Lecture 13 Flashcards
List characteristics of hematopoietic stem cells.
Are pluripotent (committed to either myeloid or lymphoid stem cell lines)
Can self-renew
Produce one of 2 kinds of multipotential precursor cells
Cannot be identified by morphology but can be recognized by cell surface markers
Compare Myeloid and Lymphoid multipotential precursor cells that are produced by hematopoietic stem cells
Myeloid: gives rise to all blood cell lines except lymphocytes
Lymphoid: give rise to lymphocytes
List the five categories of leukocytes and indicate which are granulocytes and which are agranulocytes.
Neutrophils (granulocyte)
Basophils (granulocyte)
Eosinophils (granulocyte)
Monocytes (agranulocyte)
Lymphocytes (agranulocyte)
what is the end product of Erythroid CFU’s
produces RBC’s
what is the end product of Megakaryocyte CFU’s
produces platelet-forming cells
what is the end product of Basophil CFU’s
WBC
what is the end product of Eosinophil CFU’s
WBC
what is the end product of Granulocyte-Macrophage CFU’s
WBC
list the developmental stages
of Macrophages and indicate which cell stages can divide and which are normally found in the circulation
Monoblast *
Promonocyte
Monocyte **
Macrophage
list the developmental stages
of Neutrophils and indicate which cell stages can divide and which are normally found in the circulation
Myeloblast *
Promyelocyte *
Myelocyte *
Metamyelocyte
Band Cell **
Neutrophil **
list the developmental stages
of Eosinophils and indicate which cell stages can divide and which are normally found in the circulation
Myeloblast *
Promyelocyte *
Myelocyte *
Metamyelocyte
Band Cell **
Eosinophil **
list the developmental stages
of Basophils and indicate which cell stages can divide and which are normally found in the circulation
Myeloblast *
Promyelocyte *
Myelocyte *
Metamyelocyte
Band Cell **
Basophil **
(Same as Eosinophil)
Describe the role of ferrotransferrin in the transfer and uptake of iron
Ferrotransferin binds to a transferrin receptor dimer and is then internalized into the cell
describe the process of iron transfer and reuptake in a cell (be sure to mention ferrotransferrin and apotransferritin)
The low pH value in the endosome that endocytoses the ferrotransferrin-transferrin receptor complex, dissociates Fe3+ into the cytosol of the cell and what’s still bound to the transferrin receptor is known as apoferritin
The Apoferritin-transferrin receptor complex is then returned to the plasma membrane where the neutral pH allows apoferritin to dissociate from the transferrin receptor, into the extracellular space
List the 3 major groups of hematopoietic growth factors
Colony-stimulating factors
Erythropoietin and Thrombopoietin
Cytokines (primarily interleukins)
For each of the three groups of colony-stimulating factors, indicate source of origin and role in hematopoiesis.
Granulocyte/monocyte CSF’s: produced by endothelial cells, T cells, fibroblasts, and monocytes
Granulocyte CSF’s: produced by endothelial cells, fibroblasts and macrophages
Monocyte CSF’s: N/A
What are the sources of Erythropoietin and Thrombopoietin?
Erythropoietin: produced in the kidney in a response to a decrease in O2 saturation
Thrombopoietin: produced in the kidney, parenchymal cells, and sinusoidal endothelial cells in the liver
What is the role of erythropoietin in hematopoiesis?
once in the bone marrow, EPO induces the binding of STAT5 to JAK2, which phosphorylates STAT5 and sends it into the nucleus to turn on RBC synthesis genes
What is the role of thrombopoietin in hematopoiesis?
directs the formation of megakaryoblasts
What do cytokines do?
mediate positive and negative effects on cellular quiescence, apoptosis, proliferation, and differentiation by engaging specific receptors and activating these pathways
List examples of cytokines and differentiate the most common kind
Interleukins (most common)
Interleukin-3
GM-CSF
Fit-3 ligand
Kit ligand
