Hematopoiesis Flashcards
What are the two compartments within the bone marrow
Vascular & hematopoietic
What do adventitial cells (reticular cells) secrete?
Hematopoietic growth factors, produce reticular fibers
Which cells does the common lymphoid progenitor give rise to?
T, NK, and B cells
Which cells does the common myeloid progenitor give rise to?
Platelets, RBCs, Neutrophiles, Eos, Bas
Which phase of hematopoiesis occurs during 2 to 8 weeks gestation
Mesoblastic or yolk sac
What kind of erythrocytes are formed during the yolk sac phase?
Nucleated
When does the hepatic phase occur?
2 to 7 months intrauterine
What erythrocytes are produced during the hepatic phase?
Anucleate erythrocytes followed by megakaryocytes and granulocytes
When does the splenic phase occur?
10th week to 6-7 months intrauterine
When does the bone marrow phase occure?
6 months intrauterine until death
Site of active hematopoiesis
red marrow
When does yellow marrow begin to replace red marrow?
after 4-5 years of age
Site of less active hematopoiesis
Yellow marrow
The way in which adventitial cells regulate their size
Regulating lipolysis
After age 20 where are sites of active hematopoiesis?
Sternum, ilia, vertebral bodies, ribs, clavicles, cranial bones, and proximal ends of the femur and humerus
What is the purpose of reticular fibers in the hematopoietic compartment?
Form a mesh around the areas of blood cell formation, (mechanical support)
What is the monophyletic theory?
There is a pluripotential hematopoietic stem cell that can give rise to all the formed elements of blood
The stroma of the hematopoietic compartment consists of:
Adventitial cells, Reticular fibers, and macrophages
Where does erythropoiesis occur?
Erythroblastic islets
During erythropoiesis what is responsible for: supplying iron for heme synthesis, produce growth factors, phagocytize extruded nuclei
Macrophages
What is the order of Erythropoiesis?
Proerythroblasts, Basophilic erythroblasts, polychromatophilic erythroblasts, orthochromatic erythroblasts, reticulocytes, mature erythrocytes
Which common myeloid progenitor gives rise to the 3 types of granulocytes, monocytes, platelets, and erythrocytes?
CFU-GEMM
What is the first morhologically recognizable precursor cells in the granulocyte pathway?
Myeloblasts
What is the first morphologically recognizable precursors to erythrocytes?
Proerythroblasts
Why do orthochromatic erythroblasts have a salmon pink cytoplasm?
Loss of polyribosomes
What accompanies the transformation to mature erythrocytes?
Loss of transferrin receptors and remaining cytoplasmic organelles
Which precursor cell is committed to becoming neutrophils, eosinophils, or basophils?
Myeloblasts
Which precursor cell are formed when it begins to produce azurophilic granules
Promyelocytes
What is the order of developing cells in granulopoiesis?
Common myeloid progenitor cell, Myeloblast, promyelocyte, myelocyte, metamyelocyte, band/stab cells, mature granulocyte
Which cell type has a common precursor with granulocytes?
CFU-M, Common myeloid progenitor cell
What is the first cell stage of monopoiesis?
Promonocytes
What is the mature cell of monopoiesis?
Macrophages
What two components are included in thrombopoiesis?
Development of megakaryocytes, formation of platelets
Which cells are derived during lymphopoiesis?
B cells, T cells, NK cells, and some dendritic cells
How is hematopoiesis controlled?
Hematopoietic growth factors, which are a type of cytokine
Early HGFs
Stem Cell Factor (SCF), IL-3
Intermediate HGFs
IL-7, GM-CSF
Late HGFs
IL-4, IL-5, G-CSF, M-CSF, Erythropoietin (EPO)
What happens to cells that are not induced to continue division or differentiation by HGFs?
Apoptosis
What are the 4 commercial preparations of HGFs that are currently approved by the FDA for use in the U.S.
G-CSF (Neupogen)
GM-CSF (Leukine)
Erythropoietin (Epogen, Procrit)
Interleukin-11 (Neumega)
