Lymphoid system Flashcards
What are the three main classes of lymphocytes?
B cells
T cells
NK cells
Where do the arterial and venous vessels serving the node enter and leave lymph nodes?
Hilum
Where do lymph eventually enter the venous system?
Junction of the R or L subclavian and jugular veins
Which lymphocytes are involved in Humoral immunity?
B lymphocytes
Which lymphocytes are involved in cell mediated immunity?
T lymphocytes
How are resting B lymphocyes arranged in lymph nodes?
Primary follicles
Where in the lymph node do activated B cells go?
Germinal centres
If B cells are particularly prominant in a lymph node what kind of conditions are you thinking about?
Autoimmune
Infections (bacterial)
If T cells are particularly prominant in a lymph node what kind of conditions are you thinking about?
Viral infection
Drugs such as phenytoin
What does the red pulp of the spleen contain?
Sinusoids and cords
What does the spleen do, from an immunological perspective?
Acts as a filter for blood - detects retains and eliminates unwanted, foreign or damaged material and facilitates immune response to blood borne antigens.
What is the triad of symptoms seen in hypersplenism?
- Splenomegaly
- Fall in one or more of the cellular components of blood
- Correction of cytopenias
What three disease can cause hyposplenism?
Coeliac disease
Sarcoidosis
Sickle cell disease
What are the two main functions of the lymphatic system?
Return lymph to the circulation
Filter lymph before return to circulation
In what conditions in the lymph node response primarily due to B cells?
Autoimmune conditions
Infections
In what conditions in the lymph node response primarily due to phagocytes?
Draining of a tumour site
In what conditions in the lymph node response primarily due to T cells?
Viral infections
Drugs such as phenytoin
What artery supplies the spleen and what is this artery a branch of?
Splenic artery - branch of the coeliac trunjk
Describe the venous drainage of the spleen?
Drained by the splenic vein which joins with the superior mesenteric vein to form the portal vein.
Describe the immunological function of the spleen
Detects retains and eliminates unwanted, foreign or damaged material
Facilitates the immune response to blood borne antigens
What does the red pulp of the spleen contain?
Sinusoids which are filled with blood
Splenic cords
Marginal zone next to the white pulp
What do the splenic cords contains?
Macrophages
Fibroblasts
Cells in transit
What is the main function of the red pulp of the spleen?
Mechanical filtration of red blood cells
What is the main function of the white pulp of the spleen?
Activation of the immune response through humeral and cell mediated pathways
