Experimental immunology Proteomic and immunological identification of two new allergens from silkworm (Bombyx mori L.) pupae

This study explored food allergy caused by eating silkworm (Bombyx mori L.) pupae, a traditionally accepted food and animal feed in East and Southeast Asia, and identified two new allergens by proteomic and immunological methods. Proteins isolated from silkworm pupae were separated by two-dimensional gel electrophoresis (2-DE); pooled sera from patients allergic to silkworm pupa proteins were used to detect immunoglobulin E (IgE)-binding proteins by western blotting, and allergens specific for silkworm pupa consumption-caused allergy were visualised with the ECL reagents. The selected allergen proteins were further identified by matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) analysis. Finally, chitinase and paramyosin were identified as silkworm pupa proteins showing strong immunoglobulin (IgE)-binding reaction. Analysis of the sequence homology of the two proteins using the AllergenOnline database indicated that chitinase and paramyosin shared 24.8% and 62.8% sequence homology with known allergens Der f 18 (Dermatophagoides farinae) and Der p 11 (Dermatophagoides pteronyssinus), respectively. Our results shed light on the understanding and treatment of silkworm pupa allergy.