Suzue T, Kawano Y, Takaue Y, Kuroda Y
Department of Pediatrics, University of Tokushima, Japan.
Exp Hematol. 1994 Aug;22(9):888-92.
Although there is a growing body of information available regarding restoration of hematopoiesis with peripheral blood stem cell (PBSC) autografts, few studies have explored this procedure using allografts. In this study with healthy donors, we investigated the feasibility of a protocol for mobilizing PBSC using recombinant human granulocyte colony-stimulating factor (G-CSF) and subsequent bulk depletion of T cells from apheresis-harvested cells. Nine informed healthy donors were given G-CSF subcutaneously at two different dosing schedules (5 micrograms/kg/d in five donors and 2 micrograms/kg/d in four) for 5 consecutive days, and serial changes in blood components, including hematopoietic progenitor cells, were monitored. After 5 days of stimulation with G-CSF, PBSCs were collected by apheresis, and yields were compared. The number of white blood cells (WBC) reached a plateau level on either day 2 (5 micrograms) or 3 (2 micrograms), but the numbers of red blood cells and platelets were not affected. Circulating colony-forming unit-granulocyte/macrophage (CFU-GM) levels started to increase 1 or 2 days after the increase in the WBC count. By performing a 3L apheresis, the number of CFU-GM harvested was 4.6 +/- 3.3 x 10(6) (mean +/- standard error of the mean [SEM]) in the 5-micrograms group and 1.8 +/- 0.7 x 10(6) in the 2-micrograms group. Different procedures for depleting T cells, including the use of L-phenylalanine methyl ester (PME) and flasks coated with anti-CD5/CD8 monoclonal antibodies or neuraminidase-treated sheep red blood cells (SRBC), were also tested on the harvested cells. We found that cell lysis with PME before selective removal of T cells was very effective in reducing the number of cells that required further processing and was suitable for routine use. However, our current procedure resulted in unsatisfactory depletion of T cells (99.5% removal) while retaining hematopoietic progenitor cells (7.5% recovery). Further research is required in this area.
尽管关于外周血干细胞（PBSC）自体移植恢复造血功能的信息越来越多，但很少有研究探讨同种异体移植的这种方法。在这项针对健康供体的研究中，我们调查了一种方案的可行性，该方案使用重组人粒细胞集落刺激因子（G-CSF）动员PBSC，并随后从单采收获的细胞中大量清除T细胞。9名知情的健康供体按照两种不同的给药方案皮下注射G-CSF（5名供体为5微克/千克/天，4名供体为2微克/千克/天），连续5天，并监测包括造血祖细胞在内的血液成分的系列变化。在用G-CSF刺激5天后，通过单采收集PBSC，并比较产量。白细胞（WBC）数量在第2天（5微克组）或第3天（2微克组）达到平台期水平，但红细胞和血小板数量未受影响。循环集落形成单位-粒细胞/巨噬细胞（CFU-GM）水平在WBC计数增加1或2天后开始升高。通过进行3L单采，5微克组收获的CFU-GM数量为4.6±3.3×10⁶（平均值±平均标准误差[SEM]），2微克组为1.8±0.7×10⁶。还对收获的细胞测试了不同的T细胞清除程序，包括使用L-苯丙氨酸甲酯（PME）以及用抗CD5/CD8单克隆抗体或神经氨酸酶处理的绵羊红细胞（SRBC）包被的培养瓶。我们发现，在选择性清除T细胞之前用PME进行细胞裂解在减少需要进一步处理的细胞数量方面非常有效，并且适合常规使用。然而，我们目前的程序导致T细胞清除效果不理想（清除率99.5%），同时造血祖细胞保留率为7.5%。该领域需要进一步研究。
