Henrietta Lack and her role in medical sciences

1. STORY OF HENRIETTA LACKS
AND HOW IT CHANGED THE
MEDICAL SCIENCE
PRESENTED BY:
Syeda Tamanna yasmin
M. Sc Microbiology
Department of Life science

2. INTRODUCTION
 Medical researchers use laboratory-grown human cells to learn the
intricacies of how cells work and test theories about the causes and
treatment of diseases.
 The cell lines they need are “immortal”—they can grow indefinitely,
be frozen for decades, 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 valuable, first used in research that led to the Polio
vaccine, as well as helping to develop medicines to fight cancer, the
flu and Parkinson's disease, and in the research that led to gene
mapping and cloning.
 They were used to test the effects of atomic radiation and sent into
outer space, though their donor remained a mystery for decades

3. What is a HeLa cell??
 HeLa cell: One of the cells grown from the cervical
cancer of a young African-American woman, Henrietta
Lacks. HeLa cells were the first human cells to be
continuously grown in culture.
 The cells were first cultured in February 1951 by Drs.
George and Margaret Gey at Johns Hopkins in
Baltimore. The cells appear "immortal" and are still
used in medical research today.
 Who owns those cells? For many years, Lacks's
children have sought recognition of their mother's
contribution to science.
 The designation "HeLa" was taken from the name
of Henrietta Lacks.

4. Some pictures of hela cell:
 The HeLa cell is in
the process of
apoptosis -- a
programmed cellular
death.
 These two HeLa
cells have just
divided -- a process
that will go on for as
long as the cells are
nurtured

5. Microscopic view:
 HeLa cells are
stained with
fluorescent
compounds and
photographed under
a microscope.
 In this multiphoton
fluorescence image,
the microtubules are
stained purple and
the HeLa DNA is
cyan.

6. ABOUT HER
 Henrietta Lacks - She was a black tobacco
farmer from southern Virginia.
 got cervical cancer when she was 30. I
 n 1951, Lacks went to Johns Hopkins Hospital in
Baltimore suffering from cervical cancer.
 Before she died, doctors took some of her tumour
cells for research without ever telling her.
 "They never asked permission to take the cells,
which was standard at the time," Skloot said.
"They just took them." No one knows why, but her
cells never died.

8. Why are her cells so
important
 Henrietta’s cells were the first immortal human cells
ever grown in culture.
 Lacks died later that year, but her cells lived on,
providing a seemingly endless supply for
researchers around the world
 and eventually for companies to sell to sell for profit.
 They 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 scientific landmarks since then have used her
cells, including cloning, gene mapping and in vitro
fertilization.

9. The Science Behind Henrietta Lacks' Immortal Cells
 For one, HeLa cells are prolific dividers. Even among cancers,
these cells were reproductive superstars.
 Secondly, they have an enzyme called telomerase that is
activated during cell division. Normally, it is the gradual
depletion of telomeres — a repetitive strand of DNA on the ends
of the chromosomes — that stops cells from dividing
indefinitely. But active telomerase rebuilds telomeres cut during
division, allowing for indefinite proliferation. So these HeLa
cells, are highly proliferative human cancer cell line with an
active telomerase. That's why they are immortal.
 HeLa cells are not the only immortal cell line from human cells,
but they were the first. Today new immortal cell lines can either
be discovered by chance, as Lacks’s were, or produced through

10. Mechanism of telomerase

11. Cont.
 Genetically, HeLa cells contain parts of Henrietta Lacks’s
own DNA, mutations introduced by the strain or strains of
HPV that infected her, as well as uncounted numbers of
new mutations introduced organically through cellular
division after the original cells were harvested from her
body. A normal human cell has 46 chromosomes — a HeLa
cells tends to have between 70 and 90. They have an active
telomerase during cell division which prevents the
shortening of telomeres.
 The cells have been a boon to biomedical science, playing
a role in the development of the polio vaccine and
thousands of other patented discoveries. HeLa gives
researchers a way to conduct repeatable experiments on
human cells without testing directly on humans, although

18. Normal cells Vs hela cell
 Normal cells have problem called hayflick limit,mean they divide till certain
generations and die. The reason behind this is the telomeres present on
chromosome shorten as the cell divide. where as in cancer cells like Hela,
the telomeres remain same instead of getting shortened there by evading
apoptosis (programmed cell death).
 Its because cancer cells divide indefinitely.. because its cancer ?
Its out of control , its not doing the things of regular stem cells.
 Normally a stem cell would
* have a controlled rate production of child stem cells
* have a controlled rate of production of the specialised celll.
 Normally stem cells produce specialised cells, which do not reproduce, and
a limited number of stem cells (under some control).
 This is just like all life forms, they can reproduce themselves - Outside of
Henrietta Lacks' body, HeLa Cells are effectively a new life form, a single cell
organism just like a bacteria.

19. Contamination
 HeLa cells are sometimes difficult to control because of their
adaptation to growth in tissue culture plates.
 Through improper maintenance, they have been known to
contaminate other cell cultures in the same laboratory,
interfering with biological research and forcing researchers to
declare many results invalid.
 The degree of HeLa cell contamination among other cell
types is unknown because few researchers test the identity or
purity of already established cell lines.
 It has been demonstrated that a substantial fraction of in
vitro cell lines are contaminated with HeLa cells; estimates
range from 10% to 20%. Stanley Gartler (1967) and Walter
Nelson-Rees (1975) were the first to publish on the
contamination of various cell lines by HeLa.
 Science writer Michael Gold wrote about the HeLa cell
contamination problem in his book A Conspiracy of Cells.

20. & how it changed medical
science??
 VACCINATING GIRLS AGAINST CANCER
:scientists used the knowledge to develop HPV
vaccines, which are now widely available
and credited with reducing cases of HPV infection in
teenage girls by almost two-thirds. Harald zur
Hausen won a 2008 Nobel prize for his discovery.
 SHOWING US HOW CELLS STAY YOUNG:Usually,
as cells divide — either as a person grows or as the
body repairs injuries — each division lops off the
ends of chromosomes, called telomeres. Over time
that means that the chromosomes become slightly
shorter, which is thought to be a driver of cell aging.
 ERADICATING POLIO:In the early 1950s, Jonas
Salk had already figured out how the vaccine
(5 important ways Henrietta Lacks changed medical science)

21.  MAPPING THE HUMAN GENOME: In in mid-1960s,
HeLa cells were fused with mouse cells, creating the
first documented human-animal hybrid cells. Those
cells, in turn, became important in the early days of
gene mapping.
 Those techniques evolved over time into the fine-scale
map of the human genome that emerged from the
Human Genome Project.
 CREATING THE FIELD OF VIROLOGY: HeLa cells
with various viruses like HIV, herpes, Zika, measles,
and mumps..etc,to better understand how to battle
them. They discovered, for instance, that the type of
white blood cell called a T cell sports a surface protein
called CD4, which is what HIV uses to enter the cell.
When CD4 was added to HeLa cells they could be

24. When did her family find out
about Henrietta’s cells?
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
and contaminate other cultures. It became an enormous controversy. In
the midst of that, one group of scientists tracked down Henrietta’s
relatives to take some samples with hopes that they could use the
family’s DNA to make a map of Henrietta’s genes so they could tell
which cell cultures were HeLa and which weren’t, to begin
straightening out the contamination problem. So a postdoc called
Henrietta’s husband one day. But he had a third-grade education and
didn’t even know what a cell was. The way he understood the phone
call was: “We’ve got your wife. She’s alive in a laboratory. We’ve been
doing research on her for the last 25 years. And now we have to test
your kids to see if they have cancer.” Which wasn’t what the researcher
said at all. The scientists didn’t know that the family didn’t understand.
From that point on, though, the family got sucked into this world of
research.

26. How did they come to know?
 This was most true for Henrietta’s daughter. Deborah never knew her
mother; she was an infant when Henrietta died. She had always wanted
to know who her mother was but 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: Did it hurt her mother
when scientists injected her cells with viruses and toxins? Had scientists
cloned her mother? And could those cells help scientists tell her about her
mother, like what her favourite color was and if she liked to dance.
 Deborah’s brothers, though, didn’t think much about the cells until they
found out there was money involved. HeLa cells were the first human
biological materials ever bought and sold, which helped launch a multi-
billion-dollar industry.
 When Deborah’s brothers found out that people were selling vials of their
mother’s cells, and that the family didn’t get any of the resulting money,
they got very angry.

27.  Henrietta’s family has lived in poverty most of their
lives, and many of them can’t afford health insurance.
One of her sons was homeless and living on the
streets of Baltimore. So the family launched a
campaign to get some of what they felt they were
owed financially. It consumed their lives in that way.
 As Lacks' family learned more about the medical
advances from HeLa cells, the anger gave way to
pride. "What makes me happy about it is it's
something that my mother has contributed to the
world," said Henrietta's son Sonny. To this day, Lacks'
cells have lead to major medical breakthroughs and
the companies selling her cells make billions of
dollars. Till date, her family had never been paid a
cent, nor been given an apology.

31. Ethitical issues with Hela cells :
 Since the discovery of HeLa cells, they have
been bought and sold for incalculable profit, yet
Henrietta’s family could never afford consistent
health insurance despite suffering from chronic
illnesses.
 The story of Henrietta Lacks is a prime example
of the ethical tradeoffs the scientific community
grapples with in pursuit of the common good, but
it also signalled a turning point.
 It revealed a tangible opportunity for the public
to voice concerns and demand appropriate
measures be taken to learn from past mistakes.

36. BOOK: The immortal Life of Henrietta
Lacks
 The lessons from this book-For scientists,
one of the lessons is that there are human
beings behind every biological sample used in
the laboratory. So much of science today
revolves around using human biological tissue
of some kind. For scientists, cells are often just
like tubes or fruit flies—they’re just inanimate
tools that are always there in the lab. 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.

38. The writer of the book tried to
summarise by the end of thestory:
The story of HeLa cells and what happened with
Henrietta has often been held up as an example of a
racist white scientist doing something malicious to a
black woman. But that’s not accurate. The real story is
much more subtle and complicated. What is very true
about science is that there are human beings behind it
and sometimes even with the best of intentions things
go wrong. One of the things I don’t want people to take
from the story is the idea that tissue culture is bad. So
much of medicine today depends on tissue culture.
HIV tests, many basic drugs, all of our vaccines—we
would have none of that if it wasn’t for scientists
collecting cells from people and growing them. And the
need for these cells is going to get greater, not less.
Instead of saying we don’t want that to happen, we just
need to look at how it can happen in a way that