What if you could live forever? Immortality has been sought after by countless rulers throughout history, but all were unsuccessful in locating the Fountain of Youth. Today, most believe that death will never be conquered by humanity. However, depending on your definition, someone may have already achieved immortality recently, just in the 20th century. This woman was (is?) Henrietta Lacks.
Henrietta Lacks, born in 1920, was an African American farmer, wife, and mother from rural Virginia (Collins, 2013). On January 29, 1951, Lacks visited the John Hopkins Medical Hospital, the only hospital near her residence that admitted black patients. She had suffered a severe hemorrhage after giving birth to her second child. After conducting tests, Dr. Howard Jones diagnosed her with cervical cancer. Though she received radiotherapy, the cancer metastasized throughout her body, and Lacks died just six months after her diagnosis. Yet her legacy would prove to survive much longer than her body.
During the course of her treatment, samples had been taken from Lacks’ tumor by Dr. Jones without her knowledge or permission (Skloot, 2010). These cancerous samples were then transferred to another doctor at John Hopkins, Dr. George Gey. Dr. Gey had been attempting to grow human cells in culture without success for decades. Yet, in his laboratory, Lacks’ cells never died: they more than doubled in number every 24 hours. The exact reason her cells thrived where countless other samples died out is still a mystery, but it is most likely because of a chance mutation caused by the cancer (Collins, 2013).
The HeLa cell line was the very first human cell line to proliferate in vitro (in a lab culture). The following advent of “immortal cell lines” was critical to numerous medical breakthroughs. Dr. Gey donated these cells to any inquiring scientist at no cost, confident that they would lead to great scientific discoveries. And he was not mistaken. HeLa cells were used by Dr. Jonas Salk to test one of the first polio vaccines in 1953 (Lucey et al., 2009). They helped to develop modern techniques of counting chromosomes, and revealed the 23 pairs of human chromosomes. They have been instrumental to two Nobel-prize-winning studies, which studied a possible Human Papillomavirus vaccine, and methods for preventing chromosome degradation (Landry et al., 2013). Tens of thousands of studies have used HeLa cells in some way to study the effects of vaccines, the environment, and experimental drugs on human tissue. Recently, studies have also used HeLa cells to examine the SARS-CoV-2 virus, determining how the coronaviruses can identify and infiltrate respiratory cells (Ou et al, 2020).
Although many other immortal cell lines have now been created since 1951, HeLa cells remain the most widely used. The reason for this is threefold. Firstly, since HeLa cells have been around for so long, they have become uniquely “accustomed” to culture conditions, and thrive in the lab (Rahbari et al., 2018). Secondly, they lack the contact inhibition of other cells that keep most cell cultures to one layer thick (Rahbari et al., 2018). Lastly, HeLa’s cell population can double within just one day (quicker than other cell lines), great for rapid manufacturing and distribution to scientists. HeLa cells are able to overcome the normal limits of cell division in part because they produce a high quantity of telomerase, an enzyme that builds up telomeres on the ends of chromosomes (Ivanković et al., 2006). These non-expressive telomeres act as buffer zones for the inner genes of chromosomes, which are important for keeping the cell alive and reproducing (Bernandes de Jesus & Blasco, 2013). Thus, by continually producing telomerase at a rapid pace, Hela cells’ chromosomes are protected from deterioration, and can divide almost continuously.
Unfortunately, HeLa cells have caused great scientific frustration as well as enlightenment. Because of their overwhelming resilience, HeLa cells are notorious for contaminating other cell cultures in the laboratory (Lucey et al., 2009). If even a few HeLa cells find their way into a culture, they can outcompete the other cells for nutrients and space, and eventually take over the entire complex. In fact, it has been estimated that 10-20% of all cell lines have been contaminated by HeLa cells (Lucey et al., 2009). This contamination leads to flawed science and invalid results, as data derived from cell cultures may actually be characteristics of another species of cell entirely, instead of the one intended for study.
The HeLa line’s dark side extends beyond scrupulous studies, however. Many have criticized the treatment of Lacks and her family in light of the scientific conquest propagating from her cells. Firstly, Ms. Lacks was never informed that Dr. Jones was taking her tissue samples, much less sending them to his colleague for analysis and culture (Skloot, 2010). While this lack of transparency was the norm in the 1950s, it does not make up for the blatant violation of Lacks’s rights. On the bright side, the controversy surrounding HeLa cells helped establish the medical “Common Rule” in 1991. This law requires doctors to gain patients’ informed consent before using any of their details in research, including personal information or tissue samples (Department of HHS, 2020). Furthermore, even as her cells revolutionized research, the Lacks family held no knowledge of how the deceased’s tissue was being used. Therefore, they couldn’t regulate the use of her cell line, and weren’t compensated by the researchers. In fact, the family continued to live in relative poverty for years (Skloot, 2010).
More recently, Lacks’s family has borne another injustice. In 2013, German geneticists sequenced the complete genome of the HeLa cell line. Interestingly, the researchers found that the cells contain at least one extra copy of most chromosomes, with some chromosomes’ genes shuffled like a deck of cards (Landry et al., 2013). Looking at the protein expression related to this genome, they concluded that several crucial pathways, including ones controlling cell cycle regulation and DNA repair, are expressed wildly differently within HeLa cells. This study serves as a great guide to scientists using HeLa cells in their own studies. However, once again, a severe lack of respect was shown for Lacks and her descendents: they were not consulted before the data was published, and the released genome alarmingly reveals personal genetic traits still carried by the Lacks family (Collins, 2013). The lead researcher responsible for the genomic sequencing, Lars Steinmetz, has expressed regret for his hasty actions, lamenting: “We wanted to respect the wishes of the family, and we didn’t intend to cause them any anxiety by the publication of our research” (Callaway, 2013). Following discussions between the researchers, the Lacks family, and the National Institute of Health (NIH), an agreement was reached. NIH-supported researchers would publish any DNA sequences derived from HeLa cells into a private NIH database. Other researchers could request access to this crucial data by petitioning a handpicked group of scientists, bioethicists, and Lacks family members (Collins, 2013). With this, and researchers being required to credit the Lacks contribution to relevant studies, the Lacks family agreed to allow the HeLa genome to be published within the NIH, where it is available to select researchers today.
The creation of HeLa cells sent waves through the scientific community. It is remarkably difficult to grow human cells in a lab, as genotypical cells die close to immediately once removed from the body. Immortal HeLa cells allowed scientists to break this barrier of cell reproduction. After Lacks’s biopsy in 1951, cells derived from that single tissue sample have lent themselves to more than 80,000 studies of all kinds, investigating the growth, differentiation, duplication, and deaths of cells (Landry et al., 2013). Besides acting as an indispensable tool for geneticists, HeLa cells also serve to restrain us from disregarding ethics in the pursuit of science. Millions of people will benefit from research using HeLa cells; however we must take care not to forget the one woman that made it all possible: Ms. Henrietta Lacks herself.
References
Bernardes de Jesus, B., & Blasco, M. A. (2013). Telomerase at the intersection of cancer and aging. Trends in genetics : TIG, 29(9), 513–520. https://doi.org/10.1016/j.tig.2013.06.007
Callaway, E. (2013). HeLa publication brews bioethical storm. Nature, https://www.nature.com/news/hela-publication-brews-bioethical-storm-1.12689
Collins, F. (2013). HeLa Cells: A New Chapter in an Enduring Story. NIH Director’s Blog, https://directorsblog.nih.gov/2013/08/07/hela-cells-a-new-chapter-in-an-enduring-story/
Department of Health and Human Services (HHS). Federal Policy for the Protection of Human Subjects ('Common Rule'). hhs.gov, https://www.hhs.gov/ohrp/regulations-and-policy/regulations/common-rule/index.html
Ivanković M., Ćukušić, A., Gotić, I., Škrobot, N., Matijašić, M., Polančec, D., & Rubelj I. (2006). Telomerase activity in HeLa cervical carcinoma cell line proliferation. Biogerontology, 8, 163–172(2007). https://doi.org/10.1007/s10522-006-9043-9
Landry, J. J., Pyl, P. T., Rausch, T., Zichner, T., Tekkedil, M. M., Stütz, A. M., Jauch, A., Aiyar, R. S., Pau, G., Delhomme, N., Gagneur, J., Korbel, J. O., Huber, W., & Steinmetz, L. M. (2013). The genomic and transcriptomic landscape of a HeLa cell line. G3 (Bethesda, Md.), 3(8), 1213–1224. https://doi.org/10.1534/g3.113.005777
Lucey, B. P., Nelson-Rees, W. A., & Hutchins, G. M. (2009). Henrietta Lacks, HeLa Cells, and Cell Culture Contamination. Arch Pathol Lab Med, 133(9), 1463–1467. https://doi.org/10.1043/1543-2165-133.9.1463
Ou, X., Liu, Y., Lei, X. et al. Characterization of spike glycoprotein of SARS-CoV-2 on virus entry and its immune cross-reactivity with SARS-CoV. Nat Commun 11, 1620 (2020). https://doi.org/10.1038/s41467-020-15562-9
Rahbari, R., Sheahan, T., Modes, V., Collier, P., Macfarlane, C., & Badge, R. M. (2009). A novel L1 retrotransposon marker for HeLa cell line identification. BioTechniques, 46(4), 277–284. https://doi.org/10.2144/000113089
Skloot, Rebecca (2010). The Immortal Life of Henrietta Lacks. New York: Crown/Random House, ISBN 978-1-4000-5217-2
Written by Alex Borengasser
Edited by Devanandh Murugesan
Graphics by Tiya Shah
Group advised by Lakshmi Sriram
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