Lupine allergy: not simply cross-reactivity with peanut or soy.
BACKGROUND
Reports of lupine allergy are increasing as its use in food products increases. Lupine allergy might be the consequence of cross-reactivity after sensitization to peanut or other legumes or de novo sensitization. Lupine allergens have not been completely characterized.


OBJECTIVE
We sought to identify allergens associated with lupine allergy, evaluate potential cross-reactivity with peanut, and determine eliciting doses (EDs) for lupine allergy by using double-blind, placebo-controlled food challenges.


METHODS
Six patients with a history of allergic reactions to lupine flour were evaluated by using skin prick tests, CAP tests, and double-blind, placebo-controlled food challenges. Three of these patients were also allergic to peanut. Lupine allergens were characterized by means of IgE immunoblotting and peptide sequencing.


RESULTS
In all 6 patients the ED for lupine flour was 3 mg or less for subjective symptoms and 300 mg or more for objective symptoms. The low ED and moderate-to-severe historical symptoms indicate significant allergenicity of lupine flour. Two patients allergic to lupine but not to peanut displayed IgE binding predominantly to approximately 66-kd proteins and weak binding to 14- and 24-kd proteins, whereas patients with peanut allergy and lupine allergy showed weak binding to lupine proteins of about 14 to 21 or 66 kd. Inhibition of binding was primarily species specific.


CONCLUSIONS
Lupine allergy can occur either separately or together with peanut allergy, as demonstrated by 3 patients who are cosensitized to peanut and lupine.


CONCLUSIONS
Lupine flour is allergenic and potentially cross-reactive with peanut allergen, thus posing some risk if used as a replacement for soy flour.
Peeters
Kim A B M
KA
Department of Dermatology/Allergology, University Medical Center Utrecht, Utrecht, The Netherlands.
Nordlee
Julie A
JA
Penninks
André H
AH
Chen
Lingyun
L
Goodman
Richard E
RE
Bruijnzeel-Koomen
Carla A F M
CA
Hefle
Sue L
SL
Taylor
Steve L
SL
Knulst
André C
AC
D000328:Adult; D010367:Arachis / Q000276:immunology*; D003429:Cross Reactions; D005260:Female; D005512:Food Hypersensitivity / Q000209:etiology* / Q000276:immunology*; D006801:Humans; D015151:Immunoblotting; D031297:Lupinus / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D010936:Plant Extracts / Q000276:immunology; D012882:Skin Tests; D013025:Glycine max / Q000276:immunology*
D010936:Plant Extracts