Thaumatin-like protein and baker's respiratory allergy
Received 9 July 2009; received in revised form 12 October 2009; accepted 19 October 2009.
Background
Baker's asthma and rhinitis are among the most common occupational diseases. Inhaled cereal flours, such as wheat, especially cause this disease.
Objective
To identify and test in vivo clinically important wheat allergens in baker's respiratory allergy in a Finnish population.
Methods
Potential wheat allergens were purified using chromatographic methods from salt-soluble protein extracts of wheat flour and were used in skin prick tests with serial 10-fold dilutions (0.5–0.005 mg/mL). Twenty 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 control group consisted of 10 healthy individuals. Molecular identities of purified wheat allergens were characterized using sodium dodecyl sulfate–polyacrylamide gel electrophoresis and tandem mass spectrometry.
Results
Allergen concentrations of 0.3–0.5 mg/mL revealed that 12 patients reacted to α-amylase inhibitor (α-AI), 9 to peroxidase I (PI), 9 to thaumatin-like protein (TLP), and 6 to lipid transfer protein 2G (LTP2G). Conversely, with allergen concentrations of 0.05 mg/mL, 5 patients responded to α-AI, 3 to PI, 4 to LTP2G, and 6 to TLP. Of these, TLP and LTP2G are now observed to be new allergens associated with baker's asthma.
Conclusions
In addition to the earlier-described α-AI and PI, TLP and LTP2G are important in vivo wheat allergens in baker's allergies in Finland. Further studies are needed to elucidate the role of these novel wheat allergens in respiratory disorders.
⁎Unit of Excellence for Immunotoxicology, Finnish Institute of Occupational Health, Helsinki, Finland
†Control of Hypersensitivity Diseases, Finnish Institute of Occupational Health, Helsinki, Finland
Requests for reprints should be addressed to: Maili Lehto, PhD, Unit of Excellence for Immunotoxicology, Finnish Institute of Occupational Health, Topeliuksenkatu 41 aA, FIN-00250 Helsinki, Finland
Disclosures: Authors have nothing to disclose.
Funding Sources: This study was supported by a grant from the Finnish Work Environment Fund (project No. 104083).
ABSTRACT