NATURAL-KILLER-CELL RECEPTORS

The specificity in the recognition of hematopoietic target cells by na tural killer cells is primarily provided by inhibitory receptors and s everal such receptors have been identified in the past year. Surprisin gly, the recognition of MHC class I molecules by inhibitory receptors on human natural killer cells involves two different types of receptor s, one with Ig domains (killer cell inhibitory receptor), and another with C-type lectin domains (CD94-NKG2). Mouse natural killer cells rec ognize MHC class I molecules through the C-type lectin Ly49 receptors but also express a receptor, of unknown ligand specificity, that is re lated to the killer cell inhibitory receptor.