Fig. 2: Schematic of ex vivo and in vivo strategies (shown in blue boxes) for treating genetic diseases.

For ex vivo approaches (left panel), autologous cells can be isolated directly from the patient and genetically modified to elicit a therapeutic effect, while allogeneic cells can be produced and readily available “off the shelf.” In vivo strategies require targeting of specific cells in order to overexpress a therapeutic gene or correct pathological mechanisms to allow functional gene expression (dashed arrows).