关键词: 60Co γ射线, 淋巴细胞株, GDF15基因, mRNA

Abstract: OBJECTIVE: To investigate the changes of GDF15 mRNA expression in lymphoblastoid cells induced by ionizing radiation, in order to provide scientific evidence for gene expression as a biomarker in radiobiodosimetry. METHODS: Lymphoblastoid cells were irradiated by 60Co γ_rays with doses ranging from 0 to 15 Gy, and cultivated for different periods from 4 to 72 hours. The GDF15 mRNA levels in lymphoblastoid cells were analyzed with real_time PCR. RESULTS: After irradiation, the GDF15 mRNA level was enhanced gradually to peak at some dose, and then decreased in all time groups except the 12 h group. In the 12 h group, the GDF mRNA level increased significantly; the dose_effect fitted a linear model: y=1.046 9x＋0.527 8(R2=0.945 7，P<0.05). The changes of GDF15 mRNA levels varied at different time_points. After irradiation of 8 Gy, GDF15 mRNA level rose significantly and peaked at 12 h. CONCLUSION: The enhanced GDF15 mRNA level induced by ionizing radiation depended on the exposed dose and duration.

Key words: 60Co γ_rays, lymphoblastoid cell line, GDF15 gene, mRNA