Hori T
Department of Biological Responses, Kyoto University.
Rinsho Byori. 1993 Sep;41(9):959-65.
The sequence of events that accompany development of immature T cell precursors in man is not precisely known. Recently, we identified subpopulations of thymocytes that may represent intermediate stages between CD3-CD4-CD8- (TN) and CD3+CD4+CD8+ (DP) thymocytes. Multicolor analysis provided evidence for the existence of CD3-CD4+CD8- and CD3-CD4+CD8 alpha+beta- populations. In vitro culture of TN thymocytes with IL-7 gave rise to cells of these phenotypes, suggesting that the novel subpopulations we found are the progeny of TN thymocytes. Expression of CD34 was detected on most of TN thymocytes and progressively reduced as cells differentiate. The novel subpopulations were shown to express CD34. 6-22-week-old human fetal liver cells were also analyzed in search for the possible prethymic T cell precursors. It was revealed that most of CD3-CD7+ cells which had been considered as T cell precursors were CD34-CD56+ and exhibited non-MHC-restricted cytotoxicity. Thus, although they expressed cytoplasmic CD3 antigens, these cells seemed to represent NK cells rather than T cell precursors. Existence of the latter is still to be demonstrated.
人类未成熟T细胞前体发育过程中伴随的一系列事件尚不完全清楚。最近，我们鉴定出了胸腺细胞亚群，它们可能代表CD3-CD4-CD8-（TN）和CD3+CD4+CD8+（DP）胸腺细胞之间的中间阶段。多色分析为CD3-CD4+CD8-和CD3-CD4+CD8αβ-群体的存在提供了证据。用IL-7体外培养TN胸腺细胞可产生这些表型的细胞，这表明我们发现的新亚群是TN胸腺细胞的后代。在大多数TN胸腺细胞上检测到CD34的表达，并且随着细胞分化其表达逐渐降低。新亚群被证明表达CD34。我们还分析了6-22周龄的人类胎儿肝细胞，以寻找可能的胸腺前T细胞前体。结果显示，大多数被认为是T细胞前体的CD3-CD7+细胞是CD34-CD56+，并表现出非MHC限制性细胞毒性。因此，尽管这些细胞表达细胞质CD3抗原，但它们似乎代表NK细胞而非T细胞前体。后者的存在仍有待证实。
