Construction and expression of a chimeric gene with T-/B-cell epitopes of major allergen group 1 from Dermatophagoides farina / 中国血吸虫病防治杂志

ABSTRACT

Objective To construct and express a chimeric gene with T-/B-cell epitopes of the major allergen group 1 from Dermatophagoides farina(Der f 1). Methods Two chimeric genes,Der f 1A and Der f 1B,were synthesized as B1-T1-B2-T2-B3-T3-B4-T4-B5-T5-B6 and B1-B2-B3-B4-B5-B6-T1-T2-T3-T4-T5 pattens. Two recombinant vectors,pET-28a(+)-Der f 1A and pET-28a(+)-Der f 1B,were constructed for prokaryotic expression. These chimeric genes were induced by 1 mmol/L IPTG (final concentration),digested with restriction enzymes and sequenced. The chimeric proteins were analyzed by SDS-PAGE and Western blotting. Results After digestion by restriction enzymes and sequencing,the recombinant vectors were constructed successfully. The specific bands for chimeric proteins were visible by SDS-PAGE and Western blotting,suggesting that these proteins were purified successfully. Further analyses were performed for IgE-binding properties of Der f 1A and Der f 1B to sera from patients sensitized to house dust mite. Compared with the parental allergens Der f 1,Der f 1A and Der f 1B had reduced IgE-binding capacity(both P0.05). Conclusion Two chimeric proteins are expressed successfully,which contain T-/B-cell epitopes of Der f 1 and provide a basis for specific immunotherapy.