Over 100 years have passed, she was born in 1920 in Virginia, U.S.A., and yet she is still omnipresent among us throughout the globe within the scientific community. She is no one else but ‘Henrietta Lacks’ many of us don’t know her name, she was no researcher nor a scientist but according to Rebecca Skloot (author of “The Immortal Life of Henrietta Lacks”), by 2009, more than 60,000 scientific articles published had a contribution of her, and that number is still increasing steadily at a rate of more than 300 papers each month.
This article is all about HeLa cell, an immortal cell line that is widely used in scientific research. It is the oldest and most commonly used human cell line derived from cervical cancer cells taken on February 8, 1951, from Henrietta Lacks but without her knowledge or consent.
Dr. George Otto Gey, a cell biologist at Johns Hopkins Medical School & Hospital is credited with propagating the HeLa cell line from Henrietta Lacks’s cell samples. It was observed that the cells grew robustly, doubling every 20–24 hours, unlike previous specimens that died out. This was the first human cell line to prove successful in vitro, which was a scientific achievement with a profound future benefit to medical research. The cell line was named "HeLa" after the first two letters in Lacks’s name. Gey freely donated these cells along with the tools and processes that his lab developed to any scientist requesting them simply for the benefit of science. Neither Lacks nor her family gave permission to harvest the cells but, at that time, permission was neither required nor customarily sought. The cells were later commercialized, although never patented in their original form. There was no requirement at that time (or at present) to inform patients or their relatives about such matters because discarded material or material obtained during surgery, diagnosis, or therapy was the property of the physician or the medical institution.
HeLa cells, like other cell lines, are termed "immortal" in that they can divide an unlimited number of times in a laboratory cell culture plate as long as fundamental cell survival conditions are met (i.e. being maintained and sustained in a suitable environment). There are many strains of HeLa cells as they continue to mutate in cell cultures, but all HeLa cells are descended from the same tumor cells removed from Lacks. The total number of HeLa cells that have been propagated in cell culture far exceeds the total number of cells that were in Henrietta Lacks's body.
HeLa cells were the first human cells to be successfully cloned in 1953 by Theodore Puck and Philip I Marcus at the University of Colorado, Denver. Since that time, HeLa cells have continually been used for research into cancer, AIDS, the effects of radiation and toxic substances, gene mapping, and countless other scientific pursuits. Some notable mentions include their use by Jonas Salk to test the first polio vaccine in the 1950s.
In 1953, a lab mistake involving mixing HeLa cells with the wrong liquid allowed researchers to see and count each chromosome clearly in the HeLa cells they were working with for the first time. The accidental discovery led scientists Joe Hin Tjio and Albert Levan to develop better techniques for staining and counting chromosomes. They were the first to accurately describe that humans have 23 pairs of chromosomes rather than 24, as was previously believed.
In 1965, Henry Harris and John Watkins created the first human-animal hybrid by fusing HeLa cells with mouse embryo cells. This enabled advancements in mapping genes to specific chromosomes, which would eventually lead to the Human Genome Project.
In the 1960s, HeLa cells were sent on the first satellite and human space missions to determine the long-term effects of space travel on living cells and tissue. Scientists discovered that HeLa cells divided even more quickly in zero gravity.
Even though some information about the origins of HeLa's immortalized cell lines was known to researchers after 1970, the Lacks family was not made aware of the line's existence until 1975. In March 2013, researchers published the DNA sequence of the genome of a strain of HeLa cells. The Lacks family discovered this when the author Rebecca Skloot informed them. There were objections from the Lacks family about the genetic information that was available for public access. Jeri Lacks Whye, a grandchild of Henrietta Lacks, said to The New York Times, "the biggest concern was privacy - what information was actually going to be out there about our grandmother, and what information they can obtain from her sequencing that will tell them about her children and grandchildren and going down the line." That same year another group working on a different HeLa cell line's genome under National Institutes of Health (NIH) funding submitted it for publication. In August 2013, an agreement was announced between the family and the NIH that gave the family some control over access to the cells' DNA sequence found in the two studies along with a promise of acknowledgment in scientific papers. In addition, two family members will join the six-member committee which will regulate access to the sequence data.
With knowledge of the cell line's genetic provenance becoming public, its use for medical research and for commercial purposes continue to raise concerns about privacy and patients' rights.
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