Thaumatin-like protein is new allergen associated with baker's asthma

Baker's asthma and rhinitis are among the most common occupational diseases. Inhaled cereal flours, such as wheat, especially cause this disease. Prevalence of wheat allergy in Japan is 0.2% - the assessment was based on questionnaire-based exam, skin prick test, and omega-5 gliadin sIgE (http://goo.gl/Mp4nW).

Potential wheat allergens were purified using chromatographic methods from protein extracts of wheat flour and were used in skin prick tests.

10 patients with baker's rhinitis, asthma, or both participated in this study. All the patients had positive skin prick test reactions and specific IgE antibodies to wheat flour. The series included 10 control patients.

Allergen concentrations of 0.3-0.5 mg/mL revealed that:

- 12 patients reacted to a-amylase inhibitor (alpha-AI)
- 9 to peroxidase I (PI)
- 9 to thaumatin-like protein (TLP)
- 6 to lipid transfer protein 2G (LTP2G)

Of these, TLP and LTP2G are now observed to be new allergens associated with baker's asthma.

In addition to the earlier-described alpha-AI and PI, TLP and LTP2G are important in vivo wheat allergens in baker's allergies.

Thaumatin is a low-calorie protein sweetener and flavor modifier. The thaumatins were first found as a mixture of proteins isolated from the katemfe fruit (Thaumatococcus daniellii Bennett) of west Africa.

References:
Thaumatin-like protein and baker's respiratory allergy. Lehto M, Airaksinen L, Puustinen A, Tillander S, Hannula S, Nyman T, Toskala E, Alenius H, Lauerma A. Ann Allergy Asthma Immunol. 2010 Feb;104(2):139-46.
Occupational sensitization to soy allergens in workers at a processing facility, high molecular weight allergens Gly m 5 and Gly m 6 may be the respiratory sensitizers http://goo.gl/6oXYd
Workforce occupational asthma in New Zealand. The highest risks: printer/baker/sawmill labourer/metal processing. Ann Occup Hyg. 2010.
Image source: Wheat flour, Wikipedia, R. Wampers, Creative Commons Attribution-Share Alike 2.0 Belgium license.

4 comments:

  1. What proteins are responsible for IgE sensitivity to wheat? Is thaumatin (PR-5) allergy common and is it a pan allergen? I would appreciate your perspective.

    ReplyDelete
  2. "What proteins are responsible for IgE sensitivity to wheat?"

    Answer:

    Triticum aestivum 19 (Tri a 19)

    http://allergycases.org/2010/08/wheat-allergy.html

    ReplyDelete
  3. Also don't forget to mention that these are primary triggers of celiac disease.

    ReplyDelete
  4. Anonymous12/30/2010

    Actually, celiac disease is not IgE-mediated allergy (in fact, it is not an allergy at all, using its narrow definition). Celiac diseases is mediated by cells, not immunoglobulins.

    ReplyDelete

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