Hansson M, Svensson A, Engervall P
Immunhemotherapy unit, Karolinska Hospital, Stockholm, Sweden.
Med Oncol. 1996 Jun;13(2):71-9. doi: 10.1007/BF02993856.
The rapid development in the area of collecting and processing autologous peripheral blood stem cells (PBSC) is reflected by the escalating number of patients treated with PBSC, and by the increasing amount of literature on the subject. Clinical experience suggests that among the variables with a negative influence on mobilization of PBSC, the most important may be the amount of previous stem cell toxic chemotherapy. In selecting patients suitable for autologous PBSC support, the requirement of an adequate anti-tumor therapy has to be weighed against the risk of chemotherapy related stem cell toxicity which will result in inability to collect a sufficient amount of PBSC. The general consensus is that a sufficient PBSC-autograft should contain 2-5 x 10(6) CD34+/kg body weight, but attempts to provide a recommended optimal or threshold level are hampered by the lack of standardized methods for CD34+ cell enumeration. In addition, the time to haematological recovery depends both on the dose of infused CD34+ cells and also on the amount of previous chemotherapy, which affects both the quality of the graft and the supportive microenvironment of the host. The quality of the autograft may also be contaminated by malignant cells, even if the biological significance of tumor cell detection in the PBSC graft has not yet been established. Recent development of methods for in vitro purging and selection of CD34+ cells for clinical use have provided the means to avoid or reduce reinfusion of malignant cells. Future directions of clinical research include the ability to define and enumerate the proportion of stem cells versus committed progenitor cells among the CD34+ cells in a PBSC collection, which will be important to ensure rapid engraftment as well as long term haematopoiesis.
自体外周血干细胞（PBSC）采集和处理领域的快速发展体现在接受PBSC治疗的患者数量不断增加以及该主题的文献数量不断增多。临床经验表明，在对PBSC动员有负面影响的变量中，最重要的可能是既往干细胞毒性化疗的剂量。在选择适合自体PBSC支持的患者时，必须权衡充分的抗肿瘤治疗需求与化疗相关干细胞毒性风险，后者可能导致无法采集到足够数量的PBSC。普遍共识是，足够的PBSC自体移植应包含2 - 5×10⁶个CD34⁺/kg体重，但由于缺乏标准化的CD34⁺细胞计数方法，难以提供推荐的最佳或阈值水平。此外，血液学恢复时间既取决于输注的CD34⁺细胞剂量，也取决于既往化疗的剂量，既往化疗会影响移植物质量和宿主的支持性微环境。即使PBSC移植物中肿瘤细胞检测的生物学意义尚未确定，自体移植物的质量也可能被恶性细胞污染。用于临床的CD34⁺细胞体外净化和选择方法的最新进展提供了避免或减少恶性细胞回输的手段。临床研究的未来方向包括能够定义和计数PBSC采集中CD34⁺细胞中干细胞与定向祖细胞的比例，这对于确保快速植入以及长期造血至关重要。
