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Although initially HeLa was developed for use in cancer research, that was just a start. HeLa cells have even been sent to outer space, proving that cancer cells can grow there. Almost since its creation, the HeLa cell line has been used in many different ways, and it even helped found entire fields of study. For example, doctors essentially created the field of virology -- the study of viruses -- after infecting HeLa cells with everything from measles to mumps so they could observe how the viruses affected the cells. This led to the creation of some of the vaccines in use today. Genetic medicine might not be possible without HeLa cells, as researchers discovered that the cells' chromosomes were visible when treated with a specific stain. In the mid-1960s, HeLa cells were fused with mouse embryo cells to create the first cell hybrid, which helped researchers begin the process of mapping the human genome.

Many Nobel prizes have been awarded for research involving

HeLa cells (5 since 2001)

1) telomerase activity

2) cell cycle regulation

3) protein transport

4) cell division

5) cell adhesion

6) signal transduction

7) apoptosis

8) virology

HeLa Cells: the "Immortal Cell" line

"HeLa Cells"

The Basics

They are a cell type in an "immortal cell line" used in scientific research. The line was taken from the cervical cancer of a woman named Henrietta Lacks circa 1951. They were the first cells to survive in vitro.

These cells are now as commonly found in biology labs as lab coats and petri dishes. It is estimated that the mass of all of the HeLa cells that have been produced would've outweighed Henrietta Lacks herself!

In 1955, they were the first cells to be cloned.

HeLa cells are some of the most commonly used cells in biomedical research.

Elizabeth Winkelhoff

The Henrietta Lacks Story

A Woman contracts cervical cancer

Dr. George Otto Gey

In January 1951, Lacks was sent to Johns Hopkins hospital and was diagnosed with a malignant epidermoid carcinoma of the cervix.

Lacks' doctor was given two samples of her cervix (one healthy and one cancerous), without consent, that will ultimately become the HeLa immortal cell line. Dr. Gey didn't seek to profit off HeLa, though. After publishing his research, he received requests from other researchers for samples of HeLa, and he was happy to provide them for free. Now HeLa cells are being used all around the world, with more than 60,000 medical journal articles published about their use and at least 11,000 patents related to their use. There are thousands of other cell lines, but HeLa remains the most popular because it is easy to grow, store and ship.

Her Legacy

The cells from Henrietta's tumor were given to researcher George Gey, who "discovered that the cells did something they'd never seen before: They could be kept alive and grow." Before this, cells cultured from other cells would only survive for a few days. Scientists spent more time trying to keep the cells alive than performing actual research on the cells, but some cells from Lacks's tumor sample behaved differently from others. George Gey was able to isolate one specific cell, multiply it, and start a cell line. Gey named the sample HeLa, after the initial letters of Henrietta Lacks' name. As the first human cells grown in a lab that were "immortal" (they do not die after a few cell divisions), they could be used for conducting many experiments. This represented an enormous boom to medical and biological research.

Bioethics

The moral and ethical issues surrounding HeLa cells and other human cell lines are still much debated.

Gey and Johns Hopkins didn't profit off HeLa, but the cells and related products have been sold since 1954. The Lacks family has not received any money, and they cannot afford health insurance. Her children received very little education, and many of them have health problems. They're angry, and critics have argued that at the very least, they've been marginalized and disrespected.

Today patients sign consent forms stating that tissues can be used in research, but the argument used by the medical community is that once blood or tissues are removed from you, they're not really yours anymore. It would be far too complicated, and would ruin the field of medical research, to have to track the identities of each sample and pay if there's monetary gain. The courts have sided with researchers so far. In the 1980 case of Moore vs. Regents of the University of California, a leukemia patient discovered that his doctor had filed a patent and created a cell line worth $3 billion using his cells. The Supreme Court ruled that Moore had no right to share in the profits.

The Uses

HPV

And its role in cervical cancer

HeLa cells have been shown to contain human papillomavirus (HPV) 18 DNA11 and HPV18-positive HeLa cells have been linked to changes in microRNA expression.

A German virologist, Harald zur Hausen, discovered a new strain of Human Papilloma Virus HPV-18, which he believed caused cervical cancer. A sample of Lacks’s original biopsy showed that she had been infected with multiple copies of what would turn out to be one of the most virulent strains of HPV. Working with HPV in HeLa and other cells led scientists to a vaccine for cervical cancer and earned zur Hausen a Nobel prize in 2008.

HIV identification

The Polio Vaccine

Human immunodeficiency virus, HIV, is a virus, and viruses can only reproduce by infecting pre-existing cells and inserting their own genetic material. In the 1980s (1986), scientists used HeLa cells and infected them with HIV to study their virus infection mechanism and proved that CD4 was the HIV acceptor in cells. It then lead to the first treatments, such as AZT.

Poliomyelitis is a disease caused by infection with the poliovirus. The virus spreads by direct person-to-person contact, by contact with infected mucus or phlegm from the nose or mouth, or by contact with infected feces.

HeLa cells were used by Jonas Salk to test the first polio vaccine in the 1950s. They were observed to be easily infected by poliomyelitis, causing infected cells to die. This made HeLa cells highly desirable for polio vaccine testing since results could be easily obtained. A large volume of HeLa cells were needed for the testing of Salk’s polio vaccine, prompting the National Foundation for Infantile Paralysis (NFIP) to find a facility capable of mass-producing HeLa cells. In the spring of 1953, a cell culture factory was established at Tuskegee University to supply Salk, as well as other labs, with HeLa cells. Less than a year later, Salk’s vaccine was ready for human trials.

Cloning

HeLa cells were the first to be cloned. The early cloning technology that started because of HeLa cells led to many other advances that also necessitated the ability to grow cells in culture. Such advances included isolating stem cells, cloning entire animals (Dolly the sheep), and in vitro fertilization.

The "Immortal" Cell Line

Works Cited

Contamination

  • Zielinski, Sarah. "Henrietta Lacks' 'Immortal' Cells." Smithsonian. N.p., n.d. Web. 08 June 2014. <http://www.smithsonianmag.com/science-nature/henrietta-lacks-immortal-cells-6421299/?no-ist>.
  • "The Amazing HeLa Cells of Henrietta Lacks." Virology Blog RSS. N.p., n.d. Web. 09 June 2014. <http://www.virology.ws/2009/02/09/the-amazing-hela-cells-of-henrietta-lacks/>.
  • Freeman, Shanna. "How HeLa Cells Work." HowStuffWorks. HowStuffWorks.com, 10 Sept. 2012. Web. 08 June 2014. <http://science.howstuffworks.com/life/cellular-microscopic/hela-cell.htm>.
  • Voorhies, Steve. "University of Arkansas." University Scientist Uses HeLa Cells in HIV Research. N.p., n.d. Web. 09 June 2014. <https://newswire.uark.edu/articles/14819/university-scientist-uses-hela-cells-in-hiv-research>.
  • "Comparative Study of the Persistence of Anti-HIV Activity of Deoxynucleoside HIV Reverse Transcriptase Inhibitors after Removal from Culture." AIDS Research and Therapy. N.p., n.d. Web. 09 June 2014. <http://www.aidsrestherapy.com/content/6/1/5>.
  • "Available Technologies." N.p., n.d. Web. 09 June 2014. <http://is-ext.fhcrc.org/sites/public/apps/techtrans/detail.php?101161>.
  • Kappel, Hunter. "Henrietta Lacks and Her "Immortal Cells"" Henrietta Lacks and Her “Immortal” Cells (n.d.): n. pag. Dartmouth.edu. Web. 08 June 2014. <http://dujs.dartmouth.edu/wp-content/uploads/2011/06/11s_final-12-13.pdf>.
  • "HeLa Cells: A New Chapter in An Enduring Story." NIH Directors Blog. N.p., n.d. Web. 09 June 2014. <http://directorsblog.nih.gov/2013/08/07/hela-cells-a-new-chapter-in-an-enduring-story/>.
  • "Polio." The Immortal Life of Henrietta Lacks. N.p., n.d. Web. 09 June 2014. <http://fyb.umd.edu/2011/polio.html>.
  • Rivard, Laura, PhD. HeLa: Immortal Cells, Enduring Questions (n.d.): n. pag. Web. 08 June 2014. <http://catcher.sandiego.edu/items/cee/HeLa%20Powerpoint.pdf>.
  • Flanick, Lindsey. "13.04.03: Cell Biology: From HeLa Cells to the Polio Vaccine." 13.04.03: Cell Biology: From HeLa Cells to the Polio Vaccine. N.p., n.d. Web. 09 June 2014. <http://www.yale.edu/ynhti/curriculum/units/2013/4/13.04.03.x.html>.
  • Beyerstein, Lindsay. "Nobel Prize Awarded to Virologist Who Linked HPV to Cervical Cancer." RH Reality Check. N.p., n.d. Web. 09 June 2014. <http://rhrealitycheck.org/article/2008/10/21/nobel-prize-awarded-virologist-who-linked-hpv-cervical-cancer/>.
  • "Quick Guide to HeLa Cells | Wellcome Trust." Quick Guide to HeLa Cells | Wellcome Trust. N.p., n.d. Web. 09 June 2014. <http://www.wellcome.ac.uk/Education-resources/Education-and-learning/Big-Picture/All-issues/The-Cell/WTDV030785.htm>.
  • "Result Filters." National Center for Biotechnology Information. U.S. National Library of Medicine, n.d. Web. 09 June 2014. <http://www.ncbi.nlm.nih.gov/pubmed/17685229>.
  • "The Immortal Life of Henrietta Lacks: A Bittersweet Legacy." The Telegraph. Telegraph Media Group, 21 June 2010. Web. 09 June 2014. <http://www.telegraph.co.uk/science/7845119/The-Immortal-Life-of-Henrietta-Lacks-a-bittersweet-legacy.html>.

Because of their adaptation to growth in tissue culture plates, HeLa cells are sometimes difficult to control. They have proven to be a persistent laboratory "weed" that contaminates other cell cultures in the same laboratory, interfering with biological research and forcing researchers to declare many results invalid. The degree of HeLa cell contamination among other cell types is unknown because few researchers test the identity or purity of already-established cell lines. It has been demonstrated that a substantial fraction of in vitro cell lines — estimates range from 10% to 20% — are contaminated with HeLa cells. Recent data suggest that cross-contamination is still a major ongoing problem with modern cell cultures. A cell line is considered to be misidentified if it no longer corresponds to the individual from whom it was first established. Many cases of misidentification are caused by cross-contamination, where another, faster growing, cell line is introduced into that culture.

The Chromosome Number

New Species?

Due to their ability to replicate indefinitely, and their non-human number of chromosomes, HeLa was described by Leigh Van Valen as an example of the contemporary creation of a new species, Helacyton gartleri. The species was named after Stanley M. Gartler, whom Van Valen credits with discovering "the remarkable success of this species." His argument for speciation depends on these points:

1) The chromosomal incompatibility of HeLa cells with humans.

2) The ecological niche of HeLa cells.

3) Their ability to persist and expand well beyond the desires of human cultivators.

4) HeLa can be defined as a species as it has its own clonal karyotype.

However this proposal has not been taken seriously by other prominent evolutionary biologists or scientists in other disciplines. Van Valen’s argument of HeLa being a new species does not fulfill the criteria for an independent unicellular asexually reproducing species because of the notorious instability of the cancer karyotype and their lack of a strict ancestral-descendant lineage.

Horizontal gene transfer from human papillomavirus 18 (HPV18) to human cervical cells created the HeLa genome which is different from Henrietta Lacks' genome in various ways, including its number of chromosomes. HeLa cells are rapidly dividing cancer cells, and the number of chromosomes varied during cancer formation and cell culture. The current estimate (excluding very tiny fragments) is a "hypertriploid chromosome number (3n+)" which means 76 to 80 total chromosomes (rather than the normal diploid number of 46) with 22–25 clonally abnormal chromosomes, known as HeLa signature chromosomes". The signature chromosomes can be derived from multiple original chromosomes making challenging summary counts based on original numbering.

Researchers have also noted how stable these aberrant karyotypes can be.

How They Work

HeLa cells were the first line of human cells to survive in vitro (in a test tube). Named after a cancer patient, the cells were taken from Lacks' tissue samples and grown by a researcher named Dr. George Gey in 1951. Dr. Gey quickly realized that some of Lacks' cells were different from normal cells. While those died, they just kept on growing. After more than 50 years, there are now billions and billions of HeLa cells in laboratories all over the world. It's the most commonly used cell line, and it's known to be extremely resilient. HeLa cells grow and spread quickly in vitro. Nobody knows quite why. Lacks had both the human papillomavirus (HPV) and syphilis, so one theory is that these helped suppress PCD in the cells.

The HeLa cell line was derived for use in cancer research. These cells proliferate abnormally rapidly, even compared to other cancer cells. Like many other cancer cells, HeLa cells have an active version of telomerase during cell division, which prevents the incremental shortening of telomeres that is implicated in aging and eventual cell death. In this way the cells circumvent the Hayflick Limit, which is the limited number of cell divisions that most normal cells can later undergo before becoming senescent.

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