Immunity to Tumors 1 Flashcards
How does the immune system prevent tumors
eliminate oncoviruses, prevent establishment of inflammatory envionment, identify and eliminate tumor cells on the basis of their expression of tumor-specifc antigens
What are the three steps in cancer immunoediting
elimination, equilibrium, escape
T/F: Immune compromised individuals have a higher risk for cancer
True
What two factors can cause earlier and aggressive cancers
immune-system deficiency and genetic predisposition to cancer
What are the three possible outcomes for tumor cells in the equillibrium stage
eradicated, persist but not progress, escape
How are ways mutations can keep tumor cells alive
evasion of recognition, killing or control by the immune system
What features of an immunosuppressive tumor microenvironment
tumor cells inhibit the function of effector immune cells, recruit regulatory immune cells
Where is CD28 located,B7
T cell, Target cell
What are outcomes of TCR antigen binding
transcirptional regulation, cytokine expression, cell proliferation, cell killing
What are the inhibitory checkpoint molecules
PD1 and CTLA-4
How dose the PD-1/PD-L1 pathway inhibit
prevents excessive stimulation and maintains the immune tolerance to self-antigens through negatively regulating the immune response
How does the CTLA-4 pathway inhibit
Has a greater affinity than Cd28, modulate activation through a series of phosphorylation events
T/F: PD-1/PD-L1(2) prevents the interaction between TCR/MHC and B7/CD28
False: PD-1/PD-L1(2) prevent the signalling directly NOT the interaction
T/F: CTLA4 causes indirect regulation through failing to aid in stimulation by out competing CD28
True
How does anti-PD-1 allow for destruction of T cells
Anti-PD1 binds PD-1, inhibiting it, causing the signals from TCR/MHC and B7/CD28 to properly propagte causing destruction of the cell
