Henrietta Lacks "immortal" cells

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1 Henrietta Lacks "immortal" cells By Smithsonian.com, adapted by Newsela staff on Word Count 795 TOP: Henrietta Lacks' (left) cells were essential in developing the polio vaccine and were used in scientific landmarks such as cloning, gene mapping and in vitro fertilization. (Courtesy of the Lacks family). SECOND: Scanning electron micrograph of just-divided HeLa cells. Courtesy of National Institutes of Health (NIH) We know no one lives forever, but one woman's cells from 65 years ago seem to be the first immortal cells that scientists have. Until not too long ago, it was a mystery where these cells came from. Medical researchers use laboratory-grown human cells to learn how cells work and test theories about the causes and treatment of diseases. They need cells that can grow indefinitely, be frozen for many years and be divided into different batches and shared among scientists. In 1951, a scientist at Johns Hopkins Hospital in Baltimore, Maryland, created the first immortal human cell line with a tissue sample taken from a young black woman with cervical cancer. Those cells, called HeLa cells, quickly became very important to medical This article is available at 5 reading levels at 1

2 research. But, no one knew much about the donor. In her book, "The Immortal Life of Henrietta Lacks," journalist Rebecca Skloot tracked down the story of the source of the amazing HeLa cells. Who Was Henrietta Lacks? Henrietta was a black tobacco farmer from southern Virginia who had cervical cancer when she was 30. A doctor at Johns Hopkins Hospital took a piece of her tumor without telling her and sent it to scientists who had been trying to grow tissues. No one knows why, but her cells never died. Henrietta s cells were the first immortal human cells ever grown in culture. Grown in culture means cells are taken from their environment, like a human body, to a lab so scientists can grow more of them to study. This is how scientists can learn more about diseases and sickness. This also helps develop immunizations. Henrietta's cells were essential to developing the polio vaccine. They went up in the first space missions to see what would happen to cells in zero gravity. Many scientists have used her cells for different types of research, including cloning, which is making a copy of something. There has been a lot of confusion over the years about the source of HeLa cells. When the cells were taken, they were given the code name HeLa, for the first two letters in Henrietta and Lacks. But, Henrietta's real name wasn't known until the 1970s. Learning Henrietta's Story Skloot first learned about Henrietta in 1988, years before writing her book. Skloot was 16 and in a science class. The teacher knew Henrietta s real name and that she was black. But that s all he knew and Skloot wanted to know more. Did Henrietta have any kids? What do they think about part of their mother's cells being alive all these years after she died? Years later, when Skloot was in college, she decided to find Henrietta's family and write about them. Skloot was determined to tell Henrietta's story. It took almost a year even to convince Henrietta s daughter, Deborah, to talk to Skloot. Skloot went to Clover, Virginia, where Henrietta was raised. Skloot tracked down Henrietta's cousins, then called Deborah and told her their stories. This convinced Deborah to help Skloot learn more about Henrietta because Deborah wanted to know more, too. Deborah never knew her mother; she was an infant when Henrietta died. No one ever talked about Henrietta. So when Deborah found out that this part of her mother was still alive she became desperate to understand what that meant. This article is available at 5 reading levels at 2

3 Finding Out HeLa Is Henrietta Lacks Twenty-five years after Henrietta died, a scientist discovered that many cell cultures thought to be from other tissue types, including breast and prostate cells, were in fact HeLa cells. It turned out that HeLa cells could float on dust particles in the air and travel on unwashed hands into other cell cultures. So, scientists tracked down Henrietta s relatives to take some samples from them to use the family s DNA to make a map of Henrietta s genes. This would allow scientists to know which cell cultures were HeLa and which weren t. It would begin to straighten out the contamination problem. Lessons From The Book For scientists, one of the lessons is that there are human beings behind every biological sample used in the laboratory. Much of science today revolves around using human biological tissue of some kind. The people behind those samples often have their own thoughts and feelings about what should happen to their tissues, but they re usually left out of the equation. Skloot hopes people don't think tissue culture is bad because medicine today depends on tissue culture. The need for these cells is going to get greater, not less, Skloot said. She added that scientists just need to look at how this can happen in a way that everyone is OK with. Many tests, basic drugs and all of our vaccines would not exist if it wasn t for scientists collecting cells and growing them. Or, if it wasn't for Henrietta. This article is available at 5 reading levels at 3

4 Quiz 1 Which answer choice BEST explains the cause of the confusion about where HeLa cells came from? We know no one lives forever, but one woman's cells from 65 years ago seem to be the first immortal cells that scientists have. Until not too long ago, it was a mystery where these cells came from. In 1951, a scientist at Johns Hopkins Hospital in Baltimore, Maryland, created the first immortal human cell line with a tissue sample taken from a young black woman with cervical cancer. When the cells were taken, they were given the code name HeLa, for the first two letters in Henrietta and Lacks. But, Henrietta's real name wasn't known until the 1970s. The people behind those samples often have their own thoughts and feelings about what should happen to their tissues, but they re usually left out of the equation. 2 Which section of the article BEST explains that Henrietta Lacks' cells were taken without her permission? the introduction [paragraphs 1-3] "Who Was Henrietta Lacks?" "Learning Henrietta's Story" "Finding Out HeLa Is Henrietta Lacks" 3 How does the article convey the importance of Henrietta Lacks' cells? by quoting excerpts from a book about the life and impact of Henrietta Lacks by describing events from the childhood of Henrietta Lacks' daughter by detailing the scientific process of collecting and growing HeLa cells by giving examples of the scientific advances made using HeLa cells This article is available at 5 reading levels at 4

5 4 Which answer choice BEST explains Rebecca Skloot's purpose in writing her book? to share information about the life and family of the woman behind the famous HeLa cells to bring fame and fortune to the other members of the Lacks family to show the importance of properly labeling cells in a laboratory to give evidence to suggest that scientists should take human cells without permission This article is available at 5 reading levels at 5