Embryonic Stem Cells & Cloning Fiona Cunningham

Embryonic stem cells New hope for patients with Parkinson or Alzheimer disease? Potentially - an unlimited source of cells, tissues and organs for transplants and cell therapy

What are embryonic stem cells? Derived from the inner cell mass of a 1-week-old embryo (blastocyst) Unlimited, prolonged self- renewal Can divide and differentiate into any type of body cell

Embryonic stem cells Can be driven down different differentiation pathways in a controlled way in culture We don’t yet know the different signals that control this Most research done to date has been on mouse ES cells But mouse & human ES cells do not respond in the same way

Uses of ES cell line Screening of drugs that may cause birth defects Discovery & study of rare human proteins Study of early human development Gene therapy vector For transplantation of tissues –still problem with rejection from patient

Overcoming rejection Banking of many ES cell lines representing MHC alleles - –will increase probability of finding a tissue match Genetic modification of ES cell line so ‘immunologically naked’ FCombining cloning & ES cell technologies

Cloning Cloning: producing a genetically identical copy gene, cell, tissue, organism Reproductive cloning vs therapeutic cloning Nuclear transfer technology Dolly

Nuclear transfer

Human application ES cell lines: tissue for transplantation

Why the controversy? Deriving stem cells from embryos destroys them!

In Australia Destructive embryo research is prohibited in Vic and WA Human cloning is prohibited in Vic, WA, SA (& possibly NSW)

In US Reproductive cloning has only recently been prohibited (August 2001) Research using stem cells is permitted and will now be govt as well as privately funded Private companies hope to ‘cash in’ –Geron Corporation + Roslin Bio-Med –American Cell Technology (ACT)

Are there alternatives? Adult stem cells Human-animal chimera fusion of human DNA from a somatic cell with enucleated animal eggs Change legislation exempt research on ES cell lines from bans on embryo research (ES cells  embryos) De-differentiation of somatic cells to transform into ES cells??

In the future …. Jenny (2 years old) has leukaemia. She needs a bone marrow transplant within 2 years. No donor found. We could clone Jenny - create an embryo then remove ES cells from the embryo to generate compatible bone marrow.

4. Fused cell develops to blastocyst stage. New embryo develops from inner cell mass 2. Nucleus removed from donor egg. 6. Bone marrow cells transplanted into Jenny. 5. Cells removed from inner cell mass. Directed to develop into bone marrow tissue 3. Jenny’s cell and enucleated egg fused. 1. Healthy cell removed from Jenny.

Should Jenny be cloned? Consider this from the points of view of: a) Jenny’s parents b) Jenny’s doctor c) Jenny herself d) the cloned embryo e) Jenny’s family minister f) the Minister for Health (federal) g) a ‘right-to-life’ activist h) Jenny’s brother (5 years older)