Katsura Y, Kina T, Amagai T, Tsubata T, Hirayoshi K, Takaoki Y, Sado T, Nishikawa S I
J Immunol. 1986 Oct 15;137(8):2434-9.
Stem cell activities of bone marrow, spleen, thymus, and fetal liver cells for T cell lineage were studied comparatively by transferring the cells from these organs through i.v. or intrathymus (i.t.) route into right leg- and tail-shielded (L-T-shielded) and 900 R-irradiated recipient mice, which were able to survive without supplying hemopoietic stem cells. Cells from B10.Thy-1.1 (H-2b, Thy-1.1) mice were serially diluted and were transferred into L-T-shielded and irradiated C57BL/6 (H-2b, Thy-1.2) mice, and 21 days later the thymus cells of recipient mice were assayed for Thy-1.1+ cells by flow cytofluorometry. The percentage of recipient mice possessing donor-type T cells was plotted against the number of cells transferred, and the stem cell activity in each cell source was expressed as the 50% positive value, the number of donor cells required for generating donor-type T cells in the thymuses of 50% of recipient mice. In i.v. transfer experiments, the activity of bone marrow cells was similar to that of fetal liver cells, and about 100 times and nearly 1000 times higher than those of spleen cells and thymus cells, respectively. In i.t. transfer experiments, the number of cells required for generating donor-type T cells was much lower than that in i.v. transfer experiments, although the ratio in 50% positive values between i.v. and i.t. transfers differed among cell sources. In i.t. transfers, the 50% positive value of bone marrow cells was five times, 400 times, and 500 times higher than that of fetal liver cells, spleen cells, and thymus cells, respectively. Our previous finding that stem cells are enriched in the spleens of mice which were whole body-irradiated and marrow-reconstituted 7 days earlier was confirmed also by the present limiting dilution assay carried out in i.v. as well as i.t. transfers.
通过将来自这些器官的细胞经静脉内（i.v.）或经胸腺内（i.t.）途径注入右下肢和尾部屏蔽（L-T屏蔽）且经900拉德照射的受体小鼠体内，对骨髓、脾脏、胸腺和胎肝细胞在T细胞谱系方面的干细胞活性进行了比较研究，这些受体小鼠在不供应造血干细胞的情况下也能够存活。将来自B10.Thy-1.1（H-2b，Thy-1.1）小鼠的细胞进行连续稀释，并注入L-T屏蔽且经照射的C57BL/6（H-2b，Thy-1.2）小鼠体内，21天后通过流式细胞荧光术检测受体小鼠胸腺细胞中的Thy-1.1+细胞。将拥有供体型T细胞的受体小鼠的百分比与转移的细胞数量作图，每种细胞来源的干细胞活性以50%阳性值表示，即50%的受体小鼠胸腺中产生供体型T细胞所需的供体细胞数量。在静脉内转移实验中，骨髓细胞的活性与胎肝细胞相似，分别比脾细胞和胸腺细胞高约100倍和近1000倍。在经胸腺内转移实验中，产生供体型T细胞所需的细胞数量比静脉内转移实验中的要低得多，尽管静脉内和经胸腺内转移之间50%阳性值的比例在不同细胞来源中有所不同。在经胸腺内转移中，骨髓细胞的50%阳性值分别比胎肝细胞、脾细胞和胸腺细胞高5倍、400倍和500倍。我们之前的发现，即干细胞在7天前接受全身照射并进行骨髓重建的小鼠脾脏中富集，在本次静脉内以及经胸腺内转移的有限稀释实验中也得到了证实。
