EPITOPE-BASED VACCINE FOR THE TREATMENT OF DER F 3 ALLERGY.

Zhan, Xiaodong; Li, Chaopin; Jiang, Yuxing; Li, Na

INTRODUCTION mites allergic asthma is caused by exposure to home dust mite (HDM). Der f 3 is believed to be one of the major allergens in mites allergic asthma. The work was to identify the immune characteristics of Der f 3 epitope-based vaccine containing T cell and B cell epitopes. METHODS T cell lines were generated from peripheral blood mononuclear cells of Der f 3 allergic patients. Three T cell epitopes and five B cell epitopes of Der f 3, which we identified previously, were selected to design a polypeptide (named Der f3-peptides). DNA constructions encoding these Der f 3-peptides were expressed in Escherichia coli. The T cell lines were stimulated with the peptides and tested for proliferative capacity and cytokine production. RESULTS plasmid pET28a (+)-Der f 3-peptides was constructed and expressed in E. coli BL21, and the Der f3-peptides protein was purified and confirmed by Western blotting. The Der f 3-peptides were recognized by the T cell clones from allergic patients. SI value of Der f 3 group and Der f 3-peptides group were both higher than that of PBS group (P<0.05). The Der f 3 and Der f 3 peptides induced secretions of IL-4 and IL-5 were decreased compared with that of PBS group (P<0.05). The capacity of IgE-binding to Der f 3-peptides (41.25±5.67) μg/ml was decreased dramatically compared with that of Der f 3 (83.60 ± 10.92) μg/ml (P < 0.05). CONCLUSIONS our results demonstrate that several major T cell epitopes and B cell epitopes of Der f 3 can be valuable for designing the peptide-based immunotherapeutics for the mites allergic asthma.