Normal HEK (Human Embryonic Kidney) cells refer to the primary cells that are directly isolated from human embryonic kidney tissue. These cells are not immortalized, meaning they have a limited lifespan in culture and will eventually stop dividing due to cellular senescence. Normal HEK cells typically maintain many of their original characteristics, including morphology, gene expression, and function.
However, when most researchers refer to HEK cells, they are usually referring to the widely-used HEK293 cell line, which is an immortalized cell line derived from human embryonic kidney cells. HEK293 cells were transformed with a small piece of DNA from the adenovirus genome, allowing them to grow indefinitely in culture. These cells have been extensively used in research due to their high transfection efficiency, rapid growth, and ability to adapt well to various culture conditions.
While normal HEK cells can provide a more physiologically relevant model for studying kidney function and cellular processes, they can be more challenging to maintain in culture and have a limited lifespan compared to the HEK293 cell line. In contrast, HEK293 cells offer several advantages for research, such as ease of handling and reproducibility, but they may not accurately represent the physiological context of normal kidney cells due to their immortalized nature and genetic modifications.