Snoeij N J, Bol-Schoenmakers M, Penninks A H, Seinen W
Veterinary Pharmacology, Pharmacy and Toxicology, State University, Utrecht, The Netherlands.
Int J Immunopharmacol. 1988;10(1):29-37. doi: 10.1016/0192-0561(88)90147-6.
Using centrifugal elutration, rat thymocytes were separated into three fractions by size. Fraction 1 (F1) consisted of a large population (greater than 88% of all cells) of small, nonproliferating thymocytes. Fraction 2 (F2; 7% of all cells) was enriched in medium-sized thymocytes and showed an increased macromolecular synthesis. In the small fraction 3 (F3; less than 5% of all cells), large thymocytes, monocytes, granulocytes and cells in mitosis were concentrated. F3 demonstrated the highest proliferative activity. Fractions were characterized by size, cell morphology, DNA, RNA and protein synthesis and steady state ATP levels. The effects of the inhibitor of oxidative phosphorylation, tri-n-butyltin chloride (TBTC) on ATP levels and the incorporation of DNA, RNA and protein precursors were investigated for each thymocyte fraction. Although ATP levels increased with increasing thymocyte volume, TBTC reduced ATP levels in each subfraction proportionally. The incorporation of thymidine and leucine was markedly reduced in all fractions by TBTC, but not to the same extend. Dependent on the TBTC concentration, the rapidly proliferating cells of F2 and F3 were less affected compared to the noncycling cells of F1. The incorporation of uridine in the unfractionated cells and in F2 and F3 was also decreased by TBTC. However, at concentrations between 0.1 and 1 microM, TBTC stimulated uridine incorporation in the small thymocytes of F1. Therefore, fractionation of thymocyte suspensions was necessary to detect differential effects of TBTC on subpopulations. Centrifugal elutriation was found to be a useful tool with which to obtain subfractions of isolated rat thymocytes.
利用离心淘析技术，根据大小将大鼠胸腺细胞分离为三个组分。组分1（F1）由大量（占所有细胞的88%以上）小的、不增殖的胸腺细胞组成。组分2（F2；占所有细胞的7%）富含中等大小的胸腺细胞，且大分子合成增加。在小的组分3（F3；占所有细胞的不到5%）中，大胸腺细胞、单核细胞、粒细胞和处于有丝分裂期的细胞被富集。F3表现出最高的增殖活性。各组分通过大小、细胞形态、DNA、RNA和蛋白质合成以及稳态ATP水平进行表征。研究了氧化磷酸化抑制剂三丁基氯化锡（TBTC）对每个胸腺细胞组分的ATP水平以及DNA、RNA和蛋白质前体掺入的影响。尽管ATP水平随胸腺细胞体积的增加而升高，但TBTC按比例降低了每个亚组分中的ATP水平。TBTC使所有组分中胸苷和亮氨酸的掺入显著减少，但减少程度不尽相同。取决于TBTC浓度，与F1的非循环细胞相比，F2和F3中快速增殖的细胞受影响较小。TBTC也降低了未分离细胞以及F2和F3中尿苷的掺入。然而，在0.1至1 microM的浓度范围内，TBTC刺激了F1中小胸腺细胞中尿苷的掺入。因此，对胸腺细胞悬液进行分级分离对于检测TBTC对亚群的不同影响是必要的。发现离心淘析是获得分离的大鼠胸腺细胞亚组分的有用工具。
