Term
Class I loci
Class II loci
(which has loci subset?)
What chromosome is the MHC located on in humans? |
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Definition
Class I: HLA-A, HLA-B, HLA-C
Class II: HLA D
Subsets: DR, DQ, DP
Chromosome 6
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Term
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Definition
| - genes that happen to reside in the MHC region but do not present antigen to T-lymphocytes |
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Term
| Structure of MHC class I molecules (size, what other molecules do they associate with?) |
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Definition
- each loci encodes for a polypeptide chain with MW of about 44,000.
- on cell membranes these chains are associated non-covalently with a lighter chain, b2 microglobin (12,000 daltons), coded for by another chromosome |
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Term
| Number of domains of MHC I alpha chain, function of each? |
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Definition
3 alpha domains -
alpha 1 and 2 make up edges of binding cleft
- alpha 3 and B2 microglobin support binding cleft |
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Term
which chain of the MCH class I is the antigen determinant?
Which chain is the same in all MHC class I molecules? |
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Definition
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Term
Structure of MCH class II
-how many chains?
-size?
- How many domains does each chain have?
- Which ones bind antigen? |
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Definition
- two chains, alpha and beta
- entire chain is about 60,000 daltons
- each have 2 domains
-alpha 1 and beta 1 bind antigen |
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Term
| compare MCH I and MHC II in terms of the size of peptide they bind? |
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Definition
| - MHC class I molecules bind peptides slightly longer (13-17 aa's long) |
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Term
| What does association of MHC class I with B2 microglobulin allow for? |
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Definition
| Transport to cell surface |
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Term
What are anchor amino acids?
How many anchor sequences do peptides associating with Class I molecules have?
How many anchor sequences do peptides associating with Class II molecules have? |
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Definition
- amino acids on peptide that allows it to bind to class I and class II
- class I: one, mostly tyrosine
class II: four anchor sequences |
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Term
| What is the inheritance pattern for MHC? |
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Definition
- co dominance
- e.g. 3 MHC class I from mom, 3 MHC class I from dad. |
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Term
| Why choose same sex for organ donation if possible? |
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Definition
| - males encode for antigens that females do not |
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Term
| MHC molecules are highly polymorphic. Which locus is the only one that is not? |
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Definition
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Term
| Where is the main polymorphism in MCH molecules? |
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Definition
| - in peptide binding groove |
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Term
| what is T-cell MHC restriction? |
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Definition
| - dependence of T-cells specific reactivity on foreign antigen plus MHC products rather than on foreign antigen alone |
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Term
| What on the T-cell recognizes the MHC + antien? |
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Definition
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