4.3 Haematopoiesis Flashcards
What is a multipotential haematopoietic stem cell? What is its alternate name?
Multipotent cells that can develop into other blood cells.
1) Common Myeloid Progenitor (erythrocytes, mast cells, granulocytes ==> macrophage)
2) Common Lymphoid Progenitor (lymphocytes==>plasma cells)
Describe the structure of an erythrocyte.
Biconcave shape, flexible, lipid bilayer, no nucleus and organelles
Describe haemopoiesis of an erythrocyte
Starts of with a nucleus and quite large then progressively loses nucleus and becomes smaller
What is the function of platelets?
Primary plug in blood vessel break
Cell fragments circulate alone but clump at site of injury
Surface for clotting factors
Name the granulocytes
Neutrophil, basophils, eosinophil,
Name APCs
Dendritic cells, macrophages, B cells
What is a natural killer cell?
Part of innate response
Stimulate sick cells to perform apoptosis
Do not need to be stimulated by APCs
Role of a B cell
Make and secrete antibodies
APC
Role of a T cell
Stimulate inflammatory cells
Stimulate B cells
Activate T killer cells
What does a mast cell do?
Releases histamine in response to injury/allergy
Vasodilation and permeability of blood vessels increases
This is so WBCs and proteins can access site easily to repair and kill of any foreign material
Describe CML
Chronic Myeloid Leukaemia - philadelphia chromosome - bone marrow makes too many WBCs
Leukaemia ?
Abnormal blood count shows increased numbers of WBC
Thrombocythemia?
Abnormal blood count shows increased numbers of platelets
Polycythemia
Abnormal blood count shows increased heamatocrit (above 55%)
What is Haematocrit?
Ratio of the volume of RBC to the total volume of blood (between 40-45%)
