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目的：通过优化设计利用大肠杆菌表达人白细胞介素４（ＩＬ４） 并提高其表达量。方法：根据原核翻译起始序列的局部二级结构自由能，设计了ＡＵＧ 上下游序列，并在人ＩＬ４ 基因下游插入部分大肠杆菌ＬａｃＺ 序列以提高ｍＲＮＡ 的稳定性。结果：成功地构建了人ＩＬ４ 的高效表达克隆，命名为ｐＬＣＭ１８２ｈＩＬ４ 。ＳＤＳＰＡＧＥ 分析显示所表达的重组ＩＬ４ 蛋白质占细菌总蛋白的３０ ％ 。目的基因下游没有插入ＬａｃＺ序列所构建的表达克隆ｐＣＺＨｈＩＬ４ 在大肠杆菌中的表达量则占细菌总蛋白的２０ ％ 左右。结论：所设计的优化表达方法对人ＩＬ４ 基因的表达是成功的，在细胞因子的工程化表达中，优化设计对基因的表达量至关重要。
Objective: To optimize the design and use of E. coli expression of human interleukin 4 (IL 4) and increase its expression. Methods: According to the free energy of the local secondary structure of prokaryotic translation initiation sequence, AUG upstream and downstream sequences were designed, and part of E. coli LacZ sequence was inserted downstream of human IL4 gene to improve mRNA stability. Results: The human IL 4 high-expression clone was successfully constructed and named as pLCM182-hIL4. SDS-PAGE analysis showed that the expression of recombinant IL 4 protein accounted for 30% of total bacterial protein. The expression of pCZH-hIL4 expressed in E. coli without the LacZ sequence inserted downstream of the target gene accounted for about 20% of the total bacterial proteins. Conclusion: The optimized expression of human IL4 gene was successfully designed. In the engineering of cytokines, the optimized design is crucial to the gene expression.