Tragedy to Triumph: the immortal life of Henrietta Lacks

Henrietta Lacks

On February 8th, 1951, a young black American woman, aged 31, was diagnosed with cervical cancer at Johns Hopkins Hospital, Baltimore.

That woman was Henrietta Lacks, and those cells were called HeLa cells, derived from the first two letters of her name and surname.

You are probably wondering what this has got to do with microbiology.

And I’ll tell you: A lot.

To make the diagnosis, Henrietta’s doctor took a biopsy of the lesion in her cervix and sent to the lab. Around that time Dr George Gey, a tissue culture scientist had been trying without success to develop an immortal cell line that could be kept alive in the laboratory. He was given Henrietta’s tumor and he found that, unlike previous cells he had worked with which died after a couple of days, the tumor cells reproduced at an unprecedented rate becoming the first human cells ever to do so. It was in Gey’s lab that Henrietta Lack’s cells were christened HeLa.

HeLa cells have been acclaimed as one of the most important scientific discoveries in the last one hundred years. They allowed scientists perform experiments that would have been impossible with a living human- exposure to toxins, radiation and infections; bombardment with drugs- all, were made possible with the use of those cells.

HeLa cells and microbiology

After undergoing radiation treatment for several months, Henrietta Lacks died on October 4th, 1951.

But her cells were being kept alive by George Gey in the laboratory at Johns Hopkins. Not long after, a factory was established at the Tuskegee Medical centre with the sole aim of churning out HeLa cells in large quantities. The purpose was to help stop the viral disease, polio.

Poliomyelitis is an acute flaccid paralysis caused by polio virus which often results in permanent disability. Bulbar polio which involves respiratory muscles may result in death from respiratory failure. Between 1840 and 1950, polio ravaged the world.At the time of Henrietta’s death, the world was in the midst of the biggest polio epidemic in history. Jonas Salk, an American virologist after years of research had come up with an inactivated polio vaccine. However, the vaccine needed to undergo clinical trials before being adopted into mainstream medical practice. The very first medical breakthrough made possible by HeLa cells was the polio vaccine trials conducted shortly after her death.

A field trial, the largest ever at the time was conducted to test the efficacy of Salk’s inactivated vaccine. Two million children were inoculated with the vaccine and their blood was tested to see if they had responded by producing antibodies. The test, which involved mixing the serum from newly vaccinated children with live polio virus and cells in culture, is called a neutralization test. If the vaccine worked, the serum from a vaccinated child would block the polio virus and protect the cells: if it didn’t work, the virus would infect the cells causing damage known as a cytopathic effect which could be detected microscopically.

Prior to the arrival of HeLa cells, the only cells useful for polio virus research were monkey cells. But monkey cells were expensive. To get enough monkey cells to conduct the trial would have cost millions of dollars. HeLa cells provided a cheap way to prove that the Salk vaccine was effective and the vaccine was pronounced safe on April 12, 1955.

Jonas Salk

HeLa cells were instrumental to the establishment of virology, at that time a fledgling discipline. The cells were exposed to herpes, measles, mumps, fowl pox and equine encephalitis viruses to study how each one entered cells, reproduced and spread.

Beyond microbiology and the moon

At first, the HeLa cells were reserved for polio research, but when it became clear there would be no shortage, they were given to any scientist interested in buying them at a cheap rate.

HeLa cells have been used, since then in tonnes of biomedical research including cancer, AIDS and gene mapping studying the effects of toxic substances and radiation in humans. From aging to mosquito mating, any process related in any way to humans were elucidated using these cells.

While all these were happening, Henrietta Lacks’s family was unaware that the famous HeLa cells originated from their dead relative. By 1973 when her children were shocked to learn their mother’s cells were still alive, HeLa had already been to outer space testing the reaction of human cells to zero gravity.

Full circle: back to microbiology

More than 30 years after her death, research using HeLa cells explained the root cause of Henrietta Lack’s cancer. The German virologist Harald zar Hausen discovered human papilloma viruses(HPV) in the cells. He found HPV type 16 in 1983 and HPV 18 a year later. To verify that these viruses were in the original tumor, he requested for a sample of Henrietta’s biopsy which was still available at Johns Hopkins: the HPV was in situ. We now know that HPV 16 and 18 cause 70% of all cervical cancers.

Throughout the 80s, using HeLa cells, scientists studied human papilloma virus (HPV) infection and how it causes cancer. The discoveries would help lead to a vaccine to prevent cervical cancer and eventually earn Harald zur Hausen the Nobel prize for Physiology/Medicine in 2008.

Tragedy to triumph

It is ironic that the vaccines that could have saved her life all those years ago were developed from Henrietta Lacks’ own cells. Her tragic death in a twist of fate provided the weapons by which medicine has triumphed over diseases that afflict humans including the very one to which she succumbed.

It is estimated that some 50 million metric tonnes of HeLa cells have been cultured in laboratories all over the world. One scientist posits that if you could lay all HeLa cells ever grown end-to-end, they’d wrap around the earth at least three times, spanning more than 350 million feet. More than 60,000 scientific studies have been conducted using the cells and are documented in the literature.

HeLa cells stained with special dyes that highlight specific parts of each cell. The DNA in the nucleus is yellow.

The story of Henrietta Lacks and the ethical controversies emergent from the use of her cancer cells are documented in The Immortal Life of Henrietta Lacks by Rebecca Skloot (which I am currently reading) and portrayed in the HBO movie of the same name, starring Oprah Winfrey. An excerpt from the book, the prologue, as well as many reviews are available on the New York Times and I encourage you to read them in your spare time.

REFERENCES

1. Skloot Rebecca. The Immortal Life of Henrietta Lacks

2. https://en.m.wikipedia.org/wiki/Jonas_Salk

3. ‘The Immortal Life of Henrietta Lacks,’ by Rebecca Skloot https://www.nytimes.com/2010/03/03/books/excerpt-immortal-life-of-henrietta-lacks.html