Neurauter Axl A, Bonyhadi Mark, Lien Eli, Nøkleby Lars, Ruud Erik, Camacho Stephanie, Aarvak Tanja
Invitrogen Dynal AS, Oslo, Norway.
Adv Biochem Eng Biotechnol. 2007;106:41-73. doi: 10.1007/10_2007_072.
This chapter describes the use of Dynabeads for cell isolation and expansion. Dynabeads are uniform polystyrene spherical beads that have been made magnetisable and superparamagnetic, meaning they are only magnetic in a magnetic field. Due to this property, the beads can easily be resuspended when the magnetic field is removed. The invention of Dynabeads made, by Professor John Ugelstad, has revolutionized the separation of many biological materials. For example, the attachment of target-specific antibodies to the surface of the beads allows capture and isolation of intact cells directly from a complex suspension such as blood. This is all accomplished under the influence of a simple magnetic field without the need for column separation techniques or centrifugation. In general, magnetic beads coated with specific antibodies can be used either for isolation or depletion of various cell types. Positive or negative cell isolation can be performed depending on the nature of the starting sample, the cell surface markers and the downstream application in question. Positive cell isolation is the method of choice for unprocessed samples, such as whole blood, and for downstream molecular applications. Positive cell isolation can also be used for any downstream application after detachment and removal of the beads. Negative cell isolation is the method of choice when it is critical that cells of interest remain untouched, i.e., no antibodies have been bound to any cell surface markers on the cells of interest. Some cell populations can only be defined by multiple cell surface markers. Such populations of cells can be isolated by the combination of negative and positive cell isolation. By coupling Dynabeads with antibodies directed against cell surface activation molecules, the beads can be used both for isolation and expansion of the cells. Dynabeads are currently used in two major clinical applications: 1) In the Isolex 300i Magnetic Cell Selection System for CD34 Stem Cell Isolation--2) For ex vivo T cell isolation and expansion using Dynabeads ClinExVivo CD3/CD28 for clinical trials in novel adoptive immunotherapy.
本章介绍了Dynabeads在细胞分离和扩增中的应用。Dynabeads是均匀的聚苯乙烯球形磁珠，具有可磁化和超顺磁性，这意味着它们仅在磁场中具有磁性。由于这一特性，当移除磁场时，磁珠可以很容易地重新悬浮。由约翰·于格斯塔德教授发明的Dynabeads彻底改变了许多生物材料的分离方式。例如，将靶向特异性抗体附着在磁珠表面，可以直接从诸如血液等复杂悬液中捕获和分离完整细胞。这一切都在简单磁场的影响下完成，无需柱分离技术或离心。一般来说，包被有特异性抗体的磁珠可用于各种细胞类型的分离或去除。根据起始样本的性质、细胞表面标志物以及相关的下游应用，可以进行阳性或阴性细胞分离。阳性细胞分离是未处理样本（如全血）以及下游分子应用的首选方法。阳性细胞分离也可用于磁珠分离和去除后的任何下游应用。阴性细胞分离是在确保感兴趣的细胞未受影响（即没有抗体结合到感兴趣细胞的任何细胞表面标志物）至关重要时的首选方法。一些细胞群体只能通过多个细胞表面标志物来定义。这样的细胞群体可以通过阴性和阳性细胞分离相结合的方法来分离。通过将Dynabeads与针对细胞表面激活分子的抗体偶联，磁珠可用于细胞的分离和扩增。Dynabeads目前主要用于两项临床应用：1）在用于CD34干细胞分离的Isolex 300i磁性细胞分选系统中——2）在新型过继性免疫疗法的临床试验中，使用Dynabeads ClinExVivo CD3/CD28进行离体T细胞分离和扩增。
