Kvalheim G, Fodstad O, Pihl A, Nustad K, Pharo A, Ugelstad J, Funderud S
Cancer Res. 1987 Feb 1;47(3):846-51.
Conditions for removing B-lymphoma cells from human bone marrow using "immunobeads" (IBs) were investigated. The IBs were prepared by coupling monoclonal antibodies directly to a new type of monodisperse magnetic polymer particles (M 450). Two monoclonal immunoglobulin M antibodies, AB-1 (CD 19), a B-cell-specific antibody, and AB-4, an HLA-DR-specific antibody, were used. The IBs were incubated with Rael Burkitt lymphoma cells admixed to fresh, mononuclear human bone marrow cells. After incubation for 30 min at 4 degrees C, the IBs were removed using cobalt samarium magnets. The number of remaining clonogenic tumor cells was assayed by the Courtenay and Mills soft agar procedure, and the clonogenic capacity of the bone marrow progenitor cells was measured by granulocyte-monocyte and granulocyte-erythroid-monocyte-megakaryocyte assays. With a ratio of tumor cells to normal bone marrow cells of 0.1 or 0.01 and a ratio of immunobeads to tumor cells in excess of 75, a tumor cell depletion of more than 3 logs was achieved with the AB-4 IBs and slightly less with the AB-1 beads. After two consecutive cycles of purification with the AB-4 beads, no colonies were found, corresponding to more than 6 logs of purification. In the case of the AB-1 beads, 4 to 5 logs of purification were achieved. The concomitant reduction in clonogenic bone marrow progenitor cells was only 30 to 40%. Flow cytometric studies showed that the tumor cell population contained appreciable proportions of cells binding only small amounts of the antibodies used. The results indicate that the IB procedure is highly efficient and capable of removing tumor cells expressing low levels of antigen. Compared to other purging methods in use the procedure described seems to offer several advantages with respect to efficacy, speed, and simplicity. By the use of a panel of suitable antibodies the new immunobead procedure may be potentially useful in autologous bone marrow transplantation of B-lymphomas and non-T-leukemias with poor prognosis.
研究了使用“免疫磁珠”（IBs）从人骨髓中去除B淋巴瘤细胞的条件。通过将单克隆抗体直接偶联到新型单分散磁性聚合物颗粒（M 450）上来制备免疫磁珠。使用了两种单克隆免疫球蛋白M抗体，即B细胞特异性抗体AB - 1（CD 19）和HLA - DR特异性抗体AB - 4。将免疫磁珠与混入新鲜人单核骨髓细胞中的拉埃尔·伯基特淋巴瘤细胞一起孵育。在4℃孵育30分钟后，使用钴钐磁体去除免疫磁珠。通过考特尼和米尔斯软琼脂程序测定剩余的克隆形成肿瘤细胞数量，并通过粒细胞 - 单核细胞以及粒细胞 - 红细胞 - 单核细胞 - 巨核细胞测定法测量骨髓祖细胞的克隆形成能力。当肿瘤细胞与正常骨髓细胞的比例为0.1或0.01且免疫磁珠与肿瘤细胞的比例超过75时，使用AB - 4免疫磁珠可实现超过3个对数级的肿瘤细胞清除，使用AB - 1磁珠的清除效果略低。用AB - 4磁珠连续纯化两个循环后，未发现集落，相当于超过6个对数级的纯化。对于AB - 1磁珠，可实现4至5个对数级的纯化。同时，克隆形成的骨髓祖细胞减少仅30%至40%。流式细胞术研究表明，肿瘤细胞群体中含有相当比例的仅结合少量所用抗体的细胞。结果表明，免疫磁珠程序高效且能够去除表达低水平抗原的肿瘤细胞。与其他正在使用的净化方法相比，所述程序在功效、速度和简便性方面似乎具有几个优点。通过使用一组合适的抗体，新的免疫磁珠程序可能在预后不良的B淋巴瘤和非T白血病的自体骨髓移植中具有潜在用途。
