Human Leukoctye Anitgen and Tissue Typing

Question 1

Where are MHC I receptors found?

Answer 1

On all nucleated cells

Question 2

Where are MHC II receptors found?

Answer 2

Macrophages
Dendritic cells
B lymphocytes

Question 3

What is the structure of MHC I receptors?

Answer 3

Alpha 1 and 2 chains at distal end

Beta 1 and alpha 3 chains at proximal end

Question 4

What is the structure of MHC II receptors?

Answer 4

Alpha 1 and beta 1 chains at distal end

Alpha 2 and beta 2 chain at proximal end

Question 5

What do MHC I receptors bind to? Why?

Answer 5

CD8+

Alpha 3 is coreceptor

Question 6

What do MHC II receptors bind to? Why?

Answer 6

CD4+

Beta 2 is coreceptor

Question 7

What does it mean that MHC molecules are codominantly expressed?

Answer 7

Alleles from each parent are expressed equally

Question 8

What does a haplotype mean?

Answer 8

That MHC alleles are inherited as a set on each chromosome

Question 9

Three polymorphisms of MHC I:

Answer 9

HLA-A
HLA-B
HLA-C

Question 10

Four polymorphisms of MHC II:

Answer 10

HLA-DP
HLA-DQ
HLA-DR alpha
HLA-DR beta

Question 11

What is critical in solid organ transplants?

Answer 11

Making sure the patient has not made antibodies against the donors antigens

Question 12

What are three components of HLA testing for transplants?

Answer 12

1. ) HLA typing of donors and patients
2. ) HLA antibody screening of patients
3. ) Lymphocyte cross-matching (donor only) after the match is found

Question 13

What are three ways patients can form antibodies against the donor?

Answer 13

1. ) Multiple pregnancies from exposure to the fathers HLA
2. ) Blood or platelet formation
3. ) Previous organ transplants

Question 14

What does lymphocyte cross-matching look for?

Answer 14

Tests to see if the donors lymphocytes have antibodies directed against the patients serum