Haematopoiesis, blood-forming tissues and haematopoietic growth factors
Where blood is made across life, the stem cell hierarchy and marrow niche, the growth factors that drive each lineage and how their receptors signal through JAK2, the cell kinetics behind the chemotherapy nadir, and clonal haematopoiesis.
Tier 2Medical sciences concept
Written with AI assistance and fact-checked against the sources below. For exam study, not clinical decisions. How notes are made
At a glance
- An adult makes about 2 x 10^11 red cells, 1 x 10^11 platelets and up to 1 x 10^11 neutrophils every day from a small pool of haematopoietic stem cells.
- Sites move from yolk sac to liver and spleen to bone marrow. In adults, active marrow shrinks to the axial skeleton and proximal long bones.
- Each lineage is driven by its own growth factor: EPO for red cells, TPO for platelets, G-CSF for neutrophils. Several of their receptors signal through JAK2.
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Sources
- Hoffbrand's Essential Haematology (8th ed.)Wiley-Blackwell (Hoffbrand and Steensma, 2019), 2019
- Postgraduate Haematology (7th ed.)Wiley-Blackwell (Hoffbrand, Higgs, Keeling and Mehta, 2016), 2016
- Hematopoiesis: an evolving paradigm for stem cell biologyCell (Orkin and Zon, 2008;132:631-644), 2008
- Age-related clonal hematopoiesis associated with adverse outcomesNew England Journal of Medicine (Jaiswal et al., 2014;371:2488-2498), 2014
- Clonal hematopoiesis and risk of atherosclerotic cardiovascular diseaseNew England Journal of Medicine (Jaiswal et al., 2017;377:111-121), 2017
- Last updated
- 14 November 2026
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