Lecture 16: Immune activation, Helper cells and regulation Flashcards
1
Q
What kind of cells express class II MHC involved in the exogenous pathway?
A
B cells and specialised APCs
2
Q
Features of Class II MHC?
A
- Codominant (both parents expressed)
- polymorphic
- present peptides to CD4 T cells
3
Q
features of Class I MHC?
A
- Found on virtually all nucleated cells
- co dominant
- polymorphic
- Present peptides to CD8 cells
4
Q
T cell antigen recognition
A
HLA 1: Bind to T cell receptor with help of CD8 binding to area on HLA-a,b or c. CD3 activated following binding. T killer cells.
HLA 2: Bind to TCR on helper cell with aid of CD4 binding to area on HLA DP,DQ or DR. CD3 transduces signal to say binding has occurred.
5
Q
Summary of patient with defect in TAP genes
A
A transporter gene involved in moving class 1 HLA to surface (endogenous path)
Defect means low HLA-A,B or C expression, low CD8 T cells, normal CD4. Recurrent resp viral infections. Meaning HLA 1 needed for CD8 T cell development.
