NK (natural Killers) cell vaccine therapy is showing promising results in cancer treatment.

How do NK cells recognize tumor cells?

1. Inhibitory NK cell receptors interact with MHC I molecules, which are expressed by almost all normal cells in the body. Binding of inhibitory receptors to MHC I prevents NK cell activation

2.Tumor cells often downregulate MHC I expression to overcome the immune response from T lymphocytes. But NK cells are able to detect the absence or change in the level of MHC I expression

3.Cellular stress and DNA damage during tumor transformation or viral infection lead to increased expression of stress ligands, which can be detected by activating NK cell receptors.