Term
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Definition
| making contact with other cells |
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Term
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Definition
-clonally distributed (each t cell has its own specific receptor)
-MHC restricted
-specific for a single antigen/epitope |
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Term
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Definition
-segregates Ag recognition and signal transduction
-CD3 requires for TCR surface expansion |
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Term
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Definition
-not invovled in Ag recognition
-2nd signal
-adhesion proteins (homing, immunological synapse) |
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Term
| antigen recognition by t cells |
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Definition
-recognized peptides displayed by MHC
-recognition of peptide:MHC complex by V alpha and V beta chain
-unique specificity for a single epitope
-signal transduction |
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Term
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Definition
-heterdimeric (alpha and betsa)
-not produced in secreted form
-does not undergo changes in constant region or affinity maturation
-binding resion structurally similar to Fab of Ig |
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Term
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Definition
| -membrane bound Fab fragment |
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Term
| TCR verusus Ig: Ag recognition |
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Definition
-CDRs participate in antigen:MHC recognition
-TCR can only recognize peptide antigens in association with MHC molecules |
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Term
| Antigen receptor properties |
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Definition
-peptides displayed by MHC molecules on APCs and linear epitopes
-each clone unique specificity:potential for greater than 10^11 specificities
-antigen recognition is mediated by variable regions of alpha and beta chains
-does not perform effector functions |
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Term
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Definition
-precursors migrate from bone marrow to thymus to mature
-commitment, rearrangement, selection
-proliferation/differentiation |
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Term
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Definition
-TCR gene expression occurs during t cell development
-alpha and beta chains are expressed separately and come together to form membrane bound TCR
-generates the large repertoire of TCR diversity (up to 10^6 different TCRs) |
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Term
| organization of TCR genes |
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Definition
-made up of multiple copies of V, (D), J gene segments
-large number of variable gene exons contained within genetic loci |
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Term
| recombination of VD and J segments coordinated by |
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Definition
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Term
| origin of t cell receptor diversity |
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Definition
-combination of gene segments
-multiple gene segments
-junctional diversities +/- nucleotides
-alpha beta chain association |
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Term
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Definition
| -number of possible VDJ combinations |
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Term
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Definition
| total potential repertoire with junctional diversity |
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Term
| stages in t cell development |
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Definition
-stem cell
-pro T (double negative)
-pre T (double negative)
-double positive
-single positive |
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Term
| pre T cell (double negative) |
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Definition
-express of a productive b chain gene segment
-VDJ gene segment rearrangement
-beta chain associated with pre-T alpha chain (identical in all pre T cells)
-allelic exclusion (inhibition of further beta-chain gene arrangement)
-expression of CD3 complex and zeta chain (mediate survival signals) |
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Term
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Definition
-express both CD4 and CD8 co receptor
-expression of productive alpha (VDJ-C) beta(VJ-C) chains
-express chemokine receptor (CCR7) improtant for secondary lymphoid
-responsive to Ag
-must go through selection before leaving thymus |
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Term
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Definition
-occurs at double positive stage
-t cells must recognize self MHC
-low avidity binding of TCR to self peptide:self-MHC lead to survival signals
-encounter self peptides displayed on self MHC mainly on cortical thymic epithelial cells and dendritic cells
-ensures TCR is MHC restricted
-determines expression of either CD4 or CD8
-not known what signals protect from death |
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Term
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Definition
-occurs at double positive and single positive stage
-t cells much not recognize self antigens
-hgih avidity of TCR to self peptide:self MHC are deleted
-tissue specific proteins are expressed in the thymus and participate in negative selection (transcription factor AIRE (autoimmune regulator))
-encounter self peptides displayed on self MHC on medullary thymic epithelial cells and dendritic cells
-mechanism to maintain central and tolerance (self tolerance) |
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Term
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Definition
| selects for productive B chain |
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Term
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Definition
| selects for productive alpha chain |
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