkermansia muciniphila (AUC 0.83, sensitivity 0.77, specificity 0.80).

CONCLUSIONS

In this pilot study, we identified a microbial signature in children with AD that discriminates between the absence and presence of food allergy. Future studies are needed to confirm our findings.

Single and multiple food allergies in infants with proctocolitis

BACKGROUND

Food protein-induced allergic proctocolitis is a frequent cause of rectal bleeding in infants. Characteristics of infants with multiple food allergies have not been defined.

OBJECTIVE

This study aimed to identify characteristics of infants with proctocolitis and compare infants with single and multiple food allergies.

METHODS

A total of 132 infants with proctocolitis were evaluated retrospectively. All of the infants were diagnosed by a paediatric allergist and/or a paediatric gastroenterologist according to guidelines. Clinical features of the infants, as well as results of a complete blood count, skin prick test, specific immunoglobulin E, and stool examinations or colonoscopy were recorded.

RESULTS

Cow's milk (97.7%) was the most common allergen, followed by egg (22%). Forty-five (34.1%) infants had allergies to more than one food. Infants with multiple food allergies had a higher eosinophil count (613±631.2 vs. 375±291.9) and a higher frequency of positive specific IgE and/or positive skin prick test results than that of patients with a single food allergy. Most of the patients whose symptoms persisted after two years of age had multiple food allergies.

CONCLUSIONS

There is no difference in clinical presentations between infants with single and multiple food allergies. However, infants with multiple food allergies have a high blood total eosinophil count and are more likely to have a positive skin prick test and/or positive specific IgE results.

[THE SERUM LEVELS OF MILK AND PEANUT-SPECIFIC IGE: ROLE IN THE EVALUATION OF THE RISK FOR ALLERGIC REACTION IN CHILDREN IN ISRAEL]

BACKGROUND

The performance characteristics of the ImmunoCAP assay for detecting specific IgE antibodies in the evaluation of milk and peanut allergy have been established. However, the results are not comparable to the IMMULITE 2000, another FDA-approved assay available in Israel, owing to differences in the extracts used, technical method, and population studied.

OBJECTIVES

To establish the performance characteristics and predictive values for the IMMULITE 2000 assay in Israel.

METHODS

The database of the Allergy Clinic at Schneider Children's Medical Center in Israel was searched for all patients referred for evaluation of allergies in 2006-2009. The results of the milk- and peanut-specific IgE antibody tests were collected and correlated with the clinical diagnoses of milk and peanut allergy or tolerance. Sensitivity, specificity and positive and negative predictive values were calculated as well as receiver operating characteristic (ROC) plots.

RESULTS

The prevalence of milk allergy was 30% (111/369 patients), and peanut allergy, 6% (31/505 patients). The area under the ROC curve was 0.954 for milk allergy and 0.956 for peanut allergy. The levels with a positive predictive value of ≥95% were 10 kU/L and 3 kU/L, respectively. The level of peanut-specific IgE antibodies with a ≥95% positive predictive value was lower than found for the ImmunoCAP in the USA and Europe.

CONCLUSIONS

These findings indicate that the decision points used for predicting the risk of future allergic reactions must be calculated separately for different assay methods and different populations. Our findings may assist the allergists in Israel to decide whether to perform a supervised oral challenge in order to verify if the patient has developed tolerance to milk or peanuts.

Characterization of a double WAP domain-containing protein from the red swamp crayfish Procambarus clarkii

Crustaceans express multiple whey acidic protein (WAP) domain containing proteins which are components of host immunity. In the present study, a new double WAP domain containing protein was identified from red swamp crayfish Procambarus clarkii, designated Pc-DWD. The ORF is 387 bp, encoding 128 amino acids consisting of signal peptide of 18 residues, and two tandem WAP domains of 38 and 44 residues. Multiple alignment indicates the presence of conserved motifs in both WAP domains, and phylogenetic analysis shows that Pc-DWD is a new member of the type-IV crustin family. Pc-DWD transcripts were found most abundantly in hemocytes, gills, intestine and heart, and induced by Vibrio anguillarum, Staphylococcus aureus and white spot syndrome virus challenge. RNAi knockdown of Pc-DWD expression led to increased expression of white spot syndrome virus genes and increased crayfish mortality after virus infection. Recombinant Pc-DWD exhibited strong protease inhibitory activity towards commercial subtilicin A and protease K. Pc-DWD inhibited the crude proteases from V. anguillarum and S. aureus cultures and from the crayfish tissue extracts. We infer that Pc-DWD acts in crayfish bacterial and viral immunity.

Microglial dysfunction as a key pathological change in adrenomyeloneuropathy

OBJECTIVE

Mutations in ABCD1 cause the neurodegenerative disease, adrenoleukodystrophy, which manifests as the spinal cord axonopathy adrenomyeloneuropathy (AMN) in nearly all males surviving into adulthood. Microglial dysfunction has long been implicated in pathogenesis of brain disease, but its role in the spinal cord is unclear.

METHODS

We assessed spinal cord microglia in humans and mice with AMN and investigated the role of ABCD1 in microglial activity toward neuronal phagocytosis in cell culture. Because mutations in ABCD1 lead to incorporation of very-long-chain fatty acids into phospholipids, we separately examined the effects of lysophosphatidylcholine (LPC) upon microglia.

RESULTS

Within the spinal cord of humans and mice with AMN, upregulation of several phagocytosis-related markers, such as MFGE8 and TREM2, precedes complement activation and synapse loss. Unexpectedly, this occurs in the absence of overt inflammation. LPC C26:0 added to ABCD1-deficient microglia in culture further enhances MFGE8 expression, aggravates phagocytosis, and leads to neuronal injury. Furthermore, exposure to a MFGE8-blocking antibody reduces phagocytic activity.

INTERPRETATION

Spinal cord microglia lacking ABCD1 are primed for phagocytosis, affecting neurons within an altered metabolic milieu. Blocking phagocytosis or specific phagocytic receptors may alleviate synapse loss and axonal degeneration. Ann Neurol 2017;82:813-827.

Identification of cross-reactive B-cell epitopes between Bos d 9.0101(Bos Taurus) and Gly m 5.0101 (Glycine max) by epitope mapping MALDI-TOF MS

Exposure to cow's milk constitutes one of the most common causes of food allergy. In addition, exposure to soy proteins has become relevant in a restricted proportion of milk allergic pediatric patients treated with soy formulae as a dairy substitute, because of the cross-allergenicity described between soy and milk proteins. We have previously identified several cross-reactive allergens between milk and soy that may explain this intolerance. The purpose of the present work was to identify epitopes in the purified αS1-casein and the recombinant soy allergen Gly m 5.0101 (Gly m 5) using an α-casein-specific monoclonal antibody (1D5 mAb) through two different approaches for epitope mapping, to understand cross-reactivity between milk and soy. The 1D5 mAb was immobilized onto magnetic beads, incubated with the peptide mixture previously obtained by enzymatic digestion of the allergens, and the captured peptides were identified by MALDI-TOF MS analysis. On a second approach, the peptide mixture was resolved by RP-HPLC and immunodominant peptides were identified by dot blot with the mAb. Finally, recognized peptides were sequenced by MALDI-TOF MS. This novel MS based approach led us to identify and characterize four peptides on α-casein and three peptides on Gly m 5 with a common core motif. Information obtained from these cross-reactive epitopes allows us to gain valuable insight into the molecular mechanisms of cross-reactivity, to further develop new and more effective vaccines for food allergy.

Oral immunotherapy for food allergy: A Spanish guideline. Immunotherapy egg and milk Spanish guide (items guide). Part I: Cow milk and egg oral immunotherapy: Introduction, methodology, rationale, current state, indications contraindications and oral immunotherapy build-up phase

INTRODUCTION

Cow's milk and egg are the most frequent causes of food allergy in the first years of life. Treatments such as oral immunotherapy (OIT) have been investigated as an alternative to avoidance diets. No clinical practice guides on the management of OIT with milk and egg are currently available.

OBJECTIVES

To develop a clinical guide on OIT based on the available scientific evidence and the opinions of experts.

METHODS

A review was made of studies published in the period between 1984 and June 2016, Doctoral Theses published in Spain, and summaries of communications at congresses (SEAIC, SEICAP, EAACI, AAAAI), with evaluation of the opinion consensus established by a group of experts pertaining to the scientific societies SEICAP and SEAIC.

RESULTS

Recommendations have been established regarding the indications, requirements and practical aspects of the different phases of OIT, as well as special protocols for patients at high risk of suffering adverse reactions.

CONCLUSIONS

A clinical practice guide is presented for the management of OIT with milk and egg, based on the opinion consensus of Spanish experts.

Storage of Unfed and Leftover Pasteurized Human Milk

OBJECTIVE

To determine the impact of storage on bacterial growth and immunological activity of pasteurized human milk and leftover pasteurized human milk that has been exposed to the microflora in an infant's mouth.

MATERIALS AND METHODS

Eighteen mother-infant dyads participated in two separate studies. Mother's milk was pasteurized, and each baby was fed 1 to 2 ounces. Pasteurized and leftover pasteurized milk were stored at room (24°C) and refrigerated temperatures (4°C). After storage, milk was analyzed for bacteria, total protein, lysozyme activity, and secretory immunoglobulin A (SIgA) activity.

RESULTS

In pasteurized and leftover pasteurized milk stored in the refrigerator for 7 days, total aerobic bacteria do not increase significantly and total protein and bioactive proteins are stable. At room temperature, there is a significant increase in total aerobic bacteria in leftover pasteurized milk during 12 hours of storage (p < 0.01) and a significant decrease in total protein and SIgA activity in pasteurized milk during 12 hours of storage (p = 0.02 and p = 0.03, respectively).

CONCLUSIONS

When stored in the refrigerator, pasteurized and leftover pasteurized milk may be stored for at least 7 days when considering the variables studied. Caution should be used when storing pasteurized and leftover pasteurized milk at room temperature to prevent an increase in bacterial growth and a decrease in total protein and SIgA activity.

Food allergy in breastfeeding babies. Hidden allergens in human milk

BACKGORUND

Food allergy is a rare disorder among breastfeeding babies.

OBJECTIVE

Our aim was to identify responsible allergens in human milk.

METHODS

We studied babies developing allergic symptoms at the time they were breastfeeding. Skin prick tests (SPT) were performed with breast milk and food allergens. Specific IgE was assessed and IgE Immunoblotting experiments with breast milk were carried out to identify food allergens. Clinical evolution was evaluated after a maternal free diet.

RESULTS

Five babies had confirmed breast milk allergy. Peanut, white egg and/or cow's milk were demonstrated as the hidden responsible allergens. No baby returned to develop symptoms once mother started a free diet. Three of these babies showed tolerance to other food allergens identified in human milk.

CONCLUSION

A maternal free diet should be recommended only if food allergy is confirmed in breastfed babies.

The Presence and Anti-HIV-1 Function of Tenascin C in Breast Milk and Genital Fluids

Tenascin-C (TNC) is a newly identified innate HIV-1-neutralizing protein present in breast milk, yet its presence and potential HIV-inhibitory function in other mucosal fluids is unknown. In this study, we identified TNC as a component of semen and cervical fluid of HIV-1-infected and uninfected individuals, although it is present at a significantly lower concentration and frequency compared to that of colostrum and mature breast milk, potentially due to genital fluid protease degradation. However, TNC was able to neutralize HIV-1 after exposure to low pH, suggesting that TNC could be active at low pH in the vaginal compartment. As mucosal fluids are complex and contain a number of proteins known to interact with the HIV-1 envelope, we further studied the relationship between the concentration of TNC and neutralizing activity in breast milk. The amount of TNC correlated only weakly with the overall innate HIV-1-neutralizing activity of breast milk of uninfected women and negatively correlated with neutralizing activity in milk of HIV-1 infected women, indicating that the amount of TNC in mucosal fluids is not adequate to impede HIV-1 transmission. Moreover, the presence of polyclonal IgG from milk of HIV-1 infected women, but not other HIV-1 envelope-binding milk proteins or monoclonal antibodies, blocked the neutralizing activity of TNC. Finally, as exogenous administration of TNC would be necessary for it to mediate measurable HIV-1 neutralizing activity in mucosal compartments, we established that recombinantly produced TNC has neutralizing activity against transmitted/founder HIV-1 strains that mimic that of purified TNC. Thus, we conclude that endogenous TNC concentration in mucosal fluids is likely inadequate to block HIV-1 transmission to uninfected individuals.

The Most Common Cow's Milk Allergenic Proteins with Respect to Allergic Symptoms in Iranian Patients

Cow's milk allergy (CMA) is an immunological response to cow's milk proteins such as casein, α-lactalbumin and β lactoglobulin. The aim of this study was to determine the most common cow's milk allergenic proteins in patients with CMA and identify the most effective proteins in different allergic symptoms. Eighty seven patients (≤18 years) with allergy to cow's milk from 2006 to 2013 entered this study. They had a positive history of allergic reactions to cow's milk and a positive specific IgE test to whole cow's milk. The patients' symptoms were divided into four groups. Serum specific IgEs against four different main proteins of cow's milk were measured using RIDA Allergy Screen. Among 87 patients, 53 (60.5%) were male and the median age was 2.5 years. The frequency of respiratory, skin, gastrointestinal symptoms, and anaphylaxis were 63.3%, 55.7%, 20.3%, and 13.4%, respectively. Specific IgEs to total cow's milk protein (n=75, 89.3%), and the main Cow's Milk Proteins including α-lactalbumin (n=65, 77.4%), casein (n=64, 75.3%), β-lactoglobulin (n=52, 62.7%), and bovine serum albumin (n=35, 44.9%) were detected. Specific IgE tests to β-lactoglobulin were positive in 90% of the patients with anaphylaxis. Moreover, significant relationship was found between specific IgE to β-lactoglobulin and anaphylaxis (p=0.04). Although it is presumed that α-lactalbumin and casein are the most common allergenic proteins of cow's milk, in this study there is a significant relationship between the anaphylaxis and the presence of β-lactoglobulin-specific IgE. Therefore, more precautions are recommended due to possible anaphylactic reactions in patients with a positive test history for β-lactoglobulin specific IgE.

[Clinical features of Eosinophilic Colitis in infants with persistent rectal bleeding]

The most common presentation of cow's milk protein allergy (CMP) in infants is known as eosinophilic colitis (EC). The aim of this study is to evaluate EC characteristics in infants evaluated with colonoscopy due to the presence of rectorrhagia.

PATIENTS AND METHODS

A retrospective case-control study. Left-sided colonoscopy records of infants with persistent rectal bleeding, conducted between January 2006 and March 2011, were reviewed. The cases corresponded to infants with rectal biopsy compatible with EC and controls with negative biopsy. Telephone questionnaires to parents were conducted, evaluating personal and family history.

RESULTS

Complete records were obtained in 61 (79%) of the 77 procedures. 33 (54%) of them were males. Examination average age was 6.3 ± 5.9 months. 25 (41%) patients had EC on their histology. Between cases and controls, no significant difference in gestational age, birth weight and gender, only regarding age at the time of rectal bleeding, were observed. There was also no difference in personal history regarding obstructive bronchitis, allergic rhinitis, family history of asthma, allergic rhinitis or other food allergies. Those who received artificial feeding did not presented greater risk of EC. The most common symptoms in the cases did not differ significantly from the controls.

CONCLUSIONS

The prevalence of EC in the children studied was 40.9%. Our results show that there are groups of patients with persistent rectal bleeding in which there is no personal or family history that helps diagnosing EC. An endoscopic study could be considered in these patients to establish a correct diagnosis of this condition, avoid unnecessary diets and not to delay the detection of other diseases.