FIG. 5.

DcR2 allows TRAIL-DISC formation but prevents its activation. (A) HeLa cell populations were stimulated with 5 μg/ml recombinant His-TRAIL for the indicated time periods. After cell lysis, DISCs were immunoprecipitated (IP) with an anti-caspase-8 (casp-8) antibody and analyzed by immunoblotting using antibodies to DR4, DR5, DcR1, DcR2, FADD, caspase-8, and caspase-10. (B) HeLa cell populations were stimulated as described above, and DISC analysis was performed using the anti-DR5 antibody or an isotype control. (C) The DcR2-expressing HeLa cell population was stimulated as described for panel A, and DISC analysis was performed using an anti-DcR2 antibody. Caspase-8 and caspase-10 cleavage products are indicated by black arrowheads.