Haemopoiesis Flashcards
Define haemopoiesis
Formation of blood cells
What is the role of erythrocytes?
O2/Co2 transport
What is the role of platelets?
Primary haemostasis
What cells are granulocytes?
Neutrophils, eosinophils, basophils
What is the role of neutrophils?
Phagocytosis and acute inflammation
What is the role of eosinophils?
Destroy parasites
Modulate hypersensitivity reactions
What is the role of basophils?
Modulate hypersensitivity reactions
What is the role of monocytes/macrophages?
Chronic inflammation
Modulate immune reactions
Phagocytic clearance
Regulatory functions
What is the role of B lymphocytes?
Humoral immunity (antibodies)
What is the role of T lymphocytes?
Cell mediated immunity
Regulatory functions
What is the role of natural killer cells
Anti-viral/tumour
Which cells in the blood have the longest life span, which have the shortest
RBCs ~120 days (longest)
Platelets ~7-10 days
Neutrophils ~7-8hrs
Where are all haemopoeitic cells derived from?
Haemopoietic stem cells
Where does haemopoiesis occur weeks 5-10
Yolk Sac
When does haemopoiesis in the liver start?
Week 6
When does haemopoiesis in the spleen start?
Week 12
When does haemopoiesis in the bone marrow start?
Week 16
Which bones does haemopoiesis in the adult occur in?
Axial skeleton (vertebrae, sternum, ribs, skill, pelvis, shoulder girdle)
What is bone marrow surrounded by?
Vascularised and innervated bone
What is the interface between bone and bone marrow called?
Endosteum
What is the endosteum covered in?
Osteoblasts and osteoclasts
Where do the arteries in the bone marrow feed into?
Sinusoids
How do mature cells pass into the blood from the marrow?
Through fenestrations in endothelial cells
What is the difference between red and yellow marrow?
Red marrow is haemopoietically active
Yellow marrow is not (fatty)
How is haemopoiesis assessed?
Examination of blood (count, cell indices, morphology)
Examination of bone marrow
