Department of Molecular Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
Proc Natl Acad Sci U S A. 2012 Sep 25;109(39):15728-33. doi: 10.1073/pnas.1214275109. Epub 2012 Sep 10.
A method is presented that uses combinatorial antibody libraries to endow cells with new binding energy landscapes for the purpose of regulating their phenotypes. Antibodies that are expressed in cells infected with a lentiviral combinatorial antibody library are selected directly for function rather than only for binding. The potential diversity space can be very large because more than one lentivirus can infect a single cell. Thus, the initial combinatorial diversity of ~1.0 × 10(11) members generated by the random association of antibody heavy and light chains is greatly increased by the reassortment of the antibody Fv domains themselves inside cells. The power of the system is illustrated by its ability to select unusual antibodies. Here, the selected antibodies are potent erythropoietin agonists whose ontogeny depends on recombination at the protein level of pairs of antibodies expressed in the same cell to generate heterodimeric bispecific antibodies. The obligate synergy between the different binding specificities of the antibody's monomeric subunits appears to replicate the asymmetric binding mechanism of authentic erythropoietin.
本文提出了一种利用组合抗体文库赋予细胞新的结合能量景观的方法，目的是调节其表型。通过感染慢病毒组合抗体文库的细胞表达的抗体，直接针对功能而不是仅针对结合进行选择。潜在的多样性空间可以非常大，因为一种以上的慢病毒可以感染单个细胞。因此，通过细胞内抗体 Fv 结构域自身的重排，通过抗体重链和轻链的随机组合产生的初始组合多样性~1.0×10^11 个成员大大增加。该系统的强大功能体现在其选择不寻常抗体的能力上。在这里，选择的抗体是有效的促红细胞生成素激动剂，其发生取决于在同一细胞中表达的成对抗体在蛋白质水平上的重组，以产生异二聚体双特异性抗体。抗体单体亚基的不同结合特异性之间的强制性协同作用似乎复制了天然促红细胞生成素的不对称结合机制。
