Stem Cell

STEM CELLS SD Jacinto Bio 1 Institute of Biology UP Diliman

Stem Cells: Scientific Progress and Future Research Directions

All about stem cells Unspecialized cells Capable of renewing themselves for

long periods by cell division Under special conditions can be induced to differentiate into many types of cells with different functions (e.g. myocardiocytes, insulin producing cells) 2 types Embryonic and Adult

Important Areas of Research Why embryonic stem cells proliferate

for a year or more in the lab w/out differentiating but most adult stem cells cannot What are the factors in living organisms that normally regulate stem cell proliferation and self renewal What are the signals in mature organism causing stem cells to proliferate and remain unspecialized until http://stemcells.nih.gov/info/basics/basics3.asp the cells are needed for repair of

Important Areas of Research (cont’d) Are signals for differentiation

similar for all stem cell types Can specific signals be identified that promote differentiation into specific cell types

ESC and directed differentiation By changing chemical composition of culture

medium, alter the surface of culture dish or make transgenic cells If directed differentiation is reliable and

reproducible, ESC can be used to treat certain diseases in the future e.g. Parkinsons disease, traumatic spinal cord injury, Purkinje cells degeneration, Duchenne’s muscular dystrophy, heart disease and vision and hearing loss

http://stemcells.nih.gov/info/basics/basics3.asp

Undifferentiated embryonic stem cells

Inner cell mass of blastocyst

N2 medium/bFGF/laminin Nestin positive neuronal precursor cells Remove bFGF

Directed Differentiation Embryoid bodies

Adherent substrate

ITFSn medium (insulin trasferrin/fibronectin/selenium)

Selection of Nestin positive cells Expansion phase Differentiation phase

N2 medium/bFGF/B27 media supplement Nestin positive pancreatic progenitor cells Remove bFGFl add nicotinamide

Dopamine & serotonin Insulin secreting pancreatic secreting cells islet-like clusters Patterned after http://stemcells.nih.gov/info/basics/basics3.asp

Adult Stem Cell (ASC) research Also called somatic stem cells Undifferentiated cell found among

differentiated cells in a tissue or organ Can renew itself Can differentiate to yield major specialized

cell types of the tissue or organ 1o role is to maintain and repair Origin is unknown

Adult Stem Cell (ASC) research (cont’d) Research in mice showed that brain

has stem cells that can differentiate into connective tissue cells and neurons Plasticity was also discovered

http://stemcells.nih.gov/staticresources/info/scireport/PDFs/chapter8.pdf

Where ASC are found Brain, bone marrow, peripheral blood, blood

vessels, skeletal muscles, skin and liver ACS occur in very small number in each tissue; are quiescent for many years until they are called to duty during injury or disease

Potential Uses of SC May yield information about events

occuring during human devt May yield info on how diseases arise and may suggest new strategies for therapy Used for drug screening Generation of cells and tissues to be used for cell based therapy

: www.nih.gov/news/stemcell/ primer.htm

: easyweb.easynet.co.uk/ ~sfl/rlb_stem.htm

The Woo Suk Hwang fraud From National University of Seoul-faked

production of human cloned embryo Faked production of 11 patient tailored cell lines from embryonic clones

That’s all for now…