Buronfosse A, Thomas C P, Ginestet C, Doré J F
Laboratoire INSERM d'Immunologie et de Cancérologie Expérimentale, Lyon, France.
C R Acad Sci III. 1994 Nov;317(11):1031-41.
Cells obtained from a human glioblastoma (G5) were characterized and used to develop an assay measuring their radiosensitivity in vitro. Surviving fractions were estimated 12 days after irradiation by image analysis of the total surface occupied by the cells. This report evaluates 4 experimental factors which may influence the radiosensitivity in vitro of G5 cells: passage number, delay between plating and irradiation, cell density and clonal heterogeneity. The radiosensitivity of the G5 cell line was found to be passage-independent at least between passages 12 and 75. Experimental conditions influence the radiosensitivity as surviving fraction at 2 Gy (SF2) range from 90% (5,000 cells/well, irradiation 72 h after seeding) to 49% (2,500 cells per well, irradiation 24 h after seeding). The heterogeneity of the radiosensitivity is large at the clonal level as SF2 of six clones isolated from the G5 line were 45%, 50%, 72%, 74%, 79% and 84%. Finally, when G5 cells were irradiated at low cell density and at the beginning of the growth phase, the radiosensitivity measured with this assay is comparable to that obtained with a standard colony assay. We propose that this assay may be useful to determine the intrinsic radiosensitivity of cells obtained from human tumours.
从人胶质母细胞瘤（G5）获取的细胞进行了特征鉴定，并用于开发一种体外测量其放射敏感性的检测方法。通过对细胞占据的总表面积进行图像分析，在照射后12天估算存活分数。本报告评估了可能影响G5细胞体外放射敏感性的4个实验因素：传代次数、接种与照射之间的延迟、细胞密度和克隆异质性。发现G5细胞系的放射敏感性至少在第12代至第75代之间与传代无关。实验条件会影响放射敏感性，因为2 Gy时的存活分数（SF2）范围从90%（5000个细胞/孔，接种后72小时照射）到49%（2500个细胞/孔，接种后24小时照射）。在克隆水平上，放射敏感性的异质性很大，因为从G5细胞系分离的6个克隆的SF2分别为45%、50%、72%、74%、79%和84%。最后，当G5细胞在低细胞密度和生长阶段开始时进行照射，用该检测方法测得的放射敏感性与用标准集落形成检测方法获得的结果相当。我们认为该检测方法可能有助于确定从人类肿瘤获得的细胞的内在放射敏感性。
