Stem Cells Flashcards
What are Stem Cells?
Unspecialised cells that have the ability to self-renew and divide to replenish lost cells without limit.
Potential to develop into many different cell types in the body, during early life and growth
Under the right conditions in the body or a laboratory, stem cells divide to form more cells called daughter cells.
What can happen when stem cells divide?
When they replicate, it produce two stem cells that has the potential either to remain a stem cell or become another type of cell with a more specialised function, eg. muscle cell, red blood cell
State an important characteristic, that distinguish it from other cell types?
Unspecialised cells capable of renewing themselves through cell division
Only under certain physiologic or experimental conditions
Give examples to why replication occurs only under certain physiologic or experimental conditions. (Bone marrow/Gut and pancreas/heart
Gut and bone marrow, etc
Stem cells regularly divide to repair and replace worn out or damaged tissue
Pancreas and heart etc..
divide under special conditions
What are the 4 types stem cells?
Somatic (Adult stem cell)
Embryonic
Umbilical
Peripheral blood
What are somatic stem cells?
Exist naturally in the body
It is important for growth, healing, replacing cells that are lost through daily war and tear
Produce all different cell types that make up our blood
What can somatic stem cells be used for? (2) advantage/disadvantage
Stem cells from the blood and bone marrow are routinely used as a treatment for blood related diseases.
Natural circumstances, they become only a subset of related cell types. Partial differentiation can be an advantage when you want to produce blood cells. A disadvantage is the inability to producing an unrelated cell type
What are 3 special conditions for Somatic stem cells?
Present in low abundance and are difficult to isolate and grow in culture.
Isolation of some types could cause considerable tissue or organ damage, as in the heart or brain.
Somatic stem cells can be transplanted from donor to patient, but without drugs that suppress the immune system, a patient’s immune system will recognise transplanted cells as foreign and attack them.
What are the ethical considerations with somatic stem cells?
Therapy involving somatic stem cells is not controversial; however, it is subject to the same ethical considerations that apply to all medical procedures.
What are Embryonic stem cells?
Formed as a normal part of embryonic development. They can be isolated from an early embryo and grown in a dish.
What is the potential of Embryonic stem cells?
potential to become any type of cell in the body, making them a promising source of cells for treating many diseases.
What is a special considerations for Embryonic stem cells?
Without drugs that suppress the immune system, a patient’s immune system will recognise transplanted cells as foreign and attack them.
What is a ethical considerations with Embryonic stem cells?
isolate human embryonic stem (hES) cells in the lab, they destroy an embryo
What are the 5 special steps for iPS stem cell differentiation in medical treatment. I T W P D
Isolate Treat Wait Pluripotent Differentiate
Describe the 1st step of iPS stem cell differentiation in medical treatment. (I)
Isolate cells from patient (skin or fibroblasts) grown in a dish
Describe the 2nd step of iPS stem cell differentiation in medical treatment. (T)
Treat cells with ‘reprogramming’ factors
Describe the 3rd step of iPS stem cell differentiation in medical treatment. (W)
Wait a few weeks
Describe the 4th step of iPS stem cell differentiation in medical treatment. (P)
Pluripotent stem cells
Describe the 5th step of iPS stem cell differentiation in medical treatment. (D)
Change culture conditions to stimulate cells to differentiate into a variety of cell types
What are four difficult questions raised for Embryonic stem cells?
Does life begin at fertilisation, in the womb, or at birth?
Is a human embryo equivalent to a human child?
Does a human embryo have any rights?
Might the destruction of a single embryo be justified if it provides a cure for a countless number of patients?
Since ES cells can grow indefinitely in a dish and can, in theory, still grow into a human being, is the embryo really destroyed?
What are iPS stem cells (Induced Pluripotent Stem Cells)?
created artificially in the lab by “reprogramming” a patient’s own cells. iPS cells can be made from readily available cells including fat, skin, and fibroblasts (cells that produce connective tissue).
What can iPS stem cells do?
become any cell in the body
iPS cells can be made from a patient’s own cells, there is no danger that their immune system will reject them.
What are 2 special conditions for iPS stem cells treatment?
much less expensive to create than ES cells generated through therapeutic cloning
“reprogramming” process introduces genetic modifications, the safety of using iPS cells in patients is uncertain.