HeLa cell line copy, origin, their features

This presentation gives information about the HeLa cell lines, about their origin, their features, how they are different from normal cells, and what are their specialities, ethical issues related with the cells.

1. HeLa cell line
PRESENTED BY: NANCY
ROLL NO: 30610
MSC. BIOTECHNOLOGY 3
RD
SEMESTER

2. Questions to be considered…..
What is a cell line?
What are HeLa cells?
What milestones in cell biology possible because of HeLa cells?
Normal cell vs HeLa cells
Ethical issues with HeLa cells

3. Henrietta Lacks

4. Henrietta Lacks
She was a poor, black, farmer.
She was born in 1920 and died on October 4, 1951 from cervical cancer.
In 1951, Henrietta went to Johns Hopkins for treatment of her cervical cancer (
died later in 1951)
Tissue sample was taken without consent – given to Dr. George Gey
without her knowing, the cells from her cancerous tumour were cultured
(grown in laboratory) to create the first known human immortal cell line for
medical research
This is now known as the HeLa cell line.
The designation “HeLa” was taken from the name of Henrietta lacks.

5. Henrietta’s tumour cells
They could be kept alive and grow.
Before this, cells cultured from other cells would only survive for a few days.
Scientists spend more time trying to keep the cells alive than performing actual research
on the cells.

6. HeLa cells
HeLa cells are stained
with fluorescent
compounds and
photographed under
a microscope.

7. Why are her cells
so important?

14. What milestones in cell biology were
possible because of HeLa cells?
Polio infection process and vaccine development
 research to isolate single cells and eventually establish clonal cell lines.
Methods established for chromosome spreading
Ongoing research for telomerase ( Noble prize 2009)
Research into cancer, AIDS, the effect of radiation and toxic substances,
gene mapping, in vitro fertilisation and countless other scientific pursuits.
Scientists have grown some 20 tons of her cells, and there are almost
11,000 patents involving HeLa cells. The cells have been used in 74,000
studies.

16. Normal cells vs HeLa cells
1- HeLa cells are cancerous. The difference between normal cells and HeLa
cells is most visible when you look at the chromosomes (karyotype).HeLa
cells, like many tumours, have error-filled genomes, with one or more copies of
many chromosomes: a normal cell contains 46 chromosomes whereas HeLa
cells contain 76 to 80) total chromosomes, some of which are heavily mutated
(22-25), per cell.This is due to theHuman Papillomavirus (HPV), the cause of
nearly all cervical cancers. HPV inserts its own DNA into host cells and the
additional DNA results in the production of ap53-binding protein which
inhibits it and prevents native p53 from repairing mutations and suppressing
tumours, causing errors in the genome to accumulate as unchecked cellular
divisions occur.
2- HeLa cells are immortal, meaning they will divide again and again and
again… This performance can be explained by the expression of an overactive
telomerase that rebuilds telomeres after each division, preventing cellular
aging and cellular senescence, and allowing perpetual divisions of the cells.

17. 3- HeLa cells grow unusually fast, even considering their cancerous state.
Indeed, HeLa cells grow easily and rapidly, doubling cellular count in only
24 hours, making them ideal for large scale testing. They grow so fast that
they can contaminate and overtake other cell cultures. This is related to
the fact that Henrietta Lacks had syphilis which results in an aggressive
growth of cancer due to a weakenedimmune system. And in 2013, it was
shown that the scrambled HPV genome inserted itself near thec-myc
proto-oncogenein Henrietta’s genome, causing its constitutive
expression and the rapid replication of HeLa cells in her body.

20. Thank you….