Prevalence of food allergy Prevalence of food allergy 0,8% 0,8% - PowerPoint PPT Presentation

� Prevalence of food allergy Prevalence of food allergy � � 0,8% 0,8% - - 6% 6% of adults of adults � � 3,52% 3,52% of of french population ( french population (Kanny Kanny et al. et al., 2001) , 2001) � � Higher Higher prevalence prevalence in in children children � � Symptoms of food allergy Symptoms of food allergy � ) ) troubles respiratoires 6% problèmes 70% cutanés troubles 24% gastro- intestinaux

� most frequent allergens most frequent allergens � � nutritional environment nutritional environment � � age age � Adults children Adults children fish eggs fish eggs eggs peanut eggs peanut cow milk fish cow milk fish soya soya cow milk cow milk

� Fish Allergens Fish Allergens � Cartography Cartography � Hemmens Hemmens et et al al ., 1989 ., 1989 : 6 : 6 IgE IgE- -reactive bands reactive bands (12 (12 - - 92 92 kDa kDa) ) � � Bernhisel Bernhisel- -Broadbent Broadbent et al et al ., 1992 ., 1992 : 7 : 7 IgE IgE- -reactive bands reactive bands (12 (12 - - 78 78 kDa kDa) ) � � Hansen Hansen et al et al ., 1997 ., 1997 : 8 : 8 IgE IgE- -reactive bands reactive bands (12 (12 - - 101 101 kDa kDa) ) � � Dory Dory et al et al ., 1998 ., 1998 : 15 : 15 IgE IgE- -reactive bands reactive bands (12 (12 - - 130 130 kDa kDa) ) � Hypothesis : : oligomerisation oligomerisation Hypothesis - multiples multiples of of 12 12 kDa kDa - - detection of oligomers of oligomers in in presence of presence of EDTA EDTA - detection

� Fish allergens Fish allergens - - 2 2 � � Aas Aas et al. et al. , 1966 et , 1966 et Elsayed Elsayed et al et al ., 1971 ., 1971 : Isolation : Isolation and and � characterization of of Gad cI Gad cI from from Gadus callarias Gadus callarias characterization � Lindström Lindström et et al al ., 1996 ., 1996 : Identification : Identification of of 2 2 isoforms isoforms of of � parvalbumin parvalbumin in in salmon salmon � Bugajska Bugajska- -Schretter Schretter et al et al ., 2000 ., 2000 : Purification : Purification and and � characterization of the major major allergen of the carp allergen of the carp characterization of the

� Gad cI Gad cI ( ( Gadus callarias Gadus callarias ) ) : : � sarcoplasmic β β− − parvalbumin – sarcoplasmic parvalbumin – <=> 12.3 acids <=> – 113 113 amino amino acids 12.3 kDa kDa, pI = 4.75 , pI = 4.75 – =>sequential epitope sequential epitope – allergenicity allergenicity => – Calcium binding site Calcium binding binding site site Calcium loop loop loop loop loop loop AB AB CD CD EF EF 1 13 33 49 64 80 103 1 13 33 4 9 64 80 103 113 113 Aas et al ., 1966 & Elsayed et al ., 1971

� P41 P41 � P24 P24 � � � Varies in Varies in function function of of � A A dimer dimer of of an an isoform isoform � � storage conditions conditions of Gad cI in Gad cI in Gadus Gadus storage of morhua morhua

PERSPECTIVES 1/ Allergenicity 1/ Allergenicity � skin skin testing and mediator testing and mediator release release � � Detection Detection of allergenic epitopes of allergenic epitopes � � cross cross- -reactivity between species reactivity between species � 2/ food quality 2/ food quality � Detection Detection of of major major allergens allergens in in fish products fish products � � storage storage conditions conditions � � identification identification of species of species � 3/ Immunotherapy 3/ Immunotherapy � DNA Vaccination DNA Vaccination �