0 10 Activation Activation NNP 11 13 of of IN 14 19 human human JJ 20 23 CD4 cd4 NN 24 25 T t NN 26 37 lymphocytes lymphocyte NNS 37 38 . . . 39 50 Interaction interaction NN 51 53 of of IN 54 65 fibronectin fibronectin NN 66 70 with with IN 71 76 VLA-5 VLA-5 NNP 77 85 receptor receptor NN 86 88 on on IN 89 92 CD4 cd4 NN 93 98 cells cell NNS 99 106 induces induce VBZ 107 110 the the DT 111 115 AP-1 ap-1 NN 116 129 transcription transcription NN 130 136 factor factor NN 136 137 . . . 139 150 Fibronectin Fibronectin NNP 151 161 synergized synergize VBD 162 166 with with IN 167 175 anti-CD3 anti-cd3 JJ 176 184 antibody antibody NN 185 187 to to TO 188 195 promote promote VB 196 199 CD4 cd4 NN 200 204 cell cell NN 205 218 proliferation proliferation NN 219 221 in in IN 222 223 a a DT 224 234 serum-free serum-free JJ 235 242 culture culture NN 243 249 system system NN 250 257 whereas whereas IN 258 260 no no DT 261 274 proliferation proliferation NN 275 278 was be VBD 279 287 observed observe VBN 288 292 when when WRB 293 296 CD4 cd4 NN 297 302 cells cell NNS 303 307 were be VBD 308 316 cultured culture VBN 317 321 with with IN 322 330 anti-CD3 anti-cd3 NN 331 336 alone alone RB 337 339 or or CC 340 351 fibronectin fibronectin NN 352 357 alone alone RB 357 358 . . . 359 361 In in IN 362 370 addition addition NN 370 371 , , , 372 381 anti-CD29 anti-cd29 NN 382 383 ( ( ( 383 391 integrin integrin NN 392 396 beta beta SYM 397 398 1 1 CD 398 399 ) ) ) 400 402 as as RB 403 407 well well RB 408 410 as as IN 411 421 anti-VLA-5 anti-vla-5 NN 422 423 ( ( ( 423 428 human human JJ 429 440 fibronectin fibronectin NN 441 449 receptor receptor NN 449 450 ) ) ) 451 461 antibodies antibody NNS 462 469 blocked block VBD 470 474 this this DT 475 478 CD4 cd4 NN 479 483 cell cell NN 484 494 activation activation NN 495 497 in in IN 498 502 this this DT 503 509 system system NN 509 510 . . . 511 519 Although although IN 520 528 anti-CD3 anti-cd3 NN 529 534 alone alone RB 535 537 or or CC 538 549 fibronectin fibronectin NN 550 555 alone alone RB 556 562 cannot cannot MD 563 569 induce induce VB 570 574 IL-2 il-2 NN 575 582 message message NN 583 585 by by IN 586 589 CD4 cd4 NN 590 595 cells cell NNS 595 596 , , , 597 600 the the DT 601 612 combination combination NN 613 615 of of IN 616 624 anti-CD3 anti-cd3 NN 625 629 plus plus CC 630 641 fibronectin fibronectin NN 642 649 induced induce VBD 650 654 IL-2 il-2 NN 655 662 message message NN 663 665 by by IN 666 669 CD4 cd4 NN 670 675 cells cell NNS 675 676 . . . 677 679 In in IN 680 682 an an DT 683 691 analysis analysis NN 692 694 of of IN 695 698 the the DT 699 708 molecular molecular JJ 709 718 mechanism mechanism NN 719 721 by by IN 722 727 which which WDT 728 732 IL-2 il-2 NN 733 740 message message NN 741 744 was be VBD 745 754 generated generate VBN 754 755 , , , 756 758 we we PRP 759 765 showed show VBD 766 770 that that IN 771 772 a a DT 773 790 fibronectin-VLA-5 fibronectin-vla-5 NN 791 802 fibronectin fibronectin NN 803 811 receptor receptor NN 812 823 interaction interaction NN 824 827 may may MD 828 838 contribute contribute VB 839 841 an an DT 842 853 independent independent JJ 854 860 signal signal NN 861 869 distinct distinct JJ 870 874 from from IN 875 878 the the DT 879 882 CD3 cd3 NN 883 890 pathway pathway NN 891 893 of of IN 894 904 activation activation NN 905 907 by by IN 908 911 the the DT 912 921 induction induction NN 922 924 of of IN 925 927 an an DT 928 932 AP-1 ap-1 NN 933 948 transcriptional transcriptional JJ 949 955 factor factor NN 955 956 . . . 957 961 Thus thus RB 962 965 the the DT 966 971 VLA-5 vla-5 NN 972 983 fibronectin fibronectin NN 984 992 receptor receptor NN 993 995 on on IN 996 999 CD4 cd4 NN 1000 1005 cells cell NNS 1006 1009 can can MD 1010 1014 play play VB 1015 1016 a a DT 1017 1030 complementary complementary JJ 1031 1035 role role NN 1036 1038 in in IN 1039 1055 CD3-TCR-mediated cd3-tcr-mediated JJ 1056 1062 signal signal NN 1063 1075 transduction transduction NN 1076 1083 through through IN 1084 1087 its its PRP$ 1088 1099 interaction interaction NN 1100 1104 with with IN 1105 1116 fibronectin fibronectin NN 1116 1117 . . .