Hematopoietic Agents Flashcards
All hematopoietic cells develop from what type of cells?
Pluripotent hematopoietic stem cells in the bone marrow
What is the deficiency state of platelets?
Thrombocytopenia
What is the deficiency state of red blood cells (erythrocytes)?
Anemia
What are the two groups of growth factors?
Multilineage and lineage-specific
Difference between multilineage and lineage-specific growth factors
Multilineage- stimulate multiple lineages
Lineage-specific- stimulate differentiation of a single lineage
What is the role of erythrocytes?
Transporting oxygen from the lungs to the tissues of the body
True or false: Each hemoglobin molecule consists of two similar polypeptide chains, and each chain contains a binding site for molecular oxygen
False. Four similar polypeptide chains
What is the major form of adult hemoglobin?
Hemoglobin A (2 alpha and 2 beta chains)
True or false: Fetal hemoglobin (HbF) contains 2 alpha chains and 2 beta chains
False. 2 alpha chains and 2 gamma chains
Which is more potent, HbA or HbF?
HbF has a higher affinity for oxygen to facilitate oxygen transfer from mother to fetus
How is HbF converted to HbA?
After birth, DNA methylation inactivates the γ globin gene, and expression of the β globin gene rises
How is HbS formed and what disorder is it responsible for?
Point mutation in the beta globin gene results in HbS, which is responsible for sickle cell anemia
True or false: In β thalassemia, the β chain is structurally and functionally normal but under expressed
True
Why does CKD inhibit erythropoiesis?
The kidney is the site of production of EPO, which stimulates the bone marrow to produce erythrocytes
TPO is the precursor for what type of cells?
Platelets (thrombocytes)
Where is TPO produced?
Mainly in the liver, but also in the proximal convoluted tubule of the kidney
What are the 3 erythropoiesis stimulating agents used clinically in the U.S.?
.Recombinant human erythropoietin (rhEPO, aka epoetin alfa)
.Methoxy polyethylene glycol (PEG) (epoetin beta)
.Darbepoetin alfa
MOA of Erythropoiesis Stimulating Agents
Stimulate erythropoietin receptor and induce erythropoiesis
Agents that induce HbF
5-azacytidine and hydroxyurea
MOA of hydroxyurea
Blocks cell division by inhibiting ribonucleotide reductase
MOA of 5-azacytidine
Reverses methylation of the beta globin gene
Agents that stimulate leukocyte production are used in the treatment of what?
Cancer and chemotherapy induced neutropenia
Agents that stimulate leukocyte production
.Recombinant human G-CSF (filgrastim)
.Pegylated, long-acting form, PEG-G-CSF (PEG-filgrastim)
.Recombinant human GM-CSF (sargramostim).
What is the main adverse effect of recombinant human G-CSF?
Bone pain, which resolves upon discontinuation of the drug