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构建了人纤维结合素（ＦＮ）的三功能结构域重组多肽的两个表达质粒，分别编码两个重组多肽：ＣＨ６２（ＦＮ的Ｐｒｏ１２３９～Ｓｅｒ１５１５经Ｍｅｔ和Ａｌａ１６９０～Ｖａ１２０４９相连）和ＣＨ６３（从ＣＨ６２中删除了Ｉｌｅ１８５０～Ｇｌｕ１９７８）．ＣＨ６２在大肠杆菌中的表达效率很低，而ＣＨ６３的表达效率则很高，结果提示ＦＮ分子中的Ａｓｐ１９６１～Ｇｌｕ１９７８序列是影响三结构域多肽在大肠杆菌中表达的关键结构．ＣＨ６３经过溶解和复性后，可通过肝素－琼脂糖亲和层析得到纯品，所得纯品具有结合肝素和结合细胞的功能，且结合细胞的能力比双结构域ＦＮ多肽更强，表明两个结合细胞的功能结构域均有活性．ＣＨ６３的制备为进一步研究具有更强的抑制肿瘤转移作用的基因工程制品奠定了基础．
Two expression plasmids of three functional domain recombinant polypeptides of human fibronectin (FN) were constructed and encoded two recombinant polypeptides: CH62 (Pro1239 ~ Ser1515 of FN linked by Met and Ala1690 ~ Va12049) and CH63 Deleted Ile1850 ~ Glu1978). The low efficiency of CH62 expression in E. coli and the high efficiency of CH63 expression indicated that the Asp1961 ~ Glu1978 sequences in FN were the key structures affecting the expression of three-domain polypeptides in E. coli. CH63 after being lysed and refolded, can be purified by heparin-agarose affinity chromatography. The obtained pure product has the function of binding heparin and bound cells, and the ability to bind cells is stronger than that of double-domain FN polypeptide, indicating that two Each of the functional domains that bind to the cell is active. The preparation of CH63 lays the foundation for the further study of genetically engineered products with stronger inhibition of tumor metastasis.