Download Introduction 1. Definition 1.1 Stem cells are those cells which are

Introduction
1. Definition
1.1 Stem cells are those cells which are capable of dividing and renewing themselves for long period,
unspecialized and capable of giving rise to specialized cell types.
Comment: use the term differentiating into rather than giving rise to
You might want to rephrase it as : stem cells are cells that are capable of renewing themselves
through numerous cycles of cell division while maintaining their undifferentiated state and have a
capacity to develop or differentiate into almost any specialized cell types under certain conditions.
Remember that self renewal and potency (capacity to differentiate into specialized cell types) are
the two main properties of stem cells.
1.2 Embryonic stem cells are cell that derived from the inner cell mass of the blastocyte and are
capable of differentiating into all germ layers (endoderm, mesoderm and ectoderm) and the
germline but not extra embryonic tissues.
1.3 Self renewal is ability of cells to divide themselves by maintaining their structure and functional.
Comment: Self renewal is the property of stem cells to go through numerous cycles of cell division
while maintaining their undifferentiated state.
1.4 Potency is the number and type of differentiated cell types the stem cells can become.
Comment: Potency is the capacity to differentiate into specialized cell types----that’s why there are
so many terms; totipotency, pluripotency and so on.
2. Application of stem cells in regenerative medicine (Suggestion: point out to the audience why
stem cells are very important---they can provide a ‘cure’ to certain diseases)
2.1 Bone marrow transplant for leukemia, chemotherapy, and autoimmune diseases
2.2 Regenerating pancreatic islet cells for diabetes.
2.3 Repairing nervous system for congenital disorders, degenerative diseases and nerve injuries from
stroke or trauma
2.4 Repairing cardiac muscle for heart disease
Suggestion: You might want to give a transition here from the application of stem cells to the next
slide of ES vs. iPS. For example, ethical issue associated with how to obtain ES that drives the
scientist to investigate the alternative which is to turn differentiated cells back to their so-called
stem cell state---meaning that the cells still have the self renewal and potency properties.
3. Embryonic stem cells vs. induced pluripotent stem cells
3.1 Embryonic stem cells are cells which derived from a group of cells called the inner cell mass,
which is part of an early embryo (blastocyst) before implantation occurs.
3.2 Induced pluripotent stem cells (iPSCs) are adult cells that undergone de-differentiate into a
pluripotent embryonic stem cell-like state.
Comment: iPS are adult cells that have been genetically reprogrammed to an embryonic stem cell–
like state by being forced to express genes and factors important for maintaining the defining
properties of embryonic stem cells.
Objective of the paper
1. Compare similarities and difference between embryonic stem cells and iPS cells
2. Mechanism of iPS cell reprogramming
3. Clinical application
Body
1. This paper provides the basic information about pluripotent stem cells and how scientists
convert somatic cells into pluripotent cells.
2. There are 4 techniques applied to induce the pluripotent stem cells which are
2.1 Nuclear transfer
2.2 Cell fusion
2.3 Direct reprogramming
2.4 Cell culture
Suggestion: For nuclear transfer, you can give an example of dolly the sheep that was the
first animal being cloned from adult somatic cell by nuclear transfer technique. That
particular experiment shows that genes in the nucleus of differentiated somatic cell are still
capable of reverting back to an embryonic state, thus creating a cell that can then go on to
develop into any part of an animal.
Point out that direct reprogramming is the iPS that you are going to talk about in this
presentation
3. Comparison between iPS and ES cells base on
3.1 Genome
3.2 Transcriptome
3.3 Epigenome
3.4 Developmental potential
Suggestion: Make sure you know the definition of transcriptome and epigenome. For
transcriptome, highlight those four genes that are the main players in the reprogramming of
iPS. Think about how you want to present it---for example iPS and ES on the columns and
those 4 categories on the rows, so it will be easy to follow.
The details given in epigenome section are quite complicated. The most details you want to
go down to is just to distinguish the loss of DNA methylation that is associated with stem-like
cell.
4. Mechanism of reprogramming, which was summarized according to each species of
reprogramming factors;
4.1 Oct4
4.2 Sox2
4.3 c-Myc
4.4 Klf4
4.5 Nanog
4.6 Lin-28
Suggestions: You can simply say what are they and what are their main functions.
5. The paper mentioned about clinical applications of iPS cells that it could be done by
combination of direct reprogramming and gene targeting.
6. Issues that have to be addressed before iPS cells could be used in broader clinical
applications
Conclusion