HLA-C and neoplasm: Several recent studies reported that trogocytosis of MHC class I (MHCI) and MHC class II (MHCII) occurs not only between T cells and APCs, but between a wide variety of cell types including APCs–APCs, APCs–natural killer (NK) cells, tumor cells–T or NK cells, etc. (10–14), suggesting that the type of cell receiving such MHC may impact antigen-specific T cell activation.