Wu Z, O'Reilly M S, Folkman J, Shing Y
Department of Surgery, Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA.
Biochem Biophys Res Commun. 1997 Jul 30;236(3):651-4. doi: 10.1006/bbrc.1997.7032.
Angiostatin, a 38 kDa internal fragment of plasminogen, is an antiangiogenic endothelial cell inhibitor. It regresses several primary and metastatic tumors in mice. To produce recombinant angiostatin for further structural and functional studies, the mouse angiostatin gene preceded by a sequence including a signal peptide of plasminogen was introduced into baculovirus. Recombinant murine angiostatin was purified from the culture medium of angiostatin baculovirus-infected insect cells (yield = 1 mg/liter) with a single-step of lysine-Sepharose chromatography. The angiostatin baculovirus-infected insect cells expressed and secreted a 52 kDa polypeptide that demonstrated all of the biological activities of angiostatin. A partial amino acid sequence of the NH2-terminus of the secreted protein revealed that the signal peptide was recognized and properly cleaved in insect cells. The recombinant murine angiostatin potently inhibited the proliferation of bovine capillary endothelial cells in vitro (half maximal inhibition = 50 ng/ml) and suppressed the growth of primary Lewis lung carcinoma in vivo (6 mg/kg/day, T/C = 0.08).
血管抑素是纤溶酶原的一种38 kDa内部片段，是一种抗血管生成的内皮细胞抑制剂。它能使小鼠体内的几种原发性和转移性肿瘤消退。为了生产重组血管抑素以进行进一步的结构和功能研究，将带有纤溶酶原信号肽序列的小鼠血管抑素基因导入杆状病毒。通过赖氨酸-琼脂糖一步层析法从感染血管抑素杆状病毒的昆虫细胞培养基中纯化重组小鼠血管抑素（产量 = 1毫克/升）。感染血管抑素杆状病毒的昆虫细胞表达并分泌一种52 kDa的多肽，该多肽具有血管抑素的所有生物学活性。分泌蛋白NH2末端的部分氨基酸序列显示，信号肽在昆虫细胞中被识别并正确切割。重组小鼠血管抑素在体外能有效抑制牛毛细血管内皮细胞的增殖（半数最大抑制浓度 = 50纳克/毫升），在体内能抑制原发性Lewis肺癌的生长（6毫克/千克/天，T/C = 0.08）。
