Bee moth (Galleria mellonella) allergic reactions are caused by several thermolabile antigens.
BACKGROUND
Exposure and contact with bee moth (Galleria mellonella) larvae (Gm) can cause an allergic reaction both in anglers and breeders. We described the case of an amateur fisherman who experienced an allergic reaction using Gm but not using heat-treated Gm (h-Gm) (mummies). The aim of this study was to demonstrate by immunoblotting and radioallergosorbent test (RAST)-inhibition experiments the loss of allergenic epitopes in h-Gm extracts.


METHODS
Galleria mellonella larvae and h-Gm were homogenized and extracted at 10% (w/v) in 0.5 M phosphate-buffered saline, pH 7.4 containing 0.5% NaN(3) for 16 h at 4 degrees C. Gm and h-Gm extracts were electrophoresed in a 10% polyacrylamide precast Nupage Bis-Tris gel at 180 mA for 1 h and the resolved proteins stained with 0.1% Coomassie brilliant blue and the molecular weight calculated. For the immunoblotting detection of allergenic components the resolved extracts were transferred onto a nitrocellulose membrane and incubated with the patient's serum. Bound specific-IgE was detected by peroxidase-conjugated anti-human IgE. RAST inhibition experiments were performed according to the Ceska method.


RESULTS
The protein profile of Gm and h-Gm extracts resulted markedly different in number, intensity and the position of bands, indicating that heat-treatment modifies the chemical-physical characteristics of the protein contents. The Gm extract showed a strong-coloured band at 73 kDa and more than 20 components ranging from 12 to 133 kDa; h-Gm showed two main band at 77 and 38 kDa and about 15 faint bands between 20 and 133 kDa apparently without any correspondence to the bands present in the Gm extract. Immunoblotting with the patient's serum demonstrated several bands of reactivity with the Gm extract ranging from 20 to 100 kDa and no recognizable bands, but only a diffuse smear with h-Gm. When used in a RAST inhibition experiment the h-Gm extract demonstrated an inability to compete with the Gm one for the binding to patient's IgE serum.


CONCLUSIONS
The h-Gm seems to lose the allergenic epitopes and has two advantages for anglers: to avoid new possible sensitizations as well as allergic symptoms in sensitized people, without interfering with their skills and satisfaction in their fishing performance.
Villalta
D
D
Immunologia Clinica e Virologia, Dipartimento di Medicina di Laboratorio, Azienda Ospedaliera Santa Maria degli Angeli, Pordenone, Italy.
Martelli
P
P
Mistrello
G
G
Roncarolo
D
D
Zanoni
D
D
D000328:Adult; D000818:Animals; D000941:Antigens / Q000276:immunology*; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes; D006358:Hot Temperature; D006801:Humans; D006967:Hypersensitivity / Q000209:etiology*; D015151:Immunoblotting; D007814:Larva / Q000276:immunology; D008297:Male; D008970:Molecular Weight; D009036:Moths / Q000276:immunology*; D011852:Radioallergosorbent Test
D000941:Antigens; D000939:Epitopes