rHev b 6.02 Latex

Code: k220
Latin name: Hevea brasiliensis
Common names: Hevein
Recombinant allergen
Hevea brasiliensis allergen Hev b 6.02.
5 kDa
Allergen description
Hev b 6.02 (1-3), hevein, is a small protein, which has been identified as the most common allergen for healthcare workers (HCW) allergic to Latex. About 75% of these workers allergic to Latex had hevein-specific antibodies (4). Hevein is not only a major IgE-binding allergen in Natural rubber latex (NRL) but also in other Latex manufactured products (5-6). Prohevein, Hev b 6.01, is cleaved naturally to yield 2 allergenic fragments, the N-terminal hevein, Heb b 6.02, and the C-terminal portion, Hev b 6.03 (5, 7). All 3 allergens exist in the plant, although the ratio between Hev b 6.01 and Hev b 6.03 is about 30:1 (8). All 3 components act as independent allergens (1).

In a study, serum-specific IgE to hevein was detected by ELISA in 48 of 64 (75%) sera from HCW allergic to Latex, and in 3 of 11 (27%) sera from patients with spina bifida (SB) and hypersensitivity reactions to Latex. Skin-positive tests hevein was found in 17 of 21 (81%) patients with Latex allergy (9).

Hevein (Hev b 6.02) is the main allergen cross-reacting with Avocado in subjects with Latex allergy. Results of immunoblots and immunoblot inhibition with 11 serum samples confirmed that a 30-kDa protein in Avocado was the major IgE-binding component; the IgE-binding reactivity to this protein could be inhibited by hevein in all sera tested. Sixty-seven of 91 (73%) subjects from the HCW group and all 19 subjects in the SB group with positive IgE antibodies to hevein also had elevated IgE values to Avocado (4).

As in all diagnostic testing, the diagnosis is made by the physican based on both test results and the patient history.