Hemopoiesis Flashcards
(26 cards)
In the adult RBM where does hemopoiesis occur
Skull Sternum Vertebrae Ribs Pelvis and Proximal epiphyses of: Femur Humerus
Where are lymphocytes formed
the red marrow and in the lymphatic tissue
What are the 3 phases hemo occurs in the embryo n fetus
- yolk sac
- hepatic
- bone marrow
The yolk sac phase begins at what what and by the formation of what
Begins in the 3rd week of gestation
Begins by the formation of blood islands in the wall of the yolk sac of the embryo (Yolk Sac Phase)
What trimester does the hepatic phase begin
In the 2nd trimester, with the development of the liver, hemopoiesis shifts to the liver (Hepatic Phase)
During the 2nd trimester liver is the major blood forming organ
When is the bone marrow phase
Hemopoiesis shifts to:
Bone marrow
This process begins during the 2nd trimester and by the 3rd trimester its fully bone marrow
Before birth bone marrow is the major blood forming organ (Bone Marrow Phase)
What is the monophyletic theory of hem
All blood cells are derived from a common hemopoietic stem cell (HSC)
What kind of stem cell is a hemo stem cell and what is it capable of
Is a pluripotential stem cell
i.e. capable of differentiating into all the blood cell lineages
Also divides to maintain its own population
Cannot be identified in routine preparation
Special immunocytochemical methods must be used
Hemo stem cell gives rise to which two major colonies of multipotential progenitor cells:
Common myeloid progenitor cells (CMP cells):
Colony-forming-units-granulocyte, erythrocyte, monocyte, megakaryocyte (CFU-GEMM)
Differentiate into specific lineage-restricted progenitors
Common lymphoid progenitor cells (CLP cells)
Two main lineage-restricted progenitors. These include:
• Megakaryocyte/
Erythrocyte
Progenitor Cells
(MEP Cells)
• Granulocyte/ Monocyte Progenitor Cells (GMP or CFU-GM Cells)
Megakaryocyte/erythrocyte progenitor cells (MEP Cells):
Bipotential
Give rise to:
Megakaryocyte-committed progenitor cells (MKP or CFU-Meg) and
Erythrocyte-committed progenitor cells (ErP or CFU-E)
MKP and ErP are Monopotential
Granulocyte/Monocyte Progenitor Cells (GMP or CFU-GM Cells):
Multipotential
Give rise to:
Neutrophil progenitors
Eosinophil progenitors
Basophil/Mast cell progenitors:
–>Basophil progenitors (in bone marrow)
–>Mast cell progenitors (in the gastrointestinal mucosa)
Monocyte progenitors
Dendritic cells (antigen presenting cells)
Common Lymphoid Progenitor Cells (CLP cells) AKA ?
colony-forming-units-lymphoid (CFU-L)
Colony-forming-units-lymphoid (CFU-L)
Multipotential
Differentiate into:
T lymphocytes
B lymphocytes
Natural killer (NK) cells
Dendritic cells
Hemopoietic Stem Cells (HSC) Pluripotent Cells to Myeloid Lineage of Cells or Common Myeloid Progenitor Cells Multipotenet cells
Is dependent on what
Dependant on surface receptors, cytokines and growth factors
(Surface receptors interact with Colony Stimulating Factors - CSF)
Myeloid Lineage of Cells
or
Common Myeloid Progenitor Cells
Multipotenet cells
To
Megakaryocyte/
Erythrocyte Progenitor Cells
or
Bipotent Cells
Is triggered by what
Triggered by Erythropoietin and
Cytokines, interleukin 1 (IL-1)
and interleukin-3 (IL-3)
Myeloid Lineage of Cells
or
Common Myeloid Progenitor Cells
Multipotenet cells
to
Granulocyte/Monocyte Progenitor Cells
or
Granulocyte/Monocyte Colony Forming Units (CFU-GM)
Multipotent Cells
is triggered by?
Cytokins
Granulocyte/Monocyte Progenitor Cells or Granulocyte/Monocyte Colony Forming Units (CFU-GM) Multipotent Cells differentiation is triggered by what
Triggered by interleukins,
transcription factors and CSF
Megakaryocyte/
Erythrocyte Progenitor Cells
or
Bipotent Cells
to
Erythropoietin-Sensitive Erythrocyte-Committed Colony Forming Unit (CFU-E)
or
Erythrocyte Committed Progenitor Cells (ERP)
is triggered by?
Triggered by
Transcription Factor GATA-1
Hemopoietic Stem Cells (HSC)
Pluripotent Cells
to
Lymphoid Colony Forming Units (CFU-L)
is triggered by?
Transcription factors
What are the 9 development stages of erythropoiesis
- Myeloid Lineage of Cells (Common Myeloid Progenitor Cells), triggered by erythropoietin
- Megakaryocyte/Erythrocyte Progenitor Cells, triggered by GATA-1
- Erythrocyte Committed Progenitor Cells
- Proerythroblasts
- Basophilic Erythroblasts
- Polychromatophilic Erythroblast
- Orthochromatophilic Erythroblast or Normoblast
- Reticulocyte
- Erythrocyte
What is a proerythrocyte
First microscopically recognizable cell
Large cell (12- 20 µm)
Large, spherical nucleus
1 or 2 nucleoli
Lightly basophilic cytoplasm
Free ribosomes
Not easily identified in bone marrow smears
Describe a basophilic ery
From mitoses of Proerythroblast
Smaller nucleus and more heterochromatin
No visible nucleolus
Cytoplasm is strongly basophilic
Due to large numbers of free ribosomes (polyribosomes)
Ribosomes synthesize hemoglobin
Describe Polychromatophilic Erythroblast
Cytoplasm displays both acidophilia (because of the staining of hemoglobin) and basophilia (because of the staining of polyribosomes)
Overall gray or lilac color to cytoplasm or distinct pink and purple regions
Nucleus smaller than in basophilic erythroblast
Nucleus shows prominent heterochromatin forming a checkerboard pattern (characteristic identifying feature)
