NK cells are large granular lymphocytes capable of killing certain tumor cells and virally infected cells in a non-MHC-restricted manner. NK cells can also effect an antibody dependent cytotoxicity that is triggered by CD16, an FcR for IgG. In NK cells, CD16 is expressed in association with ζ, a signal transducing subunit of the TCR complex. Here we show that, just as T cell activation via the TCR complex results in tyrosine phosphorylation of ζ TCR, NK cell activation via CD16 results in tyrosine phosphorylation of ζ NK. Whereas antibody-dependent cytotoxicity also results in tyrosine phosphorylation of ζ, natural cytotoxicity does not. Our results indicate that ζ functions as a transducing element for antibody dependent, but not antibody independent killing by NK cells. Consequently, NK cells are likely to express at least two distinct receptor complexes capable of triggering cytolytic effector function.
|Original language||English (US)|
|Number of pages||5|
|Journal||Journal of Immunology|
|State||Published - Jan 1 1991|
ASJC Scopus subject areas
- Immunology and Allergy