Prevalence of IgE antibodies to extensively purified Hev b13 and Hev b2 in natural rubber latex (NRL) allergic patients

Abstract

Rationale Hevb13 and Hev b2 are suggested to be important NRL allergens recognized by more than 60% of the patients. We have noticed that when purifying these allergens the preparations even after several purification steps still bind monoclonal and polyclonal antihevein (Hev b6.02) antibodies. By extended purification we have obtained Hev b13 and Hev b2 preparations which do not bind antihevein antibodies. Methods Hev b13 and Hev b2 were isolated form the NRL “B-serum” and purified under non-denaturing conditions using an extended number of chromatographic steps. Mass spectrometry and quantitative immunoassays with monoclonal antibodies to major NRL allergens were used to assess the identity and purity of the preparations. Sera from NRL allergic patients (n=100), atopic controls, not allergic to NRL (n=75), and blood donors (n=100) were analyzed. IgE to Hev b5, and Hev b6.01 were also assessed and the cut-off level for positivity in all assays was set at 97th percentile of the atopic subjects. Results IgE to Hev b13 was detected in 18% of NRL allergic patients and Hev b2 in 17%, while binding to Hev b5 was seen in 27% and to Hev b6.01 in 54% of the patients. One blood donor had IgE to Heb b 6.01 and two donors to Hev b2. Conclusions The prevalence of IgE antibodies to extensively purified Hev b13 and Hev b2 was in Finnish NRL allergic patients considerably less than earlier reported elsewhere.