Henrietta Lacks was integral to the formulation of the polio vaccine, cloning, mapping genes, biomedical ethics, the field of virology, and many other facets of modern medicine. But, she never looked down a microscope. She never invented anything. She never authored a scientific paper. She was not a scientist of any kind. Why is she featured on this website? In 1951, before she lost her fight with cervical cancer, samples were taken from her body, and that cell line is still alive today.

Traditionally, human cells had been difficult to culture. They died after a few short days, prohibiting long term experiments. However, when Dr. George Gey of Johns Hopkins University collected cells from Henrietta Lacks (and abbreviated the tube as HeLa), a lineage of cancer cells was discovered that had incredible resilience. The cells grew so quickly and readily, they were able to be distributed to scientists around the world for experimentation free of charge -- without Henrietta’s knowledge or consent. At the time, bioethical standards were starting to come together. While informed consent may have been recommended, it was not required. The samples which had an abnormal longevity were eventually sent to laboratories around the world without the knowledge or consent of Henrietta or her family.

Why are these cells considered “immortal”? When DNA replicates, the telomeres at the end of chromosomes shorten with every round. After about 50 divisions, typical human cells reach what is known as the Hayflick Limit, where the telomeres have become too short to divide, and the cell undergoes apoptosis. Cancer cells do not respond in the same way. This, combined with the natural strength of Henrietta’s cells, has resulted in a cell lineage that has remained hardy throughout the years.

As of today, Henrietta’s cells have lived outside her body for over 60 years; twice as long as they lived inside her body. There are now other long lasting human cell lineages studied by scientists, but HeLa cells were the first, and continue to be the most popular.

As genomic sequencing has become more commonplace, questions about the Lacks family’s privacy have come to the forefront. Earlier this year, papers published HeLa’s genome without first getting authorization from the family. After months of negotiations, it was announced last month that research dealing with the sequence can continue. The only caveat is that the work has to promote the greater good for humanity and researchers must do whatever they can to ensure the Lacks’ privacy.