Like all hematopoietic cells, T lymphocytes are derived from bone-marrow-resident stem cells. However, whereas most blood lineages are generated within the marrow, the majority of T cell development occurs in a specialized organ, the thymus. This distinction underscores the unique capacity of the thymic microenvironment to support T lineage restriction and differentiation. Although the identity of many of the contributing thymus-derived signals is well established and rooted in highly conserved pathways involving Notch, morphogenetic, and protein tyrosine kinase signals, the manner in which the ensuing cascades are integrated to orchestrate the underlying processes of T cell development remains under investigation. This review focuses on the current definition of the early stages of T cell lymphopoiesis, with an emphasis on the nature of thymus-derived signals delivered to T cell progenitors that support the commitment and differentiation of T cells toward the alphabeta and gammadelta T cell lineages.

中文翻译：

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胸腺是T淋巴细胞生成的诱导位点。

像所有造血细胞一样，T淋巴细胞衍生自骨髓驻留干细胞。然而，尽管大多数血统是在骨髓内产生的，但大多数T细胞发育却发生在特殊的器官胸腺中。这种区别强调了胸腺微环境支持T谱系限制和分化的独特能力。尽管许多贡献的胸腺来源信号的身份已经很好地确立，并且根源于涉及Notch，形态发生和蛋白质酪氨酸激酶信号的高度保守的途径，但随后的级联整合方式协调了T细胞发育的潜在过程仍在调查中。这篇评论着重于目前对T细胞淋巴细胞生成的早期定义，