Effects of combined high pressure and thermal treatment on the allergenic potential of peanut in a mouse model of allergy

• Ara h 2 is the major allergen in peanut.
• We analyzed the allergenicity of Ara h 2 in peanut (PN) after pressure and heat treatment.
• Reduced IgE-binding with PN was observed following pressure and heat treatment.
• Decreased PN-specific IgE titers were observed in mice fed treated PN.
• The allergenicity of PN was abolished following pressure and heat treatment.

Allergic reactions to peanut proteins are a worldwide concern. Ara h 2 in peanut (PN) is one of the most important peanut allergens (Koppelman, Wensing, Ertmann, Knulst, & Knol, 2004), which is recognized by serum immunoglobulin E (IgE) from more than 90% of peanut-allergic individuals studied by Stanley et al., 1997. Therefore, this study aimed at determining whether high pressure and thermal treatment could reduce the allergic properties of PN. Peanut protein extracts were treated with high pressure in 100–600 MPa and/or thermal treatment in 25–75 °C for 2.5–30 min, and the immunoreactivity of PN were analyzed by competitive inhibition enzyme-linked immunosorbent assays using pool sera from eight patients with peanut specific IgE. Compared to the boiling treatment, a significant reduction in IgE binding was observed when the samples were treated at 55 °C, 600 MPa for more than 10 min. Furthermore, in a BALB/c mouse model of allergy, significant reductions in specific IgE titers were observed in PN treated with high pressure and thermal (PNH) fed mice, accompanied by reduced histamine levels in serum. Similarly, real-time reverse transcription polymerase chain reaction revealed the decrease in mRNAs encoding interferon-γ, interleukin (IL)-4 and IL-10 in ileum tissues. PNH had almost no allergenicity in the BALB/c mouse model of PN allergy.Industrial relevanceHigh hydrostatic pressure (HHP) processing can inactivate microorganisms and enzymes, leaving sensory and nutritional quality almost unchanged. Furthermore, HHP could alter allergen conformation and hence decrease allergenic activity in rice, fish, milk and celery that were reported. As a health concern, peanut allergies have been studied in this work. We determined whether high pressure and thermal could reduce the allergic properties of peanut allergen Ara h 2. In addition, effects of high pressure and thermal treatment on the peanut allergenicity of Ara h 2 (PNH) were characterized using a BALB/c mouse model of allergy.