Human embryonic kidney 293 (abbreviated HEK 293 or HEK cells) are a cell line that was originally cultured from the kidney cells of a human embryo that had been placed in tissue culture. These cells were transformed with sheared adenovirus DNA in a laboratory in Leiden, the Netherlands. Later research showed that the transformation was effected by a 4.3 kilobase insert from the viral genome, which was incorporated into human chromosome 19. In addition, later work on HEK 293 cells has indicated that they are most similar to immature neurons, rather than typical kidney cells, and thus they are not a good in vitro model for kidney cells or kidney function. HEK 293 cells have a modal chromosome number of 64, and a complex karyotype, with two or more copies of each chromosome, including three copies of the X chromosome.
HEK293 Transfection Particulars:
HEK293 cells are easy to grow in culture and transfection kits are commercially available. Thus, HEK293 is an excellent cell line to use in transfection experiments, or to produce recombinant DNA or gene products. This has made them a popular research tool in cell biology studies, and an ideal cell line for therapeutic protein and virus production by the biotechnology industry. However, because the cells were not properly characterized before their transformation with adenovirus 5, it is not known whether they are a fibroblastic, endothelial, epithelial, or some other type of cell. For this reason, HEK293 cannot be used as an in vitro model for kidney cell studies. And, because they are an experimentally transformed cell line, they cannot be used as an in vitro model for normal cells.
A particularly transfectable variant of HK293 contains the SV40 large T-antigen, which allows for substantial replication of transfected plasmids containing the SV40 promoter by the T-antigen. Chinese Hamster Ovary Cells (CHO Cells) is another cell lines with genomes coding for the T-antigen, among others.
Transfection experiments using HEK or similar cells include adenoviral vector propagation studies, studies on the effects of drugs on cellular channels, RNAi studies, protein and protein interaction studies, and in vitro cell signaling studies. 293 and 293 T can also be used to produce lentiviral and retroviral vectors.
- Transport of norepinephrine (NE+) by transport molecules: This study used HEK 293 cells stably transfected with a gene for a human NE+ transport molecule. A series of studies were then conduceted on the cells using voltage-clamp methodology to track the sodium currents in the transfected cells, and their dependency on NE+ in the presence of cocaine and antidepressant molecules. [LINK]
- Evaluation of genomic changes in HEK 293: To improve understanding of recombinant protein production in HEK 293, this study compared stable transfected HEK 293 cells and untransfected HEK 293 cells on a genomic basis. Downregulation was observed in broad cellular function genes, possibly to free resources for recombinant protein production. In addition, an increased amount of genes associated with stress in the endoplasmic reticulum indicated some effect on protein folding and assembly. [LINK]