HeLa Cells, Part 2: Uses and the "HeLa Bomb"
In 1951, the world was facing a polio epidemic. Jonas Salk
thought he’d invented a polio vaccine. If Salk was right, this was a godsend.
But could one risk injecting it into kids world over? And how to test it on a
massive scale for side-effects? And so the US turned to HeLa, writes Rebecca
Skloot in The Immortal Life of Henrietta
Lacks. They created a “HeLa factory”,
to produce cells on an “enormous, industrial scale”. The fact that HeLa cells
could be shipped by mail, without too much paraphernalia to protect or preserve
them, was a huge bonus. And thus HeLa cells “helped prove the Salk vaccine
effective”.
The avalanche of uses of HeLa had just got
started:
- As scientists began to understand viruses, “researchers began exposing (HeLa cells) to viruses of all kinds” to test for their effects.
- Another set used HeLa to find ways to freeze cells without damaging or changing them. This ability to freeze, aka “pause”, in turn created other uses. Scientists could pause cells at different stages, and then press “play” on them at the same time to compare them all in real time!
- A happy mistake in a lab helped count the number of chromosomes in a human cell. That in turn allowed for knowing if a fetus had too many (or few) chromosomes, something likely to lead severe problems in fetal development.
- This being the Cold War era, HeLa cells were exposed to nuclear bomb levels of radiation to see the damage they cause, and if it could be reversed.
- They were put in high speed centrifuges thereby exerting tremendous pressure to see the effects of “deep-sea diving and spaceflight”.
- Cosmetic and pharma companies used HeLa cells to test for cell damage caused by their products.
- HeLa cells were sent into space along with the first humans, leading to a very disturbing finding:
- “Noncancerous cells grew normally in orbit, but HeLa became more powerful, dividing faster with each trip.”
- When scientists learned to fuse cells, they fused HeLa cells with mouse cells, making it possible to move along the study of how genes worked. It also meant that DNA from different species could co-exist within a fused cell, “which meant the mechanism for rejecting transplanted organs had to be outside cells”.
Very
impressive indeed.
And
then came the “HeLa bomb”. Studies should be done on cells from multiple
sources for validity. In 1964, Stanley Gartler said an ordinate fraction of
cells used in studies seemed to have the same cells: HeLa. His explanation?
“It seems to me
the simplest explanation is that they are all HeLa cell contaminants.”
It
turned out that HeLa cells could travel from one culture to another on dust
particles, “unwashed hands or used pipettes”:
“And they were
strong: if just one
HeLa cell landed in a culture dish, it took over, consuming all the media and
filling all the space.”
The
implications were horrifying:
“If all those
cells were in fact HeLa, it would mean millions of dollars had been wasted.”
As is
often the case, when a prospect threatens to undermine almost all research in a
field, scientists just ignored the HeLa bomb and went back to business as usual.
Until, in 1972, the Russians said they’d found a cancer virus in cells from
Russian patients. When the Americans checked them, they found the cells weren’t
Russian, they were HeLa. The press reported this, and the HeLa bomb warning was
now news: how much of other research was invalid?
It’s a
question that we don’t know the answer to, even today. But clearly the answer
can’t be that all the research is invalid.
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