Strom 2 Flashcards
Describe Pluripotent Stem Cells
They are rare cells found in the bone marrow ( 1 in 20 million) They are difficult to identify clearly by morphology and express receptors for key growth factors
What two lineages do Pluripotent stem cells give rise to ?
Common Myeloid Progenitors and Common Lymphoid Progenitors
What are burst forming units and colony forming units defined by ?
Responsiveness to growth factors.
What stimulates erythropoietin production ?
Hypoxia Inducing Factor Alpha and Beta. The erythropoietin gene contains receptors for this factor and will be upregulated in conditions of hypoxia. Thus in anemiaErythropoietin production will be increased.
What does erythropoietin do ?
It will stimulate progenitor cells to undergo erythropoiesis
What kind of cell is this ?
Blast Cell which make up 3-4 % of the bone marrow
What kind of cell is this ?
Promyelocyte which is right after the band on the granulocyte lineage line
What kind of cell is this ? It is on the granulocyte lineage
Myelocyte- which can both proliferate and regenerate
What kind of cell is this ?
Meta Myelocyte, It comes after the myelocyte and before the bands and neutrophils on the granulocyte differentiation pathway
What kind of cell is this ?
This is a band and a neutrophil. Notice the band has a horse shoe shaped nucleus
What growth factor stimulates production of granulocytes ?
G-CSF which is also Filgastrum
What kind of cell is this ?
Megakaryocyte- notice the segmented polyploid nucleus
What stimulates platelet production ?
Thrombopoietin. It is thought to bind platelets and when they are absent it will bind to megakaryocytes and stimulate production of platelets
What kind of cell is this and what lineage is this a part of ?
This is a pronormoblast, notice the blue sytoplasm this is the basophilic staining of RNA and the hyperchromatin in the nucleus
What kind of cell is this ?
Basophilic Erythroblast
What kind of cell is this ?
Polychromatophillic Erythroblast
What kind of cell is this ?
Normochromatic Erythroblast which will then form RETICULOCYTES and go on to form nascent RBC’s and Mature RBC’s
Describe the difference between adult marrow and juvenile marrow
The Adult marrow will have lower cellularity and less fat cells
What are the 4 requirements of red blood cell production ?
- Heme Synthesis
- Globulin Synthesis
- DNA Synthesis
- Regulation
Describe Heme Synthesis, Where does it take place, and what is an essential cofactor ?
Heme Synthesis takes place in the mitochondria and the rate limiting step is the condensation of glycine and succinyl CoA under the action of the key rate limiting enzyme ALA.
Vitamin B6 is a cofactor for the rate limiting enzyme
What are the requirements for globin synthesis ?
Alpha and Beta Globin Genes
In Hematopoiesis what is essential to making DNA ?
Thymidine which requires B12 and Folate
What are the three components that you should be able to identify in mature marrow ?
Myeloid
Erythroid
Megakaryocytes
What molecule regulates hematopoiesis ?
Erythropoietin which requires normal kidneys and normal stromal microenvironment