Immortal Cells??? Yes, They Exist!

You've heard of HeLa cells, but have you heard of Henrietta Lacks? Maybe you haven't heard of either. Have no fear- that was me just a few months ago, sitting in Government Studies being presented with a 200 page pdf titled The Immortal Life of Henrietta Lacks. Upon reading the book, written by Rebecca Skloot, I would come to find out that Henrietta Lacks's immortality was not a fairytale or myth or magic of any sort- it was a story of incredible biology that honestly blew my mind. Henrietta herself was not really immortal, her cells were--no, her cells are. 

There are two beginnings to the story of HeLa cells. One begins in 1951, when Dr. George Gey first obtained and cultured Henrietta Lacks' cells. The other begins 31 years earlier- at the start of Henrietta Lacks' life. Click here to read my VERY simplified summary of Henrietta Lacks' life--I encourage you to read The Immortal Life of Henrietta Lacks as well (very interesting read especially with our knowledge of genetics and bio!!).

A painting of Henrietta Lacks

An actual image of HeLa cells! They are tagged with fluorescence.

Let's start with the basics: HeLa cells are a line of stem cells developed at Johns Hopkins Hospital in 1951 by Dr. George Gey. The cells are often characterized as 'immortal' because of their unique ability to proliferate abnormally rapidly, allowing the cells to survive in artificial settings like Dr. Gey's lab. This characteristic provided scientists around the world with an adaptable cell line that has been instrumental in gene mapping technologies and the study of human diseases. Even as the first of its kind, the HeLa cell line is still the most populous and commonly used cell line today. For a long time, people knew that these spectacular cells were extracted from a woman with cervical cancer. What they didn't know was that HeLa cells belonged to a poor, black woman named Henrietta Lacks who had no knowledge of the medical research her cells had advanced, let alone given consent for the removal and usage of her cells at all. The ethics of Dr. Gey's work has been debated for a few decades- although Johns Hopkins Hospital itself and Dr. Gey did not profit from Henrietta's cells, their collective dispersal of the cells worldwide and creation of a market for cell lines has allowed many scientists as well as corporations to profit off of Henrietta's tissue. Do you think it's ethical to profit from the nonconsensual removal of human tissue? Me neither. So when the Lacks family learned of the injustices they had endured, they began a long fight for fiscal compensation. Because of a general lack of information/poor record keeping as well as the noncooperation of many doctors and journalists, the family had a very hard time in their legal battles. Now, the Lacks family has full authority over who can use and study Henrietta's cells, an agreement formed with Johns Hopkins that came with a collection of scholarships, symposiums, and educational programs established to honor Henrietta Lacks. Read about them + the evolution of bioethical practices here. 

Now that you know all about the person and ethics behind HeLa cells, let's delve into the biology of things! The birth of HeLa cells was an incredible breakthrough in the field of immunology. As I'm sure you've guessed from the name, immunology is a branch of biological research concerned with the immune system and immune responses. One of the first contributions HeLa cells made to immunology was in 1954, when Jonas Salk used the cell line to develop the polio vaccine. The cells' durability supplied Salk with the massive amounts of human tissue necessary for his vaccine research. The cancer cells that scientists like Salk had previously attempted to study would divide a few times outside of the body, but die off before any scientific conclusions could be reached. 

Jonas Salk with the polio vaccine.

So HeLa cells are unique from other cells in their ability to multiply infinitely, but they are just like all other cells in that they are not self sufficient. In order to keep HeLa cells alive and growing, they must be fed the right mix of nutrients in the culture medium. Today, HeLa cells are maintained in Dulbecco's modified Eagle medium (DMEM), which contains 0.11 g/liter sodium pyruvate, 2mM I-glutamine, 4.5 g/liter glucose, 10% fetal bovine serum, 100 U/ml penicillin, and 100 U/ml streptomycin. The cells and medium are kept in a humidified incubator, just like the one we used in the lab simulations. 

One of the other vital molecules HeLa cells need is ATP. The uncontrolled growth of cancer cells like HeLa cells requires the replication of all cellular components: DNA, RNA, proteins- the list goes on. This requires energy, as I'm sure we all know, so in order to compensate for the increased and constant need for energy, cancer cells adjust their metabolism accordingly. HeLa cells utilize aerobic respiration, which is a less efficient metabolic pathway than anaerobic respiration, producing less ATP per glucose molecule but at a much faster rate. Cancer cells consume 20 times more glucose than normal cells, but produce ATP almost 100 times faster!

Diagram of aerobic respiration in a normal cells compared to a cancer cell

I hope you find Henrietta Lacks' cells as fascinating as I do! I think it's super important to remember that a lot of the scientific advancements that have changed medicine and biology have come from the exploitation of vulnerable people, which Henrietta's story is an example of. We should also remember that a name can tell us so much- tertiary consumer tells us that an organism eats secondary consumers, HeLa tells us who the amazing cells came from: Henrietta Lacks!