INTRODUCTION TO STEM CELL TECHNOLOGY

I. What are Stem Cells

1. Stem cells differ from other kinds of cells in the body.

2. All stem cells regardless of their source have three general properites.

a. Capable of dividing and renewing themselves for long periods.

b. They are unspecialized. c. They can give rise to specialized cell types.

II. Types of Stem CellsA. Two main types of Stem Cells

1. Pluripotent Stem Cellsa. Embryonic Stem Cellsb. Induced Pluripotent Stem Cells.

2. Adult or Multipotent Stem Cellsa. Mesenchymal, Neural, Hematopoietic , and Cancer Stem Cells

B. Embryonic Stem Cells1. Derived from the blastocyte of a 5 day old embryo.

(The blastocyst is a structure formed in the early development of mammals. It possesses an inner cell mass (ICM) which subsequently forms the embryo.)

2. Are pluripotent (**They can differentiate into almost any cell type in the body!!!)

3. Can renew themselves indefinitely.

EMBRYONIC STEM CELLS

C. Induced Pluripotent Stem Cells(iPSC’s)1. Generated from reprogrammed somatic cells.2. Similar or equivalent to ESC’s; they are also

pluripotent and the ability to renew themselves indefinitely.

D. Adult Stem Cells (ex. MSCs, NSCs, ADSCs)1. Isolated from adult tissues, organs or blood,

umbilical cord blood, etc. 2. Are multipotent- They can give rise to a number

of RELATED cell types.3. Can renew themselves a number of times but

NOT INDEFINITELY. **We will discuss the examples later in the notes!!!

II. Embryonic Stem Cells

A. Embryonic Stem Cell 1. Derived from the inner cell mass (ICM) fo the

blastocyte, an early-stage embryo. 2. ESCs are able to differentiate into all derivatives

of the three primary germ layers which include each of the more than 220 cell types in the adult body.

3. Have a broad application base in basic research, drug discovery, and cell therapy.

**Three primary germ layers of cells!

Do some RESEARCH!!

• In January 2009, Phase I clinical trials for transplantation of oligodendrocytes derived from human Embryonic Stem cells into spinal cord-injured individuals receiving approval from the FDA, marking it the worlds first ES cell human trial.

• Go online and see if you can find any information on the latest Embryonic Stem Cell (ESC) clinical trials!!!!!

III. Induced Pluripotent Stem Cells

A. What are iPSCs?1. iPSCs 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.

2. iPSCs were first developed by Shinya Yamanaka at Kyoto University Japan in 2006

3. Yamanaka used genes that had been identified as particularly important in embryonic stem cells (ESCs) and used RETROVIRUSES to transduce mouse fibroblasts with a selection of those genes.

a. Shinya Yamanaka

IV. How are iPSCs created?

V. Why are iPSCs important???

A. iPSC cell research allows1. Both wild-type and disease specific pluripotent

cells to e derived from accessible tissue sources. B. iPSC cells will help researchers

1. Create genetic models for disease2. Understand molecular controls influencing cell

development.

V. Why are iPSCs important???

C. iPS cells hold the promise of: 1. Reducing drug development times. 2. Improving drug safety3. Bringing us closer to PERSONALIZED MEDICINE

and specific PERSONALIZED targeted therapies

VI. Adult Stem Cells

A. Mesenchymal Stem Cells (MSCs)1. Also called bone marrow stromal cells, are

MULTIPOTENT stem cells that differentiate into a variety of cell types including:

a. Osteoblasts (bone cells)b. Chondrocytes (cartilage cells)c. Adipocytes (fat cells)

VI. Adult Stem Cells

A. Mesenchymal Stem Cells (MSCs)2. Human MSCs are of interest in clinical

applications due to: a. Wide range differentiation potential. b. Immunosuppressive attributes.

3. Potential MSC Therapies. a. Crohn’s Diseaseb. Bone defects/Genetic Diseasec. Cardiac Repaird. Trachea Repair

VI. Adult Stem Cells

B. Hematopoietic Stem Cells (HSCs)1. HSCs are multipotent stem cells that give rise to all the

blood cell types. 2. The average human requires approximately one

hundred billion new hematopoietic cells each day. 3. The continued production of these cells depends

directly on the presence of HSCs, the ultimate, and only, source of all these cells.

4. HSC transplants are now routinely used to treat patients with cancers and other disorders of the blood and immune systems.

VI. Adult Stem Cells

C. Neural Stem Cells (NSCs)1. Are multipotent stem cells 2. Derived from brain tissue or differentiated from

pluripotent stem cells. 3. NSC research is currently focused on methods to

repair damage from degenerative diseases such as Parkinson’s Disease and ALS (Lou Gherig’s disease), as well as from brain and spinal cord injuries resulting from stroke or trauma.

VI. Adult Stem Cells

D. Cancer Stem Cells(CSCs)1. Found within tumors that possess characterisitics

associated with normal stem cells, specifically the ability to give rise to all cell types found in a particular cancer sample.

2. Current CSC theory states that if current treatments of cancer do not properly destroy enough CSCs the tumor will reappear.

3. Found in brain, breast, colon, ovary, pancreas, prostate, and melanoma cancer cells.

VII. SUMMARY OF STEM CELLS!

A. All stem cells-regardless of their source- have THREE general properties!

1. They are capable of dividing and renewing themselves for long periods of time.

2. They are unspecialized 3. They can then give rise to a specialized cell type.

VII. SUMMARY OF STEM CELLS!

B. There are TWO main types of Stem Cells!!!1. PLURIPOTENT STEM CELLS

a. Embryonic Stem Cells (ESCs)b. Induced Pluripotent Stem Cells (iPSCs)

2. Adult or Multipotent Stem Cellsa. Mesenchymal Stem Cells (MSCs)b. Neural Stem Cells (NSCs)c. Hematopoietic Stem Cells (HSCs)d. Cancer Stem Cells (CSCs)

VII. SUMMARY OF STEM CELLS!

C. Stem Cells have Application in: 1. Basic Research2. Drug Discovery3. Cell Therapy4. Personalizing Medicine