The effect of thermal processing on the IgE reactivity of the non-specific lipid transfer protein from apple, Mal d 3
Article first published online: 27 JUL 2005
Volume 60, Issue 10, pages 1262–1268, October 2005
How to Cite
Sancho, A. I., Rigby, N. M., Zuidmeer, L., Asero, R., Mistrello, G., Amato, S., González-Mancebo, E., Fernández-Rivas, M., van Ree, R. and Mills, E. N. C. (2005), The effect of thermal processing on the IgE reactivity of the non-specific lipid transfer protein from apple, Mal d 3. Allergy, 60: 1262–1268. doi: 10.1111/j.1398-9995.2005.00876.x
- Issue published online: 31 AUG 2005
- Article first published online: 27 JUL 2005
- Accepted for publication 6 March 2005
- Apple allergen;
- food allergy;
- Mal d 3;
- thermal treatment
Background: Non-specific lipid transfer proteins (LTPs) are involved in allergy to fresh and processed fruits. We have investigated the effect of thermal treatment and glycation on the physico-chemical and IgE-binding properties of the LTP from apple (Mal d 3).
Methods: Mal d 3 was purified from apple peel and the effect of heating in the absence and presence of glucose investigated by CD spectroscopy, electrospray and MALDI-TOF mass spectrometry. IgE reactivity was determined by RAST and immunoblot inhibition, SPT and basophil histamine release test.
Results: The identity and IgE reactivity of purified Mal d 3 was confirmed. Mild heat treatment (90°C, 20 min) in the absence or presence of glucose did not alter its IgE reactivity. More severe heat treatment (100°C, 2 h) induced minor changes in protein structure, but a significant decrease in IgE-binding (30-fold) and biological activity (100- to 1000-fold). Addition of glucose resulted in up to four glucose residues attached to Mal d 3 and only a 2- and 10-fold decrease of IgE-binding and biological activity, respectively.
Conclusions: Only severe heat treatment caused a significant decrease in the allergenicity of Mal d 3 but glycation had a protective effect. The presence of sugars in fruits may contribute to the thermostability of the allergenic activity of LTP in heat-processed foods.