origin of blood cells Flashcards
what is Haematopoeisis?
production of RBC, white blood cells and platelets from haematopoetic stem cells
why does haematopoeisis take place (4)?
to maintain balance between self renewal, migration, cell death, terminal differentation
Where does haematopoiesis take place in the first trimester?
Yolk sac
Where does haematopoiesis take place in the second trimester?
Liver and spleen
Where does haematopoiesis take place in the third trimester?
Central, peripheral skeleton
Where does haematopoiesis take place in infancy?
Throughout bone marrow
Where does haematopoiesis take place in adulthood?
Axial skeleton
What is included in the axial skeleton (5)?
Vertebral bones, sternum, ribs, pelvis, proximal ends of humerus and femur
Structure of bone marrow?
Spongy jelly-like tissue inside bone.
Lots of blood vessels to bring nutrients and take away new blood cells
What happens in red marrow?
Active haematopoiesis
What is yellow marrow filled with?
Fat cells
Give the four stages of basic blood cell maturation
Stem cells
Progenitor cells
Precursor cells
Effector cells
What does blood cell differentiation depend on?
Growth factors
What do lymphoid stem cells mature into?
T and B lymphocytes
What can myeloid stem cells turn into (6)?
Erythrocytes Neutrophil Monocytes Eosinophil Basophil Megakaryocyte
Where do pluripotent stem cells primarily reside?
Marrow- small number in circulation
What is the surface antigen on pluripotent stem cells?
CD34+
What do pluripotent stem cells look like?
Small lymphocytes
What does disfunction in pluripotent stem cells lead to?
Aplastic anaemia or certain types of leukaemia
How much can pluripotent stem cells self renew?
Unlimited
What are multipotent stem cells derived from?
Pluripotent stem cells
Are multipotent stem cells capable of cell renewal?
Yes
What do lymphoid stem cells give rise to?
Mature lymphocytes
What do myeloid stem cells give rise to?
Red cells, granulocytes and platelets
What type of malignancies can lymphoid stem cells give rise to?
Lymphoproliferative
What do myeloid stem cells give rise to if somethings wrong?
Myeloproliferative leukaemia
What are progenitor cells derived from?
Multipotent stem cells