Term
| What are the 3 T cell antigen processing pathways? What types of antigens do they present, what MHC molecule do they use and what type of T cell do they activate |
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Definition
Endogenous pathway
-intracellular proteins loaded onto MHC I (viruses, cancer cells)
-CD8 cells
Exogenous
-peptides from extracellular proteins (bacteria) loaded onto MHC Class II
-CD4 T cells
Cross-presentation
-endogenous antigens taken up by an APC and presented as MHC Class I
-CD8 cells |
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Term
| Anatomical location of T cell maturation |
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Definition
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Term
| What phenotypic marker is unique to vet species, what T cell subset expresses it |
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Definition
marker: WC1
expressed on gamma/delta T cells which are primarily found in the skin & mucosal surfaces |
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Term
| What other cells express CD4 in dogs? |
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Definition
| T cells, neutrophils and macrophages all express this marker in dogs |
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Term
| Components of immunological synapse |
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Definition
| T cell receptor + antigen + MHC I/II |
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Term
| 2 signals required to activate T cells |
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Definition
-formation of trimolecualr complex
-costimulation |
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Term
| Targets of CD4 & CD8 T cells |
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Definition
CD4 binds MHC Class II - kills bacteria
CD8 binds MHC Class I - kills viruses |
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Term
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Definition
-Perforin punches holes in cell mmb
-Granzymes trigger caspase cascade leading to apoptosis
-Fas/Fasl pathway triggers caspase cascade leading to apoptosis |
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Term
| Why can a superantigen trigger toxic cytokine storms |
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Definition
T cell superantigen = mitogen that non specifically links MHC on an APC and T cell receptor on a T cell
-bypasses the classical antigen presentation pathway, so lots of T cells are activated
T cells produce IFN-gamma which activates macrophages to produce IL-1, IL-6 and TNF-alpha. All are toxic, but TNF alpha especially |
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Term
INDEPENDENT STUDY THING MAY BE ON EXAM
|||Which vet won nobel prize in phys/med
What was their field of expeertise
What scientific finding earned the reward? |
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Definition
Peter Doherty - immunology
Discovered how T cells recognize cells that are infected by viruses (histocompatability antigens) |
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Term
| Which T cell types are classified as helper T cells? Why? |
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Definition
| CD4 - they secrete cytokines to activate other effector cells |
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