B1 anatomy of immunity Flashcards
anatomy of immunity
the life of a t cell
-selected in thymus
-matures and migrates into the periphery
-circulates through lymph nodes
-if it recognises antigen, activates effector function
peripheral lymphoid organs
adenoid
tonsil
right subclavian vein
left subclavian vein
thymus
lymph node
heart
thoracic duct
kidney
spleen
peyers patch in small intestine
large intestine
appendix
bone marrow
lymphatics
what happens when T cell enter lymph node cortex
enter lymph node cortex from blood via high endothelial venules (HEVs)
T cells not activated by antigen presented by dendritic cells exit from lymph node via cortical sinuses
-migrate through secondary tissues
-sample peptide:MHC complexes on dendritic cells
3 stages of lymphocytes and how they respond to antigen in peri lymphoid organs
-naive lymphocytes enter lymph nodes from blood
-antigens from sites of infection reach lymph nodes via lymphatics
-lymphocytes and lymph return to blood via the thoracic duct
T cell receptor function
-2 protein chains paired together
often α and β
Sometimes γ and δ
-variable regions
recognises diversity
-transmembrane with cytoplasmic tail
signlling upon recognition
what happens if t cell recognises antigen MHC
-t cell and antigen presenting cell form interaction
-tcr transmits signals and t cell becomes activated
the 3rd and 4th dimension?
-adaptive immune system takes time to respond
-immune responses occur in diff locations
-requires cells to move, interact and produce cytokines to influence effector function