Adult Stem Cell & Stem Cell Therapies Flashcards
(31 cards)
Do stem cells exist in adult organisms?
Yes, adult stem cells exist in various tissues including bone marrow, intestine, and hair follicles.
Adult stem cells play a crucial role in the regeneration and repair of tissues.
Which cells and/or tissues are constantly being replaced?
Blood lineages, including erythrocytes and white blood cells.
Erythrocytes are produced at a rate of approximately 2 million per second.
What is the function of erythrocytes?
Transport oxygen.
Erythrocytes have a lifespan of about 120 days.
What is the innate immune system?
A non-specific immune response that combats infection.
It includes cells like neutrophils, eosinophils, basophils, and macrophages.
What is the adaptive immune system?
A highly specific immune response that confers long-lasting immunity.
It evolved in jawed vertebrates and involves B and T cells.
What is the lifespan of a neutrophil?
1-2 days.
Neutrophils are involved in the acute phase of inflammation.
What is the function of T cells?
Destroy virally infected cells and tumor cells.
Memory T cells persist long-term and are antigen-specific.
What are the two types of stem cells mentioned?
Adult stem cells and progenitor cells.
Adult stem cells have indefinite self-renewal and differentiation potential.
How were hematopoietic stem cells first identified?
Through functional assays involving transplantation into lethally irradiated mice.
This method resulted in long-term repopulation of all blood lineages.
What is aplastic anemia?
A decrease in blood counts.
It can be caused by radiation effects, leading to symptoms such as nausea and hair loss.
What are the effects of radiation on humans?
Loss of hair, nausea, vomiting, and diarrhea.
These effects are due to damage to rapidly dividing cells.
What is the role of intestinal stem cells (ISCs)?
Regeneration of the intestinal epithelium.
ISCs are located in the crypts of the intestine.
What is the significance of the CCR5 gene in HIV?
Mutations in CCR5 can provide resistance to HIV infection.
Scientists are exploring gene editing of CCR5 to treat HIV patients.
What is limbal stem-cell therapy?
A treatment that uses adult stem cells to replenish the cornea.
It has been used in the long-term regeneration of corneal tissue.
What disease is associated with mutations in extracellular matrix proteins?
Junctional Epidermolysis Bullosa.
This disease affects the integrity of the skin and can be treated with stem cell therapies.
What is the role of retinal pigment epithelium (RPE)?
Provides support to overlying photoreceptors in the eye.
RPE is crucial for vision and is targeted in therapies for age-related macular degeneration.
What diseases can be treated with neural stem cells?
Neurodegenerative diseases, retinal degeneration, and demyelination diseases.
Neural stem cells give rise to both neurons and glial cells.
What is the function of oligodendrocytes?
To lay down myelin in the central nervous system.
Myelin increases the speed of neural transmissions.
What breakthrough was achieved regarding Type 1 diabetes?
Human embryonic stem cells can be coaxed to produce insulin-producing beta-cells.
This can potentially lead to transplants for diabetes patients.
What is the outcome of combining gene therapy with HSC transplantation?
It can cure diseases if treated early enough.
This approach has shown promise in conditions like metachromatic leukodystrophy.
Who worked on frog embryos before shifting focus to mammalian pluripotent stem cells?
John Gurdon
What special interest did John Gurdon have in stem cell research?
Finding ways to use stem cells to cure diabetes
Where do adult stem cells exist in the body?
- Bone marrow (for blood)
- Intestine (bottom of the crypts)
- Hair follicles (bulge)
What tissues are affected by radiation and chemotherapy?
Tissues that turn over quickly, such as blood, gut and hair
