What is hematopoiesis
Hematopoiesis is the formation and development of blood cellular elements. They all come from hematopoietic stem cells. New blood cells are produced all the time (100,000,000,000+ cells daily).
Hematopoietic stem cells are located in bone marrow and they are the starting point for blood cells’ production.
Blood cells are separated into 3 lineages: eryhtroid cells (red blood cells who carry the oxygen), lymphoid cells (base of the immune system) and myeloid cells (granulocytes, macrophages and megakaryocytes).
Granulocytes go through the process of hematopoiesis and that is called granulopoiesis. It takes place in bone marrow and is divided in several levels: hematopoietic stem cell – myeloblast – promyelocyte – myelocyte – metamyelocyte – band cell – granulocytes.
Blood is produced mainly in some organs like the spleen and liver (in early life). Later, the bone marrow takes over and takes care of blood cells production for the whole organism. Sometimes, if the body needs that, spleen, liver and other organs continue to produce blood cells. That process is called extramedullary hematopoiesis.
Blood cells production is greatly influenced by growth factors (SCF, Tpo, IL, GM-CSF, Epo, M-CSF and more).
Subscribe to the comments for this post