stem cells used to reverse paralysis

8/8/2019 Stem Cells Used to Reverse Paralysis

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STEM CELLS

USED TOREVERSE

PARALYSIS

Guide: K. Krishnakumar presented by

Co-guide: Ashna R Hari.S

Roll No: 3

BT-7



WHAT ARE STEM

CELLS?

Stem cells are the raw materials from

which all of the body¶s mature,

differentiated cells are made.

Stem cells give rise to brain cells, nerve

cells, heart cells, pancreatic cells, etc.



W HAT¶S SO SPECIAL

ABOUT STEM CELLS?

Have the potential to replace cell tissuethat has been damaged or destroyed by

severe illnesses.

They can replicate themselves over andover for a very long time.

Understanding how stem cells developinto healthy and diseased cells will assistthe search for cures.



T YPES

Embryonic or pluripotent stem cells are

capable of developing into all the cell

types of the body.

Adult stem cells are less versatile and

more difficult to identify, isolate, andpurify.



EMBRYONIC STEM CELLS

R esearchers extract stem cells from a 5R esearchers extract stem cells from a 5--7 days old7 days old

blastocystblastocyst..

Stem cells can divide in culture to form more of Stem cells can divide in culture to form more of

their own kind, creating stem cell line.their own kind, creating stem cell line.



SOURCES OF

EMBRYONIC STEM

CELLS

Excess fertilized eggs from IVF (in-vitro

fertilization) clinics

Therapeutic cloning (somatic cell

nuclear transfer)



STEM CELLS USED TO

REVERSE PARALYSIS Stem cells from the lining of the spinal

cord, called ependymal stem cells,

reverses paralysis.Shown that population of these cells

after spinal cord injury was many times

greater than comparable cells fromhealthy animal subjects.

The results open a new window on

spinal cord regenerative strategies.



Spinal cord injury is a major cause of paralysis.

About 1.3 million people in the United Statesare estimated to live with these injuries.

These are caused by vehicle crashes and falls.

Most of those injured are males.



STEM CELL TEST

scientists first used chemicals to tell the

embryonic mice stem cells to become

motor neurons.

The mouse stem cells spent 3.5 daysgrowing into motor neurons in the lab.

Then, researchers transplanted them into

the spinal cords of 120 injured adult rats

with paralyzed hind legs.



scientists also created a key test group of

15 paralyzed rats which got a deluxe stem

cell package.

Chemical pretreatment of the stem cells to

help new motor neurons survive.

Chemicals to help the rats' bodies accept

the stem cells.

Chemicals that told the stem cells where to

park to help one of the rats' hind pawsFor comparison, the other rats got few or

none of these additives with their stem

cells.



PARTIAL REVERSAL OF

PARALYSIS

6 months later, 11 of the 15 rats in the key

test group could put weight on the

paralyzed hind paw.

None of the other rats in the study could

do that.

But there was only partial paralysisrecovery as the rats could not move non-

target hind paws.



R ats in the key test group made 125 new

nerve connections to muscle, 50 of whichreached and worked in the targeted hind

paws.

The other rats had similar numbers of surviving, transplant-derived motor

neurons.

But without the full package of chemical

perks, those motor neurons didn't bring

paralysis recovery.



REGENERATIVE

MECHANISM

The regenerative mechanism was activated when

a lesion formed in the injured area.

The stem cells were found to have a more

effective ability to differentiate into

oligodendrocytes and other cell types.

Previous attempts were based on spinal cord-

derived stem cells from either foetal or healthy

adult donors.

These efforts reported only modest or no

significant functional improvement soon after

transplantation.



HUMAN POTENTIAL

The presence of these stem cells in the adulthuman spinal cords suggests that stem cell-

associated mechanisms might be exploited to

repair human spinal cord injuries.

Given the serious social and health problems

presented by diseases and accidents that destroy

neuronal function, there is an ever-increasinginterest in determining whether adult stem cells

might be utilized as a basis of regenerative

therapies.



REFERENCES

www.lifescience.com

www.sciencedaily.com

www.stemcellsportal.com



THANKYOU

stem cells used to reverse paralysis

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