Page 94 - Teknik Menjawab Soalan PSPM Biologi

immunity

Cell mediated immune response

- Macrophage engulf antigen by phagocytosis

- fragments of antigen is displayed on the cell surface

together with a class II MHC

- Formed class II MHC- antigen complex , macrophage

known as antigen presenting cell (APC)

- APC secrete IL-1 which activates TH cell secrete IL-2

- Antigen also infected body cells, fragment of antigen is

displayed on the cell surface together with class I MHC

- Formed class I MHC-antigen complex
- Tc cell binds to the complex on infected cell

- TH cell secrete IL-2 that activated the Tc cell to proliferate

and diffentiate into activated Tc clone and memory Tc clone
- IL-2 stimulate activated Tc cell to release perforin and

granzymes which form pores in the infected cell’s membrane

- The cell lyse