Production of WBC Flashcards
what is the primary site of Haematopoesis
Bone marrow
where are the primary sites in adults located?
- Vertebrae
- Mostly flat bones
3.Iliac bones - Ribs
- End of long limb bones
Primary site for foetus
- all bones
- Liver and spleen
The bone marrow is very cellular
What are repertoires?
range of genetically distinct BCRs and TCRs in a given host
The larger the repertoire the more threats can be recognised
where does b cell maturation take place
B cell maturation occurs in the peripheral tissues
Where does B cell repertoire occur?
B cell repertoire occurs in the bone marrow
Stages of haematopoesis of B cells:
Hematopoietic stem cells renew themselves (self-renewal) and produce lymphoid progenitors in the bone marrow
The lymphoid progenitor produces B cell progenitor in the bone marrow
B cell progenitor produces B cells in the peripheral tissues
When does white blood cell production increase?
- infection
- inflammatory event
- some other conditions
Types of T cells
T helper cells
T cytotoxic cells
what are immature B cells called?
Thymocytes as they migrate from bone marrow to thymus
Stages of T cell selection
- Immature T cells migrate from the Bone marrow to the thymus
- Positive selection- that T cells are functional ie they have TCR that can be activated
- Negative selection- removes TCR that recognise self-antigens (presentation of self-antigens to T cells in the thymus and if they receive a strong signal, they undergo apoptosis)
- Final selection and exit
What does self mean in immunology?
anything recognized by the immune system as part of your normal molecular make-up
what is foreign in immunonology
anything recognised by the immune system as foreign
What is thymic involution?
shrinking of the thymus with age
- this is associated with reduced mass and change in structure
- results in lower thymic output
- no more t cell repertoire
Q. How does a small population of cells (e.g. 1) find a foreign protein (antigen) in a human body?
Secondary lymphoid tissue
