Term
| What are the eight chains of the TCR? |
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Definition
(1) alpha chain
(2) beta chain
(3) and (4) two zeta chains
two CD 3 receptors containing (5) and (6) two epsilon chains and (7) and (8)two gamma or delta chains |
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Term
| What is the function of the alpha and beta chains of the TCR? |
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Definition
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Term
| What is the function of the two zeta chains in the TCR? |
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Definition
| they are are intracellular, they transmit a signal for a intracellular signal cascade |
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Term
| What is the function of the two CD3 receptors within the TCR? |
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Definition
| form a stable interaction with the TCR |
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Term
| Role of T helper cell in immune responses? |
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Definition
| o Helper cells function to have cytokine-mediated regulatory function, they regulate up-regulation of the immune system which leads to eradication of the pathogenic organisms by phagocytes |
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Term
| Role of cytotoxic T cells in immune responses? |
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Definition
| Cytotoxic T cells kill the infected cells with intracellular pathogens |
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Term
| Positive selection in T cells versus B Cells |
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Definition
| Positive selection occurs in the thymus (as opposed to bone marrow) and produces single positive T cells |
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Term
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Definition
| combinations of V,D and J genes produce diverstiy in T cells |
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Term
| generation of juntional diversity |
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Definition
| Addition of P and N nucleotides to the hypervariable region of the receptor |
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Term
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Definition
| pre-t cells develop into DP thymocytes. Successful rearrangement of the β chains induce the pre-t cell to stop gene rearrangements and down regulate RAG protein |
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Term
| steps in T cell maturation |
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Definition
(1)Construction of T cell receptors in thymus
(2) selection of those receptors which can recognize and bind self MHC molecules, generates single positive T cells
(3) Self receptors are eliminated by negative selection
(4) Central tolerance of self receptors
(5) Peripheral tolerance by Treg cells |
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Term
| Functions of Thymus in T cell development |
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Definition
(1)Thymus provides epithelial cells for the T cell receptors to bind to- positive selection
(2)Provides Dendritic cells for negative selection |
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Term
| Role of epithelial cells in T cell development |
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Definition
| Epithelial cells function in positive selection (strongest survive) |
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Term
| Role of dendritic cells in T cell development |
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Definition
| Dendritic cells function in negative selection (strongest die) |
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Term
| Functions of the T regulatory cell |
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Definition
(1) peripheral tolerance
(2) Suppressive function |
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