The major allergen of sesame seeds (Sesamum indicum) is a 2S albumin.
BACKGROUND
Allergic reactions induced by ingestion of foods containing sesame seeds are a well recognized cause of severe food-induced anaphylaxis.


OBJECTIVE
This study aimed to identify and characterize the clinically most important major allergen of sesame seeds.


METHODS
Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and IgE immunoblotting were performed on sera of 10 patients selected for severe and documented allergic reaction after eating food containing sesame. The major allergen was purified by gel filtration and characterized by isoelectric point (pI), glycosylation and amino acid sequencing.


RESULTS
All the patients had positive IgE antibodies and skin prick tests (SPTs) to sesame. The major, clinically most important allergen was a protein with molecular mass of about 9000. It was not glycosylated, the amino acid sequence showed it was a 2S albumin with a pI of 7.3; the small and the large subunits, forming the whole protein, showed pI values of 6.5 and 6.0.
Pastorello
E A
EA
3rd Division of General Medicine, Ospedale Maggiore IRCCS, Milan, Italy. elidepa@box1.tin.it
Varin
E
E
Farioli
L
L
Pravettoni
V
V
Ortolani
C
C
Trambaioli
C
C
Fortunato
D
D
Giuffrida
M G
MG
Rivolta
F
F
Robino
A
A
Calamari
A M
AM
Lacava
L
L
Conti
A
A
D055516:2S Albumins, Plant; D000328:Adult; D000418:Albumins / Q000032:analysis*; D000485:Allergens / Q000032:analysis*; D052179:Antigens, Plant / Q000032:analysis*; D015153:Blotting, Western; D002648:Child; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000032:analysis / Q000276:immunology; D007526:Isoelectric Point; D019684:Magnoliopsida / Q000196:embryology*; D008297:Male; D008970:Molecular Weight; D012639:Seeds / Q000276:immunology*; D012882:Skin Tests
D055516:2S Albumins, Plant; D000418:Albumins; D000485:Allergens; D052179:Antigens, Plant; C540354:Ses i 1 allergen, Sesamum indicum; D007073:Immunoglobulin E