Term
| What is the most common portal of entry for organisms? |
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Definition
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Term
| What recognizes antigens and initiates the immune response in the MALT? |
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Definition
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Term
| How is an antigen recognized and an immune response initiated in the GALT? |
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Definition
| M (microfold cells) facilitate antigen uptake in the gut and release it to dendritic cells |
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Term
| What effect do TLR ligands and enterotoxins have on intestinal epithelium? |
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Definition
| They stimulate chemokine release from epithelial cells to attract more dendritic cells to the site |
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Term
| How do normal gut flora interact with pathogens? |
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Definition
| They provide competition and make it difficult for pathogens to gain entry. They can, however, be killed by antibiotics and provide a foothold for foreign bacteria to cause injury |
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Term
| What is the protective layer against bacteria in the gut? |
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Definition
| Polymeric IgA binds to the mucus layer overlying the epithelium. It is able to adhere and resist protease activity due to its secretory component, and acts to neutralize pathogens and their toxins |
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Term
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Definition
| Protein associated molecular patterns that provide danger signals to warn of a pathogen |
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Term
| What happens to an epithelial cell once it has been infected? |
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Definition
| It expresses two atypical class I molecules (MIC-A and MIC-B) which are recognized by gamma-delta T cells bearing the NK receptor NKG2D and subsequently killed. |
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Term
| What is a likely mechanism for tolerance to food antigens? |
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Definition
| Action of Tregs prevents activation and action of T cells against food antigens |
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