Megakaryopoiesis (P) Flashcards
What are the 2 phases (or stages) of megakaryopoiesis?
1) Proliferative Phase
2) Terminal Differentiation
What are the type of megakaryocytes under proliferative phase?
Megakaryocyte progenitors
How are megakaryocyte progenitors described under proliferative phase?
Described based on their characteristics in vitro
What type of cell does all cells under proliferative phase resemble?
Lymphocytes
What are the type of megakaryocytes under terminal differentiation?
Megakaryocyte precursors
How are megakaryocyte precursors described under terminal differentiation?
Described based on their morphology in Wright-stained aspirate and H&E-stained biopsies
What does the first cell stage under terminal differentiation resemble?
Myeloblasts or pronormoblasts
Where does Megakaryocyte-Erythrocyte Progenitor arise from?
Arise from common myeloid progenitor
What are the 2 (chemical components) of Megakaryocyte-Erythrocyte Progenitor?
1) GATA-1
2) MYB
What is the meaning of BFU-Meg?
Burst-Forming Unit Meg
What are the characteristics of BFU-Meg?
1) Least mature
2) Diploid
3) Normal mitosis
4) 100 cells in vitro
What is the meaning of CFU-Meg?
Colony-Forming Unit Meg
What are the characteristics of CFU-Meg?
1) Intermediate
2) Diploid
3) Normal mitosis
4) 12 cells in vitro
What is the meaning of LD-CFU-Meg?
Light-Density Colony-Forming Unit Meg
What are the characteristics of LD-CFU-Meg?
1) More mature
2) Polyploid
3) Endomitosis
What is the (chemical component) present on LD-CFU-Meg?
RUNX1
What is the meaning of MK-I?
Megakaryoblast
What are the characteristics of MK-I?
1) Least differentiated
2) Plasma membrane blebs
3) Cytoplasmic structure starts to develop
What is the meaning of MK-II?
Promegakaryocyte
What are the characteristics of MK-II?
1) Starts with indentation of nucleus
2) Ends if full ploidy is reached
What is the meaning of MK-III?
Megakaryocyte
What are the characteristics of MK-III?
1) Easily recognized
2) Ploidy levels can be measured
What is used to measure ploidy levels of MK-III?
Propidium iodide
What is the other term for thrombocytes?
Platelets
How are platelets formed?
Result from shredding of megakaryocytes
What are the purposes of thrombopoietin?
1) Induces stem cell-megakaryocyte
2) Induces megakaryocyte progenitor-precursor
3) Induces megakaryocyte proliferation and maturation
4) Induces thrombocytopoeisis
What is the meaning of TPO?
Thrombopoietin
What are the therapeutic agents available for TPO and IL-11 (to act as an alternative for these 2 components)?
1) For TPO: romiplostim and eltrombopag
2) For IL-11: oprelvekin
What is the main function (or principle) of GATA-1?
To increase
What is the main function (or principle) of MYB?
To decrease
