Fc gamma Receptor III and Fc gamma Receptor IV on Macrophages Drive Autoimmune Valvular Carditis in Mice

Tumourgenetics and immunogenetic

Ly49A inhibitory receptors redistribute on natural killer cells during target cell interaction

When T effector cells meet antigen-bearing target cells, there is a specific accumulation of T-cell receptors, co-receptors and structural proteins at the point of cell–cell contact. Ly49 inhibitory receptors bind to murine major histocompatibility complex (MHC) class I molecules and prevent natural killer-(NK) cell cytotoxicity. In this study we have tested whether inhibitory receptors accumulate at the point of cell–cell contact when NK cells encounter target cells bearing MHC class I ligands for those inhibitory receptors. We have used RNK-16 effector cells that express Ly49A receptors and have found that there was a specific accumulation of Ly49A receptors at the point of NK cell–target cell contact when the target cells expressed H-2Dd. We also observed that engagement of Ly49A on NK cells resulted in an altered redistribution of potential triggering receptors CD2 and NKR-P1. These data indicate that inhibitory receptors, like activating receptors, may specifically aggregate at the point of cell–cell contact which may be necessary for them to mediate their full inhibitory effect