Enhanced expression of endogenous retroviruses and of TRIM28 and SETDB1 in children with food allergy.

BACKGROUND: Human endogenous retroviruses (HERVs) represent 8% of our genome. They originate from ancestral infections and although no longer contagious they can regulate transcription of adjacent cellular genes, produce viral RNAs sensed as non-self by pattern recognition receptors, and encode viral proteins, such as Syncytin (SYN) 1 and 2, that exhibit potent immunomodulatory properties. Based on this, HERVs have been studied and proposed as relevant cofactors in several chronic inflammatory and immune-mediated diseases. HERV transcription is regulated by host TRIM28 and SET domain bifurcated histone lysine methyltransferase 1 (SETDB1), which in turn exert crucial regulatory functions on the host immune system. No studies explored the expression of HERVs, TRIM28, and SETDB1 in allergic patients. METHODS: We assessed, through a polymerase chain reaction real time Taqman amplification assay, the transcription levels of pol genes of HERV-H, HERV-K, HERV-W, and of env genes of SYN1 and SYN2, as well as of TRIM28 and SETDB1 in whole blood from 32 children with IgE-mediated food allergy, 19 with food protein-induced enterocolitis syndrome (FPIES), and in healthy control children. RESULTS: The expression levels of pol genes of HERV-H, -K, and -W were significantly enhanced in patients with IgE-mediated FA or FPIES as compared to control subjects, while the mRNA concentrations of SYN1 and SYN2 were comparable in each group of children. Both TRIM28 and SETDB1 mRNA levels were significantly higher in allergic patients. CONCLUSIONS: Given the influence of HERVs and of TRIM28 and SETDB1 on innate and adaptive immune responses, their transcriptional activation in children with food allergies suggest that they might play important roles in the development of these diseases.

Oleosin Cor a 15 is a novel allergen for Italian hazelnut allergic children.

BACKGROUND: Hazelnut allergy, which is characterized by symptoms that range from mild to severe, is one of the most common allergies in children throughout Europe, and an accurate diagnosis of this allergy is therefore essential. However, lipophilic allergens, such as oleosins, are generally underrepresented in diagnostic tests. We therefore sought to characterize the IgE reactivity of raw and roasted hazelnut oleosins, using the sera of hazelnut-allergic pediatric patients. METHODS: Raw and roasted hazelnut oil body-associated proteins were analyzed by means of 1D and 2D electrophoresis and MS. Oleosin IgE reactivity was assessed by immunoblotting with the sera of 27 children who have confirmed hazelnut allergies and from 10 tolerant subjects. A molecular characterization of the oleosins was performed by interrogating the C. avellana cv. Jefferson and cv. TGL genomes, and through expression and purification of the recombinant new allergen. RESULTS: A proteomic and genomic investigation allowed two new oleosins to be identified, in addition to Cor a 12 and Cor a 13, in hazelnut oil bodies. One of the new oleosins was registered as a new allergen, according to the WHO/IUIS Allergen Nomenclature Subcommittee criteria, and termed Cor a 15. Cor a 15 was the most frequently immunorecognized oleosin in our cohort. Oleosins resulted to be the only immunorecognized allergens in a subgroup of allergic patients who showed low ImmunoCAP assay IgE values and positive OFC and PbP. Hazelnut roasting resulted in an increase in oleosin immunoreactivity. CONCLUSION: A novel hazelnut oleosin, named Cor a 15, has been discovered. Cor a 15 could play a role in eliciting an allergic reaction in a subgroup of pediatric patients that exclusively immunorecognize oleosins. The high prevalence of hazelnut oleosin sensitization here reported further confirms the need to include oleosins in routine diagnostic procedures.

Camel milk: a possible alternative for children with cow's milk allergy?

BACKGROUND: Cow's milk protein allergy (CwMPA) is the most common food allergy during early childhood and its therapy consists in the elimination of cow's milk proteins (CwMP) from the diet and the introduction of alternative formulas. Evidence about clinical use of camel's milk (CM) in CwMPA in children is scarce. The aim of this study was to determine the entity of cross-sensitization between CM and CwM in children with CwMPA. METHODS: This prospective study was performed in children affected by CwMPA. We evaluated skin prick tests (SPT) for CwM, CwMP (alpha-lactalbumin [ALA], beta-lactoglobulin [BLG] and casein [CAS]) and CM and serum levels of CwM, ALA, BLG, CAS-sIgE. RESULTS: Sixty-seven children with CwMPA were included in this study: twenty-one resulted SPT+ to CM. Mean wheal diameters towards raw CwM, ALA, BLG and CAS resulted significantly larger in the CM SPT+ group than in the CM SPT- group (P<0.02). Likewise, mean IgE titers against CwM, ALA and CAS were significantly higher in the CM SPT+ group than in the CM SPT-group (P<0.01). The mean wheal diameter towards raw CwM was significantly larger than that towards CM (P<0.0001). CONCLUSIONS: This study confirms the presence of cross-sensitization between CwM and CM that remains lower if compared to other mammalian milks. Small wheals at the SPT towards CwM antigens together with low IgE titers against them could work as predictors in selecting patients that are expected to have negative CM SPT and then could be fed with CM with lower risks of allergic reactions.

Effect of hot air and infrared roasting on hazelnut allergenicity.

Roasting is known to affect the protein profile and allergenicity of hazelnuts (Corylus avellana cv TGL). The aim of the study was to investigate whether roasting techniques based on different heat transfer methods (hot air and infrared), differently affect the protein solubility and the IgE-binding capacities of both the soluble and insoluble hazelnut protein fractions. The immune-reactivity of the Cor a 9, Cor a 11 and Cor a 14 allergens resulted to be stable after roasting at 140 °C, for both types of treatment, while roasting at 170 °C caused a reduction in IgE-binding, which was particularly noticeable after infrared processing, that led to an almost complete disappearance of allergenicity. Microscopical analyses showed that roasting caused cytoplasmic network disruption, with a loss of lipid compartmentalization, as well as an alteration of the structure of the protein bodies and of the cell wall organization.

A 5-Month-Old Infant with Cardiorespiratory Arrest Caused by Food Protein-Induced Enterocolitis Syndrome to Cow's Milk Proteins.

Food protein-induced enterocolitis syndrome (FPIES) is a nonimmunoglobulin E cell-mediated food allergy, which occurs predominantly in infants and young children. The most commonly incriminated triggers are cow's milk (CM), soy, and grains. Acute FPIES can be potentially life-threatening and culminate in shock requiring fluid resuscitation in at least 15% of the cases. To our knowledge, there have been no reports in literature of cardiorespiratory arrest induced by acute FPIES. We describe the first case of cardiorespiratory arrest occurred after accidental ingestion of a CM-based formula in a 5-month-old infant with previous diagnosis of FPIES to CM.

Food protein-induced enterocolitis syndrome caused by fish and/or shellfish in Italy.

BACKGROUND: The study describes the demographic features, culprit foods, clinical features and outcomes for children presenting with acute fish and/or shellfish food protein-induced enterocolitis syndrome (FPIES) in four Italian paediatric allergy centres. METHODS: A retrospective/prospective study was undertaken. All children diagnosed with fish or shellfish FPIES were enrolled. The diagnosis of FPIES was based on Sicherer's or Miceli Sopo clinical criteria. Skin prick tests (SPT) were performed in all patients, at the time of diagnosis and prior to OFC. RESULTS: Seventy children were enrolled. Mean age at first episode was 14 months (range 6-46 months); mean age at diagnosis was 34 months (range 6-164 months). Sole and cod were the fish most commonly implicated. Fifty-seven of 70 (81%) children had FPIES exclusively to fish, 37 of 57 (65%) children had single-fish FPIES, 20 of 57 (35%) multiple-fish FPIES, nine of 70 (13%) presented adverse reactions exclusively to shellfish, and four of 70 (6%) presented adverse reactions to both fish and shellfish. Only four (5.7%) children presented episodes of acute FPIES with different foods (2 to cow's milk, 1 to egg, 1 to beef); in all cases, onset was prior to that of fish or shellfish FPIES. Fifteen of 70 (21%) children tolerated fish other than the offending fish. Twenty-four of 70 (34%) children achieved tolerance (age range 24-102 months). CONCLUSIONS: The chief peculiarities of acute fish and shellfish FPIES, compared to more frequent cow's milk or soy FPIES, are (i) later age of onset, (ii) longer persistence and (iii) possibility of tolerating fish other than the offending fish. Adverse reactions with shellfish are possible.

Clinical management of food protein-induced enterocolitis syndrome.

PURPOSE OF REVIEW: The article discusses the clinical management of patients affected by food protein-induced enterocolitis syndrome (FPIES), focusing on established therapeutic choices and future options. RECENT FINDINGS: After FPIES has been diagnosed and avoidance of the culprit food prescribed, the most important management needs are as follows. First, recurrence of acute FPIES episodes due to accidental ingestion of culprit food. It may be useful to give patients' families an action plan. The principal suggested treatments are intravenous fluids and steroids, whereas the use of epinephrine and ondansetron requires further study. In mild-to-moderate cases, oral rehydration should be sufficient. Second, dietary introduction of at-risk foods. In children with FPIES, in addition to that/those identified as culprit(s), some foods may not be tolerated (typically cow's milk, legumes, cereals, poultry). It has been suggested to avoid introducing these foods during the baby's first year. Otherwise, they may be given for the first time in hospital, performing an oral food challenge. Third, acquisition of tolerance. Children affected by cow's milk-FPIES have a good chance of acquiring tolerance by the time they reach age 18-24 months. For other culprit foods, insufficient data are available to indicate the appropriate time, so that it is suggested that an oral food challenge be performed about 1  year after the last acute episode. SUMMARY: Future clinical management of FPIES must take into account, among other factors, improved understanding of pathogenesis, possible detection of different phenotypes, and the introduction of more effective therapies for acute episodes. These factors will undoubtedly influence management decisions, which will become more diversified and effective.

Detailed proteomic analysis on DM: insight into its hypoallergenicity.

Successful therapy in cow milk (CM) protein allergy rests upon completely eliminating CM proteins from the child's diet: it is thus necessary to provide a replacement food. Donkey milk (DM) has recently aroused scientific and clinical interest, above all among paediatric allergologists. A deeper knowledge of proteins in DM is necessary to evaluate the immunological and physiological properties of this natural substitute for cow's milk. The paper offers a detailed comparative analysis among the protein fractions of DM, CM and human milk, following an extensive proteomic study of the casein and whey proteins of DM performed by narrow pH range 2-DE. The detailed protein composition and structural features reported in this study provide insight into the molecular reasons for the hypoallergenicity of DM. Whole DM might constitute a valid substitute of CM in feeding children with CM protein allergy and it might also constitute the basis for formulas suitable for allergic subjects in the first year of life.

Donkey's milk detailed lipid composition.

Donkey's milk (DM) has recently aroused scientific interest, above all among paediatric allergologists. A deeper knowledge of both proteins and fats in donkey's milk is necessary to evaluate the immunological, physiological and nutritional properties. By using the most refined techniques for fatty acids analysis, the paper offers a detailed comparative analysis of the lipid fractions of DM as well as of human and cow milk, also indicating the distribution of fatty-acid moieties among sn-1/3 and sn-2 positions of the glycerol backbone. In DM the position of fatty acids on glycerol backbone, above all of long chain saturated fatty acids, is very similar to that of human milk: this fact, in conjunction with the relatively high contents of medium-chain triglycerides, makes the lipids in DM, through quantitatively reduced, highly bioavailable. The high PUFA n-3 content of donkey's milk, and especially its low n-6/n-3 ratio, acquires particular interest in subjects affected by cow's milk protein allergy. Whole DM might also constitute the basis for formulas suitable for subjects in the first year of life.

Multiple bone fractures in an 8-year-old child with cow's milk allergy and inappropriate calcium supplementation.

The case of an 8-year-old boy with severe bone mass reduction and 4 fractures as a result of an unsupervised diet established to treat cow's milk allergy is presented. Endocrine, genetic and orthopedic pathologies were excluded. While vitamin D intake had always been appropriate, his calcium intake had been inadequate for many years. This clinical report suggests that both vitamin D and calcium supplementation are necessary when a cow's milk protein-free diet is prescribed, even when a hypo- or non-allergenic formula is provided.

Efficacy of donkey's milk in treating highly problematic cow's milk allergic children: an in vivo and in vitro study.

Successful therapy in cow's milk protein allergy rests on completely eliminating cow's milk proteins from the child's diet: it is thus necessary to provide a replacement food. This prospective study investigated tolerance of donkey's milk in a population of 46 selected children with cow's milk protein allergy, for whom it was not possible to use any cow's milk substitute. Thirty-eight children (82.6%) liked and tolerated donkey's milk at the challenge and for the entire duration of follow-up. Catch-up growth was observed in all subjects with growth deficit during cow's milk proteins challenge. The degree of cross-reactivity of immunoglobulin E (IgE) with donkey's milk proteins was very weak and aspecific. Donkey's milk was found to be a valid alternative to both IgE-mediated and non-IgE-mediated cow's milk proteins allergy, including in terms of palatability and weight-height gain.

Relationship between maternal- and fetal-specific IgE.

AIM: A positive correlation between maternal and cord-blood IgE levels is well documented for total IgEs, but not for specific IgEs. The difficulty in detecting specific cord-blood IgEs is due to their low concentrations, which hinder their dosage by low-sensitivity methods. The study aimed to correlate maternal and foetal specific IgEs against individual cow's milk proteins, detected by highly sensitive and specific techniques. METHODS: Cow's milk specific IgE detection was performed by chemiluminescence on 52 specimens of maternal and cord blood after cow's milk protein separation by 1D and 2D gel electrophoresis. Cow's milk protein (CMP) antigens were identified by mass spectrometry techniques. RESULTS: Specific IgEs for CMPs were found in 25/52 (48.1%) of maternal sera and in 19/52 (37%) of cord-blood sera. In order of decreasing frequency, the proteins found were BSA, IgG heavy chain, caseins and, in a single case, b-lactoglobulin. Positive cord-blood sera in all cases corresponded to a positive maternal result, and maternal and foetal immunoreactivity patterns were closely correlated. Moreover, in no case was there a positive cord-blood response with a negative maternal response. CONCLUSION: The study demonstrates a close relationship between maternal and cord-blood specific IgE patterns. The phenomenon observed could provide a model to elucidate the general production method of foetal IgEs, which might only be produced in the presence of both the corresponding maternal IgE and the related allergen.

Z-score of weight for age of infants with atopic dermatitis and cow's milk allergy fed with a rice-hydrolysate formula during the first two years of life.

BACKGROUND: Recently, rice-based formulas have been widely used in hypoallergenic diets, but data on nutritional values are scarce. AIM: To evaluate the growth of infants fed with a rice-based hydrolysate formula, compared to those infants fed with a soy formula or an extensively hydrolysed casein formula, in the first 2 y of life. METHODS: A total of 88 infants were enrolled between March 2002 and March 2004. Fifty-eight infants with atopic dermatitis (AD) and cow's milk allergy (CMA), confirmed by open challenge, were enrolled as study group: 15 were fed with a rice-based hydrolysate formula (RHF), 17 with a soy-based formula (SF) and 26 with an extensively hydrolysed casein formula (eHCF). Thirty infants with AD without cow's milk allergy were recruited as a control group (CG) and fed with a free diet. Weight was recorded on enrolment and at 3-monthly intervals in the first year of life, and at 6-monthly intervals in the second year. Infants were weighed naked, before feeding, by means of an electronic integrating scale. The z-scores of weight for age were calculated. STATISTICS: One-way analysis of variance and Student's t-test were used for statistical comparison. Significance was set at p<0.05. RESULTS: No significant differences between the RHF, SF and eHCF groups were observed for the z-score of weight for age during the first 2 y of life, but a significantly lower difference was seen in the RHF group compared to the control group in the intervals 9 mo-1 y (p=0.025) and 1-1.5 y (p=0.020) of age. In contrast, the SF and eHCF groups were comparable to the control group, but the eHCF group was significantly lower (p=0) in the first trimester of life. CONCLUSION: Even if our findings show no significant difference between RHF and control, low weight observed in infants fed with RHF raises doubts about the nutritional adequacy of rice-hydrolysate formulas.

Cow's milk allergens identification by two-dimensional immunoblotting and mass spectrometry.

Cow's milk allergy (CMA) has become a common disease in early childhood, its prevalence ranging from 1.6% to 2.8% among children younger than 2 years of age. The role of different cow's milk protein (CMP) in the pathogenesis of CMA is still controversial. Even if the proteins most frequently and most intensively recognized by immunoglobulin E (IgE) seem to be the most abundant in milk (caseins and beta-lactoglobulin), with an although great variability all milk proteins appear to be potential allergens, even those that are present in trace amounts (i.e., lactoferrin, IgG, and BSA). In this work proteomics techniques have been applied for CMP allergens analysis. Allergens have been identified by immunoblotting following resolution of CMP components by two-dimensional electrophoresis. Sera from 20 milk-allergic subjects, as proven by oral provocation test, CAP-RAST and skin prick test, have been used for cow's milk major allergen identification. Cow's milk proteins and their isoforms were identified by matrix assisted laser desorption/ionization-time of flight (MALDI-TOF)-mass spectrometry. In our group of patients, the prevalence of CMP allergens, i.e., the total number of subjects sensitized to CMP divided by the total number of the subjects enrolled in the study, was: 55% alpha(s1)-casein, 90% alpha(s2)-casein, 15% beta-casein, 50% kappa-casein, 45% beta-lactoglobulin, 45% BSA, 95% IgG-heavy chain, 50% lactoferrin, and 0% alpha-lactalbumin.