Immortal Cells

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Henrietta Lacks lived a pretty normal life during the early 20th century but that changed in 1951 when she was diagnosed with cancer. It was suspected to be a malignant epidermal carcinoma in the cervix, but it was discovered after 20 years that this was incorrect and the cancer was actually an adenocarcinoma. But, treatment was the same for both so this wasn’t too serious of an issue.

During her treatment, doctors took a biopsy of some healthy tissue and cancerous tissue. These were given to cancer researcher and physician George Gey. When inspecting the cancerous tissue, he noticed a strange phenomenon. They were able to grow indefinitely. Although Lacks, unfortunately, died in October of 1951 due to her cancer, these cells lived on, even to this day!

These immortal cells were dubbed HeLa cells (by taking the first two letters of her first name and surname) and had great impacts on the field of medicine.

But before we delve further into its impacts, how can such a phenomenon exist? It all comes down to cell division. Cells divide by mitosis, a series of phases that allows a cell to split into two. The first step is prophase. Here, the DNA condenses into a shape somewhat similar to an X. At the very tips of the X, there is a series of repeated nucleotide sequences known as telomeres. As mentioned in a previous article, they shorten as the cell divides more and more, until they reach what’s known as the Hayflick’s limit. At this point, the telomere is too short, so the cell no longer divides and becomes senescent. But, in HeLa cells, there is a special enzyme that prevents senescence. This enzyme is known as telomerase, which is able to regenerate the telomere and thus allowing a cell to divide forever.

So now we know why they are immortal but why should we care? One of the first uses of HeLa cells came from scientist Jonas Salk. He had cleverly created a vaccine for the virus poliomyelitis, which causes the devastating disease polio. However, he needed to make sure it actually worked on humans and was safe. By mass-producing HeLa cells, Salk was able to show that it would be safe to conduct human trials and within a year, these trials occured. Thanks to this vaccine, hundreds of thousands of lives were saved, and there were only 33 new cases in 2018.

Another development accelerated through the use of HeLa cells was the HPV vaccine. Scientist Harald zur Hausen discovered that in the original biopsy of the HeLa cells, there was a new strain of HPV known as HPV-18. This strain was, in fact, the cause of Lacks’ death. By linking the HPV with cervical cancer, research on vaccines soon were underway, resulting in a vaccine. The use of HeLa cells have been very important to the field of virology. As seen in previous examples, scientists can infect these cells with the virus to learn more about its pathology and develop treatments and preventative measures. Other notable diseases being researched with HeLa cells include HIV, Zika, herpes and mumps.

Being one of the first original immortal cell lines, HeLa cells paved the way for many other immortal cell lines, which proved immensely useful for research. Our knowledge of certain drugs, treatments, viruses and cancer have grown exponentially thanks to an endless source of cells.

But, there are a few controversies and issues regarding HeLa cells. A significant issue lies in the fact that the original biopsy of Henrietta Lacks was without consent. In other words, they extracted the cancerous tissue without her permission. This certainly violates the medical-ethics pillar of Autonomy and if an similar incident occurred today, it would be highly condemned by medical societies and might possibly face legal charges. However, at the time, such actions were deemed OK.

What’s more shocking is that while these cells were being mass-produced and researched, Lacks’s family members were left completely in the dark. In 1980, Henrietta’s medical records were published without the family’s knowledge or consent. In 2013, researchers published the genome of a strain of HeLa cells, and the family were informed after it had been published. Fortunately, in late 2013, the National Institute of Health and the family members made an agreement, making sure that further testing and research was ethically sound.

In terms of the science, HeLa cells have issues that must be addressed by researchers. Due to their remarkable ability of dividing fast and continously, these cells can outcompete other cells very easily, creating a large concern for contamination. Even in today’s modern cell cultures, there is still a large risk of contamination so scientists have to be extra careful.

To conclude, HeLa cells have been very useful to modern medicine, leading to many discoveries that saved millions of lives. However, it’s very important to learn from its history and make sure these mistakes aren’t made again. Due to the mysterious and fascinating phenomenon that is life, it’s especially important in biology and medicine that research and experimentation remains ethical!


References

  1. Sinha, A., 2020. Telomeres: Nature’s Secret Weapon – Scio. [online] Scio. Available at: <https://scio.uk/medicine/telomeres-natures-secret-weapon/> [Accessed 3 July 2020].
  2. Butanis, B., n.d. The Legacy Of Henrietta Lacks. [online] Hopkinsmedicine.org. Available at: <https://www.hopkinsmedicine.org/henriettalacks/> [Accessed 3 July 2020].
  3. Immunology.org. n.d. Hela Cells (1951) | British Society For Immunology. [online] Available at: <https://www.immunology.org/hela-cells-1951> [Accessed 3 July 2020].https://www.immunology.org/hela-cells-1951
  4. Turner, T., 2012. Development of the Polio Vaccine: A Historical Perspective of Tuskegee University’s Role in Mass Production and Distribution of HeLa Cells. Journal of Health Care for the Poor and Underserved, 23(4a), pp.5-10.

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