- Cytosolic pathogens: - Where are they degraded? - What do their peptides bind to? - What kind of cells do they present to? - What is the effect on the presenting cell? - Intravesicular pathogens: - Where are they degraded? - What do their peptides bind to? - What kind of cells do they present to? - What is the effect on the presenting cell? - Extracellular pathogens and toxins: - Where are they degraded? - What do their peptides bind to? - What kind of cells do they present to? - What is the effect on the presenting cell.