fighting infection- virus' Flashcards
virus’ enter host cells and
replicate
host cells will release
IFN-alpha
IFN-alpha released by host cells causes
host cells to diplsay part of the viral peptide on their surface MHC 1 molecule.
IFN-alpha also
prevents neighbouring cells from getting infected
when virus kills infected cell
viral particles are released and activate dendritic cells, which engulf particle
- dendritic cells transport particles to the local lymph nodes via lymphatic system
dendritic cells enter the lymph system and cause
naive T cells to enter
interaction between dendritic cells and naive t cell
dendritic cells present viral peptides to T helper cells on their MHC II molecules which activate T cells
dendritic cells can activate
Th1 and Th2 cells
activated Th2 cells
cause B cells to become plasma cells and release antibodies
how are B cells activated by T cells
via co-stimulatory molecules and the release of cytokines
Th1 cells activate..
cytotoxic T cells
how are cytotoxic T cells activated
by Th1 cells which release cytokines - IFN-gamma and IL-2)
Th1 and cytotoxic T cells leave
the lymph node and of to the site of infection
virally infected cells are killed by
cytotoxic T cells –> they used MHC I molecules which present on virally infected cells to be recognised
NK cells get activated by
IFN-alpha released by infected cells and IL-2 and IFN-gamma, released by T helper 1 cells –> once activated NK cells kill virally infected cells