Third Line of Defence - T-cell Response

Question 1

Explain 1st stage in T-cell Response

Answer 1

Virus particles infect our body and are engulfed by phagocytes. Viral antigens are presented on MHC-2

Question 2

Explain 2nd stage in T-cell Response

Answer 2

A specific T-helper cell with a unique, complementary receptor binds to viral antigen. Cytokines are released.

Question 3

Explain 3rd stage in T-cell Response

Answer 3

The virus infects body cells and causes it only to produce viral proteins which is displayed on MHC-1

Question 4

Explain 4th stage in T-cell Response

Answer 4

A Cytotoxic T-cell with unique, complementary receptor binds to viral antigen. When cytokines bind to it, it divides rapidly.

Question 5

Explain 5th stage in T-cell Response

Answer 5

Lots of identical Cytotoxic T-cells are produced which destroy infected body cells

Question 6

Explain 6th stage in T-cell Response

Answer 6

Memory T-cells are formed. If the same viral antigen is detected, they rapidly divide into lots of cytotoxic T-cells and more memory t-cells. The cytotoxic T-cells destroy the virus before lots of cells are damaged. No symptoms develop - you are immune!

Question 7

Explain how Cytotoxic T-cells function

Answer 7

Cytotoic T-cells release vesicle containing granzyme and perforin which destroys the cell and the viral particles inside.