Meat allergy and the allergenic components: Underlining reasons for the absence of clinical presentation to meat antigens despite the presence of high levels of specific IgE

Abstract

Little is known about meat allergy and the allergenic components involved. Using a dot-blot immunoarray, we showed high IgE-binding frequency to beef (8%), pork (12%) and mutton (5%) in 1096 allergic patientsa?? sera tested. High degree of cross-reactivity between the meat antigens was observed with inhibition ELISA. Identification and characterization of meat-based allergens were achieved using a dual bioinformatics (allergenicity prediction based on allergen-motif or sequence homology) and proteomics (2D electrophoresis and mass spectrometry) approach. Bioinformatics approach predicted 252 distinct putative allergens from six animal species whereas proteomics approach identified 56 IgE-reactive proteins from beef, pork and mutton. Despite presence of high levels of meat specific IgEs, only 2 out of 18 patients tested via SPT were beef-positive. The high IgE-binding to meat extracts is mainly due to presence of mammalian cross-reactive carbohydrate determinants (CCDs). Negative SPT is due to presence of a??blockinga?? IgG antibodies which inhibits histamine release.