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Are Important</h1> <p class="article-subheading type--dog">The World's First Immortal Human Cell Line</p> </div></div> </div><div class="loc article-post-header"><div id="post-header-social-block_1-0" class="comp post-header-social-block mntl-block"><div id="social-share-block_1-0" class="comp social-share-block mntl-block"><ul id="social-share_1-0" class="comp social-share mntl-social-share share" data-title="What HeLa Cells Are and Why They Are Important" document="StructuredContentDocumentEx{parent=BaseDocumentEx{templateType=STRUCTUREDCONTENT, documentId=4160415, bestTitle='What HeLa Cells Are and Why They Are Important'}}" data-description="Learn what HeLa cells are, why they are important, and how they led to important scientific discoveries as well as legislation about medical ethics." data-tracking-container="true"> <li class="share-item share-item-facebook"> <span 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xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-print" href="#icon-print"></use> </svg> </button> <input type="hidden" value="true" name="print" /> <input type="hidden" value="95727138892decec1a27aac979cf0e85" name="CSRFToken" /> </form></div> <figure id="figure-article_1-0" class="comp figure-article mntl-universal-primary-image lock-primary right-rail__offset figure-landscape primary-image"> <div class="primary-image__media"> <div class="img-placeholder" style="padding-bottom:62.1%;"> <img src="https://www.thoughtco.com/thmb/IsQSy6kfdkx-O1TJjM8cE2ee29o=/1500x0/filters:no_upscale():max_bytes(150000):strip_icc()/hela-cervical-cancer-cells-504644388-5aa7de646bf0690036f1d795.jpg" width="3222" height="2001" srcset="https://www.thoughtco.com/thmb/IsQSy6kfdkx-O1TJjM8cE2ee29o=/1500x0/filters:no_upscale():max_bytes(150000):strip_icc()/hela-cervical-cancer-cells-504644388-5aa7de646bf0690036f1d795.jpg 1500w" sizes="750px" alt="HeLa cervical cancer cells were the first immortal cell line." class=" primary-image__image mntl-primary-image--blurry" onload="(function(e){e.classList.add('loaded')})(this)" style="--blurry: url('data:image/gif;charset=utf-8;base64,R0lGODlhCgAGAPUAAAAAAAEBAQAAAgACAAIAAQMAAAMCAAMBBAICBAUAAQQCAwcBAwIMBAARHxoEBwkiBQslJAAORQYuYQs4bxhvBgtDQE8LGlUFDgBYsQBbwE84vnsrvmVcrUKhfwWDggCsqgfMywD++QD9/gP//gX7+7sCd4xyEcwAA98AAPcDBf0TzP2AEuORLQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACwAAAAACgAGAEUIQwABOIBgIQKLDAA4fEAwQAQKDCoABCiRgMSBDQ8ALBAQQgMAAAwArKAw4kQFAxImfARAAICCAg08mACQ4sJKACA6BAQAOw==')" /> <noscript> <img src="https://www.thoughtco.com/thmb/IsQSy6kfdkx-O1TJjM8cE2ee29o=/1500x0/filters:no_upscale():max_bytes(150000):strip_icc()/hela-cervical-cancer-cells-504644388-5aa7de646bf0690036f1d795.jpg" width="3222" height="2001" class="loaded primary-img--noscript primary-image__image mntl-primary-image--blurry" srcset="https://www.thoughtco.com/thmb/IsQSy6kfdkx-O1TJjM8cE2ee29o=/1500x0/filters:no_upscale():max_bytes(150000):strip_icc()/hela-cervical-cancer-cells-504644388-5aa7de646bf0690036f1d795.jpg 1500w" sizes="750px" alt="HeLa cervical cancer cells were the first immortal cell line." /> </noscript> </div> </div> <figcaption id="primary-image__figcap_1-0" class="comp primary-image__figcap mntl-figure-caption figure-article-caption"> <svg class="icon icon-camera figure-article-caption-icon" > <use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-camera" href="#icon-camera"></use> </svg> <span class="figure-article-caption-text">HeLa cervical cancer cells were the first immortal cell line.</span> <span class="figure-article-caption-owner">HeitiPaves / Getty Images</span> </figcaption></figure> </div><div class="loc article-left-rail"> <div id="breadcrumbs-list_2-0" class="comp breadcrumbs-list " data-tracking-container="true"><a href="https://www.thoughtco.com/science-4132464" 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She has taught science courses at the high school, college, and graduate levels. </div> </div> <div class="mntl-author-tooltip__bottom"> <span class="mntl-author-tooltip__learn-more-text">Learn about our</span> <a href="/about-us-4779650#toc-editorial-guidelines" rel="nocaes" class="mntl-author-tooltip__learn-more-link" >Editorial Process</a> </div> </div></div> </div> <div class="mntl-attribution__item-date">Updated on November 01, 2018</div></div> </div></div> </div><div class="loc article-content"><div id="article-content_1-0" class="comp article-content mntl-block"><div id="mntl-sc-page_1-0" class="comp mntl-sc-page mntl-block structured-content expert-content" data-sc-sticky-offset="85" data-sc-ad-label-height="24" data-sc-ad-track-spacing="100" data-sc-min-track-height="250" data-sc-max-track-height="600" data-sc-breakpoint="50em" data-sc-load-immediate="3" data-sc-content-positions="[1, 1050, 1250, 1550, 1950, 2350, 2750, 3150]" data-bind-scroll-on-start="true"><p id="mntl-sc-block_1-0" class="comp mntl-sc-block mntl-sc-block-html"> HeLa cells are the first immortal human cell line. The cell line grew from a sample of cervical <a href="https://www.thoughtco.com/normal-cells-versus-cancer-cells-373383" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">cancer cells</a> taken from an African-American woman named Henrietta Lacks on February 8, 1951. The lab assistant responsible for the samples named cultures based on the first two letters of a patient's first and last name, thus the culture was dubbed HeLa. In 1953, Theodore Puck and Philip Marcus cloned HeLa (the first human cells to be cloned) and freely donated samples to other researchers. The cell line's initial use was in cancer research, but HeLa cells have led to numerous medical breakthroughs and nearly 11,000 <a href="https://www.thoughtco.com/patent-an-idea-1991747" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="2">patents</a>. </p> <div id="mntl-sc-block_2-0" class="comp mntl-sc-block mntl-sc-block-adslot mntl-block"></div> <div id="mntl-sc-block_3-0" class="comp mntl-sc-block reference-sc-block-callout mntl-sc-block-callout mntl-block theme-keytakeaways" data-tracking-id="mntl-sc-block-callout" data-tracking-container="true"><h3 id="mntl-sc-block-callout-heading_1-0" class="comp mntl-sc-block-callout-heading mntl-text-block">Key Takeaways: HeLa Cells</h3> <div id="mntl-sc-block-callout-body_1-0" class="comp mntl-sc-block-callout-body mntl-text-block"><ul><li>HeLa cells are the first immortal human cell line.</li><li>The cells came from a cervical cancer sample obtained from Henrietta Lack in 1951, without her knowledge or permission.</li><li>HeLa cells have led to many important scientific discoveries, yet there are disadvantages to working with them.</li><li>HeLa cells have led to the examination of the ethical considerations of working with human cells.</li></ul></div></div> <span class="heading-toc" id="toc-what-it-means-to-be-immortal"></span><h2 id="mntl-sc-block_4-0" class="comp mntl-sc-block reference-sc-block-heading mntl-sc-block-heading"> <span class="mntl-sc-block-heading__text"> What It Means to Be Immortal </span> </h2> <p id="mntl-sc-block_5-0" class="comp mntl-sc-block mntl-sc-block-html"> Normally, human cell cultures die within a few days after a set number of <a href="https://www.thoughtco.com/stages-of-mitosis-373534" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">cell divisions</a> via a process called <a href="https://www.thoughtco.com/apoptosis-372446" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="2">senescence</a>. This presents a problem for researchers because experiments using normal cells cannot be repeated on identical cells (clones), nor can the same cells be used for extended study. Cell biologist George Otto Gey took one cell from Henrietta Lack's sample, allowed that cell to divide, and found the culture survived indefinitely if given nutrients and a suitable environment. The original cells continued to mutate. Now, there are many strains of HeLa, all derived from the same single cell. </p> <div id="mntl-sc-block_6-0" class="comp mntl-sc-block mntl-sc-block-adslot mntl-block"></div> <p id="mntl-sc-block_7-0" class="comp mntl-sc-block mntl-sc-block-html"> Researchers believe the reason HeLa cells don't suffer programmed death is because they maintain a version of the enzyme telomerase that prevents gradual shortening of the <a href="https://www.thoughtco.com/dna-replication-3981005" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">telomeres of chromosomes</a>. Telomere shortening is implicated in aging and death. </p> <div id="mntl-sc-block_8-0" class="comp mntl-sc-block mntl-sc-block-adslot mntl-block"></div> <span class="heading-toc" id="toc-notable-achievements-using-hela-cells"></span><h2 id="mntl-sc-block_9-0" class="comp mntl-sc-block reference-sc-block-heading mntl-sc-block-heading"> <span class="mntl-sc-block-heading__text"> Notable Achievements Using HeLa Cells </span> </h2> <p id="mntl-sc-block_10-0" class="comp mntl-sc-block mntl-sc-block-html"> HeLa cells have been used to test the effects of radiation, cosmetics, toxins, and other chemicals on human cells. They have been instrumental in gene mapping and studying human diseases, especially cancer. However, the most significant application of HeLa cells may have been in the <a href="https://www.thoughtco.com/jonas-salk-biography-4171970" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">development of the first polio vaccine</a>. HeLa cells were used to maintain a culture of polio virus in human cells. In 1952, Jonas Salk tested his polio vaccine on these cells and used them to mass-produce it. </p> <div id="mntl-sc-block_11-0" class="comp mntl-sc-block mntl-sc-block-adslot mntl-block"></div> <span class="heading-toc" id="toc-disadvantages-of-using-hela-cells"></span><h2 id="mntl-sc-block_12-0" class="comp mntl-sc-block reference-sc-block-heading mntl-sc-block-heading"> <span class="mntl-sc-block-heading__text"> Disadvantages of Using HeLa Cells </span> </h2> <p id="mntl-sc-block_13-0" class="comp mntl-sc-block mntl-sc-block-html"> While the HeLa cell line has led to amazing scientific breakthroughs, the cells can also cause problems. The most significant issue with HeLa cells is how aggressively they can contaminate other cell cultures in a laboratory. Scientists don't routinely test the purity of their cell lines, so HeLa had contaminated many <em>in vitro</em> lines (estimated 10 to 20 percent) before the problem was identified. Much of the research conducted on contaminated cell lines had to be thrown out. Some scientists refuse to allow HeLa in their labs in order to control the risk. </p> <div id="mntl-sc-block_14-0" class="comp mntl-sc-block mntl-sc-block-adslot mntl-block"></div> <p id="mntl-sc-block_15-0" class="comp mntl-sc-block mntl-sc-block-html"> Another problem with HeLa is that it doesn't have a normal human karyotype (the number and appearance of chromosomes in a cell). Henrietta Lacks (and other humans) have 46 <a href="https://www.thoughtco.com/chromosome-373462" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">chromosomes</a> (diploid or a set of 23 pairs), while the HeLa genome consists of 76 to 80 chromosome (hypertriploid, including 22 to 25 abnormal chromosomes). The extra chromosomes came from the infection by <a href="https://www.thoughtco.com/facts-about-viruses-373886" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="2">human papilloma virus</a> that led to cancer. While HeLa cells resemble normal human cells in many ways, they are neither normal nor entirely human. Thus, there are limitations to their use. </p> <div id="mntl-sc-block_16-0" class="comp mntl-sc-block mntl-sc-block-adslot mntl-block"></div> <span class="heading-toc" id="toc-issues-of-consent-and-privacy"></span><h2 id="mntl-sc-block_17-0" class="comp mntl-sc-block reference-sc-block-heading mntl-sc-block-heading"> <span class="mntl-sc-block-heading__text"> Issues of Consent and Privacy </span> </h2> <p id="mntl-sc-block_18-0" class="comp mntl-sc-block mntl-sc-block-html"> The birth of the new field of biotechnology introduced ethical considerations. Some modern laws and policies arose from ongoing issues surrounding HeLa cells. </p> <div id="mntl-sc-block_19-0" class="comp mntl-sc-block mntl-sc-block-adslot mntl-block"></div> <p id="mntl-sc-block_20-0" class="comp mntl-sc-block mntl-sc-block-html"> As was the norm at the time, Henrietta Lacks was not informed her cancer cells were going to be used for research. Years after the HeLa line had become popular, scientists took samples from other members of the Lacks family, but they did not explain the reason for the tests. In the 1970s, the Lacks family was contacted as scientists sought to understand the reason for the aggressive nature of the cells. They finally knew about HeLa. Yet, in 2013, German scientists <a href="https://www.thoughtco.com/introduction-to-the-human-genome-project-4154188" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">mapped the entire HeLa genome</a> and made it public, without consulting the Lacks family. </p> <div id="mntl-sc-block_21-0" class="comp mntl-sc-block mntl-sc-block-adslot mntl-block"></div> <p id="mntl-sc-block_22-0" class="comp mntl-sc-block mntl-sc-block-html"> Informing a patient or relatives about the use of samples obtained via medical procedures was not required in 1951, nor is it required today. The 1990 Supreme Court of California case of <em>Moore v. Regents of the University of California</em> ruled a person's cells are not his or her property and may be commercialized. </p> <div id="mntl-sc-block_23-0" class="comp mntl-sc-block mntl-sc-block-adslot mntl-block"></div> <p id="mntl-sc-block_24-0" class="comp mntl-sc-block mntl-sc-block-html"> Yet, the Lacks family did reach an agreement with the National Institutes of Health (NIH) regarding access to the HeLa genome. Researchers receiving funds from the NIH must apply for access to the data. Other researchers are not restricted, so data about the Lacks' genetic code is not completely private. </p> <div id="mntl-sc-block_25-0" class="comp mntl-sc-block mntl-sc-block-adslot mntl-block"></div> <p id="mntl-sc-block_26-0" class="comp mntl-sc-block mntl-sc-block-html"> While human tissue samples continue to be stored, specimens are now identified by an anonymous code. Scientists and legislators continue to wrangle with questions of security and privacy, as genetic markers may lead to clues about an involuntary donor's identity. </p> <div id="mntl-sc-block_27-0" class="comp mntl-sc-block mntl-sc-block-adslot mntl-block"></div> <span class="heading-toc" id="toc-references-and-suggested-reading"></span><h2 id="mntl-sc-block_28-0" class="comp mntl-sc-block reference-sc-block-heading mntl-sc-block-heading"> <span class="mntl-sc-block-heading__text"> References and Suggested Reading </span> </h2> <ul id="mntl-sc-block_29-0" class="comp mntl-sc-block mntl-sc-block-html"> <li><cite>Capes-Davis A, Theodosopoulos G, Atkin I, Drexler HG, Kohara A, MacLeod RA, Masters JR, Nakamura Y, Reid YA, Reddel RR, Freshney RI (2010). "Check your cultures! A list of cross-contaminated or misidentified cell lines". <em>Int. J. Cancer</em>. <strong>127</strong> (1): 1–8.</cite></li><li><cite>Masters, John R. (2002). "HeLa cells 50 years on: The good, the bad and the ugly". <em>Nature Reviews Cancer</em>. <strong>2</strong> (4): 315–319.</cite></li><li><cite>Scherer, William F.; Syverton, Jerome T.; Gey, George O. (1953). "Studies on the Propagation in Vitro of Poliomyelitis Viruses". J Exp Med (published May 1, 1953). 97 (5): 695–710.</cite></li><li><cite>Skloot, Rebecca (2010). <em>The Immortal Life of Henrietta Lacks</em>. New York: Crown/Random House.</cite></li><li><cite>Turner, Timothy (2012). "Development of the Polio Vaccine: A Historical Perspective of Tuskegee University's Role in Mass Production and Distribution of HeLa Cells". <em>Journal of Health Care for the Poor and Underserved</em>. <strong>23</strong> (4a): 5–10. </cite></li> </ul></div> <div id="sources-and-citation_1-0" class="comp sources-and-citation mntl-block"><div id="citation-widget_1-0" class="comp citation-widget js-citation-widget" data-tracking-container="true"> <div class="citation-widget__container js-container"> <button class="citation-widget__button js-button"> <span class="citation-widget__cite-label">Cite this Article </span> <svg class="icon icon-cite citation-widget__icon-cite" > <use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-cite" href="#icon-cite"></use> </svg> </button> <div class="citation-widget__window js-window"> <svg class="icon icon-close citation-widget__icon-close js-icon-close" > <use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-close" href="#icon-close"></use> </svg> <div class="citation-widget__heading">Format</div> <a href="#" class="citation-widget__format-link citation-widget__format-link--active js-format-link">mla</a> <a href="#" class="citation-widget__format-link js-format-link">apa</a> <a href="#" class="citation-widget__format-link js-format-link">chicago</a> <div class="citation-widget__heading">Your Citation</div> <div class="citation-widget__content js-content"> <span class="citation-widget__citation citation-widget__citation--active js-active" data-citation-format="mla">Helmenstine, Anne Marie, Ph.D. "What HeLa Cells Are and Why They Are Important." ThoughtCo, Feb. 17, 2021, thoughtco.com/hela-cells-4160415.</span> <span class="citation-widget__citation" data-citation-format="apa">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</span> <span class="citation-widget__citation" data-citation-format="chicago">Helmenstine, Anne Marie, Ph.D. "What HeLa Cells Are and Why They Are Important." ThoughtCo. https://www.thoughtco.com/hela-cells-4160415 (accessed November 25, 2024).</span> </div> <div class="citation-widget__copy-container"> <button class="citation-widget__copy-button js-copy-button"> <div class="citation-widget__copy-wrapper"> <svg class="icon icon-checkmark citation-widget__icon-checkmark" > <use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-checkmark" href="#icon-checkmark"></use> </svg> <span class="citation-widget__copy-label js-copy-label">copy citation</span> </div> </button> </div> </div> </div> </div></div></div> </div><div class="loc article-right-rail"><div id="mm-ads-right-rail_1-0" class="comp mm-ads-right-rail mntl-block"><div id="sc-billboard-group_1-0" class="comp sc-billboard-group mntl-block js-scads-inline-content"><div id="mntl-block_2-0" class="comp mntl-block"><div id="ref-billboard1-sticky-dynamic_1-0" class="comp ref-billboard1-sticky-dynamic mntl-block"><div id="mm-ads-sc-sticky-square-ad_1-0" class="comp 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