Natural killer cell receptors.

In the past year, significant strides have been made in understanding natural killing, the process whereby natural killer cells lyse target cells. Recognition of susceptible targets and activation now appear to be mediated by a natural killer cell receptor that binds carbohydrate determinants on target cells and initiates target lysis. Conversely, receptors have been identified that bind MHC class I molecules on targets that inhibit natural killer cell activation. These findings provide the basis for understanding the molecular processes in the initial steps of natural killing.