抗CD_3/抗CD_(20)微型双功能抗体裸鼠体内分布研究

目的：建立裸鼠皮下人Ｂ－淋巴细胞移植瘤模型，研究抗ＣＤ３／ＣＤ２０。微型双功能抗体在裸鼠体内的分布。方法：采用亲和层析分离纯化本室构建的抗 ＣＤ３／抗 ＣＤ２０微型双功能抗体可溶性表达产物，并用ＳＤＳ－ＰＡＧＥ、Ｗｅｓｔｅｒｎ ｂｌｏｔ、分子排阻层析和 ＦＡＣＳ鉴定纯化产物；采用５周龄左右的雌性 ＢＡＬＢ／ｃ－ｎｕ，经４Ｇｙ照射、皮下接种 Ｒａｊｉ细胞建立裸鼠皮下人Ｂ－淋巴细胞移植瘤模型，并于眼底静脉丛注射１２５Ｉ标记的抗ＣＤ３／抗ＣＤ２０微型双功能抗体，测定各组织中１２５Ｉ的分布。结果：雌性ＢＡＬＢ／ｃ－ｎｕ经照射、皮下接种１×１０～７～３×１０～７Ｒａｊｉ细胞／只，６～１４天均开始出现移植瘤，移植瘤细胞膜表面标记与 Ｒａｊｉ相同，且在２４小时时肿瘤部位１２５Ｉ的分布明显低于心、肝、肾、脾，其比值分别为０．０８、０．１９、０．０６和０．５１，而 ７２小时时肿瘤部位１２５Ｉ的分布则高于心、肝、肾、脾，其比值分别为 ２．３２、９．４６、８．２４和９．５０。结论：抗ＣＤ３／抗ＣＤ２０微型双功能抗体能在裸鼠皮下人Ｂ－淋巴细胞移植瘤部位富集，是一个有望用于Ｂ细胞恶性肿瘤临床治疗的双特异性抗体。

Distribution of Anti-CD_3/CD_(20) Diabody in Human Lymphoma Nude Mouse Xenograft Model

Objective: To study the development of human Raji tumor cell nude mouse xenograft model in order to research distribution of Anti-CD3/CD20 Diabody (Diabody) in nude mouse. Methods: The Diabody was purified by affinity chromatography and analysed by both the detection of Western blot, size exclusion chromatography and FACS. Human Raji cells were inoc- ulated into nude mouse subcutaneously, 3 days after irradiation with 4-Gy dose, the 125I-Diabody, K was injected when tumor volume reached about 100mm3, Results: All nude mice grafted with Raji cell line grown tumor, the rate of tumor growing was 100 percent. Both the tumor cells in vivo and Raji cells produced same antigens. Distribution of 72h 125I-Diabody in tumor was high- er than in heart, liver, kidney and spleen and the ratio of them were 2.32, 9.46, 8.24 land 9.50 respectively. Conclusion: The anti-CD3/CD20 Diabody is able to be concentrated in B cell tumor in nude mouse xenograft model and is porved as a potent, anti-tumor agent for clinical therapy of human B cell lymphomas.