西妥昔单抗注射液生物学活性分析

Analysis of Bioactivity of the New-Developed Cetuximab Injection

目的:对自行开发的爱必妥类似物西妥昔单抗进行体内及体外活性分析。方法:采用表皮生长因子受体(EGFR)结合实验、表面等离子共振法(SPR)、磷酸化抑制实验及细胞生长抑制实验分析西妥昔单抗的生物学活性,通过小鼠异体移植肿瘤的抑制实验分析体外生物学活性与药效关系。结果:体外亲和力分析结果表明,西妥昔单抗可特异结合人EGFR,亲和力与爱必妥相当(P>0.05)。西妥昔单抗可抑制由表皮生长因子(EGF)引发的EGFR自体磷酸化,基于对EGFR磷酸化抑制而建立的西妥昔单抗生物学活性方法与西妥昔单抗的肿瘤细胞生长抑制作用进行了比较,结果显示西妥昔单抗抑制EGFR磷酸化的活性数值与其抑制细胞生长的活性一致。在鼠异体移植模型中,西妥昔单抗对A431细胞的肿瘤生长产生强烈抑制作用,对HT-29细胞的肿瘤生长也有剂量依赖性抑制。结论:采用的检测方法可用于西妥昔单抗的生物学活性分析,其体内与体外生物学效应与市售爱必妥没有差异。

Objective：To analyze in vitro and in vivo bio-activities of new cetuximab,a bio-similar version of commercial anti-cancer drug Erbitux.Methods：The bio-activities of new cetuximab was examined by EGFR binding assay,SPR,EGFR phosphorylation inhibition assay and cell growth inhibition method.In vitro measurement of bio-activity in relationship with clinical efficacy was discussed by mouse xenograft model.Results：The newly-developed cetuximab aligns with Erbitux in target binding affinity（P＞0.05）,and possessed equal ability in inhibiting EGFR tyrosine auto-phosphorylation.The potency of cetuximab measured by the EGFR phosphorylation inhibition assay was consistent with results of cell growth inhibition method.By mouse xenograft,strong inhibition of A431cell xenograft was showed,indicating in vivo anti-cancer effect of cetuximab,and dose-dependent blockade of HT29 tumor growth was also observed.Conclusion：Data collectively demonstrate that cetuximab has similar biological effect with Erbitux.