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Once there was a woman whose cells were immortal. What does this mean? Today, these cells have multiplied in laboratories worldwide to the point that, if you were to weigh all the cells that currently exist, they’d weigh about 50 million metric tons—about as much as 100 Empire State Buildings. So who was this woman, and why are scientists keeping her cells supplied with fresh nutrients so they can live on?

The woman was Henrietta Lacks, and her immortal cells—dubbed "HeLa"—have been essential in many of the great scientific discoveries of our time: curing polio; gene mapping; learning how cells work; developing drugs to treat cancer, herpes, leukemia, influenza, hemophilia, Parkinson’s disease, AIDS … and the list goes on and on (and on). If it deals with the human body and has been studied by scientists, odds are those scientists needed and used Lacks' cells somewhere along the way. HeLa cells were even sent up to space on an unmanned satellite to determine whether or not human tissue could survive in zero gravity.



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Lacks was an impoverished black woman who died on October 4, 1951 of cervical cancer at just 31 years old. During her cancer treatment, a doctor at Johns Hopkins took a sample of her tumor without her knowledge or consent and sent it over to a colleague of his, Dr. George Gey, who had been trying for 20 years, unsuccessfully, to grow human tissues from cultures. A lab assistant there, Mary Kubicek, discovered that Henrietta’s cells, unlike normal human cells, could live and replicate outside the body.

Go to just about any cell culture lab in the world and you’ll find billions of HeLa cells stored there. In contrast to normal human cells, which will die after a few replications, Lacks' cells can live and replicate just fine outside of the human body (which is also unique among humans). Give her cells the nutrients they need to survive, and they will apparently live and replicate along forever, almost 60 years and counting since the first culture was taken. They can be frozen for literally decades and, when thawed, they'll go right on replicating.

Before her cells were discovered and widely cultured, it was nearly impossible for scientists to reliably experiment on human cells and get meaningful results. Cell cultures that scientists were studying would weaken and die very quickly outside the human body. Lacks' cells gave scientists, for the first time, a “standard” that they could use to test things on. HeLa cells can survive being shipped in the mail just fine, so scientists across the globe can use the same standard to test against.

Lacks died of uremic poisoning, in the segregated hospital ward for blacks, about 8 months after being diagnosed with cervical cancer, never knowing that her cells would become one of the most vital tools in modern medicine and would spawn a multi-billion dollar industry. She was survived by her husband and five children; the family lived in poverty for most of their lives, and didn't find out about the fate of Lacks' incredible cells until years later.

If you'd like to know more about Henrietta Lacks and her immortal cells, check out The Immortal Life of Henrietta Lacks by Rebecca Skloot.