摘要用免疫组织化学及流式细胞计（FACS）对抗小鼠胸腺基质细胞（Thymic stromal cells，TSC）的单克隆抗体PF18-3进行了系统研究。免疫组织化学结果：PF18-3与小鼠胸腺髓质TSC和皮质胸腺细胞呈阳性反应；FACS分析显示，在活细胞染色时，PF18-3不能与膜表面分子结合，经甲醛固定丙酮增加细胞膜通透性后才能使各免疫细胞亚群呈阳性反应，固定后细胞染色结果为：胸腺细胞中，PF18-3 +细胞为84.4%；在分离的CD4 -8 -、CD4 +8 -、CD4 -8 +胸腺细胞中，PF18-3 +细胞分别为2%，69.3%，62%；在脾、颌下淋巴结、外周血淋巴细胞中，PF18-3 +细胞分别为37.9%，51.5%，26.7%；PF18-3 +CD3 +双阳性细胞在总T淋巴细胞中分别占54.6%，59.8%，20.2%；PF18-3 +B220 +细胞在总B细胞中分别占35.1%，38.1%，37.6%；PF18-3对大部分巨噬细胞（71.6%）和极少数粒细胞（6.1%）也呈阳性反应。以上结果说明PF18-3识别的抗原主要分布于胸腺基质细胞膜表面和胸腺及外周免疫细胞的胞浆。提示它可能介导了TSC诱导的T细胞发育；可能也参与了免疫反应中不同种类细胞间的相互作用。

abstractsPF18-3, a McAb specific for MTSC (mouse thymic stromal cells) was investigated by means of immunohistochemistry and FACS analysis. Results indicated that PF18-3 recognized the molecules expressed on MTSC and cortical thymocytes. FACS analysis showed that 84.4% of thymocytes and 37.9% of splenic cells were PF18-3 positiive. 54.6% of splenic T cells were PF18-3 +CD3 +double positive cells; 51.5% of lymphocytes in lymph node were positive cells, 59.8% of T lymph node cells expressed PF18-3 +CD3 +. In peripheral blood lymphocytes, there were 26.7% of cells labelled with PF18-3, 20.2% of these T cells expressed PF18-3 +CD3 +; 71.6% of macrophages and 6.1% of granulocytes were also stained with PF18-3. These results suggest that MTSC shares an antigen with other types of cells. This shared antigen between MTSC and thymocytes may mediate interaction for the induction of T cell development and for the activation of various types of cells involved in immune response.