Immortal cells are almost exactly what you think they are - cells that can be grown for an unlimited amount of time, frozen for several years, and therefore are able to be shared among countless scientists. In 1951, a scientist at Johns Hopkins Hospital in Baltimore created the first strain of these cells by taking a sample from a young black woman who had cervical cancer. No one knows why, but her cells never died! These amazing cells were named "HeLa cells," after their unwitting donor, Henrietta Lacks...however, Henrietta's identity was soon lost for several decades.
25 years after Henrietta's death, a scientist realized that cells thought to be from other tissue types were actually HeLa cells! In order to sort out which cells were which, Henrietta's relatives had to be located. The researchers managed to do so, which drew attention to the immorality of the original donation, especially considering that Henrietta's cells spawned a multi-billion-dollar industry while her family was living in severe poverty.
Though the initial extraction is be frowned upon (and for good reason!), that first scientist's good intentions did manage to come to fruition in countless extremely important ways. Henrietta's cells played an integral part in developing the polio vaccine and gave birth to the field of virology as a whole! They made manned space travel a possibility by showing what would happen to human cells in space aboard one of the first Soviet satellites in space. Several other scientific breakthroughs have used her cells, including cloning, gene mapping, in vitro fertilization, and cryogenics!
Read more about this amazing story here.