PULMONARY SURFACTANT SYSTEM AND RADIATION PNEUMONITIS

继发性肺炎和肺纤维化的频繁发生 放射治疗和/或化疗在癌症综合治疗中的应用 导致了对预测性指数的搜索。发病率和死亡率 在弥漫性肺炎或纤维化发作后高度和 在临床前阶段识别这一实体可能会允许 避免发病的干预措施。为此，我们一直在进行研究 以II型肺泡细胞为切入点理解辐射 肺炎。II型肺泡细胞已被证明是早期的靶点 照射后不久，就会将表面活性物质释放到肺泡内。 通过使用灌洗技术，肺泡表面活性物质已被证明是 肺照射后升高。发生肺性甲状腺肿4例 几个月后，在LAF小鼠中，表明与表面活性物质有很强的相关性 在7天和28天释放。出于这个原因，进一步的实验是 建议改善II型肺泡细胞的急性生化改变 作为对后续影响的预测。当在中标识这些更改时 在小鼠身上进行的体外和体内研究，它们将作为标志物在 较大的动物诊断模型(兔子和狗)在其 MAN中的介绍。辐射对人体健康影响的因果关系 II型肺泡细胞、其他肺细胞和肺炎及纤维化， 将在各种相关的生化、组织学和 超微结构技术。辐射响应的改性研究 通过不同的放射分割方案，对化疗和 辐射防护剂也将在研究中。表面活性剂，其 II型肺泡细胞其他变化的前体具有潜在的 是第一个晚期辐射效应的早期生化标志物。

The frequent occurrence of pneumonitis and pulmonary fibrosis secondary to radiation therapy and/or chemotherapy in combined modality cancer treatment has led to search for a predictive index. The morbidity and mortality after the onset of a diffuse pneumonitis or fibrosis is high and recognition of this entity in the pre-clinical phase may allow for interventions to avoid its onset. Toward this end, we have pursued studies on Type II pneumocyte as a beginning point to understand radiation pneumonitis. The Type II pneumocyte has been shown to be an early target of radiation and releases surfactant into alveoli shortly after exposure. By use of lavaging techniques, alveolar surfactant has been shown to be elevated after pulmonary irradiation. Pulmonary lethalith occurred four months later in LAF, mice, indicating a strong correlation with surfactant release at 7 and 28 days. For this reason, further experiments are proposed to refine the acute biochemical alterations of Type II pneumocytes as a predictor for later effects. When these changes are identified in in vitro and in vivo studies on mice, they will be studied as markers in larger animal diagnostic models (rabbits and dogs) prior to their introduction in man. The causal relationship between radiation effects on Type II pneumocytes, other pulmonary cells and pneumonitis and fibrosis, will be evaluated in a variety of correlated biochemical, histological and ultrastructural techniques. Studies on modification of radiation response by different radiation fractionation schema and to chemotherapeutic and radioprotective agents will also be under study. Surfactant, its precursors on other changes in Type II pneumocytes has the potential for being the first early biochemical marker for late radiation effects.