Stem Stem CellsCells

http://www.dnalc.org/resources/animations/stemcells.html

ObjectivesObjectives

What are stem cells?What are stem cells?

What are the different types and where do What are the different types and where do they come from?they come from?

What are the potential new medical What are the potential new medical treatments using stem cells?treatments using stem cells?

What research is needed to make such What research is needed to make such treatments a reality?treatments a reality?

What are stem cells?What are stem cells?

Remarkable potential to develop into Remarkable potential to develop into different cell typesdifferent cell types

As each new cell divides it has potential to As each new cell divides it has potential to remain a stem cell or another specialized remain a stem cell or another specialized cell like muscle, RBC or brain cell.cell like muscle, RBC or brain cell.

May serve as an internal repair system: May serve as an internal repair system: Divide without limit Divide without limit

Different from other cell typesDifferent from other cell types

1.1. They are unspecialized cells They are unspecialized cells capable of renewing themselves capable of renewing themselves thru cell divisionthru cell division

2.2. They can be induced to become They can be induced to become tissue or organ-specific with special tissue or organ-specific with special fxnsfxns

Types of Stem CellsTypes of Stem Cells Embryonic stem Embryonic stem

cellscells Somatic or Somatic or

adult stem cellsadult stem cells 2006, induced 2006, induced

pluripotent pluripotent stem cellsstem cells

Embryonic stem cellsEmbryonic stem cells

Pluripotent: capacity to become ANY Pluripotent: capacity to become ANY cellcell

Grow easy in cultureGrow easy in culture Large numbers are easily harvested Large numbers are easily harvested

IPSCsIPSCs

First human cells introduced in lab in First human cells introduced in lab in 20072007

Genetically reprogrammed to an Genetically reprogrammed to an embryonic stem cell like state by embryonic stem cell like state by being forced to express genesbeing forced to express genes

Demonstrate the ability to be Demonstrate the ability to be pluripotentpluripotent

Adult Stem CellsAdult Stem Cells Found in brain, bone marrow, blood, skeletal Found in brain, bone marrow, blood, skeletal

muscle, skin, heart, liver, ovaries and testismuscle, skin, heart, liver, ovaries and testis

Once removed from body, Capacity to divide is Once removed from body, Capacity to divide is limitedlimited

Trying to figure out how to regenerate in large Trying to figure out how to regenerate in large quantities to usequantities to use

Rare in mature tissueRare in mature tissue

Not supported yet, but less likely to be rejectedNot supported yet, but less likely to be rejected

Why do we have stem cells?Why do we have stem cells?

Blastocyst : inner cells give rise to Blastocyst : inner cells give rise to entire bodyentire body

Bone marrow: generate Bone marrow: generate replacements for cells that are lost replacements for cells that are lost thru injury, disease or normal wear thru injury, disease or normal wear and tear.and tear.

What is the potential new medical What is the potential new medical treatments using stem cells?treatments using stem cells?

Offer potentials for treating diseases Offer potentials for treating diseases like diabetes, heart disease, like diabetes, heart disease, Parkinson’s and Alzheimer's Parkinson’s and Alzheimer's

Screen new drugsScreen new drugs

Develop model systems to study Develop model systems to study normal growth and id causes of birth normal growth and id causes of birth defects.defects.

A new treatment strategy that specifically targets cancer stem cells, when combined with current treatments, may lead to a more complete and durable regression of malignant cancers.

Continues to advance knowledge Continues to advance knowledge about how an organism develops about how an organism develops from a single cell and how healthy from a single cell and how healthy cells replace damaged cellscells replace damaged cells

What research is needed to make What research is needed to make such treatments a reality?such treatments a reality?

Number and type of adult stem cells Number and type of adult stem cells that exist. What tissues containthat exist. What tissues contain

How they evolve during developmentHow they evolve during development How do stem cells remain in How do stem cells remain in

undifferentiated state, but other cells undifferentiated state, but other cells around them are differentiated?around them are differentiated?

Donor specificityDonor specificity Factors that stimulate stem cells to Factors that stimulate stem cells to

relocate to sites of injury?relocate to sites of injury?

If you had in vitro fertilization perform If you had in vitro fertilization perform and as a result have frozen embryos and as a result have frozen embryos remaining, what would you do with remaining, what would you do with them?them?

Why?Why? What do you need to know to help you What do you need to know to help you

make an informed decision?make an informed decision? Support your argument with details Support your argument with details

from the article, “Frozen Dreams”, from the article, “Frozen Dreams”, What you have learned in class and What you have learned in class and outside research you have done on outside research you have done on stem cells.stem cells.