2. Contents
1. Introduction and development
2. Hematopoiesis
3. Cytokines and the Control of Hematopoiesis
4. Cytokine Receptors, Signaling Pathways, and Transcription Factors
5. Hematopoietic Microenvironment
6. References
3. โข The pioneering work of Till and McCulloch began to
define the hierarchy of hematopoietic precursor cells
using in vivo clonal assays.
โข Hematopoietic stem cells (HSCs) develop in discrete
anatomical niches, migrating during embryogenesis from
the aorta-gonadmesonephros (AGM) region to the fetal
liver, and finally to the bone marrow, where most HSCs
reside throughout adult life.
1. Introduction and development
4.
5. 2. Hematopoiesis
โขDefination :โThe processes involved in the production of all of
the various cells of the blood from the HSCs are collectively
called hematopoiesisโ
โขHighly regulated process to maintain circulating cell numbers
within relatively constant levels and to respond rapidly to
conditions requiring extra cells .
โขMaintains balance between self renewal, terminal differentiation,
migration, and cell death.
12. Progenitor Cells
โขPopulations of differentiating cells that have an increasingly limited capacity
to self-renew and are gradually more restricted in differentiation options.
โขLineage-specific transcription factors are thought to play essential roles in this
process
13.
14.
15. 3. Cytokines and the Control of Hematopoiesis
Growth factors / Cytokines
21. Transcription Factors
โขTFs associated with the activation of a particular lineage-specific
differentiation program often simultaneously inhibit alternate lineage-specific
transcription factors.
โขInterestingly, more than half of the hematopoietic transcription factors
identified have been shown to be dysregulated in hematologic malignancies
(translocations, point mutations of TF genes)
โขThus, the impaired differentiation seen in leukemia is likely due to
abnormalities of critical, discrete pathways of transcriptional control.
27. โข McKenzie SB, Williams JL. Hematopoiesis.In: Clinical labouratory
hematology, 3rd ed.Pearson;2016 p71-91.
โขSingh T. Normal hematopoiesis and evaluation of bone marrow and
peripheral blood film. In: Atlas and Text of Haematology,3rd ed.Delhi:2014.P.1-
4
โขDiseases of white blood cells, lymph nodes,spleen and thymus. In Kumar V,
Abbas A K, Aster J C, Robbins and cotran patholology basis of disease. 9th ed.
Elsevier Inc: 2016. P.579-82.
References
28. โข Gao X, Xu C, Asada N, Frenette PS. The hematopoietic stem cell niche: from
embryo to adult. Development 2018;145:1-12
โข Laffan M A, Manning R , Investigation of hemostasis, Bain B.J, Bates I, Laffan
M.A, Lewis S.M, Dacie and Lewis Practical Haematology. 11th ed. London:
2012. P.424-39
โข Mathur SC,Hutchison RE,Mahi G. Hematopoiesis .In Bain B.J, Bates I, Laffan
M.A, Lewis S.M, Dacie and Lewis Practical Haematology. 11th ed. London:
2012. P.540-58
References
