淋巴结在淋巴循环、免疫活动和肿瘤转移中起着重要作用，但其退化机理尚需深入研究。文献证实在正常人体内，部分实质性淋巴结存在退化现象。我们的前期研究显示在老年尸体头颈部存有较多各类（不同退化程度的）透明淋巴结。预实验证实，在老年尸体其他浅表部位和大鼠体内同样可发现透明淋巴结。据此，我们提出假设：淋巴结退化呈现渐进性过程；随着结内组织和超微结构的质和量的渐进性退变，最终导致淋巴结完全退化。本项目拟使用常规切片染色、电镜超微结构观察和相关蛋白表达的免疫荧光染色对不同年（月）龄组的人和大鼠体内正常及各类退化淋巴结的分布、形态超微结构和相关蛋白质表达进行系统研究，并比较正常的和不同退化阶段的淋巴结内相关蛋白质表达的差异；通过大鼠接触性超敏反应实验阐述退化淋巴结与免疫功能的相关性。明确在不同年（月）龄阶段体内退化淋巴结的分布，确立其形态学分型。为临床上肿瘤和其他淋巴相关疾病诊疗方案的制定提供理论证据。

Lymph node plays an important role in the lymphatic circulation, immune activity and cancer metastasis, but its degenerating mechanism needs further study. Literatures have showed that some of solidified lymph nodes presented degenerating nature in the normal human body. Our previous studies have shown that there were various types (in different degenerating stages) of transparent lymph nodes in the head neck region of the elderly cadavers. Preliminary experiments confirmed that transparent lymph nodes could be found in the other superficial parts of the elderly cadavers and rats. Accordingly, we hypothesize that: the degenerating process of the lymph node evolves progressively; with the progressive degeneration of the nodal tissue and ultrastructure in quality and quantity, the lymph node will be degenerated completely at last. In this project we intend to: determine the distribution, morphology-ultrastructrure and the difference of protein expression in the normal and all kinds of degenerated lymph nodes in different age groups of human cadavers and rats by using methods of the routine HE staining, electron microscope and immunohistochemistry；elaborate the correlation between the degenerating lymph node and immune function by Rats Contact Hypersensitivity test. It will clarify and establish the distribution and the morphologic classification of the degenerating lymph nodes in different age groups of the body to provide theoretical evidence for the clinic management of tumor and lymphatic related diseases.