Haematopoiesis Flashcards
What are stem cells?
Cells that can self renew (make more stem cells) and differentiate into mature specialized cells
What are transient amplifying cells?
Cells that are immature but lost the capacity to self-renew; highly proliferative and amplify the output of stem cells
What are mature cells?
Cells that carry specialized tissue function (may or may not have lost proliferative capacity)
List the 10 cells in blood and their function
RBC: O2 transport
Platelets: clotting, inflammation
Neutrophils: non-specific immunity, bacteriocidal
Macrophages: phagocytosis, antigen presenting
Dendritic Cells: antigen presenting
Eosinophils: allergy, parasite, tissue remodeling
Basophils: allergy, parasite, angiogenesis
NK Killer cells: antitumor and viral response
T cells: specific immunity
B cells: specific secretory immunity (antibody)
Where are adult hematopoietic stem cells found? what is their function? What are they derived from?
adult HSC are derived from mesodermal precursors (act as transient amplifying cells) in early development
- found in bone marrow
- produce all the blood cells
- act as stem cells
What are the 3 overarching methods to show clonality?
Single cell assays
retroviral tagging and southern blot
chromosome tagging/translocations
Where do the first hematopoietic cells come from in embryogenesis?
Yolk sack (transient) , aorta gonad mesonephros (first source of long lived HSC), fetal liver, spleen, bone marrow
What is the difference between adult and embryogenic hematopoiesis?
Embryogenic is faster, multifocal (AGM, yolk sac, liver, bm, spleen) whereas adult is only BM
embryogenesis is also much faster and different versions of blood cells made in embryonic
How do hematopoietic cells home and traffic?
Naive homing to lymph nodes
inflammatory homing
What is the HPC trafficking process? what does it require?
- rolling adhesion
- tight binding
- diapedesis (passage of blood cell through capillary)
- migration
Requires: rolling, activation, firm adhesion, diapedesis
