01 Hematopoiesis Flashcards
CD 45 + positive cells
Granulocyte precursors
Monocyte precursors
Endothelial precursors
Multipotent master stem cells
1:10^6
Progenitors of mesynchymal stem cells, endothelial progenitors, and hematopoietic SCs
CD 45- negative cells
Erythroid precursors
Megakaryocytes
Myeloid
Granulocytes, Monocytes
Erythroids
Megakaryocytes
(All but Lymphocytes)
EPO
Stimulates Erythroids (CFU-E) >85% produced in kidney as hypoxic response downstream of HIF1alpha (Hypoxia inducible factor)
SE(HTN, HA, venous thrombosis, MI, Stroke, RBC aplasia)
Thrombopoeitn (TPO)
Stimulates megakaryocyte differentiation
(CFU-meg)
MPL receptor binding
Eltrombopag/romiplostim- TPO analogues for thrombocytopenia (SE HA venous thrombosis, myelofibrosis)
G-CSF
Granulocyte colony stimulating factor
Stimulates CFU-G
Used with low neutrophil counts for fevers infection treatment
SE(fever, bone pain, fluid retention/pulmonary edema)
M-CST
Macrophage colony stimulating factor
Hallmarks of differentiation
1) Decreasing size
2) Cytoplasm becomes more eosinophilic as protein outnumbers RNA
3) Decreasing nuclear size (erythroids)
4) Increasing nuclear segmentation in granulocytic cells
5) Specific granules (generally more eosinophilic)
6) Closing of chromatin and loss of nucleoli
Erythrocyte size
Generally 7.5u
Erythroid integral proteins
Ankyrin, Actin, Spectrin, and Band 3 - (HCO3- X Cl-) exchanger
Neutrophil life span and percentage, granules
34-71% WBCs 12u in diameter Few day lifespan Lysozyme, hydrolases, and ROS Alk Phos, Aminopeptidase, Collagenase
Eosinophil life span and percentage, granules
0-7%
12u
2 week life span
Major basic protein, leukotrienes
Basophils percentage, size, life span, granule content
0-1% of WBCs
12u
Heparin, histamines in granules (cause Mast degranulation)
Few year Lifespan
Monocyte size, granules, percentage, lifespan
5-12% life span of several months
15u diameter
agranular- phag and APC
Lymphocyte characteristics
<10u
B and T cells
Perforin and granzyme or no granules
Megakaryocyte and platelettes
Plateletts <2u
PDGF and clotting factors in granules
HSC markers
C-Kit = CD117 +
CD34+
(CD 45 -)
Erythroid stages
1) Proerrythroblast (nucleoli and basophilic cytoplasm)
2) Basophilic erythroblast (closing nuclei “crayon” basophilic cytoplasm)
3) polychromatic erythroblast (chunky nuclei with multicolored Agranular cytoplasm
4) orthochromatic erythroblast- gray and pinking cytoplasm with chunky nuclei
5) Reticulocyte (blue cytoplasmic inclusions) and extruded nuclei
6) erythrocyte
Myeloid stages
1) Myeloblast- open chromatin many nucleoli agranular
2) Progranulocyte -primary granules obscure nucleus
3) myelocyte- Closed chomatin with no nucleoli more eosinophlic granules
4) Metamyelocyte- smal nuc. No nucleoli, eosinophilic granules only
5) Band- Eosinophilc 2ndary granules only, no nucleoli- partially lobulated
Proerythroblast
Agranular basophilic cytoplasm with open chromatin and many nucleoli
Basophilic normoblast
Closing chromatin- few nucleoli- “crayon like” basophilic cytoplasm
Polychromatophilic normoblast
Gray/blue cytoplasm with small chunky nucleus
Orthochromatophilic normoblast
Grray-pink cytoplasm with small chunky nucleus
Reticulocyte
Gray/eosinophilic cytoplasm with blue staining inclusions (can be found in the peripheral blood)
Lymphocyte histology
small
high N/C ratio
Hematogone
B cell precursor
high N/C ratio
Nucleoli and open chromatin
Monocyte hystology
Large
Horseshoe nuclei with delicate granules
