Download Stem Cell Biology

In The Name of God
Stem Cell Biology Basics
Nozad H.
Stem cell workshop
Stem cell Research center
Tabriz medical university
Stem Cell Characteristics
1. ‘Blank cells’ (unspecialized)
2.Capable of dividing and renewing themselves
for long periods of time
(proliferation and self renewal)
3. Have the potential to give rise to specialized
cell types (differentiation)
4. Plasticity and Cell based therapies
5. Very low percentage available(0.01-0.03%)
Basement membrane
Extracellular matrix and
Cytokines
Cell-cell interactions
Niche , Selfrenew and Diffrentation relationship
Stem cell Self renew and Diffrentation pasibility
Stem cell division regulated by factors that control the probability of self-renewing
versus differentiative
Nature 441, 1068-1074(29 June 2006)
From stem cell to muture cells
Three important functions of stem cells
1. Plasticity: Potential to change into other cell
types
2. Homing: To travel to the site of tissue damage
1. Engraftment: To unite with other tissues
Kinds of Stem Cells
Stem cell
type
Totipotent
Description
Examples
Each cell can develop into Cells from early (1-3
a new individual
days) embryos
Pluripotent
Cells can form any (over
200) cell types
Some cells of
blastocyst (5 to 14
days)
Multipotent
Cells differentiated, but
can form a number of
other tissues
Fetal tissue, cord
blood, and adult
stem cells
This cell
Can form the
Embryo and placenta
This cell
Can just form the
embryo
Fully mature
http://www.stemcellresearch.org/testimony/20040929prentice.htm Reprinted with permission of Do No Harm.
Umbilical cord stem cells
1. Umbilical cord blood stem cell
2. Wharton’s Jelly
Specifity:
1. Easy to reach and not expensive
2. NO immune sytem reactivity(no GVHD)
3. Proliferate fast
4. Limited number
5. The mature derived cells are not fully functional
Hematopoietic stem cell
Neural stem cell
Intestine stem cell
Mesenchymal stem cell
Inducing a "forced" expression of
specific genes(Oct3/4, Sox2, Klf4 and cMyc) in somatic cells
Potential Uses of Stem Cells
1. Basic research
A. understanding the complex events and molecular
basis of during development and cancer
B. Molecular mechanisms for gene control
C. Role of signals in gene expression & differentiation
of the stem cell
D. Stem cell theory of cancer
Potential Uses of Stem Cells
2. Biotechnology(drug discovery & development)
A. Stem cells can provide specific cell types to test
new drugs.
B. Safety testing of new drugs on differentiated cell
lines
C. Screening of potential drugs(anti-tumor drugs)
D. Pluripotent stem cells would allow drug testing
in a wider range of cell types & to reduce animal
testing
Potential Uses of Stem Cells
3. Cell based therapies
A. Regenerative therapy to treat
Parkinson’s, Alzheimer’s
spinal cord injury, stroke
severe burns, heart disease, diabetes,
osteoarthritis, and rheumatoid arthritis
B. Stem cells in gene therapy
C. Stem cells in therapeutic cloning
D. Stem cells in cancer
Then
How we can Identify the Stemcells?