Optimization of transfection methods for human lymphoblast TK6 cell line

Transfection has recently gained attention in the field of biomedical research due to its ability to manipulate gene expression. Every mammalian cell type has a characteristic set of requirements for optimal transfection. Some cells can be difficult to transfect and require optimization for successful transfection. Human lymphoblast TK6 cell line, an important cell line for genotoxic studies, is known to be extremely hard to transfect. Thus, optimizing transfection methods for human lymphoblast TK6 are increasingly important. To accomplish this, TK6 human lymphoblasts were transfected with plasmid constructs that expressed green fluorescent protein (GFP) and NanoLuc® activity. We compared the transfection efficiency of three commercially available transfection reagents, including Amaxa 96-well Nucleofection procedure using various solutions (SF, SE, and SG), Lipofectamine LTX, and Metafectene Pro®. The transfection efficiency and toxicity of various reagents were tested by fluorescence microscopy, luciferase activity, and cell viability assays. Amaxa 96-well Nucleofection Solution SF was identified as the best transfection reagent due to its relatively high luciferase activity, acceptable cell viability (80%), and GFP transfection efficiency (80%). Optimal conditions for transfection utilized with this reagent included 0.4 μg of plasmid DNA, 1.8 × 105 cells, and using the DS 137 Nucleofector program.