"The original cells were transformed and immortalized in January 1973 by a young Canadian postdoc by the name of Frank Graham, who was working at the time in Leiden, the Netherlands in the laboratory of Professor Alex van der Eb. Normally, a cell has a finite number of divisions, but Graham managed to modify these cells so that they divide ad infinitum. This was his 293rd experiment, hence the name of the line (HEK stands for "human embryonic kidney cells"). "Use of fetal tissue was not uncommon in that period," Graham, a professor emeritus at Canada's McMaster University who now lives in Italy, told AFP. "Abortion was illegal in the Netherlands until 1984 except to save the life of the mother. Consequently I have always assumed that the HEK cells used by the Leiden lab must have derived from a therapeutic abortion." Vaccine developers like HEK293 because the cells are malleable and transformable into virus mini-factories. To grow viruses, you always need a host cell. It can be a chicken egg, but human cells are preferable in human medicine."