PREDICTIVE SCREENING ASSAY FOR RADIATION INDUCED DAMAGES CAUSED BY CLINICAL RADIOTHERAPY

我们利用体外培养的人细胞系，研究了辐射诱发继发性恶性病变的预测方法。以前，我们报道了重离子束和X射线在细胞受到照射时的突变诱导(HPRT位点)的比较。本文报道了人淋巴细胞在全身照射(TBI)前后的染色体畸变率(双着丝粒和断片)。伤后多次抽血，分离淋巴细胞，Giemsa染色观察。我们还在TBI前采集了患者的淋巴细胞，然后在相同的TBI程序下对它们进行照射，并在*相同的实验中进行评估。双着丝粒频率和片段数量与体内和体外研究的辐射剂量都有很好的相关性(图1.2)。我们的实验结果表明，该检测系统适用于放射治疗患者的淋巴细胞。

We have studied the prediction assay of radiation induced secondary malignancy by using in vitro human cell lines. Previously, we reported the comparison of the mutation induction (hprt locus) by heavy ion beams and X-rays when cells were irradiated. In this report, we described the chromosomal aberration (dicentric and fragment) of human lymphocyte taken from patients before and after total body irradiation (TBI). Bloods were drawn several times during the TBI and lymphocytes were isolated, and then observed by Giemsa-staining. We also took lymphocytes from patients before TBI, and then they were irradiated under the same schedule of TBI, and evaluated in * same assay. The dicentric frequencies and fragment numbers were well related with radiation dose both in vivo (TBI) and in vitro studies (figure1.2). Our experimental results indicated that this assay system would be applicable to lymphocytes from patients who receive irradiation therapy.