The Major Histocompatibility Complex -Hudig Flashcards
(blank) is often associated with HLA B27
Immobility/consolidation with inflammation of the vertebrae
Ankylosing Spondylitis
What do you call the allelic differences among MHC genes in human?
HLA
T or F, the very same proteins that prevent transplantation are the proteins that present foreign peptide antigens to T cells.
T
What is this:
a site on a chromosome where a gene is located
gene locus
What do you call a site on a chromosome where a gene is located?
gene locus
What is this:
variant forms of a gene that occupy one gene locus
alleles
I.e HLA-A11 is an allele of HLA-A locus. HLA-A34 is another allele
What makes up a MHC class I protein?
MHC class I alpha + beta2microglobulin
What is this:
a protein associated with MHC 1 proteins, gene outside MHC complex
Beta2 microglobulin
What makes up a MHC class II proteins?
MHC class II alpha and beta protein chains
The human major histocompatibility complex (MHC) is a large multigene complex on chromosome (blank)
6
There are (blank) classes of MHC (HLA) genes, all of which are found on chromosome 6. What are they?
3 MHC class I MHC class II MHC class III
Which 2 MHC class proteins are multi-genic?
1/2
What does multigenic mean?
that there is more than 1 locus
What are the three loci that MHC class 1 have?
A - 800+ alleles
B – 1400+ alleles
C – 500 + alleles
Are CD1 proteins MHC proteins?
nope
What is the structure of MHC class 2 proteins? Since MHC Class II proteins are multigenic, what are its loci?
class 2 alpha chain class 2 beta chain • 3 loci o DP One beta one alpha o DQ One beta one alpha o DR Two beta one alpha
Does MHC get inherited with crossing over?
no!
What is this:
pretty invarient, few alleles, complement C2, C4, TNF alpha are here
MHC class III
Which MHC classes are recognized as not self when transplanted w/in one species?
CLass 1 and 2
What does multiallelic mean?
many alleles for a single locus in a population
What does polymorphic mean
many alleles frequently used in the population
WHat does multigenic mean?
more than one locus for the family of proteins (e.g HLA class I A,B and C are different genes)
(blank) is multiallelic, multigenic, and expressed co-dominantly
MHC class I
Everyone pretty much as the same (blank) and very differen MHC class I and 2
MHC class 3
What is an antigenic MHC?
it is when an MHC gets transplanted into someone else and it is not an exact match so it is considered an antigen
Each MHC allele can bind thousands of different (blank) because of their different shaped clefts
peptides
The MHC class I (blank) chain forms a peptide-binding cleft.
Alpha
THe MHC class I cleft holds on (blank) long peptides
9-11 AA
Each MHC allelic protein will hold (the same/ different) peptides
different
Peptides larger than 11 AAs will not fit in the (blank) clefts
MHC1 clefts
The peptides fit into the MHC1 cleft by (blank) anchoring of several amino acids of the peptides into the cleft.
non-covalent
MHC I allelic variation maximizes antigenic peptide presentation in the human population. T or F
T
A person who inherited MHC I alleles that are unable to bind any influenze peptids is (blank)
SOL re flu
(blank) proteins are always present on APCs, missing on other cells and inducible (by gamma interferon) in endothelial cels during inflammation
MHC class II
MHC II is open ended and can hold (blank) peptides
large
MHC Class II is also (blank) and (blank)
multigenic and multiallelic
What are the 3 MHC II genes?
HLA-DP, HLA-DQ, HLA-DR
What is a butterfly rash indicative of?
Systemic Lupus Erythematosus (SLE) patients
MHC (blank) proteins are found on; T cells, B Cells, Macrophages, other APCs, epithelial cells of the thymus, neutrophils, hepatocytes, kidney, and brain cells.
MHC (blank) proteins are found on; T cells, B cells, macrophages, other APCs and epithelial cells of the thymus (They are not on neutrophils, hepatocytes, kidney or brain cells. )
class I class II
What HLA allele is associated with ankylosing spondylitis?
B27
What HLA allele is associated with Type I diabetes?
DR3, DR4, DQ8
What HLA allele is associatd with systemic lupus erythematosis?
DR2
Why are MHC I and MHC II barriers to organ transplantation?
MHC I and MHC II antigens are too well recognized and provoke adaptive immunity in pnt
Mismatch of ABO blood group antigens (»» HLA class II > HLA class I»_space;minor histocompatibility antigens
)
What is an autograft?
tissue grafted within one person, or between genetically identical mice or twin (100% successful)
What is an allograft?
tisue grafted between HLA (& other loci) alogeneic individuals (usually rejected within 2 weeks w/out immunosuppression)
Graft rejection is caused by T cells responding to (blanK)
alloantigens (foreign antigens)
If you have complete HLA matching will your graft work perfectly?
no because there are still other genetic differences that support graft rejection
(blank) have a high frequency of recognition of foreign MHC molecule, greater than the frequency of responses to self MHC and a foreign peptide antigen.
T cell receptors
THe MHC III genes are mostly (blank)
nonallelic :)
What are haplotypes?
linked sets of genes usually inherited as one unit
How are haplotypes inherited?
one from each parent :)
Each person has 2 chromosome 6s and 2 MHC halotypes
:) T or F
Truth
HLA haplotypes are usually inherited as a (blank)
single unit
(blank) are made by several bacteria including staph which produce the superantigens (blank) and (Blank)
enterotoxin
toxic shock syndrome
Why do we call some antigens superantigens?
Because they bind to a very large number of T cells and trigger massive T cell responses
Superantigens bind to 2 sites simultaneously, what are they?
MHCII chains and TCR VbetaS
What is Vbeta2?
It is part of the receptor encoded by one of the V minigenes of the TCR beta chain.
Superantigens bypass normal MHC II antigen presentation. How do they bind instead?
Bind to MHC II outside the peptide-binding groove
Do superantigens need to bind a foreign antigen in MHC II and have their peptides processed to be recognized?
no, instead they bind to TCV vbetas.
How many superantigens can bind to a certain TCR VbetaS?
one
What does the cytokine release caused by superantigens cause?
toxic shock syndrome and staph food poisoning
What causes rapid food poisoning?
the superantigen staphylococci enterotoxin
Superantigens cause a whirlwind release of cytokines, what are these?
IFN gamma, TH1 cells (which increases production of IL-1 from the macrophages)
Diarrheal diseases account for approx. 2 milllion deaths/year among children less than 5. (2nd most common cause of child deaths worldwide)
THis is caused by (Blank)
superantigens