Hematopoietic Stem Cells And Hematopoiesis Flashcards
Two fundamental properties of homeopoetic stem cells
- Multi-lineage differentiation
2. Self-renewal
Sources of hematopoietic stem cells
- Autologous
- Syngenic
- Allogenic
- Haploidentical
Properties of hematopoietic stem cells
- Undifferentiated
- Relatively quiescent
- Asymmetric division
How are hematopoietic stem cells undifferentiated
Do not express mature markers
Asymmetric division of hematopoietic stem cells
Generate one daughter cell that differentiated and one that self-renews
Only the hematopoietic stem cells can self-renew
Yep
Disease of aberrant proliferation
Cancer
One way to protect against cancer is to _________ to a small compartment of progenitors
Limit self-renewal
How long does it take to make a granulocyte from stem cells?
About 21 days
Act on progenitors to control blood cell production
Myeloid cytokines
Epo is a true
Hormone
Myeloid growth factors act through cell surface receptors triggering
Dimerization and activation of cell kinases
Blood cell development takes place
Within a highly specialized bone marrow micro environment ( bone or sinusoid lumen)
Clinical use of hematopoietic growth factors:
Epo
- anemia of chronic kidney failure
- chemo-induced anemia
Clinical use of hematopoietic growth factors:
Thrombopoietin
- ITP
- chemo-induced thrombocytopenia
Clinical use of hematopoietic growth factors:
Granulocyte colony-stimulating factor
- chemo- induced neutropenia
- aplastic anemia
Clinical use of hematopoietic growth factors:
Granuclocyte
- chemo-induced neutropenia
pancytopenia
low blood count
anemia
low RBC
leukopenia
low WBC
thrombocytopenia
low platelets
progenitor cells more common than HSC?
yep
morphologically distinct blood cells are produced only at the _______ stages of differentiation
terminal
lifespan of a neutrophil
> 12 hr
Erythropoietin and IL3 act on progenitors in the _________ lineage, and thrombopoietin and IL6 act on the ___________ lineage.
Erythropoietin and IL3 act on progenitors in the red cell lineage, and thrombopoietin and IL6 act on the megakaryocyte lineage.
The aim of a hematopoietic stem cell transplant is to replace the hematopoietic system of the recipient. The only way to maintain the new hematopoietic system long-term is with cells that have long-term repopulating and self-renewal capability. Which is it?
Only the hematopoietic stem cell, which carries the surface marker antigen CD34, has this capability.
is a disorder of granulopoiesis characterized by 21-day oscillations in the number of circulating neutrophils, usually due to a mutation in the gene for neutrophil elastase.
Cyclic neutropenia
treatment for cyclic neutropenia
ngoing treatment with G-CSF does not prevent the cyclical fluctuation in the neutrophils count but does raise the baseline neutrophil count enough so that recurrent infections are prevented.
