What are Human Cell Lines?

Human cell lines are organic tools used in biological, genetic, and medical research. Scientists have learned to keep plant and animal cells alive after removing them from organisms, sometimes for an indefinite period. These cells, called cell cultures, can be made to multiply just as they do within the body, creating new cells nearly identical to the originals. These perpetuating cell cultures, called cell lines, are invaluable tools in the development of medicines and vaccines. Human cell lines offer insights into human biology that cell lines from plants or other animals cannot always provide.

In the late 1800s and early 1900s, biologists first learned how to keep cells alive after they had been removed from a living creature. In the 20th century, scientists and medical researchers discovered enormous value in maintaining such cell cultures. They proved vital in the development of vaccines for polio, measles, and other viral diseases. As genetic research advanced, human cell lines offered insights into the human genetic makeup. There are indications that such research may aid the fight against cancer and hereditary diseases.

Early cell cultures did not last long before dying or becoming useless. Scientists soon learned how to maintain such cultures in organic solutions that simulated the body’s nurturing environment. While some, such as blood cells, can be maintained in a liquid solution, others must be adhered to a solid surface to survive. The scientific advantage of using such cells is that they will be free of genetic variations. They thus form a perfect control group that can be used for comparison with other cells that have been changed by the addition of biological material such as viruses or vaccines.

To counter the short lifespan of some cells, human cell lines were encouraged to grow and reproduce; the cell lines could then be distributed to other labs in the same fields of research. Some of these human cell lines can be maintained indefinitely, sometimes long after the cell donor has perished. For this reason, they are colloquially referred to as immortal cell lines. These cells can be genetically manipulated with the addition of new genetic material. The resulting changes provide new insights into genetic markers for diseases such as cancer.

In 2010, the popular science book The Immortal Life of Henrietta Lacks by Rebecca Skloot brought knowledge of human cell lines out of the medical laboratories. Skloot tracked the cell line used in cervical cancer research back to its original owner, Lacks, an African American woman who died of the disease in 1951. Despite the cell line’s wide usage, Lacks’ family was unaware of Henrietta’s contribution to medical science for 25 years. The media coverage of Skloot’s book inspired widespread interest in human cell lines, Lacks herself, and the cell line she originated, still called HeLa by biologists and researchers around the world.