Scientists have access to several approaches for developing cell lines. A researcher can choose between the traditional methods that have been in use for decades and powerful new technologies for creating cell lines through genome editing. Each method has at one time or another been preferred for its particular strength or advantage; while some tried and true methods have fallen by the wayside with the adoption of newer technologies, many older protocols are still in use alongside next-generation methods.
Traditional cell line development approaches
Most cell biologists are familiar with the non-genome-editing approaches used to develop cell lines – single cell cloning, overexpressing genes or transgenes, cell line adaptation through media changes, and stem cell differentiation. Each method has its advantages and disadvantages.
Single cell cloning incubates cells individually and looks for potentially useful variations. This cloning method is straightforward but takes a long time and has limited impact. Similarly, cell line adaptation gradually changes the conditions in which the cells are grown, such as media or cell density; this method is also uncomplicated but time consuming. By contrast, gene/transgene overexpression inserts foreign DNA into cells. While this method produces quicker results, the new genetic material is difficult to control because the transcription of the exogenous gene is always on.
An alternative to cloning methods is differentiating stem cells. Versatile cell types such as mesenchymal stem cells and induced pluripotent stem cells can be differentiated to create unique cells that might otherwise be difficult to isolate and produce