Figure 1.

Differential effector functions of NK cell subsets: NK cells have two major subsets in relation with their CD56 expression levels. High expression levels of CD56 is observed in immature NK cell subset, which does not express high levels of CD16 and best known with abundant expression of cytokines. This subset has inflammatory and/or immune regulatory properties and low cytotoxic activity. On the other hand, the subset with low expression levels of CD56 in known as mature NK cell subset, which express high levels of CD16 and is associated with clearance of tumor cells and transfected or virus-infected cells thanks to cytotoxic activity. This subset is also associated with diminished cytokine production capacity.