HeLa cells are the first cell line to be immortal, also used in many scientific studies. The cells are derived from the cervical cancer samples named after Henrietta Lacks, who died of cancer in 1951. These cells were taken without her and her family’s knowledge and also duplicated. They were used in many types of research. The ethical aspects of this issue became a subject of discussion by people1,2.

Normal cells and Hela cells separate each other depending on their differences:
HeLa cells behave like cancerous cells. Like many tumours, they include error-filled genomes. For instance, a normal cell contains 46 chromosomes and HeLa cells contain 76 to 80 chromosomes. Some of them are heavily mutated. Human Papillomavirus (HPV), causes cervical cancer. Its cells bind to the p53 cell, which prevents and inhibits mutations. After that chromosome mutations occur and HPV is observed3.The cells grow so fast like they are in a cancerous state. This feature provides the cells to be used easily by scientists in their laboratories3,5. But also it could be dangerous. Sometimes they behave aggressively during growing and this situation causes contamination with the other cell cultures2. HeLa cells divide forever. This performance can be explained by telomeres activity, which regenerates telomeres after each division and prevents the gradual shortening of chromosome telomeres. And also telomere shortening is implicated in aging and death1,3.

HeLa cells were used in many important scientific discoveries. Firstly, these cells are used to test the damage effects of radiation, toxins, and other different accumulated chemicals on human cells. They also play an important role in the studying of cancer4. Cancer types are detected with gene mapping and then studying human cells. After research, vaccines developed for many diseases such as polio, HPV, influenza, etc… In additionally, HeLa are cells used in human gene mapping, determining the human chromosome number, Leukemia and Parkinson’s disease treatment, many chemotherapeutic agents, in-vitro fertilization techniques6,7. On the other hand, there are disadvantages to working with these cells. As mentioned before, they grow so fastly. This growth sometimes happens aggressively and cells spread to other cells, which is called contamination. During the studying of these cells, it should be more attentive8.
Rhesus monkey cell was preferred to measure the number of antibodies responding to poliovirus infection and to study it. However, after a while, the monkey cells required for the vaccine test could not be supplied, the structure of HeLa cells was investigated and their suitability was checked. Thanks to its ability to be easily infected by poliovirus, it began to be used as an alternative to the monkey cell9. The degenerate codons for the nine amino acids strain, capsid region of the poliovirus vaccine were replaced with the corresponding non-preferred synonymous codons. Codon substitutions were included in four contiguous intervals covering 97% of the capsid region. With this modification, the infected percentage of the polio virus was considerably reduced. Over time, these studies were advanced and the polio vaccine was developed. In addition, oral polio vaccines have also been developed and used in some countries10.
References:
- Helmenstine, Anne Marie, Ph.D. (2021, February 17). What HeLa Cells Are and Why They Are Important. Retrieved from https://www.thoughtco.com/hela-cells-4160415
- 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
- Janet Ivasa, Wallace Marshall. (2020). Karp’s Cell and Molecular Biology. 92-125.
- Poornima, K., Francis, A. P., Hoda, M., Eladl, M. A., Subramanian, S., Veeraraghavan, V. P., El-Sherbiny, M., Asseri, S. M., Hussamuldin, A., Surapaneni, K. M., Mony, U., & Rajagopalan, R. (2022). Implications of Three-Dimensional Cell Culture in Cancer Therapeutic Research. Frontiers in oncology, 12, 891673. https://doi.org/10.3389/fonc.2022.891673
- Science American, Leah Samuel, 5 Ways Henrietta Lacks Changed Medical Science, April 14,2017. https://www.scientificamerican.com/article/5-ways-henrietta-lacks-changed-medical-science/
- JW Posakony, JM England, G Attardi; Mitochondrial growth and division during the cell cycle in HeLa cells . J Cell Biol 1 August 1977; 74 (2): 468–491. doi: https://doi.org/10.1083/jcb.74.2.468
- National Institutes of Health, Office of Science Policy. https://osp.od.nih.gov/scientific-sharing/hela-cells-timeline/ Date Received:21.11.2022/17:44
- The Embrio Project Encyclopedia, HeLa Cells 50 Years On: The Good, The Bad, and The Ugly” (2002), by John R. Masters, May 02,2021. https://embryo.asu.edu/pages/hela-cells-50-years-good-bad-and-ugly-2002-john-r-masters
- 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(4 Suppl), 5–10. https://doi.org/10.1353/hpu.2012.0151
- Cara Carthel Burns, Jing Shaw, Ray Campagnoli, Jaume Jorba, Annelet Vincent, Jacqueline Quay, Olen Kew. (2006). Modulation of Poliovirus Replicative Fitness in HeLa Cells by Deoptimization of Synonymous Codon Usage in the Capsid Region https://doi.org/10.1128/JVI.80.7.3259-3272.2006
Figure References:
- Are there single-celled organisms that have evolved from multi-cellular ones? Stack ExchangeDate received:21.11.2022 17:30 https://biology.stackexchange.com/questions/31394/are-there-single-celled-organisms-that-have-evolved-from-multi-cellular-ones
- 5 Ways Henrietta Lacks Changed Medical Science.Scientific American Date received:21.11.2022 /17:30 https://www.scientificamerican.com/article/5-ways-henrietta-lacks-changed-medical-science/
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