C HLA

Question 1

What does HLA class I molecules do

Answer 1

Restrict CD8+ function & mediate immune responses against ‘endogenous’
antigens & virally infected targets

Question 2

What does HLA class II molecules do

Answer 2

involved in the presentation of ‘exogenous’ antigens to T helper cells

Question 3

What does HLA class III molecules do

Answer 3

Contains genes encoding proteins that are unrelated to cell-mediated immunity but modulate/ regulate immune responses e.g. TNF, HSP & complement proteins: C2, C4

Question 4

What are the class Ia HLA 
class Ib

Answer 4

HLA-A,B,C
(Highly polymorphic, with many alleles)

Class Ib = HLA-E,F,G
(Few variants of gene)

Question 5

Describe Class II HLA

Answer 5

Class II are not translated in human trophoblast cells even under inducing conditions.

Question 6

Which cell control expression of HLA genes and proteins

Answer 6

Strictly Trophoblasts: recognition by maternal immune cells may trigger anti-fetal cytotoxic Tc responses against HLA-expressing fetal cells