Lee C K, Kim K, Geiman T M, Murphy W J, Muegge K, Durum S K
Laboratory of Immunoregulation, Division of Basic Sciences, National Cancer Institute, Frederick, Maryland 21702-1201, USA.
Cell Immunol. 1999 Feb 1;191(2):139-44. doi: 10.1006/cimm.1998.1423.
Thymic progenitors have the capacity to generate alphabeta T cells, gammadelta T cells, and NK cells. To determine whether these three lineages derive from a single precursor cell or from different precursors, a procedure was developed for cloning precursor cells from mouse embryonic thymus. The progeny of each pro-T cell clone were then tested for the potential to generate alphabeta, gammadelta, and NK cells. Of these precursor clones, about half displayed dual potential, developing into either T cells or NK cells, demonstrating the existence of a common T/NK precursor cell in the thymus. The other half of the clones were restricted to T cell development. No precursor clones were restricted to NK development. The common T/NK precursors were shown to be of the pro-T1 (CD25(-)) stage whereas the T-restricted precursors were shown to be of the later pro-T2 (CD25(+)) stage. Both alphabeta and gammadelta T cells were generated from all clones derived from either pro-T1 or -T2 precursors. This shows that commitment of a cell to the alphabeta versus gammadelta lineages does not precede rearrangement of the TCR genes (which occurs immediately after the pro-T2 stage).
胸腺祖细胞有能力产生αβ T细胞、γδ T细胞和自然杀伤细胞（NK细胞）。为了确定这三个谱系是源自单个前体细胞还是不同的前体细胞，研究人员开发了一种从小鼠胚胎胸腺中克隆前体细胞的方法。然后，对每个前T细胞克隆的子代进行检测，以确定其产生αβ、γδ和NK细胞的潜力。在这些前体克隆中，约一半表现出双潜能，可发育为T细胞或NK细胞，这表明胸腺中存在共同的T/NK前体细胞。另一半克隆则局限于T细胞发育。没有前体克隆局限于NK细胞发育。共同的T/NK前体显示处于前T1（CD25(-)）阶段，而T细胞受限的前体则处于较晚的前T2（CD25(+)）阶段。αβ和γδ T细胞均由源自前T1或前T2前体的所有克隆产生。这表明细胞向αβ与γδ谱系的分化发生在TCR基因重排之前（TCR基因重排在前T2阶段之后立即发生）。
