中文摘要：

目的：以放射线处理建立小鼠淋巴细胞减少症模型并探讨其免疫学意义。方法：1．25Gy放射剂量照射C57BL／6小鼠，不同时问点计数外周血、脾脏和淋巴结中免疫细胞数，FACS动态分析各淋巴细胞亚群比例改变，RT—PCR检测淋巴细胞中转录因子T—bet、GATA-3的表达。进一步以DC—gp100瘤苗免疫放射处理小鼠，B16F10黑素瘤细胞攻击，观察肿瘤生长的大小。结果：放射线处理后小鼠淋巴细胞数显著减少，CD4^＋CD25^＋T细胞比例明显降低；CD44^highCD62^how记忆样T淋巴细胞形成；T-bet表达明显上调，GATA-3表达无明显改变。与未照射组比较，放射处理小鼠经DC—gp100瘤苗免疫后具有增强抵抗B16F10黑素瘤细胞攻击的效应，肿瘤生长明显减缓。结论：以放射线处理成功建立淋巴细胞减少症模型，并具有增强免疫保护的效应。

英文摘要：

Objective： To establish a mouse lymphopenia model via irradiation and to study its immune characteristics. Methods： Lymphocytes isolated from PBMC, spleen and inguinal lymph-nodes were counted after C57BL/6 mice were treated with irradiation at the dosage of 1.25 Gy. Subsets of lymphocytes were analyzed by FACS. The expression of transcription factors T-bet and GATA-3 were detected by RT-PCR. Irradiated mice treated with DC-gpl00 vaccine were challenged by B16F10 tumor cells, tumor growth was observed. Results： 1.25 Gy irradiation significantly decreased the cell number of lymphocytes, specially the subset of CD4^＋ CD25^＋ T cells. A memory-like T subset was induced during the course of immune reconstitution. The expression of T-bet but not GATA-3 in the splenocytes was up-regulated. Irradiated mice vaccinated with DC-gp100 could resist the tumor challenge and retard the tumor growth. Condusion： Lymphopenia mouse model is successfully established and .an enhanced immune protection can be induced under the lymphopenia status.