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目的：百日咳毒素既是百日咳杆菌的主要毒性因子，又是重要的保护性抗原，其Ｓ１亚单位具有ＡＤＰ核糖转移酶活性和免疫保护性决定簇。为高效表达前构建的一个丧失酶活性但仍保持保护决定簇的Ｓ１变异子，开展了本研究。方法：通过添加人流感病毒血凝素基因信号序列或嵌膜序列的方法，对天然和变异Ｓ１亚单位基因片段作了遗传学修饰。然后使用重组杆状病毒技术使这些Ｓ１亚单位在昆虫细胞和昆虫幼虫中实现了高水平表达。结果：这些重组Ｓ１的表达水平介于每万个昆虫卵细胞０１８～１９３μｇ或每只昆虫幼虫０４６～４９８ｍｇ之间。天然信号肽和ＨＡ信号肽均可完整表达，但后者的切割效率（６１％～８１％）比前者（１６％～１９％）更高。所有带信号肽的Ｓ１亚单位均呈异质性表达（双带）。结论：重组Ｓ１亚单位的表达是高效和正确的，表达的异质性是由于信号肽切割不完全的缘故。
Objective: Pertussis toxin is not only the main virulence factor of Bordetella pertussis but also an important protective antigen. The S1 subunit has ADP-ribose transferase activity and immunoprotective determinants. In order to efficiently express a pre-constructed S1 mutant that lacks enzymatic activity but still retains the protective determinant, this study was conducted. Methods: The natural and mutant S1 subunit gene fragments were genetically modified by adding human influenza virus hemagglutinin gene signal sequence or inlaid sequence. These S1 subunits were then used to achieve high levels of expression in insect cells and insect larvae using recombinant baculovirus technology. Results: The expression levels of these recombinant S1s ranged from 018 ~ 193μg per 10,000 insect eggs or 046 ~ 498mg per insect larva. Both the native signal peptide and the HA signal peptide were expressed intact, but the latter had higher cleavage efficiency (61% -81%) than the former (16% -19%). All S1 subunits with signal peptide were heterogeneous (double band). Conclusion: The expression of recombinant S1 subunit is efficient and correct. The heterogeneity of expression is due to incomplete cleavage of signal peptide.