PRELIM L1: WBC DEVELOPMENT, KINETICS, AND FUNCTIONS Flashcards
STATUS: UNCOMPLETED
reference interval for total wbc count
4.5 x 10^9/L-11.5 x 10^9/L
two forms of neutrophils
band and segmented
T or F:
segmented neutrophils make up the majority of circulating wbcs
T
neutrophils share a common progenitor with what wbc
monocyte
common progenitor of neutrophils and monocytes
granulocyte-monocyte progenitor (GMP)
major cytokine responsible for the stimulation of neutrophil production
granulocyte colony-stimulating factor (G-CSF)
three pools neutrophil development in the bone marrow
stem cell pool
proliferation (mitotic) pool
maturation (storage pool)
stem cell pool consists what kind of cells
HSCs
proliferation pool consists what kind of cells
dividing cells
order of maturation of cells in the proliferation pool
CMPs>GMPs>myeloblast>promyeloblasts>myelocytes
maturation pool consists what kind of cells
metamyelocytes, band neutrophils, segmented neutrophils
T or F:
HSCs, CMPs, and GMPS can be distinguished using a Romanowsky stain
F
they are indistinguishable
how can HSCs, CMPs, and GMPs be identified
surface antigen detection by flow cytometry
other term for colony-forming units (CFU)
colony-forming units-granulocyte, erythrocyte, monocyte, and megakaryocyte (CFU-GEMMs)
what do HSCs, CMPs, and GMPs resemble under Romanowsky staining
early type 1 myeloblasts or lymphoid cells
myeloblasts make up how many percent of the nucleated cells in the bone marrow
0-3%
size of myeloblasts
14-20 um in diameter
how many subdivision do myeloblasts have
3: type I, II, and III
N:C ration of type I myeloblast
8:1-4:1
characteristics of type I myeloblast
slightly basophilic cytoplasm, fine nuclear chromatin, two to four visible nucleoli, no visible granules
what type of myeloblast do azurophilic granules start to appear
type II
number of azurophilic granules in type II myeloblast
<20 per cell
characteristics of type III myeloblast
darker chromatin, purple cytoplasm, >20 granules per cell
what does the presence of type III myeloblast indicate
acute myeloid leukemia (should be rare in bm)
term proposed for combined type II and type III blasts because of them being indistinguishable
granular blasts
percent of promyelocytes in the bone marrow
1-5%
size of promyelocytes
16-25 um in diameter
characteristics of promyelocyte
round, eccentric nucleus; paranuclear halo (“hof”); basophilic cytoplasm full of azurophilic granules; 1-3 nucleoli
what are seen in normal promyelocytes but are absent in malignant promyelocytes of acute promyelocytic leukemia
paranuclear halo or “hof”
difference in nucleus of myeloblast and promyelocyte
visible chromatin clumping (heterchromatin)
percent of myelocytes that make up the nucleated cells in the bm
6-17%
final cell stage where mitosis occurs
myelocyte
stage where primary granules production starts to cease, and secondary granules are manufactured
myelocyte
what cell stage does dawn of neutrophilia occur
myelocyte
color of cytoplasm of myelocytes
lavender-pink
color of secondary neutrophilic granules
pale pink
characteristics of late myelocyte
smaller than promyelocytes (15-18 um); more intense nuclear heterochromatin, nucleoli are difficult to see
percent of metamyelocytes that make up the nucleated cells of bm
3-20%
characteristics of metamyelocytes
indented nucleus; increasingly clumped chromatin; absent nucleoli; size is slightly smaller than metamyelocyte (14-16 um); little residual of RNA (little basophilia)
percent of bands that make up the nucleated marrow cells in bm
9-32%
percent of bands that make up the nucleated peripheral blood cells
0-5%
all evidence of RNA is absent at this neutrophil stage
bands
stage where secretory granules (secretory vesicles) may begin to form
bands
size of nuclear indentation in band neutrophils
> 1/2 the diameter
requirement for a band to become a segmented neutrophil
filament between segments must be visible
