Chapter 10: The Spleen Flashcards
What arteries does the splenic artery divide into?
trabecular arteries
What vessels do the trabecular arteries give rise to?
central arterioles
How do the majority of central arterioles end?
in cords
What are cords?
lack an endothelial lining and form an open blood system
what cells line the cords?
fibroblasts and macrophages
How does blood re-enter the circulation after passing through the cords?
crosses into the venous sinuses
What do the cords and sinuses collectively form?
red pulp
What lies directly around the central arterioles?
periarteriolar lymphatic sheath
what is the periarteriolar lymphatic sheath equivalent to in the lymph node?
T zone
What is foudn adjacent to the PALS?
B cell follicles
What surrounds the B cell follicles in the spleen?
marginal and perifollicular zones
what is found in the marginal and perifollicular zones?
macrophages and dendritic cells
What can be seen on blood film with splenic atrophy?
Howell-Jolly bodies (nuclear remnants); siderotic granules (pappenheimer bodies); misshapen cells
What is the B-cell receptor?
a membrane-bound immunoglobulin and binds to a specific antigen
What does binding of the B-cell receptor cause?
activationg of PI3K-production of PIP3 and activation of Bruton tyrosine kinase to induce AKT (anti-apoptotic, pro-survival kinase)
What are the two types of T cell antigen receptor heterodimers?
alpha-beta or gamma-delta
What are NK cells?
cytotoxic CD8 cells which lack the T cell receptor
What surface molecules do NK cells typically express?
CD16 (Fc receptor); CD56 and CD57
What surface molecules do B cells typically express?
CD19 and CD20
What surface molecules do T cell typically express?
CD3 and CD7
what is the difference between B cells foudn in germinal centre/follicle compared to their surrounding mantle zone?
more mature B cells are foundi nthe mantel zone
What is the function of NK cells?
kill target cells that have a low expression of HLA class I eg viral infection of malignant cells
What surface marker is foudn on pre-B cells?
CD9
What surface marker is found on precurosr B cells?
CD10
What is the antigen binding immunoglobulin on B cells associated with?
CD79
What are the leukaemias characterised by?
accumulation of malignant white blood cells in the bone marrow and blood
