淋巴类细胞的干细胞出骨髓后就分成两个系列,T细胞前体和B细胞前体。T系列细胞在胸腺激素作用下,由未成熟的皮质细胞逐步成为较成熟的髓质细胞,最后迁出胸腺在周围淋巴类组织进一步成熟分化成为具有功能细胞亚群。目前对此途径远未阐明,涉及多种细胞和因子的相互作用。近年来除胸腺 Lymphoid stem cells differentiate into two series, T-cell precursors and B-cell precursors. Under the action of thymus hormones, T cells gradually become immature cortical cells into mature mature medulla cells. Finally, the thymus is removed and further differentiated to become a functional cell subpopulation in the peripheral lymphoid tissues. The current approach is far from elucidated, involving a variety of cell and factor interactions. In addition to thymus in recent years