Myelopoiesis is the process of origin, development, and maturation of granulocytes.
Site: It occurs in the bone marrow.
Stages of Myelopoiesis
Pluripotent Haematopoietic Stem Cells
↓
Colony Forming Unit - Spleen
↓
Colony Forming Unit - Granulocytes, Monocytes
↓
Myeloblast
↓
Promyelocyte
↙ ↓ ↘
Neutrophil myelocyte Basophil myelocyte Eosinophil myelocyte
↓ ↓ ↓
Neutrophil metamyelocyte Basophil metamyelocyte Eosinophil metamyelocyte
↓ ↓ ↓
Polymorphonuclear Neutrophil Polymorphonuclear Basophil Polymorphonuclear Eosinophil Changes During Myelopoiesis
- Golgi apparatus and Endoplasmic Reticulum starts appearing
- Condensation of nucleus
- Synthesis of protein for the specific granules and lysozymes
Regulators of Myelopoiesis
- Colony Stimulating Factors (CSF)
- Granulocyte Colony Stimulating Factor (G-CSF)
- Granulocyte – Monocyte Colony Stimulating Factor (GM-CSF)
- Haemopoietic Growth Factors
- Interleukin-3
- Interleukin-5
Clinical Correlates
- Granulocytosis: Abnormal increase in the number of granulocytes
- Neutrophilia
- Basophilia
- Eosinophilia
- Granulocytopaenia: Abnormal reduction in the number of granulocytes
- Neutropaenia
- Basopaenia
- Eosinopaenia
