Scientists have been able to culture microorganisms since the late 1870s. On the contrary, the cultivation of human cells was not possible until 1951, after the discovery of the “immortal” HeLa cells. These cells come from the uterus of a 31-year-old African American woman who was diagnosed with cervical cancer. Her name was Henrietta Lacks, after whom these HeLa cells were named. Sadly, Lacks died soon after her diagnosis, but her cells were kept alive in many laboratories around the world. A biopsy from Lacks’ tumor was taken during her stay at the Johns Hopkins Hospital, and samples were then passed along to George Otto Gey’s research laboratory, without her knowledge or permission (1). 

By 1951, researchers like Gey were still trying to grow human cells without success. Due to the normal lifespan of cells, they were only capable of cultivating them for a couple of days. However, the cells obtained from Lack’s cervical cancer were different. They replicated twenty times faster than Lacks’s non-cancerous cells and continued to sustain themselves in the laboratory. Gey informed his colleagues that his group may have grown the first immortal human cell line, and he offered them vials of HeLa cells to use for their research experiments. 70 years after the discovery of Lacks’ cancerous cells, they taught us how diseases worked: cancer, polio, human papillomavirus and many more. Within these discoveries, synthetic biology has played an important role. And just as important as these experiments, Lacks’ story opened the debate on the importance of counting with patients’ consent for research with their samples. Nowadays, what type of studies are being done with HeLa cells in the field of SynBio? And, why are they affected by informed consent? 

A lasting contribution to biomedicine

After their discovery, HeLa cells became a very popular in vitro model for scientists interested in biomedical research. Nowadays, a quick search of the term “HeLa cells” in Pubmed shows more than 115,000 scientific publications regarding cancer, nanotechnology, virology, etc. This website from the National Institute of Health (NIH) contains a world map indicating the number of studies published using the HeLa cell line per country and an infographic showing the vast spectrum of topics in which these cells have been used. 

Lacks’ legacy has also impacted the field of synthetic biology. HeLa cells have been used for a wide range of experiments to study their genome and to identify gene interactions and transcriptional regulation factors. This has been possible thanks to the development of synthetic biology techniques such as RNA interference and CRISPR. For instance, researchers have been able to develop a HeLa cancer cell classifier that selectively identifies these cells and triggers apoptosis without affecting non-HeLa cell types. All of this with a transcriptional circuit that senses expression levels of endogenous miRNAs (2).

On the other hand, HeLa cellular models have also been used to study the SARS-CoV-2 infection, using a genome-wide CRISPR-Cas9 knock-out system in HeLa cells overexpressing entry receptor angiotensin-converting enzyme 2 (ACE2). This study has allowed researchers to identify factors that may serve as potential therapeutic targets, such as ACE2 or EPGN genes (3). These are just two examples of how the HeLa cell line has been involved in the field of synthetic biology, but Henrietta Lacks’ legacy goes beyond the lab. 

An open debate on informed consent  

After Gey and his colleagues started using the HeLa cell line, word got around that these cells would be the key to understanding and conquering cancer. With time HeLa cells became the instrument that was increasing the pharmaceutical industry profits. Meanwhile, Lacks’ family had lived in poverty for most of their lives and had no idea that the cells from her ancestor were revolutionizing biomedical research. It wasn’t until 1973 when scientists asked Lacks’ family for DNA samples when they found out. This led the family to launch a campaign to get the money they felt they owned (1). 

Then, Lacks’ story became a public concern. It opened the debate on informed consent, especially after 2013 when the NIH published the whole genome sequence of HeLa cells. By that time, this was legal, but it provided private information about Lacks and her descendants to millions of people. The researchers removed the sequence from the public domain until an agreement was reached with Lacks’ family (4).

Ever since then, many experiments performed in human samples require the informed consent to be signed by the patient to exactly know the purpose of using their cells. This has become especially important in the field of synthetic biology and genome editing experiments. As these types of experiments are becoming more common, it is important for scientists to build models of consent that increase patients’ trust and understanding on the use of their samples (5). 

HeLa cells have been involved in many other ground-breaking advances in science, and there’s no doubt that these cells will be key players in the future of biomedical research within synthetic biology. However, Henrietta Lacks story has taught us the importance of counting with patients’ acceptance when using their samples. Only with society’s trust in researchers will scientific knowledge fullfil its role in public wellbeing.

 

References 

  1. Lucey, B. P., Nelson-Rees, W. A., & Hutchins, G. M. (2009). Henrietta Lacks, HeLa Cells, and Cell Culture Contamination. Archives of Pathology & Laboratory Medicine, 133(9), 1463–1467. https://doi.org/10.5858/133.9.1463
  2. Xie, Z., Wroblewska, L., Prochazka, L., Weiss, R., & Benenson, Y. (2011). Multi-input RNAi-based logic circuit for identification of specific cancer cells. Science (New York, N.Y.), 333(6047), 1307–1311. https://doi.org/10.1126/science.1205527
  3. Synowiec, A., Jedrysik, M., Branicki, W., Klajmon, A., Lei, J., Owczarek, K., Suo, C., Szczepanski, A., Wang, J., Zhang, P., Labaj, P. P., & Pyrc, K. (2021). Identification of Cellular Factors Required for SARS-CoV-2 Replication. Cells, 10(11), 3159. https://doi.org/10.3390/cells10113159
  4. Beskow, L. M. (2016). Lessons from HeLa Cells: The Ethics and Policy of Biospecimens. Annual Review of Genomics and Human Genetics, 17, 395–417. https://doi.org/10.1146/annurev-genom-083115-022536
  5. Ganguly, P. (2020). As genome-editing trials become more common, informed consent is changing. Retrieved from https://www.genome.gov/news/news-release/As-genome-editing-trials-become-more-common-informed-consent-is-changing