Background and objective: Radiation-induced lung injure is one of the major factors of limitation in radiotherapy for lung cancer. Whether the use of thymosin and radiotherapy simultaneously would increase the radiation-induced lung injure is unclear. The aim of this study is to evaluate the effects of thymosin alpha-1 on radiation induced pneumonitis in mice.
Methods: Three groups of mice, control (C), radiation alone (RT), thymosin alpha-1 plus radiation (T+RT), were entered into the study. The weight and mortality of mice, pleural effusion, quantity of protein and cell count in the bronchoalvealar lavage (BAL) and pulmonary fibrosis score were evaluated as the outcome measures.
Results: The mortality ratio of the T+RT and RT groups were 3/14, 2/10, respectively. The time of death were all in the 23-24 weeks after radiotherapy. There was no pleural effusion in the T+RT group other than 2/2 occurred in RT group. The quantity of protein, cell number and neutrophil number in the BAL and lung coefficient in mice of T+RT group were remarkably lower than that of RT group, but the BALF macrophages number was remarkably higher than that in RT group in the 8 weeks. The quantity of protein, cell number, neutrophil number and macrophages number in the BAL, lung coefficient, the scores of lung fibrosis in mice of T+RT group were significantly lower than that of RT group in the 24 weeks. All test data were lowest in mice of C group. And there was no obvious pulmonary fibrosis in the mice of C group.
Conclusions: Thymosin alpha-1 could relieve radiation-induced acute and late pulmonary injuries.
背景与目的: 放射性肺损伤是限制肺癌放疗疗效提高的主要因素之一，胸腺肽与放疗同时使用是否会加重放射性肺损伤尚不明确。本研究旨在用小鼠的放射性肺损伤模式评价α1胸腺肽对放射性肺损伤的影响。
方法: 33只雌性C57BL/6J鼠，体重19 g左右，分为正常空白对照（C）组、单纯照射（RT）组、α1胸腺肽加照射（T+RT）组。用小鼠死亡比例、体重、胸水、肺系数、肺泡灌洗液蛋白含量和细胞计数、肺泡壁肿胀和细胞浸润及肺纤维化积分作为观察指标来评价三组间的差异。
结果: T+RT组与RT组小鼠死亡比例分别为3/14、2/10，死亡时间均为23周-24周。第24周时解剖发现RT组有一侧大量胸腔积液，一侧中等量积液，T+RT组未见明显胸腔积液。T+RT组肺系数、肺泡灌洗液蛋白含量和细胞总数、中性粒细胞计数均在第8周低于RT组，但巨噬细胞数第8周时T+RT组高于RT组。第24周T+RT组肺系数、肺泡灌洗液蛋白含量和细胞总数、中性粒细胞数、肺泡壁肿胀和细胞浸润及肺纤维化积分均明显低于RT组。C组肺泡灌洗液蛋白含量和细胞总数、肺泡壁肿胀与炎性细胞浸润均较低，未发生明显肺纤维化。
结论: α1胸腺肽可能具有一定的防治放射性肺损伤的作用。