Introduction to Stem Cells

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Introduction to Stem Cells
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What is a stem cell?

• Master cell.
• Undifferentiated (unspecialised cell type).
• Found in all multicellular organisms.
• Self-renewing and can differentiate.
• Can you give examples of differentiated cells
  and their functions?

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Embryonic stem cells

• Totipotent
• toti total
• potent capacity
• The state of the cells after the first few
  divisions of the fertilised egg.
• Have the capacity to become all cell types plus
  placenta.

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Embryonic stem cells

• Pluripotent
• pluri many
• potent capacity
• At blastocyst stage cells become pluripotent.
• Have the capacity to become all cell types but
  not placenta.
• Cells of most interest to research scientists.

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Adult stem cells

• Multipotent
• Can develop into cells that are closely related.
• Limited number of several cell types.
• Make all cell types from the tissue they come
  from.
• Found in many parts of the body.
• Can self-renew over a lifetime.

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Focus questions

• What is the unique property of stem cells which
  makes them different from a specialised cell?

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Focus questions

• What does it mean when we say a cell has become
  differentiated?

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Focus questions

• Embryonic stem cells are described as pluripotent
  whereas adult stem cells are multipotent.
  Describe in your own words what these terms mean.

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Focus questions

• Why does adult tissue need stem cells?

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Focus questions

• Why are research scientists so interested in
  using stem cells?

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Focus questions

• We have discussed several types of stem cells.
  Which type do you think would be most useful to
  treat human disease? Give a reason for your
  answer.

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Focus questions

• Each group has to investigate a disease that
  could be treated with stem cells. For the disease
  the group has identified
• describe the condition
• identify the organ/system affected
• give a reason for why stem cells rather
• than drug therapy would be beneficial.