haemotopoiesis by stem cell therapy pptx.

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1. HEMATOPOIESIS

2. DEFINITION: Hematopoiesis  is the process that creates new blood cells within the body. The prefix hema refers to blood, and the suffix poiesis means to produce something, therefore hematopoiesis is the process of the body producing blood. Red blood cells are important for carrying oxygen from the lungs to other parts of the body. White blood cells help the body fight infections and support the immune system.  Platelets  assist with blood clotting. Hematopoiesis begins during development within the embryo of an unborn child and continues throughout the lifespan, as blood cells are continuously produced and replaced by the body.

3. What blood cells get made during hematopoiesis? Your blood cells are the building blocks of your blood. Hematopoiesis includes the production of all blood cell types, including Red blood cells (erythrocytes) White blood cells (leukocytes) Platelets (thrombocytes)

4. Red blood cells (erythrocytes)   Erythrocytes, carry oxygen from your  lungs  to organs throughout your body. They also carry carbon dioxide to your lungs so you can get rid of it by exhaling it. Your blood has more red blood cells than any other type of blood cell. The production of red blood cells is called  erythropoiesis .

5. White blood cells (leukocytes) leukocytes, fight infection and protect your body from harmful invaders, or germs. They also destroy abnormal cells. The production of white blood cells is called leukopoiesis. Broadly, the types of white blood cells are: Neutrophils . Basophils . Eosinophils . Monocytes . Lymphocytes  ( B-cells ,  T-cells  and  natural killer cells ). Neutrophils, basophils and eosinophils have similar functions and can be grouped together and called  granulocytes.  The other types of white blood cells are monocytes and lymphocytes.

6. Platelets (thrombocytes) thrombocytes, are sticky cell fragments that clump together to form a clot if you’re injured. They create a seal in damaged tissue that prevents you from losing too much blood. The production of platelets is called thrombopoiesis.

7. Before birth Blood cell production starts when you’re still in the  uterus . It begins in the  yolk sac , a structure that surrounds an embryo at the beginning of pregnancy. Toward the end of pregnancy, most blood cell production happens in your bone marrow. Key milestones in hematopoiesis during pregnancy are: Week 3 : A type of red blood cell slightly less developed than the red blood cells that get made during adulthood is made in the yolk sac. Months 2 & 3 : Red blood cells and platelets get made in your liver and spleen. White blood cells get made in your liver, spleen and  thymus . Month 5 : Most blood cell production happens in your bone marrow. The thymus, spleen and other lymph tissue also make some types of white blood cells.

8. What happens during red blood cell production (erythropoiesis)? Red blood cell production occurs in your bone marrow. An HSC matures into a precursor cell called an erythroblast. An erythroblast becomes an immature red blood cell called a reticulocyte. Finally, a reticulocyte develops into a mature red blood cell.

9. What happens during white blood cell production (leukopoiesis)? Granulocyte production Granulocytes (basophils, eosinophils and neutrophils) get made in your bone marrow. An HSC follows a development path called the myeloid cell line for granulocyte production. The word “myeloid” means “relating to the bone marrow” — where granulocytes get made. For granulocytes to form, an HSC becomes a precursor cell called a myeloblast. A myeloblast forms a myelocyte, which later becomes a basophil, eosinophil or neutrophil.

10. Mononuclear cell production Monocytes get made in your bone marrow, while lymphocytes (B-cells, T-cells and natural killer cells) get made in your bone marrow and other lymph tissue. For instance, very young forms of lymphocytes develop in the bone marrow and then travel to the thymus, where they will mature and develop into T-cell lymphocytes. Monocytes   develop along the myeloid cell line : Monocytes originate in your bone marrow, which means that they’re part of the myeloid cell line. They become a precursor cell called a monoblast before maturing into a fully developed monocyte. Lymphocytes develop along the lymphoid cell line : Lymphocytes originate in lymph tissue, including bone marrow and other lymph tissue, like your thymus. As a result, HSCs that eventually become lymphocytes develop along the lymphoid cell line. HSCs become precursor cells called lymphoblasts. They eventually differentiate into T-cells, B-cells or natural killer cells.

11. Platelet production (thrombopoiesis) Platelet production occurs in your bone marrow, where an HSC matures into a precursor cell called a megakaryoblast. The megakaryoblast becomes a megakaryocyte. Fragments of the megakaryocyte break off, becoming platelets.

12. How long does hematopoiesis take? Red blood cells survive for about 120 days. White blood cells survive from a few hours to a few days. Platelets survive for about five to nine days.