Introduction:
Historically, scientists had attempted for many decades to create a cell line which could be multiplied indefinitely, a feat which, if achieved could revolutionise science. In spite of this, all endeavours resulted in the same futile outcome. However this was soon to change, when, in 1951, 31-year-old Henrietta Lacks visited John Hopkins for cervical cancer treatment where a surgeon took a sample of her tumour¹. Little did anyone know that this sample would grow to become the first immortal human cell line (HeLa) and contribute so much to modern medicine.
↓
Contributions to medicine: A timeline
Following the revelation that the HeLa cell line could multiply at a prolific rate and stayed alive in culture for long periods of time, their popularity grew. In fact, it is estimated that if all the HeLa cells ever grown were laid in a line, they would wrap around the Earth three times! Samples were sent across the globe for scientists to use in research, the results of which transformed treatment methods, many of which we still use today. Below is a short timeline covering a few of the many ways in which the cells revolutionised science.
↓
1953: The polio vaccine
During the development of the polio vaccine, scientists required cells which could be used to test its efficacy, and the HeLa cells were found to be more susceptible to polio infection than other cell lines. The Tuskegee institute, also the site of the infamous syphilis studies, was chosen as the location to create a factory dedicated to manufacturing the cells. Culturing of the HeLa cells occurred at a never-before-seen industrial scale, contributing to rapid subsequent clinical trials and rollout of the vaccine². Since their implementation, 2 of the 3 strains of the disease have been globally eradicated, as well as a 99% decrease in wild poliovirus cases, saving millions of lives³.
↓
1964: Treatment for blood disorders
Hydroxyurea is now a common treatment for a range of blood disorders, ranging from cancer to sickle cell anaemia and testing on the HeLa cells laid the groundwork for its approval. A group of researchers found that the drug was not only able to reduce cancerous growth rates, but also prevent ‘sickle-shaped’ red blood cells⁴. It achieves this by increasing the levels of foetal haemoglobin, making the erythrocytes larger and more flexible, alleviating symptoms of the disease⁵.
↓
1983: HPV/cervical cancer
In the 1980s, a virologist analysed the HeLa cells to find that they contained HPV-18, which caused Henrietta Lacks’ cervical cancer by switching off her tumour suppressor gene. This particular strain is considered to be one of the most dangerous, and further research enabled the development of the HPV vaccine, which is now commonly administered to teenage girls⁶.
↓
2020: Covid-19
To this day, the HeLa cells are being used in research, and they were particularly useful in studying the infectivity of the SARS-CoV-2 virus. It was found in a 2020 study that this form of the virus was unable to infect these cells as well as expected, which prompted research into the cause. It was previously known that other forms of coronavirus use a molecule called ACE2, commonly found on the surface of some body cells. Modification of the HeLa cells to produce and display the molecule enabled the virus to infect and therefore replicate inside the cells⁷. Studies such as this, among others, paved the way for the development of the vaccine, which was estimated to have saved 20 million lives in 1 year⁸.
These are just a few of the many ways in which the HeLa cells have been used in scientific research in order to further develop our understanding of disease. However over the years, the HeLa cells have been subject to controversy due to ethical concerns.
Ethical issues:
The story of Henrietta Lacks was largely unknown until it was brought to public attention by author Rebecca Skloot through her bestseller ‘The Immortal Life Of Henrietta Lacks.’ The book raised awareness about informed consent in scientific research, since when the tissue sample was taken from Lacks, there was no legal or ethical requirement for doctors to obtain permission from the patient¹. As a result, it was only 25 years after Henrietta Lacks’ death that her family found out about the cell line, at which point the cells had contributed to the polio vaccine, cancer research and even been sent to space!
Since the 1950s, the situation with informed consent has vastly improved, with much tighter regulation on a patient’s rights. Yet, this leads one to think of what would have happened if informed consent had been required at the time. If Henrietta had the choice and declined scientists taking a sample, would we be living in a very different world? Would some of the advancements that we take for granted today not exist? The tradeoff between ethics and public benefit remains controversial, but further awareness enables better decisions to be made.
Additionally, there stands the question as to who should benefit financially from the cells. Whilst large pharmaceutical companies profited off of the research on HeLa cells, the Lacks family remained in poverty, unable to afford proper health coverage and support themselves. Whether the family should profit from the cells remains controversial, however in 2013 a stride was made by the NIH (the National Institute of Health), which meant that two members of the Lacks family are now involved in deciding who is permitted to use the HeLa cells⁹.
Conclusion:
Overall, the HeLa cell line has played a major developmental role for modern medicine, aiding us in curing and alleviating a range of diseases. Whether it be helping to eradicate polio or treat blood disorders, there is no doubt that many lives have been saved. However, this does not mean that the ethical issues should be overlooked, and although informed consent has come a long way since the 1950s, we still face several challenges. Notably, in developing countries there have been cases of violation of consent, often with regard to misinforming patients of potential dangers associated with procedures and trials. As we look into the future, we need to aim for a balance between obtaining tissues ethically, but still having a supply large enough to conduct meaningful research. Whether this can be achieved remains unknown, but at least we are taking strides in the right direction.
Nyneisha Bansal, Youth Medical Journal 2023
References:
1. Skloot R. The immortal life of Henrietta Lacks. New York: Crown Publishers; 2010.
2. Turner T. 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. 2012;23(4a):5-10.
3. Poliomyelitis (polio) [Internet]. Who.int. [cited 24 August 2022]. Available from: https://www.who.int/health-topics/poliomyelitis#tab=tab_1
4. Significant Research Advances Enabled by HeLa Cells [Internet]. Office of Science Policy. [cited 24 August 2022]. Available from: https://osp.od.nih.gov/scientific-sharing/hela-cells-timeline/
5. [Internet]. Hematology.org. [cited 24 August 2022]. Available from: https://www.hematology.org/-/media/Hematology/Files/Education/Hydroxyurea-Booklet.pdf
6. Samuel L. 5 important ways Henrietta Lacks changed medical science [Internet]. STAT. 2017 [cited 24 August 2022]. Available from: https://www.statnews.com/2017/04/14/henrietta-lacks-hela-cells-science/
7. Jackson N. Vessels for Collective Progress: the use of HeLa cells in COVID-19 research – Science in the News [Internet]. Science in the News. 2020 [cited 24 August 2022]. Available from: https://sitn.hms.harvard.edu/flash/2020/vessels-for-collective-progress-the-use-of-hela-cells-in-covid-19-research/
8. COVID-19 vaccines saved an estimated 20 million lives in 1 year [Internet]. CIDRAP. 2022 [cited 24 August 2022]. Available from: https://www.cidrap.umn.edu/news-perspective/2022/06/covid-19-vaccines-saved-estimated-20-million-lives-1-year
9. Frequently Asked Questions | Johns Hopkins Medicine [Internet]. Hopkinsmedicine.org. [cited 26 August 2022]. Available from: https://www.hopkinsmedicine.org/henriettalacks/frequently-asked-questions.html#:~:text=How%20is%20consent%20different%20today,Federal%20law%20requires%20informed%20consent.
Youth Medical Journal 