Term
| What are the two processes involved in the destruction of intracellular bugs? |
|
Definition
| Phagocytic and Non-Phagocytic |
|
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Term
| What do the phagocytic cells attack during intracellular bug infestation? |
|
Definition
| intracellular bacteria. Fungi. Protozoa. |
|
|
Term
| What do the phagocytic cells attack during extracellular bug infestation? |
|
Definition
| Viruses, Ricksettsiae...and some types of protozoa. Done by destroying the cells which harbor the pathogen. |
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Term
| what do you call a cell that has left the thymus and has yet to encounter an antigen? |
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Definition
|
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Term
| what needs to happen when a naive T cell encounters a microbial antigen? |
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Definition
| 1) the number of antigen-specific cells needs to increase. 2) Naive T cells become "armed" effector T cells. |
|
|
Term
| which cells present antigen to naive T cells? which of these cells is the strongest activator of naive T cells? |
|
Definition
| Macrophages, B cells, and Dendritic Cells (strongest) |
|
|
Term
| what is so special about APCs that they can turn a naive T cell into an effector T cell? |
|
Definition
| they express a co-stimulatory molecule known as B7 |
|
|
Term
| what happens when activation of a T cell occurs? |
|
Definition
| 1) cytokines are secreted. 2) Cytokine receptor expression. |
|
|
Term
| what is the first key step in T cell activation? |
|
Definition
| Interleukin 2 (cytokine) is secreted and binds to IL-2 receptor. |
|
|
Term
| what is the function of IL-2? |
|
Definition
|
|
Term
| what is "differentiation" in a T cell response? |
|
Definition
| develop a phenotype that allows a function such as "effector cells" and "memory cells" |
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|
Term
| name two Co-Receptor molecules, and what do they do? |
|
Definition
| CD4 and CD8. stabilize interaction between T cell receptor and peptide/MHC complex |
|
|
Term
| which class of MHC does CD4 recognize? |
|
Definition
|
|
Term
| which class of MHC does CD8 recognize? |
|
Definition
|
|
Term
| T/F: the CD4/8 recognition of the MHC molecule occurs in the peptide binding cleft. |
|
Definition
| False. this cleft is reserved for peptide and MHC class I/II |
|
|
Term
| what is the major function of CD4+ T cells? |
|
Definition
| cytokine producing helper cells |
|
|
Term
| what is the major function of CD8+ T cells? |
|
Definition
|
|
Term
| what is the minimum number of T cell receptors needed for antigen recognition? |
|
Definition
| at least two. and it could need to hang onto the cell on the order of minutes to hours to days. |
|
|
Term
| T/F: the TCR provides the necessary signaling to activate a T cell. |
|
Definition
| False. mediated by different molecules such as a CD3 complex (Gamma, delta, epsilon chains). |
|
|
Term
| what does Muromorab (drug) do? |
|
Definition
| it reacts with the epsilon chain of the CD3 complex and blocks it. Thereby blocking the function of T cells and can help reduce acute allograft rejection in transplant patients (its just an immunosuppressant). |
|
|
Term
| what else helps the binding of a TCR with antigen? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| what do chemokines do to LFA-1 affinity and clustering? |
|
Definition
| increases them so you get a much tighter bond between T cell and APC, thus provoking T cell activation. |
|
|
Term
| In general, how do integrins help TCR-peptide/MHC interactions? |
|
Definition
| increase the number and length of interactions. |
|
|
Term
| what is the first signal in T cell activation? |
|
Definition
|
|
Term
| what is the second signal in t cell activation? |
|
Definition
|
|
Term
| what are three examples of co-stimulatory molecules? |
|
Definition
|
|
Term
| T/F: components of innate immune response can increase expression of B7.1 and B7.2 |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| binds to CD40L on T cells |
|
|
Term
| what does CD40 do once bound? |
|
Definition
| increases expression of B7 and IL-12 secretion (help activate T cells) |
|
|
Term
| what is the defining feature of a professional APC? |
|
Definition
| the ability to express co-stimulatory molecules |
|
|
Term
| what is cross-presentation? |
|
Definition
| antigen that has been chopped up into peptides in another cell and is presented on dendritic cells |
|
|
Term
| T/F: CD8+ T cells need activation of CD4+ T helper cells to become activated. |
|
Definition
| True. because these T helper cells can make cytokines which can help drive activation. |
|
|
Term
| Where does the "near-ness" of CD4+ and CD8+ T cells take place? |
|
Definition
| secondary lymphoid tissues. |
|
|
Term
| HIV destroys which T cells? |
|
Definition
|
|
Term
| why do infected people have defective CD8+ CTL responses? |
|
Definition
| The need for CD4+ T cell help to generate CD8+ CTL responses. |
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Term
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Definition
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