Evasion of immune response

Question 1

Reduced MHC expression

Answer 1

Tumour cells display low levels of MHC class I molecules on cell surface and since cytotoxic T lymphocytes recognize antigens in the context of MHC class I molecules, tumour cells go undetected

Question 1

Ways in which tumour cells avoid detection by immune system

Answer 1

1. Reduced MHC expression
2. Poor stimulatory molecules

Question 2

Poor co-stimulatory molecules

Answer 2

T-cells require both expression of MHC and costimulatory molecules to be activated and tumour cells lack these co-stimulatory molecules and so T-cells will only be partially activated