Machy P, Lewis F, McMillan L, Jonak Z L
Department of Cell Biology, Smith Kline & French Laboratories, King of Prussia, PA 19406-2799.
Proc Natl Acad Sci U S A. 1988 Nov;85(21):8027-31. doi: 10.1073/pnas.85.21.8027.
Large unilamellar liposomes, coated with protein A and encapsulating the gene that confers resistance to mycophenolic acid, were used as a model system to demonstrate gene transfer into specific lymphoid cells. Protein A, which selectively recognizes mouse IgG2a antibodies, was coupled to liposomes to target them specifically to defined cell types coated with IgG2a antibody. Protein A-coated liposomes bound human B lymphoblastoid cells preincubated with a mouse IgG2a anti-HLA monoclonal antibody but failed to adhere to cells challenged with an irrelevant (anti-H-2) antibody of the same isotype or to cells incubated in the absence of antibody. Transfection of target cells bound to protein A-coated liposomes was achieved by electroporation. This step was essential since only electroporated cells survived in a selective medium containing mycophenolic acid. Transfection efficiency with electroporation and targeted liposomes was as efficient as conventional procedures that used unencapsulated plasmids free in solution but, in the latter case, cell selectivity is not possible. This technique provides a methodology for introducing defined biological macromolecules into specific cell types.
用包被有蛋白A并包裹赋予对霉酚酸抗性基因的大单层脂质体作为模型系统，来证明基因向特定淋巴细胞的转移。能选择性识别小鼠IgG2a抗体的蛋白A与脂质体偶联，使其特异性靶向包被有IgG2a抗体的特定细胞类型。包被有蛋白A的脂质体与预先用小鼠IgG2a抗人 HLA 单克隆抗体孵育的人B淋巴母细胞结合，但不与用相同同种型的无关（抗H-2）抗体攻击的细胞或在无抗体情况下孵育的细胞黏附。通过电穿孔实现与包被有蛋白A的脂质体结合的靶细胞的转染。这一步至关重要，因为只有经电穿孔的细胞能在含有霉酚酸的选择性培养基中存活。电穿孔和靶向脂质体的转染效率与使用溶液中游离的未包封质粒的传统方法一样高，但在后一种情况下，无法实现细胞选择性。该技术提供了一种将特定生物大分子引入特定细胞类型的方法。
