Presentation on theme: "Prepared by the AUSTRALIAN STEM CELL CENTRE Introduction to Stem Cells."— Presentation transcript:
Prepared by the AUSTRALIAN STEM CELL CENTRE Introduction to Stem Cells
What are stem cells? the body is made up of about 200 different kinds of specialised cells such as muscle cells, nerve cells, fat cells and skin cells all cells in the body come from stem cells a stem cell is a cell that is not yet specialised the process of specialisation is called differentiation once the differentiation pathway of a stem cell has been decided, it can no longer become another type of cell on its own
Stem cells can: self-renew to make more stem cells differentiate into a specialised cell type Embryonic stem cells (pluripotent) Stem cells that can become many types of cells in the body are called pluripotent Tissue stem cells (multipotent) Stem cells that can become only a few types of cells are called multipotent Why are stem cells special?
Tissue stem cells often known as adult stem cells also includes stem cells isolated from fetal and cord blood reside in most tissues of the body where they are involved in repair and replacement generally very difficult to isolate already used to treat patients (haematological malignancies, diseases of the immune system) Bone marrow Kidney Lung
8-cellblastocyst fertilised egg 2-cell egg Day 0 Day 1 Day 2 Day 3 Day 6 Donated excess IVF embryos Images from Where do embryonic stem cells come from? Inner cell mass
Embryonic stem cells derived from donated IVF embryos can be grown indefinitely in the laboratory in an unspecialised state retain ability to specialise into many different tissue types – know as pluripotent can restore function in animal models following transplantation Human embryonic stem cells can become any cell in the body including these beating heart cells human embryonic stem cells
What about cloning? Has that got anything to do with stem cell research? Dolly the Sheep Reproductive Cloning Somatic Cell Nuclear Transfer – cloning to make stem cells (therapeutic cloning) Snuppy the Puppy Human cloning is banned in Australia and many countries around the world.
Induced pluripotent stem cells derived from adult cells in very recent discovery! can be grown indefinitely in culture in an undifferentiated state similar properties to embryonic stem cells as can differentiate into many different tissue types – pluripotent can create stem cells directly from a patient for research Induced change in gene expression pluripotent stem cells Starting cells from donor tissue iPS Cells
Using stem cells to conduct medical research and treat disease is acceptable? Dont know No Yes 3% 5% 92*% Biotechnology Australia – Community Attitudes to Biotechnology (2007) * Compares to 80% in 2005 survey But which type of stem cells? - pluripotent stem cells (embryonic, SCNT, iPS stem cells) - tissue stem cells (foetal, cord, adult)
Do you approve of the extraction of stem cells from human embryos for medical research? Dont know No Yes Roy Morgan Poll (2006) 5% 13% 82%
Areas of community concern –How come there are excess IVF embryos? –Why do the embryos have to be destroyed for stem cell research? Isnt this the same as taking a life? –Wouldnt it be better to donate the excess IVF embryos to other infertile couples? –Could women be forced to sell eggs or embryos for research? –Wont doing therapeutic cloning lead to cloning humans? –Why do we need to keep using embryos in research when we have new iPS cells? Australia has clear rules that allow embryos to be used in research under strict conditions. All research whether it involved embryonic, adult, cord, fetal, iPS stem cells must have special ethics approval before research can start.
What makes stem cells so valuable? Modified from Keller & Snodgrass, Nat Med 1999 Cell Therapy Research New Drugs Pluripotent stem cells Tissue stem cells No one stem cell type fits all applications. Research must continue using all types of stem cells.
Direct marketing to patients promising instant results for incurable diseases Stem Cell Tourism A growing concern to the stem cell community