Open AccessIL‐2 signalling in T and natural killer (NK) cells associated with their class I‐non‐restricted killing activity
Author(s) -
YONEDA K.,
OSAKI T.,
YAMAMOTO T.
Publication year - 1996
Publication title -
clinical & experimental immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.329
H-Index - 135
eISSN - 1365-2249
pISSN - 0009-9104
DOI - 10.1046/j.1365-2249.1996.d01-801.x
Subject(s) - tyrosine phosphorylation , cytotoxic t cell , phosphorylation , interleukin 12 , biology , interleukin 21 , microbiology and biotechnology , tyrosine , natural killer cell , biochemistry , in vitro
The signal transduction of IL‐2 in NK cells and T cells was compared. On 5 min incubation of these cells with IL‐2, we observed tyrosine phosphorylation of 105‐kD and 110‐kD proteins in NK cells and of 95‐kD and 110‐kD proteins in T cells. The phosphorylation reached maximal levels in 15 min in both NK and T cells, but the levels were higher in NK cells, which showed superior killing against Daudi cells. With this phosphorylation, p52 shc was also tyrosine‐phosphorylated and p21 ras was activated by the short term (10 min) treatment of NK and T cells with IL‐2. These signals were completely suppressed by anti‐IL‐2Rβ MoAb, but only slightly suppressed by anti‐IL‐2Rα MoAb, correlated with the suppression of the class‐I‐non‐restricted cytotoxic activity of NK and T cells by these MoAbs. When tyrosine phosphorylation was inhibited by herbimycin A and genistein, the cytotoxic activities of NK and T cells were nearly completely suppressed. In addition, the tyrosine phosphorylation of JAK3 by IL‐2 was more prominent in NK cells than in T cells, but JAK1, JAK2, STAT1α, STAT2 and STAT3 were not phosphorylated. These results indicate that the IL‐2 signal flows downstream via both ras‐dependent and ras‐independent pathways and that the superior killing activity of NK cells depends on their high susceptibility to protein tyrosine phosphorylation by IL‐2.