Term
| Central tolerance - anatomical location, positive/negative selection |
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Definition
Killing off self-reactive T cells, happens in the thymus
First test is to see if the cell reacts strongly to self antigens. Yes? killed. No? go to step 2. (negative selection)
Next, see if it reacts with self-MHC. No? killed. Yes? Will be allowed to proliferate. |
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Term
| What happens if an immunological synapse is formed but there is no co-stimulation |
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Definition
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Term
| What is an immune checkpoint |
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Definition
| CTLA-4 shuts off T cell responses |
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Term
| How do Tregs suppress immune responses |
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Definition
| Produce TGF-beta, IL-10 and IL-35 which suppress T cell activity |
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Term
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Definition
| secrete IL-17 to promote innate immune response |
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Term
| How can helper-dependent antibody responses be tolerized |
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Definition
| administer very low or very high doses of antigen, this induces peripheral tolerance |
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Term
| How do Abs suppress B cell responses |
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Definition
binding to inhibitory B-cell receptors such as CD32b
IgG antibodies suppress both IgM and IgG production
IgM antibodies only suppress IgM production |
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Term
| What are the drawbacks to passive transfer of immunity in newborns? |
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Definition
| can delay the neonate's production of immunoglobulins, reducing vaccine efficacy (this is why we don't vaccinate right at birth) |
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Term
| Why are Abs produced by myelomas likely to make a patient susceptible to infection |
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Definition
| Myelomas produce large amounts of antibodies, which has a negative feedback effect on B cell responses (less antibodies being produced by the patient themself) = suppressed immune system |
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Term
| What is hemolytic disease? Prevention? |
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Definition
1. Mom: Rh-. First child: Rh+. Mom acquires some Rh+ antibodies at birth.
2. Second child is Rh+, but mom's antibodies will cross placenta and target offspring's red blood cells.
Prevention: give antibodies against antigen at birth of first child, so that she does not develop her own Rh antibodies. |
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Term
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Definition
alveolar macrophages
-involved with tolerance, important in the lungs otherwise you'd have chronic inflammation with every new thing you breathe in |
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Term
| What effect does antigen presentation by an immature dendritic cell have on a T cell? |
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Definition
| cause them to become Tregs (produce Il 10, Il 35, TGF-beta) which suppresses activity to promote tolerance |
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Term
| How does IDO regulate T cell responses? |
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Definition
| Depletes tryptophan which is essential for T cells to survive |
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Term
| What immunological concept explains the link between stress and immunity |
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Definition
| short-term stress enhances the immune reponse, long-term stress suppresses it |
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Term
| Know the 4 examples of immunoprivileged sites |
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Definition
Brain
Eyes
Testicles/ovaries
Placenta/fetus |
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