0 7 Cutting cutting JJ 8 12 edge edge NN 12 13 : : : 14 17 TCR TCR NNP 18 29 stimulation stimulation NN 30 32 by by IN 33 41 antibody antibody NN 42 45 and and CC 46 55 bacterial bacterial JJ 56 68 superantigen superantigen NN 69 76 induces induce VBZ 77 82 Stat3 stat3 NN 83 93 activation activation NN 94 96 in in IN 97 102 human human JJ 103 104 T t NN 105 110 cells cell NNS 110 111 . . . 113 119 Recent recent JJ 120 124 data datum NNS 125 129 show show VBP 130 134 that that IN 135 142 TCR/CD3 tcr/cd3 JJ 143 154 stimulation stimulation NN 155 162 induces induce VBZ 163 173 activation activation NN 174 176 of of IN 177 182 Stat5 stat5 NN 183 185 in in IN 186 192 murine murine JJ 193 194 T t NN 195 200 cells cell NNS 200 201 . . . 202 206 Here here RB 206 207 , , , 208 210 we we PRP 211 215 show show VBP 216 220 that that IN 221 224 CD3 cd3 NN 225 233 ligation ligation NN 234 236 by by IN 237 240 mAb mab NN 241 244 and and CC 245 259 Staphylococcal staphylococcal JJ 260 271 enterotoxin enterotoxin NN 272 273 ( ( ( 273 275 SE SE NNP 275 276 ) ) ) 277 283 induce induce VBP 284 285 a a DT 286 291 rapid rapid JJ 291 292 , , , 293 302 gradually gradually RB 303 315 accumulating accumulate VBG 315 316 , , , 317 329 long-lasting long-lasting JJ 330 338 tyrosine tyrosine NN 338 339 , , , 340 343 and and CC 344 350 serine serine NN 351 366 phosphorylation phosphorylation NN 367 369 of of IN 370 375 Stat3 Stat3 NNP 376 377 ( ( ( 377 380 but but CC 381 384 not not RB 385 390 Stat5 Stat5 NNP 390 391 ) ) ) 392 394 in in IN 395 411 allogen-specific allogen-specific JJ 412 417 human human JJ 418 422 CD4+ cd4+ JJ 423 424 T t NN 425 429 cell cell NN 430 435 lines line NNS 435 436 . . . 437 439 In in IN 440 448 contrast contrast NN 448 449 , , , 450 454 IL-2 il-2 NN 455 462 induces induce VBZ 463 464 a a DT 465 470 rapid rapid JJ 471 474 and and CC 475 484 transient transient JJ 485 493 tyrosine tyrosine NN 494 497 and and CC 498 504 serine serine NN 505 520 phosphorylation phosphorylation NN 521 523 of of IN 524 529 Stat3 Stat3 NNP 529 530 . . . 531 539 Compared compare VBN 540 544 with with IN 545 549 IL-2 il-2 NN 549 550 , , , 551 554 CD3 cd3 NN 555 563 ligation ligation NN 564 571 induces induce VBZ 572 573 a a DT 574 581 delayed delay VBN 582 587 Stat3 stat3 NN 588 595 binding bind VBG 596 598 to to TO 599 614 oligonucleotide oligonucleotide NN 615 621 probes probe NNS 622 626 from from IN 627 630 the the DT 631 637 ICAM-1 icam-1 NN 638 641 and and CC 642 647 IL-2R il-2r NN 648 653 alpha alpha NN 654 662 promoter promoter NN 662 663 . . . 664 676 CD3-mediated cd3-mediated JJ 677 687 activation activation NN 688 690 of of IN 691 696 Stat3 Stat3 NNP 697 699 is be VBZ 700 706 almost almost RB 707 717 completely completely RB 718 727 inhibited inhibit VBN 728 730 by by IN 731 732 a a DT 733 736 Src Src NNP 737 743 kinase kinase NNP 744 753 inhibitor inhibitor NN 754 755 ( ( ( 755 758 PP1 PP1 NNP 758 759 ) ) ) 759 760 , , , 761 768 whereas whereas IN 769 781 IL-2-induced il-2-induced JJ 782 787 Stat3 stat3 NN 788 798 activation activation NN 799 801 is be VBZ 802 812 unaffected unaffected JJ 812 813 . . . 814 816 In in IN 817 827 conclusion conclusion NN 827 828 , , , 829 831 we we PRP 832 836 show show VBP 837 841 that that IN 842 845 CD3 cd3 NN 846 854 ligation ligation NN 855 857 by by IN 858 861 mAb mab NN 862 865 and and CC 866 868 SE SE NNP 869 877 triggers trigger VBZ 878 879 a a DT 880 885 rapid rapid JJ 885 886 , , , 887 900 PP1-sensitive pp1-sensitive JJ 901 909 tyrosine tyrosine NN 910 913 and and CC 914 920 serine serine NN 921 936 phosphorylation phosphorylation NN 937 939 of of IN 940 945 Stat3 stat3 NN 946 948 in in IN 949 954 human human JJ 955 959 CD4+ cd4+ JJ 960 961 T t NN 962 967 cells cell NNS 967 968 . . . 969 977 Moreover moreover RB 977 978 , , , 979 981 we we PRP 982 989 provide provide VBP 990 998 evidence evidence NN 999 1003 that that IN 1004 1011 TCR/CD3 TCR/CD3 NNP 1012 1015 and and CC 1016 1020 IL-2 IL-2 NNP 1021 1027 induce induce VBP 1028 1033 Stat3 stat3 NN 1034 1044 activation activation NN 1045 1048 via via IN 1049 1057 distinct distinct JJ 1058 1067 signaling signaling NN 1068 1076 pathways pathway NNS 1076 1077 . . .