Categories
Biomedical Research

HeLa Cells: The Turning Point of Medicine?

By Arya Bhatt

Published 2:47 EST, Sun October 31st, 2021

Henrietta Lacks, a black tobacco farmer who died from cervical cancer at the age of 30 in 1951. For many years, scientists were attempting to culture human cells for medical research purposes. Observing how diseases would interact with cells whilst attempting to make beneficial cures is just one example. But the lack of information on required conditions for culture, and how easily these cells would die limited this research greatly. Now that medical knowledge has advanced and knowledge has grown, scientists are aware of the basic conditions required for optimum cell culture. First, all cells require twelve amino acids to synthesize proteins. Furthermore, glutamine is another essential component in the metabolism process. In addition, as expected, cells require a suitable pH of around 7.2 to 7.4, otherwise, there will be harmful effects. But supplying all the nutrients in correct proportions is still problematic and even after those cells are likely to die. Currently, the best form of human cell culture used is embryonic stem cells but this does not provide the greatest depth of research. However, in 1951 a scientist named Dr. Gey observed something extraordinary.

For many years, he was attempting to stimulate the growth of human cells in culture but did not achieve success. One day, when Lacks came into John Hopkins Hospital for a procedure, a small section of her tumour was removed from the cervix and sent to the lab. Dr Gey repeated his experiment as he did with other tumours and cells by setting the sample in his lab to culture. Within a day, he had seen the cells had doubled and needed more space to grow. This process continued until he noticed that the cells would never die as long as the correct space and nutrients are given. The first ‘immortal cells.’ These cells continue to be cultured today and even sent around the world for further medical research. But why were Lacks’ cells so special? The exact reason is unknown but is said that it is a combination of her cancer case being uniquely aggressive, the cells having multiple copies of the HPV genome and the fact that Lacks had syphilis, which weakened her immune system and allowed the cancer to spread further. With her biopsy sample doubling every 20 to 24 hours whilst others would die out meant later on that Dr. Gey created the ‘HeLa cell’ line and was available to researchers for free. These cells did become commercialized later but were not patented and Dr. Gey did not profit from this.

The use of these cells has been magnificent in the field of research and will still continue to be incredibly valuable. For instance, Lacks’ cells have been used to develop vaccinations for Human papillomavirus (HPV). It was seen that the virus entered cells and turned off the gene that would normally suppress the formation of tumours. This knowledge led to the vaccine being developed years later and reduced deaths from HPV by almost two-thirds. But this is quite a specific use as Lacks’ cells were already infected with HPV. There have been multiple wide-scale uses of the cells too. At the time of Lacks’ death, polio was one of the world’s most devastating diseases. HeLa cells helped make the vaccine sooner. Virologist and researcher Jonas Salk figured how the vaccine would work but did not have an efficient testing method. Initially, monkeys’ cells were used which not only killed the cells but were very expensive too. By using HeLa cells, the cells were susceptible to the virus whilst not being killed. This efficient testing method has ensured polio has been eradicated in most countries around the world over the last 60 years.

Furthermore, HeLa cells were utilised in mapping the human genome. HeLa cells were fused with mouse cells creating hybridoma cells. As each hybridoma would have a different combination of genes, scientists could look at what proteins a cell could or could not produce which helped deduce which human gene they were produced by. As HeLa cells can be reproduced in high numbers, they were definitely viable for a study like this. Also, other studies include how human cells are affected when exposed to X-rays and even how Salmonella causes infection. In 1964, HeLa cells were used to study the potential treatment benefits of the Hydroxyurea drug against certain blood cancers and sickle cell anaemia. It showed that Hydroxyurea helps prevent the misshapen red blood cells caused by the genetic mutation responsible for sickle anemia. In the same year, HeLa cells were even sent to space to provide details on how human cells will react to radiation in space when manned missions take place and how astronauts will be impacted. Even now, HeLa cells have been used to study the viral infectivity of SARS-CoV-2 in humans. Studies and research found that coronavirus enters some cells through ACE2 molecules. HeLa cells were engineered to display ACE2 and scientists analyzed how the virus could enter and infect cells.

The development of HeLa cells has evidently been a fantastic breakthrough but is it truly viable and fair? The cells have been used in medical research all over the globe but no one ever asked Lacks consent for the extraction of the tumor cells in the initial procedure. The story of Henrietta Lacks illustrates the deep problem of racial inequality in the US at the time but the main argument involves the fact that healthcare professionals did not obtain consent, and Lacks had no knowledge of her cells being utilised in this manner. So, the use of these cells may be unethical and ‘perpetuates an injustice.’ There are many arguments that the use of HeLa cells should be reduced or even entirely put to a stop. But one thing people need to acknowledge is that each sample in a lab is from a person who has their own life, even if they are helping save numerous lives in the future and contributing to one of the greatest medical research tools.

Arya Bhatt, Youth Medical Journal 2021

References:

Samuel, L., 2017. 5 important ways Henrietta Lacks changed medical science. [online] STAT. Available at: https://www.statnews.com/2017/04/14/henrietta-lacks-hela-cells-science/.

National Institutes of Health. Significant Research Advances Enabled by HeLa Cells. [online] Available at: https://osp.od.nih.gov/scientific-sharing/hela-cells-timeline/#:~:text=HeLa%20cells%20are%20used%20by,use%20it%20to%20this%20day.&text=HeLa%20cells%20are%20taken%20aboard,used%20to%20explore%20outer%20space.

Jackson, N., 2020. Vessels for Collective Progress: the use of HeLa cells in COVID-19 research – Science in the News. [online] Science in the News. Available at: https://sitn.hms.harvard.edu/flash/2020/vessels-for-collective-progress-the-use-of-hela-cells-in-covid-19-research/ 

Kent, C., 2021. Immortal cells and informed consent: the legacy of Henrietta Lacks. [online] Pharmaceutical Technology. Available at: https://www.pharmaceutical-technology.com/features/hela-consent-henrietta-lacks/

Nature. 2020. Henrietta Lacks: science must right a historical wrong. [online] Available at: https://www.nature.com/articles/d41586-020-02494-z

Yang, Z., Xiong H., 2012. IntechOpen. Culture Conditions and Types of Growth Media for Mammalian Cells [online] Available at: https://www.intechopen.com/chapters/40247

Categories
Health and Disease

Stem Cells in Dentistry: A Regenerative Future?

By Arya Bhatt

Published 1:25 EST, Thurs October 21st, 2021

 As seen in a variety of medical applications over multiple years of development, stem cells have been an extraordinary treatment tool for many people. Whether that has been for treatment of blood diseases, fighting cancer or as a method for tissue regeneration, stem cells are continually being developed for the betterment of the whole human population. Now with research in this field escalating on new levels due to the many benefits found, stem cells have been obtained, observed from teeth and put into many dental applications. With multitudes of research that has taken place and will take place in the future, there are excellent prospects of this treatment being widely used as part of dental treatment.

The discovery of stem cells in dental pulp (a layer underneath dentine made up of connective tissue) has vast benefits. Unlike other living organs, teeth possess a limited capacity to repair itself. Furthermore, the anatomy of a tooth is complex and does not just involve the outer layer of enamel we are all aware of. Tooth repair with these stem cells may have much better results which leads to better patient satisfaction and reduced likelihood of complications.

One use of this treatment involves the use of regenerative dental fillings that allow teeth to heal by themselves. The tooth filling would work by stimulating stem cells to encourage the growth of dentine– the main bony material under the hard enamel, which would effectively allow patients to regrow teeth that are damaged through dental disease. The stem cells are obtained from human exfoliated deciduous teeth (SHED). If these treatments are effective and begin to be used in many patients, these patients would be much happier with the result and makes their process of visiting the dentist less intimidating. For example, if a patient’s pulp has been damaged by a bacterial infection, they would normally need a root canal treatment and many are afraid to get this treatment completed due to it being more of an invasive procedure. On the other hand, if stem cell treatments are available, more people would be willing to undergo a simple “filling” to help them recover, and the overall oral health of the community would improve as patients are less hesitant to undergo treatment.

Furthermore, periodontal ligament stem cells are proposed to be effective in periodontitis (severe gum disease). Currently, tests have been completed on pigs and when these stem cells have been transplanted into surgically created periodontal defect areas,which have been seen to regenerate. This could be a favourable treatment method. Rather than a sole relyment on good oral hygiene and professional cleanings in the latter stages of periodontitis, this irreversible disease can be treated to a much higher standard.

However, even though dental treatments using stem cells seem highly attractive, there are some drawbacks. Even when ignoring costs which are currently high for stem cell usage, it is important to note that the obtaining of stem cells from a patient cannot be done at just any point of their lives. Availability is much greater at a younger age. A comprehensive storage solution of these cells would have to be devised.

In the future, if a whole organic tooth can be grown in place of a lost one, this could have fantastic prospects for patients. Rather than being forced to use dentures or having an artificial crown implanted, which can result in complications, a more natural tooth could fill the gap. Patient treatments would be able to be much more personalised, avoiding other complications and challenges. At the moment, treatment is mostly successful with the exception of the misalignment of teeth, rejection that can occur, and the fact that implanted crowns may fall out after insertion if the bone underneath deteriorates. 

In conclusion, dental stem cells are showing a promising future for patient treatment. At the moment, with dental treatment having developed over the years and still not finding vast improvement, it is hard to see where new research will be able to take us. At the moment, dental treatment is highly successful and even greatly satisfying for the patient due to the large number of aesthetic options available. But if research in this area is moved further and is available for a wider use for all patients, the patient satisfaction will greatly improve along with the oral health of the general community.

Arya Bhatt, Youth Medical Journal 2021

References:

Image – Arc Dental. 2018. The Anatomy Of A Tooth In Four Parts – Arc Dental. (online) Available at: https://arcdentalhouston.com/the-anatomy-of-a-tooth-in-four-parts

Bioeden UK. n.d. Stem Cell Therapy and Dental Treatments – Bioeden UK. (online) Available at: https://www.bioeden.com/uk/treatment/dental-treatments

Biol, J., 2015. (online) Avensonline.org. Available at: https://avensonline.org/wp-content/uploads/JOBY-2377-987X-02-0006.pdf

Pharm, M. and Ratan, N., n.d. Repairing Teeth using Stem Cells. (online) News-Medical.net. Available at: https://www.news-medical.net/health/Repairing-Teeth-using-Stem-Cells.aspx