11 - Haemopoiesis Flashcards
Outline the process of haemopoeisis with growth factors used.
Stem Cells –> Myeloid or Lymphoblasts
Where does haematopoiesis take place?
What are monocytes and granulocytes?
Monocytes - Precursor of macrophages
Granulocytes - White blood cells containing granules
What is the structure and function of erythrocytes?
- Biconcave carry oxygen
- Live 120 days and then removed by liver or spleen. Iron recycled, protoporphyrin broken down to bilirubin and excreted in faeces
- Peritublar endothelial cells detect hypoxia and release erythropoeitin
Where are the following released from:
- Erythropoietin?
- Thromobpoietin?
- G-CSF?
- Interleukins?
- Kidney
- Liver, Kidney, Skeletal muscle cells, stromal cells of bone marrow
- Macrophages and immune cells and endothelium
- Activated T-cells and mast cells
What are leucocytes?
Nucleated white blood cells
What is the structure and function of a neutrophil?
What is the structure and function of eosinophils?
What is the structure and function of Basophils?
What is the structure and function of monocytes?
Distinguish what white blood cells look like under the microscope
What are the different types of T-lymphocyes?
Helper:
- CD4 on surface
- Recognise other immune cells by HLA Class II
- Stimulate cytotoxic t-cells
- Aid humoral immunity (convert b cells to plasma cells)
Cytotoxic:
- Recognise and kill virally infected cells by stimulating apoptosis
NK Cells:
- Stimulate virally infected cells or cancer cells to undergo apoptosis by releasing granozymes and perforin
What is the structure and function of B-cells?
Antibodies on surface, convert to plasma cells and secret immunoglobulins
What is the structure of platelets?
Originate from megakaryocytes
Contain granules:
- Alpha-Granules - Fibrinogen, Factors and other large molecules
- Dense Granules - ADP and Calcium
Briefly outline how platelets form clots.
- Injury
- Vessel contracts due to serotonin release
- Platelet adhesion to endothelial wall
- Platelet aggregation with other platelets
- Platelets provide phospholipid surface for binding of clotting factors
What is a cytokine?
Growth factor, e.g IL6 or G-CSF that stimulates chemotaxis and phagocytosis
How could you overcome an issue with a low RBC count?
Inject EPO
What order do white blood cells arrive at the scene of infection?
Never Let Monkeys Eat Bananas
What is thalassaemia?
Any hereditary haemolytic disorder caused by faulty haemoglobin synthesis
What is:
- Haemolytic Anaemia
- Aplastic Anaemia
- Haemophillia
- Removal of RBC before 120 day. High reticulocyte count. Treat with blood transfusion or splenectomy
- Haemopoietic stem cells damaged. Bone marrow transplant. Low reticulocyte count
- Lack of clotting factors so blood cannot clot
What is chronic myeloid leukemia?
Myeloid precursor mutated so cells cannot mature into mature WBC’s. Too many immature WBC’s released and don’t work properly, accumulate in organs and stop them working properly
What are the words associated with high and low blood cell counts?
High:
- Thrombocythemia
- Leukemia
- Polycythemia (RBC)
Low:
- Anaemia
- Leucopenia
- Thrombocytopenia
PANCYTOPENIA = LOW EVERYTHING
If a primary haemotological disorder is suspected what do you do?
- Take bone marrow transplant using trephine
- Superior posterior iliac crest
- Can then stimulate bone marrow to release stem cells and use stem cells for bone marrow transplant
What does a reiticulocyte look like?
