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目的：构建粉尘螨1类变应原（Der f 1）的T和B细胞表位嵌合基因原核表达载体。方法将Der f 1包含的5个T细胞表位（T1～T5）和6个B细胞表位（B1～B6），以B1-T1-B2-T2-B3-T3-B4-T4-B5-T5-B6和B1-B2-B3-B4-B5-B6-T1-T2-T3-T4-T5连接方式直接合成表位嵌合基因，并分别命名为Der f 1A和Der f 1B。构建原核表达重组质粒pET-28a（+）-Der f 1A和pET-28a（+）-Der f 1B，双酶切及测序验证的阳性克隆转化到E.coli BL21（DE3）后诱导表达。SDS-PAGE分析表达产物后进行纯化，并进行Western blotting鉴定。ELISA法检测嵌合蛋白对粉尘螨过敏患者血清IgE抗体的结合力。结果双酶切及测序结果表明，成功构建了原核表达重组质粒pET-28a（+）-Der f 1A和pET-28a（+）-Der f 1B；SDS-PAGE分析表明，Der f 1A和Der f 1B诱导并纯化成功，Western blotting结果进一步证实纯化了Der f 1A和Der f 1B嵌合蛋白。与Der f 1相比，Der f 1A和Der f 1B嵌合蛋白与粉尘螨过敏患者血清IgE抗体的结合能力显著降低（P均＜0.05），但Der f 1A和Der f 1B间差异无统计学意义（P＞0.05）。结论成功表达了Der f 1的T和B细胞表位嵌合蛋白，为粉尘螨过敏的特异性免疫治疗奠定了基础。“,”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.