Department of Stem Cell Transplantation & Cellular Therapy, University of Texas MD Anderson Cancer Center, Houston, TX 77030-4009, USA.
Cancer Res. 2011 Jul 15;71(14):5040-9. doi: 10.1158/0008-5472.CAN-11-0842. Epub 2011 Jun 6.
Autologous peripheral blood progenitor cell (PBPC) transplantation is the treatment of choice for selected myeloma patients. However, tumor cells contaminating the apheresis product are a potential source of relapse. Here we report a sequential purging strategy targeting mature and immature clonogenic myeloma cell populations in the autograft. Thawed PBPC products of myeloma patients were treated with rituximab to kill CD138(-)20(+) B cells (highly clonogenic immature cells), and bortezomib to target CD138(+) cells (normal and differentiated myeloma plasma cells), followed by coculture with allogeneic mesenchymal stem cells (MSC) from normal donors. After 7 days of coculture, nonadherent cells were removed and cultured in the absence of MSC for an additional 7 days. Then, efficacy of purging (removal of CD138(-)20(+) and CD138(+) cells) was assessed by flow cytometry and PCR. We used our ex vivo purging strategy to treat frozen aphereses from 16 patients. CD138(+) and CD138(-)20(+)(19(+)) cells present in the initial products were depleted more than 3 and 4 logs, respectively based on 10(6) flow-acquisition events, and to levels below the limit of detection by PCR. In contrast, total nucleated cell (TNC), CD34(+) cell, and colony-forming cell numbers were increased by approximately 12 to 20, 8-, and 23-fold, respectively. Overall, ex vivo treatment of apheresis products with rituximab, bortezomib, and coculture with normal donor MSC depleted mature and immature myeloma cells from clinical aphereses while expanding the normal hematopoietic progenitor cell compartment.
自体外周血造血祖细胞（PBPC）移植是治疗选择的多发性骨髓瘤患者的首选。然而，污染的单采产品中的肿瘤细胞是疾病复发的潜在来源。在这里，我们报告了一种针对自体移植中成熟和不成熟克隆性骨髓瘤细胞群体的连续净化策略。多发性骨髓瘤患者的解冻 PBPC 产品用利妥昔单抗处理以杀死 CD138(-)20(+)B 细胞（高度克隆性不成熟细胞），并用硼替佐米靶向 CD138(+)细胞（正常和分化的骨髓瘤浆细胞），然后与来自正常供体的同种异体间充质干细胞（MSC）共培养。共培养 7 天后，去除非贴壁细胞，并在没有 MSC 的情况下再培养 7 天。然后，通过流式细胞术和 PCR 评估净化效果（去除 CD138(-)20(+)和 CD138(+)细胞）。我们使用我们的体外净化策略来治疗 16 名患者的冷冻单采。根据 10(6)个流式细胞术采集事件，初始产品中存在的 CD138(+)和 CD138(-)20(+)(19(+))细胞分别被耗尽了 3 个和 4 个对数级，且低于 PCR 的检测限。相比之下，总核细胞（TNC）、CD34(+)细胞和集落形成细胞的数量分别增加了约 12 至 20、8 和 23 倍。总体而言，用利妥昔单抗、硼替佐米和正常供体 MSC 共培养对单采产品进行体外处理，可从临床单采中清除成熟和不成熟的骨髓瘤细胞，同时扩增正常造血祖细胞。
