Hypersensitivity linked to exposure of Broad bean protein-s- in allergic patients and BALB and c mice

Authors
D. Kumar, S. Kumar, A. K. Verma, A. Sharma, A. Tripathi, et al.

Lab
CSIR-Indian Institute of Toxicology Research, Lucknow, India

Journal
NUTRITION

Abstract
Objective
Broad bean (Vicia faba L.), a common vegetable belongs to the family Fabaceae is consumed worldwide. Limited studies have been done on allergenicity of Broad bean that led us to undertake this work.
Methods
Simulated gastric fluid (SGF) assay and IgE immunoblotting were carried out to identify pepsin resistant and IgE binding proteins. Broad beans allergenicity was assessed in allergic patients, BALB/c mice, splenocytes and RBL-2H3 cells.
Results
Eight Broad bean proteins of approximate molecular weight 70, 60, 48, 32, 23, 19, 15 and 10 kDa that remained undigested in SGF, showed IgE binding capacity as well. Out of 127 allergic patients studied, Broad bean allergy was evident in 16 patients (12%). Mice sensitized with Broad bean showed increased levels of histamine, total and specific IgE, and severe signs of systemic anaphylaxis over the controls. Enhanced levels of histamine, prostaglandin D2, cysteinyl leukotriene and β-hexosaminidase release were observed in the primed RBL-2H3 cells following Broad bean exposure. The levels of IL-4, IL-5, IL-13 and RANTES were found enhanced in Broad bean treated splenocytes culture supernatant over control.
Conclusion
This study inferred that Broad bean proteins have ability to elicit allergic responses due to the presence of clinically relevant allergenic proteins.