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Biomedical subjects

J M Wal

Publications and source records attributed to J M Wal.

At least 19 recordsLinked to original sources
PubMed2006

Gastro-duodenal digestion products of the major peanut allergen Ara h 1 retain an allergenic potential.

BACKGROUND: The process of gastro-duodenal digestion may play a role in determining the allergenic properties of food proteins. The sensitizing and allergenic potential of digestion products of highly degraded allergens, such as the major peanut allergen Ara h 1, is currently under debate. We evaluated the effect of in vitro gastro-duodenal digestion of Ara h 1 on T cell reactivity and basophil histamine release. METHODS: An in vitro model of gastro-duodenal digestion was used to investigate changes in the allergenic properties of Ara h 1 using in vitro assays monitoring T cell reactivity (proliferation, cytokine production) and histamine release of basophils from peanut allergic individuals. The digestion process was monitored using an SDS-PAGE gel. RESULTS: In vitro gastric digestion led to rapid degradation of Ara h 1 into small fragments M(r) L5600. Gastric digestion did not affect the ability of Ara h 1 to stimulate cellular proliferation. Gastro-duodenal digestion significantly reduced its ability to stimulate clonal expansion (P<0,05; Wilxocon's signed rank test). The Th-2 type cytokine polarization of T cells from peanut allergic donors (IFN-gamma/IL-13 ratio and IFN-gamma/IL-4 ratio of CFSE(low) CD4(+) T cells) remained unchanged regardless of the level of digestion. Histamine release of basophils from peanut allergic individuals was induced to the same extent by native Ara h 1 and its digestion products. CONCLUSION: Gastro-duodenal digestion fragments of Ara h 1 retain T cell stimulatory and IgE-binding and cross-linking properties of the intact protein.

Allergens↗
PubMed2006

Allergy to goat and sheep milk without allergy to cow's milk.

BACKGROUND: Cow's milk (CM) allergy is the most frequent cause of food allergy in infants. Most children who are allergic to CM are also sensitized to whey proteins and/or to the casein fraction and many of them cannot tolerate goat's or sheep's milk (GSM) either. Conversely, the GSM allergies that are not associated with allergic cross-reactivity to CM are rare. METHODS: Twenty-eight children who had severe allergic reactions, including anaphylaxis, after consumption of GSM products but tolerated CM products were recruited in a retrospective study. Whole casein and whey proteins were fractionated from CM and GSM. beta-Lactoglobulin and the different caseins were isolated, purified and used to perform enzyme allergosorbent tests (EAST) and EAST inhibition studies with the sera of the allergic children. RESULTS: Clinical observations, skin prick testing and immunoglobulin (Ig)E-binding studies confirmed the diagnosis of GSM allergy without associated CM allergy. EAST determinations demonstrated that GSM allergy involves the casein fraction and not whey proteins. Cow's milk caseins were not at all or poorly recognized by the patient's IgE, while alphaS(1)-, alphaS(2)- and beta-caseins from GSM were recognized with a high specificity and affinity. In all cases, increasing concentrations of CM caseins failed to inhibit the binding of patient's IgE to sheep or goat milk caseins, whereas this binding was completely inhibited by GSM caseins. CONCLUSIONS: The characteristics of GSM allergy differ from those of the CM allergy because it affects older children and appears later. CM products do not elicit any clinical manifestation in GSM allergic patients, whereas CM allergic patients, usually cross-react to GSM. In all the GSM allergic children, the IgE antibodies recognized the caseins but not the whey proteins. Moreover, IgE specificity and affinity was high to GSM and lower to CM caseins despite their marked sequence homology. Doctors and allergic individuals should be aware that GSM allergy requires a strict avoidance of GSM and milk-derived products because reactions could be severe after ingestion of minimal doses of the offending food.

Adolescent↗
PubMed2005

Influence of thermal processing on the allergenicity of peanut proteins.

Peanuts are one of the most common and severe food allergens. Nevertheless, the occurrence of peanut allergy varies between countries and depends on both the exposure and the way peanuts are consumed. Processing is known to influence the allergenicity of peanut proteins. The aim of this study was to assess the effect of thermal processing on the IgE-binding capacity of whole peanut protein extracts and of the major peanut allergens Ara h 1 and Ara h 2. Whole proteins, Ara h 1, and Ara h 2 were extracted and purified from raw, roasted and boiled peanuts using selective precipitation and multiple chromatographic steps, and were then characterized by electrophoresis and mass spectrometry. The immunoreactivity of whole peanut extracts and purified proteins was analyzed by the enzyme allergosorbent test (EAST) and EAST inhibition using the sera of 37 peanut-allergic patients. The composition of the whole protein extracts was modified after heat processing, especially after boiling. The electrophoretic pattern showed protein bands of low molecular weight that were less marked in boiled than in raw and roasted peanuts. The same low-molecular-weight proteins were found in the cooking water of peanuts. Whole peanut protein extracts obtained after the different processes were all recognized by the IgE of the 37 patients. The IgE-binding capacity of the whole peanut protein extracts prepared from boiled peanuts was 2-fold lower than that of the extracts prepared from raw and roasted peanuts. No significant difference was observed between protein extracts from raw and roasted peanuts. It is noteworthy that the proteins present in the cooking water were also recognized by the IgE of peanut-allergic patients. IgE immunoreactivity of purified Ara h 1 and Ara h 2 prepared from roasted peanuts was higher than that of their counterparts prepared from raw and boiled peanuts. The IgE-binding capacity of purified Ara h 1 and Ara h 2 was altered by heat treatment and in particular was increased by roasting. However, no significant difference in IgE immunoreactivity was observed between whole protein extracts from raw and roasted peanuts. The decrease in allergenicity of boiled peanuts results mainly from a transfer of low-molecular-weight allergens into the water during cooking.

2S Albumins, Plant↗
PubMed2005

Improvement of bovine beta-lactoglobulin production and secretion by Lactococcus lactis.

The stabilizing effects of staphylococcal nuclease (Nuc) and of a synthetic propeptide (LEISSTCDA, hereafter called LEISS) on the production of a model food allergen, bovine beta-lactoglobulin (BLG), in Lactococcus lactis were investigated. The fusion of Nuc to BLG (Nuc-BLG) results in higher production and secretion of the hybrid protein. When LEISS was fused to BLG, the production of the resulting protein LEISS-BLG was only slightly improved compared to the one obtained with Nuc-BLG. However, the secretion of LEISS-BLG was dramatically enhanced (approximately 10- and 4-fold higher than BLG and Nuc-BLG, respectively). Finally, the fusion of LEISS to Nuc-BLG resulting in the protein LEISS-Nuc-BLG led to the highest production of the hybrid protein, estimated at approximately 8 microg/ml (approximately 2-fold higher than Nuc-BLG). In conclusion, the fusions described here led to the improvement of the production and secretion of BLG. These tools will be used to modulate the immune response against BLG via delivery of recombinant lactococci at the mucosal level, in a mouse model of cow's milk allergy.

Animals↗
PubMed2004

Assessment of the safety of foods derived from genetically modified (GM) crops.

This paper provides guidance on how to assess the safety of foods derived from genetically modified crops (GM crops); it summarises conclusions and recommendations of Working Group 1 of the ENTRANSFOOD project. The paper provides an approach for adapting the test strategy to the characteristics of the modified crop and the introduced trait, and assessing potential unintended effects from the genetic modification. The proposed approach to safety assessment starts with the comparison of the new GM crop with a traditional counterpart that is generally accepted as safe based on a history of human food use (the concept of substantial equivalence). This case-focused approach ensures that foods derived from GM crops that have passed this extensive test-regime are as safe and nutritious as currently consumed plant-derived foods. The approach is suitable for current and future GM crops with more complex modifications. First, the paper reviews test methods developed for the risk assessment of chemicals, including food additives and pesticides, discussing which of these methods are suitable for the assessment of recombinant proteins and whole foods. Second, the paper presents a systematic approach to combine test methods for the safety assessment of foods derived from a specific GM crop. Third, the paper provides an overview on developments in this area that may prove of use in the safety assessment of GM crops, and recommendations for research priorities. It is concluded that the combination of existing test methods provides a sound test-regime to assess the safety of GM crops. Advances in our understanding of molecular biology, biochemistry, and nutrition may in future allow further improvement of test methods that will over time render the safety assessment of foods even more effective and informative.

Animals↗
PubMed2004

[Animal models for assessment of GMO allergenicity: advantages and limitations].

Incidence of IgE-mediated allergic reactions to foods is increasing as well as the severity of associated symptoms and numerous foods are now incriminated, probably in relation with modifications of dietary habits and increased exposure to new or modified food ingredients. Therefore, the introduction on the market of food composed of or derived from genetically modified organisms (GMOs) raised the question of their potential allergenicity. Particularly with regards to the allergenicity of a newly expressed protein, it is necessary to obtain, from several steps in the risk assessment process, a cumulative body of evidence which minimises any uncertainty. This may include the use of animal model despite no fully reliable validated model is available yet. Such animal models should allow to address 3 major issues: Is the novel protein a sensitizer, i.e. does it possess intrinsic properties that allow to sensitize a predisposed individual? Is the protein an elicitor i.e. is it able to elicit an allergic reaction in a sensitised individual? And is the protein an adjuvant, i.e. can it facilitate or enhance the sensitisation to an other protein? Animal models under investigation currently include mice, rats and guinea pigs but models such as dogs and swine also appeared a few years ago. The aim is to mimic the mechanism and characteristics of the sensitisation phase and/or the elicitation phase of the allergic reaction as it occurs in atopic humans. They are necessary because sensitisation studies can obviously not be done in human and because in vitro tests cannot reproduce the complexity of the immune system. We propose a mouse model which mimics both phases of the allergic reaction. It has permitted to evidence that biochemical and clinical manifestations occuring during the active phases of the allergic reaction differ according to the structure of the allergen used for the challenge. This may allow to compare the allergenic potential of a genetically modified protein with that of the conventional one and to identify possible unintended effects. However, pathogenesis of food allergy in human is very complex and multifactorial, including individual differences in susceptibility, environmental factors, conditions of exposure, ... No animal model can take into account all these factors and allow a reliable prediction of the prevalence and severity of allergic reactions which would result from the exposure to a (novel) protein. Nevertheless, point by point analysis using the different models available may provide useful informations on the potential allergenicity of a novel protein.

Adjuvants, Immunologic↗
PubMed2003

Polygalacturonase (pectinase), a new oilseed rape allergen.

BACKGROUND: Type I hypersensitivity to rapeseed pollen allergens was described as the result of a cross-sensitization with various pollens that could constitute an aggravating factor in birch or grass pollen allergies. Recently, a few rapeseed pollen allergens were described. The aim of the present work was to identify new rapeseed pollen allergens by using two-dimensional gel analysis, microsequencing, and mass spectrometry. METHODS: Water extractable proteins from oilseed rape pollen or stamen were separated by two-dimensional gel electrophoresis. The proteins were then electroblotted onto a nitrocellulose (NC) sheet. The NC sheets were successively incubated with (1) individual human sera pre-selected for their immunoglobulin E (IgE) reactivity to rapeseed pollen proteins, (2) alkaline phosphatase (AP)-conjugated goat anti-human IgE and (3) AP substrate. The allergens localized by this method were then identified by microsequencing and MALDI-TOF mass spectrometry analysis. RESULTS: Of the 18 sera studied, five recognized a wide multispot zone with a molecular mass around 43 kD and pIs between 6.5 and 8.5. The results obtained with two representative sera are shown. From this zone, two isoforms of the polygalacturonase enzyme were identified by microsequencing. Confirmation was obtained through MALDI-TOF mass spectrometry analysis. CONCLUSION: The present results allow the identification of a new rapeseed allergen that can be the main allergen for some patients.

Allergens↗
PubMed2003

Serological characteristics of peanut allergy in children.

BACKGROUND: Food challenge is considered an excellent clinical tool for the diagnosis of specific food allergy. However in the case of peanut allergy it may be difficult to perform because of the severity of the reactions. The quantitation of a specific immunoglobulin E (IgE) response to different peanut allergens could also contribute to the improvement of the diagnosis. We characterized the IgE response to a whole peanut protein extract and to Ara h 1 and Ara h 2 in different groups of patients classified according to the severity of their allergic reactions. METHODS: Specific serum IgE were analyzed in 96 children by enzyme-linked immunosorbent assay tests using a whole protein extract or purified peanut proteins and anti-human IgE monoclonal antibodies labeled with acetylcholinesterase. RESULTS: A parallel was observed between levels of peanut-specific IgE and the classification in five groups and subgroups of patients upon increasing severity of symptoms, especially within the group of highest severity. Moreover, the highest frequency of positive response and the highest levels of specific IgE were observed with whole peanut protein extract. CONCLUSION: In a retrospective evaluation of peanut allergy in children, we have shown that quantitation of peanut-specific IgE could be used to avoid a food challenge particularly in the case of severe reactions. When compared to Ara h 1 and Ara h 2, whole peanut protein extract appeared to be the most appropriate allergen to perform the test.

2S Albumins, Plant↗
PubMed2003

Detection of caseinophosphopeptides in the distal ileostomy fluid of human subjects.

Caseinophosphopeptides (CPP) were detected for the first time in ileostomy fluid, collected at 2 h intervals for 10 h post milk and CPP ingestion, from human volunteers with an ileostomy. The level of CPP present in ileostomy fluid obtained from milk-fed volunteers was markedly higher than that from volunteers fed with selected CPP preparations. The findings are based on HPLC analysis in combination with peptide-bound P determination, thin-layer electrophoresis and amino acid analysis, together with ELISA studies using polyclonal antibodies raised against a set of CPP to detect immunoreactive CPP in ileostomy fluid. These procedures allowed the detection of nm concentrations of CPP. CPP, which can be released during intestinal digestion, may function as bioactive constituents and carriers for different minerals, especially Ca, and may be used as ingredients in functional foods or pharmaceutical preparations.

Adult↗
PubMed2003

Lipid transfer protein 1 is a possible allergen in Arabidopsis thaliana.

BACKGROUND: The Arabidopsis thaliana genome was recently fully sequenced, and this plant is now considered as the most useful model to study the effects of genetic engineering. The aim of the present study was to identify A. thaliana IgE-binding molecules and to localize their genes in order to evaluate the potential effect of gene insertion on the expression of IgE-binding molecules. METHODS: A. thaliana flower proteins were separated by two-dimensional gel electrophoresis and transferred onto a nitrocellulose sheet. The nitrocellulose sheet was successively incubated with human sera known to contain IgE that binds to rapeseed proteins, alkaline phosphatase-conjugated goat anti-human IgE and 5-bromo-4-chloro-3-indolyl phosphate and nitroblue tetrazolium. One allergen was further identified by N-terminal amino acid microsequencing. RESULTS: The results showed that some individuals possessed IgE that recognized numerous proteins with high molecular masses and various isoelectric points. This binding pattern strongly suggests that the epitopes recognized by these IgE could be, at least partly, sugar residues. Otherwise, out of the 10 sera that possessed IgE to Arabidopsis flower proteins, one serum strongly recognized a unique basic protein with an apparent molecular mass of around 14 kD. This protein was identified by amino acid microsequencing as the lipid transfer protein 1 (LTP1). CONCLUSION: We have demonstrated that A. Thaliana LTP1 is IgE reactive. The gene encoding this protein is located on chromosome 2, but it has been described that family 1 of A. Thaliana LTPs constitutes a multigenic family with genes located on various chromosomes.

Allergens↗
PubMed2002

[Prevention of an IgE response to bovine beta-lactoglobulin by gene immunization in mice].

The therapeutic routes for the treatment of allergy have as their objective to prevent or diminish the specific IgE responsible for the appearance of the allergic reaction. This allergic reaction survives in the genetically predisposed subject and results in a dis-equilibrium of the "Th1-Th2 balance" by increasing the Th2 response. This Th2 response induces the production of IgE against environmental antigens, which from that time on become allergens. In this context, use of gene immunisation seems to be very interesting. The immunisation consists of the injection of an expression vector of bacterial origin, containing the cDNA of a protein of interest. Different studies have shown that the injection of such a plasmid into mice initiates a specific immune response of Th1 (IgG2a) type, stopping all further response of the Th2 (IgG1 and IgE) type. This "non-allergic" response is due to the intrinsic properties of the bacterial ADN, notably the presence of sequences of immunostimulants, the adjuvant of the Th1 response. We have sought to show such a preventative effect in the case of a food protein, bovine beta-lactoglobulin (BLG), a major allergen of cow's milk. Firstly, we made a expression plasmid that contained the cDNA of BLG. Intramuscular administration of this plasmid to mice allowed expression of the BLG in the native form at the site of the injection. The primary response induced by this type of immunisation is characterised by a mixed IgG1/IgG2a response and an absence of anti-BLG IgE. In addition, pre-immunisation of the mice with a plasmid that contained the cDNA of BLG prevented all further sensitisation with the protein administered by the intra-peritoneal route in the presence of alum, an adjuvant of the Th2 response. It appeared further that the preventative effect is dependent on the latent time between gene and protein immunisation. Prevention of the anti-BLG IgE response seems to result in an active inhibition by the cytokines such as interferon-gamma and interleukin 10, rather than a reduction in the production of type Th2 cytokines. Use of efficacious non-pathogenic vectors, that may be administered by the digestive route, could envisage a specific protection in the case of severe food allergies.

Allergens↗
PubMed2001

Induction of mucosal immune response after intranasal or oral inoculation of mice with Lactococcus lactis producing bovine beta-lactoglobulin.

The bovine beta-lactoglobulin (BLG) is a major cow's milk allergen. Here, we evaluated the immune response against BLG induced in mice, using the organism Lactococcus lactis, which has GRAS ("generally regarded as safe") status, as a delivery vehicle. The cDNA of the blg gene, encoding BLG, was expressed and engineered for either intra- or extracellular expression in L. lactis. Using a constitutive promoter, the yield of intracellular recombinant BLG (rBLG) was about 20 ng per ml of culture. To increase the quantity of rBLG, the nisin-inducible expression system was used to produce rBLG in the cytoplasmic and extracellular locations. Although the majority of rBLG remained in the cytoplasm, the highest yield (2 microg per ml of culture) was obtained with a secreting strain that encodes a fusion between a lactococcal signal peptide and rBLG. Whatever the expression system, the rBLG is produced mostly in a soluble, intracellular, and denatured form. The BLG-producing strains were then administered either orally or intranasally to mice, and the immune response to BLG was examined. Specific anti-BLG immunoglobulin A (IgA) antibodies were detected 3 weeks after the immunization protocol in the feces of mice immunized with the secreting lactococcal strain. Specific anti-BLG IgA detected in mice immunized with lactococci was higher than that obtained in mice immunized with the same quantity of pure BLG. No specific anti-BLG IgE, IgA, IgG1, or IgG2a was detected in sera of mice. These recombinant lactococcal strains constitute good vehicles to induce a mucosal immune response to a model allergen and to better understand the mechanism of allergy induced by BLG.

Administration, Intranasal↗
PubMed2001

Genetic immunisation with bovine beta-lactoglobulin cDNA induces a preventive and persistent inhibition of specific anti-BLG IgE response in mice.

BACKGROUND: Various studies have shown that DNA immunisation with gene allergen induces a non-allergic response. METHODS: We applied this new type of vaccination to bovine beta-lactoglobulin (BLG), a major cow's milk allergen, using a plasmid that allows the production of a partially secreted protein. Specific antibodies and cytokines were quantified in different immunisation protocols. RESULTS: The primary response in mice immunised with BLG-encoding plasmid (pBLG) is of the Th1 type. Restricted recognition of a native form of BLG in pBLG mice contrasted with a broader range of recognition in BLG-in-alum-immunised mice, notwithstanding the fact that alum favours the presentation of a native form of the antigen. We also demonstrated an inhibitory effect of pDNA immunisation on the Th2 response induced by a subsequent immunisation using BLG adsorbed on alum. However, this preventive effect is highly dependent on the time of pre-administration of the pBLG, with an optimal effect when pDNA immunisation occurred at least 21 days before protein administration. This preventive effect resulted concomitantly in the inhibition of BLG-specific IgE, in the induction of specific IgG2a, and in the decrease of the specific IgG1/IgG2 ratio. It is accompanied by an increase in IFNgamma and IL-10 secretion. Moreover, the preventive effect was shown to be persistent even after a booster immunisation with alum-adsorbed BLG. The Th1 orientation of the response is very likely due to the presentation of the protein in the Th1 environment due to plasmid immunostimulatory sequences, as intramuscular injection of BLG itself leads to a weak Th2 response and had no preventive effect on a subsequent sensitisation. CONCLUSION: This study further demonstrates the potential use of DNA immunisation for prevention of IgE response, but the window of action seems to be very restricted if we are to inhibit an established Th2 response efficiently.

Allergens↗
PubMed2001

Structure and function of milk allergens.

Proteins (CMP) involved in milk allergy are numerous and heterogeneous, with very few structural or functional common features. This heterogeneity is complicated by their genetic polymorphism, resulting in several variants for each protein. These variants are characterized by point substitutions of amino acids or by deletions of peptide fragments of varying size or by post-translational modifications such as phosphorylation or glycosylation. All of these modifications may affect allergenicity. No common molecular structure can be associated with allergenicity, although some homologous regions such as casein phospho-peptides can explain an IgE cross-reactivity. Three-dimensional structure is an important feature in CMP allergenicity but denatured and linear epitopes are also involved. Epitopes are numerous and widely spread along the CMP molecule. They may be located in hydrophobic parts of the molecule where they are inaccessible for IgE antibodies in the native conformation of the protein but become bioavailable after digestive processes. Peptides as short as ca. 12-14 amino acid residues may account for a significant part of the allergenicity of the whole molecule, which justifies the need to be careful before proposing any CMP hydrolysate for highly allergenic children.

Allergens↗
PubMed2000

Evaluation of a high IgE-responder mouse model of allergy to bovine beta-lactoglobulin (BLG): development of sandwich immunoassays for total and allergen-specific IgE, IgG1 and IgG2a in BLG-sensitized mice.

An animal model of food allergy represents an important tool for studying the mechanisms of induction and repression of an allergic reaction, as well as for the development of an immunotherapy to prevent or minimize such an adverse reaction. IgE and IgG1 (Th2 response) vs. IgG2a (Th1 response) are good markers for the induction of an allergic response in mice. Nevertheless, while the total serum concentrations of these isotypes are easy to measure using classical sandwich immunoassays, this is not the case for allergen-specific isotypes. To develop an animal model of allergy to bovine beta-lactoglobulin (BLG), we set up quantitative assays for total and for allergen-specific IgE, IgG1 and IgG2a. Microtiter plates coated either with anti-isotype antibodies (Abs) or with allergen were used for Ab capture, while anti-isotype Fab' fragments coupled to acetylcholinesterase were used for visualization. These assays of anti-BLG specific Abs are original in two ways. First, assay calibration is performed using anti-BLG specific mAbs, thus allowing good quantification of the different isotypes and subclasses of serum antibodies. Second, the detection of all anti-BLG specific Abs, i.e., those recognizing both the native and denatured forms of the protein, is achieved through indirect coating of BLG using biotin-streptavidin binding. The present assays are quantitative, specific to the isotype (cross-reactivity <0.5%), very sensitive (detection limit in the 10 pg/ml range), and reproducible (coefficient of variation less than 10%). Applied to the humoral response in mice sensitized with BLG adsorbed on alum, these assays proved to be a very useful tool for monitoring high IgE-responder mice following BLG immunization, and for an immunotherapy directed at polarizing the immune response.

Adsorption↗
PubMed2000

Post-translational phosphorylation affects the IgE binding capacity of caseins.

IgE response specific to those molecular regions of casein that contain a major phosphorylation site was analyzed using native and modified caseins and derived peptides. This study included (i) the naturally occurring common variants A1 and A from beta- and alphas2-caseins, respectively, which were purified in the native form and then dephosphorylated, (ii) a purified rare variant D of alphas2-casein which lacks one major phosphorylation site, and (iii) the native and dephosphorylated tryptic fragment f(1-25) from beta-casein. Direct and indirect ELISA using sera from patients allergic to milk showed that the IgE response to caseins is affected by modifying or eliminating the major phosphorylation site.

Binding Sites↗
PubMed1999

Assessment of allergic potential of (novel) foods.

In safety assessment of Novel Foods such as functional foods, allergy is a special issue on which particular emphasis has been placed. The reason for such concern is that incidence of food allergies is constantly and rapidly increasing. The severity of the reported incidents and the number of foods incriminated are also on the rise. The outstanding challenge is to understand what makes a common innocuous protein or peptide behave as an allergen for some groups of people, or why it may suddenly or progressively become a much more potent allergen than usual. It is therefore necessary to consider the risks of creating or unmasking new immunoreactive structures, or of overexposure to already reactive substances, as a result of new food-production and processing technologies. No test such as the use of animal models, the analysis of structure, function and physico-chemical properties is as yet available to evaluate or predict the allergenicity of a "novel" protein in a wholly reliable and objective manner. No indication has yet suggested that novel foods, and particularly recombinant proteins or genetically modified foods, would be more (or less) allergenic than the corresponding conventional foods. No particular structure can be described as being solely and intrinsically allergenic. The predictive approaches to determining the allergenic potential of NFs should therefore be subject to case-by-case critical appraisal allied to mandatory implementation of monitoring of the potential postmarketing impact of these new foodstuffs on public health.

Allergens↗