抗黏附多肽的聚乙二醇化研究

The pegylation of anti-adhesion polypeptide

目的观察聚乙二醇化抗黏附多肽酪-异亮-甘-丝-精（YIGSR）对人肝癌高转移细胞株MHCC97H体外基质黏附抑制能力和在大鼠血清体外的降解。方法将甲氧基聚乙二醇丙醛10000（mPEGALD10000）与YIGSR在PH4到6，摩尔比1：1到10：1条件下偶联成聚乙二醇化YIGSR（PEG—YIGSR）。比较两者的基质黏附抑制能力及在SD大鼠血清中的降解速率。结果修饰率可以达到99．9％以上，PEG-YIGSR的黏附抑制率达19．5％，且呈时间剂量依赖关系。PEG-YIGSR在大鼠血清中的降解速度明显慢于YIGSR，药时曲线下面积（AUC）分别为（1249±36）mg／min·L^-1和（1146±47）mg／min·L^-1。结论PEG—YIGSR保留了抗肿瘤细胞黏附的作用，且在体外血清中的降解速率减慢，有助于延长YIGSR发挥作用的时间。

Objective To investigate the modified methods of polyethylene glycol （PEG） to polypeptide YIGSR, and the degradation of PEG-YIGSR in serum of SD rats in vitro, and the adhesion inhibi- tory potential of PEG-YIGSR on the hepatoeellular carcinoma cell line MHCC97H cells. Methods YIGSR was reacted to the mPEGALD10000 synthesizing the pegylated YIGSR conjugate （PEG-YIGSR） under the certain conditions （pH 4 to 6 ,PEG： YIGSR 1：1 to 10：1 ）. The couple rate of pegylation and the degradation speed of PEG-YIGSR in SD rat serum were detected by using the LC-MS method in vitro. The hepatocellular carcinoma cell line MHCC97H cells were treated with PEG-YIGSR, and then the cell adhesion potential was tested by in vitro cell-matrix adhesion test. Results The couple rate of pegylation was up to 99.9% in different pH values,and it was increased with the ineresse of PEG modifier dose. PEG-YIGSR markedly inhibited cell adhesion to laminin （LN） up to 19.5% in a dose-and time-dependent manner. The degradation speed of PEG-YIGSR in SD rat serum was slower than that of YIGSR in vitro [ AUC was （1249 ＋36） mg/min · L^-1 versus （1146 ＋47） mg/min· L^-1]. Conclusion PEG-YIGSR still kept original inhibition potential on MHCC97H cells adhesion to LN. The action time of PEG-YIGSR would extend due to its slow degradation in SD rat serum.