Mohr M, Hilgenfeld E, Fietz T, Hoppe B, Koenigsmann M, Hoffmann M, Knauf W U, Cassens U, Sibrowski W, Kienast J, Thiel E, Berdel W E
Department of Medicine/Hematology and Oncology, University of Münster, Germany.
Clin Cancer Res. 1999 May;5(5):1035-40.
We have established a new simultaneous positive/negative selection procedure using the Baxter Isolex 300i system. We tested its tumor cell (TC) purging efficacy by tumor contamination tests ex vivo and its safety in a group of 17 breast cancer (BC) patients by measuring hematopoietic recovery after high-dose (HD) therapy and autologous stem cell rescue with the selected cells. Tumor contamination tests resulted in a TC depletion of 4.1-6.0 log steps. The CD34+ cell yield in this experimental setting was 38.9-91.5%, and the CD34+ cell purity was 86.0-96.0%. In a group of 17 BC patients (5 high-risk adjuvant, > or = 10 lymph nodes positive, and 12 metastatic), we processed leukapheresis products (LPs) by simultaneous positive/negative selection. In these clinical samples, the mean CD34+ cell yield was 56.2% (range, 14.0-80.1%), and the CD34+ cell purity was 94.5% (range, 69.0-99.8%). Additionally, we screened samples of the patients' LPs before and after the purging procedure for contaminating TC by immunocytochemistry. In 15 of 17 tested cases, TCs were detectable prior to the purging procedure. After the procedure, we could not detect residual TCs in 16 of 17 cases. In one case, we found a highly reduced number of TCs. Furthermore, we evaluated the times for hematopoietic reconstitution in a group of five BC patients in the high-risk adjuvant situation who underwent HD chemotherapy and hematopoietic rescue with positive/negative selected stem cells and compared it with our own data from 10 BC patients who, after identical HD therapy, received only positively selected CD34+ cells and 14 patients who, after identical HD therapy, received autografts purged by incubation with toxic ether lipids (ET-18-OCH3). In all groups, a leukocyte count of >2000 cells/microl was reached at day +10. A platelet count of > 50,000 cells/microl was reached at day +12 in the ET-18-OCH3 group and at day +14 in the other two groups. Furthermore, 12 patients with metastatic disease rescued with positive/negative selected stem cells after HD therapy also showed fast and comparable hematopoietic recovery. The new simultaneous immunomagnetic positive/negative selection using a closed system is effective and safe. Processing LPs leads to a similar CD34+ cell yield, a higher TC depletion compared to standard CD34+ cell selection, and no delay in hematopoietic recovery.
我们使用百特Isolex 300i系统建立了一种新的同时进行阳性/阴性选择的程序。我们通过体外肿瘤污染试验测试了其清除肿瘤细胞（TC）的功效，并通过测量高剂量（HD）治疗后造血功能的恢复情况以及用所选细胞进行自体干细胞救援，评估了该程序在17例乳腺癌（BC）患者中的安全性。肿瘤污染试验导致TC减少了4.1 - 6.0个对数级。在该实验设置中，CD34 +细胞产量为38.9% - 91.5%，CD34 +细胞纯度为86.0% - 96.0%。在一组17例BC患者（5例高危辅助治疗患者，≥10个淋巴结阳性，以及12例转移性患者）中，我们通过同时进行阳性/阴性选择处理了白细胞分离产品（LP）。在这些临床样本中，CD34 +细胞的平均产量为56.2%（范围为14.0% - 80.1%），CD34 +细胞纯度为94.5%（范围为69.0% - 99.8%）。此外，我们通过免疫细胞化学方法在净化程序前后对患者LP样本进行筛查，以检测是否存在污染的TC。在17例测试病例中的15例中，净化程序前可检测到TC。程序后，17例病例中的16例未检测到残留的TC。在1例病例中，我们发现TC数量大幅减少。此外，我们评估了一组5例处于高危辅助治疗状态的BC患者在接受HD化疗并用阳性/阴性选择的干细胞进行造血救援后的造血重建时间，并将其与我们自己的两组数据进行比较，一组是10例BC患者，在接受相同的HD治疗后仅接受阳性选择的CD34 +细胞，另一组是14例患者，在接受相同的HD治疗后接受用有毒醚脂（ET - 18 - OCH3）孵育净化的自体移植物。在所有组中，在第10天白细胞计数均达到>2000个细胞/微升。ET - 18 - OCH3组在第12天血小板计数达到>50,000个细胞/微升，其他两组在第14天达到该水平。此外，12例转移性疾病患者在HD治疗后用阳性/阴性选择的干细胞进行救援，也显示出快速且相当的造血恢复。使用封闭系统进行的新的同时免疫磁珠阳性/阴性选择是有效且安全的。处理LP可导致相似的CD34 +细胞产量，与标准CD34 +细胞选择相比，TC清除率更高，且造血恢复没有延迟。
