Safety evaluation of a whey protein fraction containing a concentrated amount of naturally occurring TGF-β2

Safety evaluation of whey derived beta-lactoglobulin, Lacprodan® BLG

The safety of Lacprodan® BLG, a whey-based protein, was evaluated with respect to genotoxicity and sub-chronic toxicity according to regulatory requirements. Lacprodan® BLG did not show any mutagenic potential in a bacterial reverse mutation assay or any clastogenic or aneugenic potential in an in vitro micronucleus assay performed in human lymphocytes. In a sub-chronic toxicity study, groups of 10 male and 10 female Wistar rats received the test item orally by gavage for 90 days at dose levels of 100, 300 and 1000 mg/kg bw/day. A control group, also including 10 male and 10 female rats, received sterile water, as vehicle. No treatment-related clinical observations or toxicological effects on body or organ weights, food consumption, ophthalmic effects, hematology, clinical chemistry, fertility, urinalysis, or pathology were identified. Therefore, the no-observed-adverse-effect level (NOAEL) for Lacprodan® BLG in the 90-day toxicity study was established as 1000 mg/kg bw/day, corresponding to the highest dose level administered.

Oral Tolerance Induction to Newly Introduced Allergen is Favored by a Transforming Growth Factor-β-Enriched Formula

Food allergies have become a major healthcare concern, hence preventive efforts to ensure oral tolerance induction to newly introduced antigens are particularly relevant. Given that transforming growth factor-β (TGF-β) plays a key role in immune tolerance, we tested whether an infant formula enriched with TGF-β would improve oral tolerance induction. A partially hydrolyzed whey protein-based formula was enriched with cow's-milk-derived TGF-β (TGF-β-enriched formula) by adding a specific whey protein isolate (WPI). The manufacturing process was optimized to achieve a concentration of TGF-β within the range of human breast milk concentrations. Protection from allergic sensitization and immune response was assessed in a mouse model. Adult mice received the TGF-β-enriched formula, a control non-enriched formula, or water ad libitum for 13 days before sensitization and suboptimal tolerization to ovalbumin (OVA). When compared to non-tolerized mice, suboptimally-tolerized mice supplemented with the TGF-β-enriched formula showed significantly lower levels of total immunoglobulin-E (IgE) and OVA-specific (IgG1). Mouse mast-cell protease-1 (mMCP-1) and cytokine levels were also significantly decreased in suboptimally-tolerized mice fed the TGF-β-enriched formula. In conclusion, oral supplementation with cow's-milk-derived TGF-β decreased allergic responses to newly introduced allergens and thus reduced the risk of developing food allergy.

Safety of Whey basic protein isolates as a novel food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on whey basic protein isolate as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is obtained by ion exchange chromatography of skimmed cow's milk. The applicant intends to market the NF in infant and follow-on formulae and meal replacement beverages, dietary foods for special medical purposes and as food supplements. The highest estimated intake of the NF based on the proposed uses and use levels would be 24.8 mg/kg body weight (bw) per day in infants and 27.8 in toddlers. The information provided on composition, specifications, production process and stability of the NF do not raise safety concerns. Taking into account the composition of the NF and the intended use levels, the Panel considers that the consumption of the NF is not nutritionally disadvantageous. The Panel considers that there is no concern with respect to genotoxicity. The no observed adverse effect level (NOAEL) of a subchronic 13-week rat study was 2000 mg/kg bw per day. Considering the source, the production process and nature of the NF, the Panel considers the margin of exposure (MOE) of 154 to be sufficient for the adult population (on a high-estimated intake of 13 mg/kg bw). For infants and toddlers, the MOE would be at least 81 and 72, respectively. Taking into account the composition of the NF, its source, the history of consumption of the main components of the NF, the production process and that the NOAEL in a subchronic rat study was the highest dose tested the Panel considers that also the MOE for infants and toddlers are sufficient. The Panel concludes that the novel food ingredient, whey basic protein isolate, is safe under the proposed uses and use levels.

Long-term reduction in food allergy susceptibility in mice by combining breastfeeding-induced tolerance and TGF-β-enriched formula after weaning

BACKGROUND

Oral tolerance induction in early life is a promising approach for food allergy prevention. Its success requires the identification of factors necessary for its persistence.

OBJECTIVES

We aimed to assess in mice duration of allergy prevention by breastfeeding-induced oral tolerance and whether oral TGF-β supplementation after weaning would prolong it.

METHODS

We quantified ovalbumin (OVA) and OVA-specific immunoglobulin levels by ELISA in milk from the EDEN birth cohort. As OVA-specific Ig was found in all samples, we assessed whether OVA-immunized mice exposed to OVA during lactation could prevent allergic diarrhoea in their 6- and 13-week-old progeny. In some experiments, a TGF-β-enriched formula was given after weaning.

RESULTS

At 6 weeks, only 13% and 34% of mice breastfed by OVA-exposed mothers exhibited diarrhoea after six and seven OVA challenges vs. 44% and 72% in mice breastfed by naïve mothers (P = 0.02 and 0.01). Protection was associated with decreased levels of MMCP1 and OVA-specific IgE (P < 0.0001). At 13 weeks, although OVA-specific IgE remained low (P = 0.001), diarrhoea occurrence increased to 32% and 46% after six and seven OVA challenges in mice breastfed by OVA-exposed mothers. MMCP1 levels were not significantly inhibited. Supplementation with TGF-β after weaning induced a strong protection in 13-week-old mice breastfed by OVA-exposed mothers compared with mice breastfed by naive mothers (0%, 13% and 32% of diarrhoea at the fifth, sixth and seventh challenges vs. 17, 42 and 78%; P = 0.05, 0.0043 and 0.0017). MMCP1 levels decreased by half compared with control mice (P = 0.02). Prolonged protection was only observed in mice rendered tolerant by breastfeeding and was associated with an improved gut barrier.

CONCLUSIONS

In mice, prevention of food allergy by breastfeeding-induced tolerance is of limited duration. Nutritional intervention by TGF-β supplementation after weaning could prolong beneficial effects of breast milk on food allergy prevention.