动物细胞系的染色体组型与遗传变异率分析

Analyses of Chromosomal Karyotypes and Cytogenetic Variations of Animal Cell Lines

在建立国内首家犬、猫、猴、鼠传代细胞库，即７种动物肾细胞系（Ｆ－８１、ＣＲＦＫ、ＭＤＣＫ、Ｖｅｒｏ、Ｖｅｒｏ－２、ＭＡ－１０４、ＢＨＫ－２１）的种子库和工作库的基础上，通过细胞染色体组型、Ｇ带核型、染色体数目变异率、结构畸变率分析，了解７种细胞系传代培养不同代次的染色体变异情况。以相应的细胞株皮下接种裸鼠形成肿瘤实验、软琼脂细胞克隆形成率与植物凝集素作用下细胞凝集实验为对照，筛选出无致癌／致瘤性、符合细胞遗传学要求、无传染因子污染的细胞系（Ｆ－８１、ＣＲＦＫ、Ｖｅｒｏ、Ｖｅｒｏ－２）或极低致癌性的ＭＤＣＫ细胞系用于制苗，发现肿瘤细胞系高变异率株可在裸鼠体内快速选育成功。细胞系染色体遗传特征决定致瘤性质并具有种属特异性，得到一些１００％成瘤和１００％不成瘤的细胞株并探讨了与染色体组型的关系。对于肿瘤的发病机理及实验治疗，都是非常好的模型。一些细胞系不仅成瘤而且还可转移（致恶性横纹肌样瘤的ＢＨＫ－２１和Ｖｅｒｏ细胞株），其他致瘤细胞株只成瘤不转移或不明显转移。

After the master cell stock(mcs) and working cell bank of more than 30 different strains of 7 animal kidney cell lines (F-81 or CRFK cell line, MDCK cell line, Vero or Vero-2 cell line, MA-104 cell line and BHK-21 cell line) were established in China, the chromosomal number variations and structural aberrations of the above lines, primary feline or canine kidney cell (FKC or CKC) and HeLa cell line were investigated and their karyotypes of routine or Giemsa chromosomal bands were analyzed. The c arcinogenesis or tumorigenicity testing of these cells in about 700 nude mice and for colony formation in soft agar (SA) and for agglutination under different concentration of plant lectins was carried out. Both tumorigenicity-negative strains of F-81, CR FK, Vero or Vero-2 lines and very-low-tumorigenicity strains of MDCK line were successfully selected and evaluated for the production of canine or feline combination viral vaccines, which are free of infectious agents, and described with respect to cytoge netic characteristics and tumorigenicity. Rate of modal chromosome number represents the ratio of cell number having modal chromosome number to all the split cell number analyzed at random. Rate of difference represents the ratio of difference of the rate of modal chromosome number between mcs (master cell stock)＋n and mcs passages. The chromosomal analysis results showed that the ratio of difference of the rate of modal chromosome number between mcs＋n and mcs passages was not more than 5%～15% and the structure aberrations was generally 0%～3%, not more than 5%～10%, thus the hereditary character of cell lines is comparatively stable without significant difference between different passages. The genetic characteristics of chromosomal number of cell lines determines their tumorigenicity, but it is speciesspecific. Expe rimental models were established for the researches on the prevention and prophylaxis of malignant tumors or cancers and their genetically biological characteristics. Tests showed that there was correlation among cell line chromosome number variations, an chorage independence in soft agar, agglutination under plant lectins and tumor-forming ability in nude mice. Since testing in vitro is more economic, simpler, faster, and is thought to be reliable, we recommend plant lectins followed by SA or analysis of karyotypes as the initia l means for monitoring tumorigenicity of animal cell line in nude mice.