小鼠CD3^+TCRαβ^+CD4^-CD8^-胸腺细胞特性分析

Characterization of murine CD3^+TCRαβ^+CD4^-CD8^- thymocytes

目的 分析CD3+ TCRαβ+ DN(doublenegative)胸腺细胞的特性 ,推断其在胸腺发育中表型和功能的成熟过程。方法 分离纯化小鼠胸腺DN细胞 ,用多重染色的方法分析CD3+ TCRαβ+ DN细胞的表型和TCR库 ,并与外周淋巴结的相应细胞进行对比。结果 DN胸腺细胞为异质性细胞 ,包括CD3-DN细胞和CD3+ DN细胞 ,而CD3+ DN细胞又分为CD3+ TCRαβ+ 和CD3+ TCRγδ+ 2个亚群。其中 ,CD3+ TCRαβ+ DN细胞体积较小 ,绝大部分细胞对可的松耐受 ,细胞中能与自身反应的Vβ3+ 和Vβ11+ 细胞比例极低 ,表型较为成熟 ,与髓质型SP(singlepositive)细胞相当。结论 CD3+ TCRαβ+ DN细胞不同于CD3-TCRαβ-DN细胞 ,是一个独特的细胞亚群 ,只有在经历表型和功能的进一步成熟后才能迁出胸腺 。

Objective To analyze the characteristics of murine CD3 +TCRαβ + DN thymocytes and deduce their phenotypic and functional process in the thymus. Methods Murine DN thymocytes were purified and multi color staining was used to analyze the phenotype and TCR repertoire of CD3 +TCRαβ + DN cells. Results DN thymocytes are heterogeneous containing both CD3 - DN and CD3 + DN cells. CD3 + DN thymocytes can also be classified into two subsets as CD3 +TCRαβ + and CD3 +TCRγδ +. CD3 +TCRαβ + DN thymocytes are small and most of them are cortisone resistant. The percentage of self reactive Vβ3 + and Vβ11 + among these cells is low. The phenotype of CD3 +TCRαβ + DN thymocytes is quite mature, correspondence to that of medullary type SP thymocytes. Conclusions Unlike CD3 -TCRαβ - DN thymocytes, CD3 +TCRαβ + DN thymocyte population is a unique subset. They will undergo a phenotypic and functional maturation process before leaving thymus and entering into periphery zone. [