Stem cells

1
Stem cells
Stem cells are generic cells that develop into
particular types of cells.
So they may become nerve cells, muscle cells,
blood cells in fact, any cell in the
body! Stem cells divide over and over to
produce new cells.
2
Stem cells, bone marrow and blood cells
One of the main places you find stem cells is in
bone marrow. Stem cells in bone marrow produce
new blood cells to replace those that have
died. When the cells are mature they are
released into the bloodstream. A bone marrow
donation is really a donation of stem cells.
Bone marrow is found in the cavities inside the
long and flat bones of the body.
3
Leukaemia

• Leukaemia is a form of cancer.
• In the most common forms of leukaemia, one
  abnormal white blood cell continuously replicates
  (clones) itself.
• These abnormal white blood cells do not function
  properly
• They do not fight infections
• They inhibit the production of other blood cells
  and platelets
• For some people, a bone marrow transplant can
• be a life-saver.

4
Transplants save lives

• Bone marrow transplants not only save the lives
  of leukaemia patients.
• They can also save the lives of those suffering
  from
• illnesses where the immune system does not
  function properly such as aplastic anaemia
  (where the bone marrow stops making enough blood
  cells)
• rare genetic diseases such as osteopetrosis
  (where bones harden and become dense and bone
  marrow does not develop properly)
• all kinds of cancers(where healthy stem cells
  have been damaged during treatments to destroy
  cancer cells)

5
Stem cell (bone marrow) donation

• There are three ways to collect stem cells from a
  donor
• Bone marrow A donor has a small operation under
  general anesthetic.
• Circulating bloodA donors circulating stem
  cells are boosted with a special drug. Then they
  are connected to a cell separator machine, which
  collects the stem cells and returns the rest of
  the blood to the donor.
• Cord bloodSelected hospitals offer new mothers
  the chance to donate the blood that remains in
  the placenta and umbilical cord after their
  babys birth.

6
Advantages / disadvantages for patients

• Advantages
• Cord blood
• hasnt been exposed to environment so less likely
  to contain viral infection
• requires less stringent matching
• once collected is banked and can be readily
  available at short notice.
• Bone marrow and circulating blood
• tend to have a greater number of stem cells in
  the donation, so tend to be accepted into the
  patients body more quickly.
• Disadvantages
• Cord blood
• tends to have less stem cells in the donation.
• Bone marrow and circulating blood
• finding a match and arranging a donation can take
  weeks, or months (this is time the patient may
  not have).

7
Finding a match

• A bone marrow donor needs to be a close tissue
  type match with the recipient
• You can tell what someones tissue type by
  testing their blood
• Tissue type is inherited but only 30 of donors
  are found from within a patients family
• Patients are most likely to find a match from
  within their own ethnic community
• So donors from all ethnic backgrounds are needed