Friday, January 16, 2015

The Immortal Life of Henrietta Lacks

For Christmas I received a portable CD player to replace one that was broken, so I am now back in business listening to audio books while walking my dog Suki. This week I finished The Immortal Life of Henrietta Lacks by Rebecca Skloot. The book explains how a biopsy from a fatal tumor led to the most famous cell line used in medical research: HeLa.

HeLa cells are grown in cell culture. Russ Hobbie and I describe cell culture experiments in the 4th edition of Intermediate Physics for Medicine and Biology, when discussing the biological effects of radiation.
16.10.1 Cell Culture Experiments

Cell-culture studies are the simplest conceptually. A known number of cells are harvested from a stock culture and placed on nutrient medium in plastic dishes. The dishes are then irradiated with a variety of doses including zero as a control. After a fixed incubation period the cells that survived have grown into visible colonies that are stained and counted. Measurements for many absorbed doses give survival curves such as those in Fig. 16.32. These curves are difficult to measure for very small surviving fractions, because of the small number of colonies that remain.”
Russ and I don’t mention HeLa cells in IPMB, but they played a key role in establishing how cells respond to radiation. For instance, Terasima and Tolmach measured Variations in Several Responses of HeLa Cells to X-Irradiation during the Division Cycle (Biophysical Journal, Volume 3, Pages 11-33, 1963), and found that “survival (colony-forming ability) is maximal when cells are irradiated in the early post-mitotic (G1) and the pre-mitotic (G2) phases of the cycle, and minimal in the mitotic (M) and late G1 or early DNA synthetic (S) phases.” Russ and I discuss these observations in Section 16.10.2 about Chromosome Damage: “Even though radiation damage can occur at any time in the cell cycle (albeit with different sensitivity), one looks for chromosome damage during the next M phase, when the DNA is in the form of visible chromosomes.”

Skloot’s book not only explains HeLa cells and their role in medicine but also describes the life and death of Henrietta Lacks (1920-1951). Her cervical cancer was treated at Johns Hopkins University by a primitive type of brachytherapy (see Section 17.15 of IPMB) in which tubes of radium where placed near the tumor for several days. The treatment failed and Lacks soon died from her aggressive cancer, but not before researcher George Gey obtained a biopsy and used it to create the first immortal human cell line.

The Immortal Life of Henrietta Lacks is about more than just HeLa cells and Henrietta. It also describes the story of how the Lacks family--and in particular Henrietta’s daughter Deborah--learned about and coped with the existence of HeLa cells. In addition, it is a first-person account of how Skloot came to know and gain the trust of the Lacks family. Finally, it is a case study in medical ethics, exploring the use of human tissues in research, the growing role of informed consent in human studies, and the privacy of medical records. The public’s perception of medical research and the view of those doing the research can be quite different. In 2013, the National Institutes of Health and the Lacks family reached an understanding about sharing genomic data from HeLa cells. With part of the income from her book, Skloot established the Henrietta Lacks Foundation to support the Lacks family.

It looks like Suki and I are again enjoying audio books on our walks (for example, see here and here). At least I am; I’m not sure what Suki thinks about it. I hope all the books are all this good.

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