What are HeLa cells?
If you work in any branch of science, you have likely heard the term “HeLa” and probably know how valuable these cells are to scientific research. These cells are considered immortal because they can continue to grow and divide in vitro (outside of a living organism, i.e. in a test tube). HeLa cells were first collected from the epithelial (outermost) layer of a human cervix in a woman with cervical cancer. These cells are unlike healthy human cells because they are cancerous. Specifically, HeLa cells can continue to grow and divide because of the Human Papilloma Virus (HPV). HPV is able to insert its own viral DNA into the cells of the cervix, which results in the disruption of a tumor suppressing protein p53. HPV is the cause of most cases of cervical cancer. Previously healthy cells are then at risk of uncontrolled divisions and mutations as p53 normally acts as a checkpoint during a cell’s growth and division, inducing death in cells if these mutations are irreparable.
The discovery of HeLa cells has helped scientists develop the polio vaccine, understand how HIV infection works, and learn about cell aging. Scientific labs can order HeLa cells from major lab supplies companies and stored in liquid nitrogen until ready for use. Because these cells are immortal, scientists can use them to study topics from cancer to cellular functioning to environmental factors in vitro, and they can be examined under a microscope. The cells can also be stained to view different parts of the cell and observe cellular changes induced by chemicals and compounds.
Image 1: HeLa cells under a microscope that have been stained with fluorescent dyes
Where did they come from?
As is the case with many scientific discoveries, HeLa cells were discovered unintentionally. In 1951, a working Black mother of five, Henrietta Lacks, went to Johns Hopkins Hospital where she was diagnosed with and subsequently treated for cervical cancer. The physician who treated her also took cervical biopsies, as he did for nearly all of the patients he saw with cervical cancer. Henrietta Lacks’ cells, unlike cells from the other women he collected samples from, did not die, and actually continued to grow and reproduce. Later that year, Lacks died from her cancer. Upon autopsy, it was determined that the cancer had spread throughout her body. As her cells kept growing, the physician who discovered them called them “HeLa,” for the first two letters of her first and last name.
For decades, no one knew what HeLa stood for, or who these cells came from. Her identity became known through the scientific community utilizing these cells in the 1970, years before her own family learned that she was the source of these immortal cells.
Since then, not only has her identity been revealed, but her family medical history in the 1980s and then genome of a strain from HeLa cells in 2013. Her family was kept in the dark through much of these developments and have never profited off of anything related to their matriarch’s cells. Efforts have been made to repair the damages done to them over the years, including conferences, a building at Johns Hopkins School of Medicine in her honor, and the Henrietta Lacks Foundation, which provides financial assistance to families like Henrietta’s who were involved in research without their knowledge or consent.
Image 2: Henrietta Lacks in the 1940s
The Legacy of Henrietta Lacks
Today, many non-scientists are aware of the story of Henrietta Lacks. Her story has brought to light many ethical issues over the years, such as informed consent, profit from patient samples, and genetic privacy.
For many people, being informed about their tissues being donated is critical to allowing or disallowing use of their tissues. A 2005 study found that the majority of people are willing to donate biospecimens for research purposes, but it is largely dependent on the type of biospecimen. It is noteworthy that people are generally more agreeable to donating blood than donating reproductive tissue, for instance. Additionally, an earlier study indicated that people want to be part of the decision-making process regarding the notification procedures should donated tissue be stored long term.
In the United States, researchers are required to notify research participants that they will not receive commercial profit from any donated samples. Most participants accept this condition because privacy concerns are more important. To receive commercial profit for samples, patients would have to have their identity revealed. Apprehension to having their identity revealed are based on t privacy uncertainties regarding racial discrimination, government/corporate exploitation, and discrimination in employment or insurance.
The informed consent that Henrietta Lacks was never given is now federally mandated for any research with human subjects. If genetics is part of the research, an explanation of the Genetic Information Nondiscrimination Act (GINA) must be included in the consent form, and if there is a potential for commercialization based on the research, a statement regarding this must be included as well. Her descendants have no interest in stopping research with HeLa cells. Her third son, Sonny, told Rebecca Skloot, author of The Immortal Life of Henrietta Lacks, “I don’t want to cause problems for science. And besides, I’m proud of my mother and what she done for science.”
Image 3: Seven generations of the Lacks family with a statue honoring Henrietta Lacks
Keywords: HeLa, Henrietta Lacks, research, cancer, ethics
Written By: Amanda Wilburn
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