WI-38
WI-38 is a diploid human cell strain composed of fibroblasts derived from lung tissue of a 3-months gestation female fetus. The cell strain, isolated by Leonard Hayflick in the 1960s, has been used extensively in scientific research, with applications ranging from developing important theories in molecular biology and aging to the production of most human virus vaccines. The contributions from this cell strain towards human virus vaccine production have been credited with avoiding disease in, or saving the lives of, billions of people.