Linking Innate and Adaptive immunity - 33 Flashcards
How do dendrites transport bacteria to communicate with adaptive arm
Detect bacteria
Form phagosome with bacteria
Drain through lymphatic system into lymph to activate T-cells and B-cells
What is the basic function of B-cells
Make antibodies (Y shaped molecules) helps to target for phagocytosis.
What is the basic function of T-cells
Cytotoxic T-cells. Either stimulates other cells or sends death signals to infected cells.
How do dendritic cells present antigen to T-cells
Process it down to peptides (chain of amino acid approx. 8-30 long) and present on MHC
What is the MHC
Major Histocompatibility Complex
What are the 2 types of T-Cells
CD4 - (Cytokines) Helps stimulate B-cell to make antibodies and CD8 cells become Cytotoxic
CD8 - Becomes Cytotoxic and kills infected cells
What do B-cells do
Differentiate into plasma (with help of CD4) and produces antibodies
How do CD4 cells interact with MHC
TCR receptor on surface of CD4 cell. CD4 co-receptor binds to MHC 2
How do CD8 cells interact with MHC
TCR receptors on surface of CD8 cell. CD8 co-receptor binds to MGC-1
What is an antigen
Anything able to be recognised by immune system.
Foreign when anything ‘outside’ body
Auto (self) antigens
How did adaptive immunity evolve
500 million years ago in vertebrates.
What does MHC-1 present
Presents endogenous (intercellular) antigen
What does MHC-2 present
Presents exogenous (extracellular) antgens
Explain Endogenous and examples
Inside cell - broken down in cytoplasm, sent to ER and transported to MHC-1 receptors on cell surface. On all cells with nucleus. Viruses
Explain exogenous and examples
Broken down in phagolysosome. Loaded into MHC-2 receptors on surface of cell. Activates CD4 cells. Phagocytic Bacteria and viruses.