hematopoisis Flashcards
When is red blood cells formed in the yolk sac?
3-8 weeks
When is red blood cells formed in the liver?
fetus: 6-30 weeks
When is red blood cells formed in the spleen?
fetus: 28 weeks
When is red blood cells formed in the bone marrow?
28 weeks onward
Where does hematopoiesis occur in the adult
skull, clavicle, verebrae, ribs, pelvis, sternum, ends of long bones
What does the hematopoietic compartment consist of?
highly vascular, hematopoietic stem cells including committed precursor cells and maturing cells
What does the marrow stromal compartment consist of?
production of growth factors, barrier (endothelial cells), adipose cells, macrophages
what is BFU-E
colony forming unit for RBC
what is CFU-mega
megakaryocyte precursor
what is CFU-GM
monocyte and neutrophil
what is prothymocyte?
T lymphocyte precursor
Characteristics of Stem cell factor
SCF-produced by fetal tissue and bone marrow;
weak stimulator of pluripotent cell;
makes stem cells responsive to other cytokines
Flt3
related to SCF; acts like SCF
What does IL-3 do?
myloid cell line differentiation
What does IL 1 do?
Develop lymphoid cells (B,T)
What does IL-4 do?
Develop lymphoid cells (B,T)
What does IL-2 do?
In absence of other IL then it develops T cells from lymphocytes;
if IL-6 is present then it makes B cells
What does IL-6 do?
It makes B cells from lymphocytes
What does GM-SF do?
forms leukocytes and reticulocytes
what does G-CSF do?
increase neutrophils
M-CSF
stimulates monocytes and macrophages
keynote characteristics of erythropoiesis
large central nucleus in pro stage;
enters blood as reticulocyte (nucleus gone, but residual polyribosomes on stain)
Keynote characteristics of thrombocyte development
kidney shape nucleus in megakaryoblast;
huge megakaryocyte;
spits out platelets (very small)
identify cells under a scope
ok
What do neutrophils do?
phagocytize bacteria;
release antimicrobial chemicals
What do eosinophils do?
phagocytize antigen-antibody complexes, allergens, inflammatory chemicals;
antiparasitic and antibacterial
what do basophils do?
secrete histamine and heparin;
inflammatory rxns during immune responses and allergies
keynote features of granulocyte synthesis
just before released into blood it has an indented nucleus;
horseshoe shaped nucleus in blood;
quartinary nucleus structure when mature
what do monocytes do?
phagocytize pathogens and debri;
“present” antigens to other immune cells;
differentiate into macrophages
