Preferential involvement of Go and Gz proteins in mediating rat natural killer cell lysis of allogeneic and tumor target cells.

摘要: IL-2-activated NK cells from PVG rats potently lyse target expressing allo-MHC class I determinants. Here, we investigated the role that G proteins play in mediating this activity. Pretreatment of with pertussis toxin (PT) or cholera (CT) inhibited cell killing tumor (YAC-1 P815), and allogeneic cells. ADP ribosylation assay revealed PT ribosylates a 39-kDa protein, whereas CT 45 to 47-kDa protein membranes. Membranes prepared intoxicated either lost their ability incorporate [32P]NAD. These membranes possess Gi, Go, Gs, Gz as demonstrated by immunoblot analysis. However, Gq was not clearly detected method. were permeabilized streptolysin O. Permeabilized incorporated Abs Gz, determined flow cytometric When Go but Gq, inside cells, significant reduction lysis observed, suggesting important roles transducing signals necessary Our results show for first time allo-MHC-encoded provide evidence involvement recognition The effect is novel has been previously described any other system type.