Nuclear extracts of the CTCL cell lines HUT78, MyLa, and SeAx contain AP-1–oligo binding activities, which include JunD. (A) Tests with antibodies against JunD (lanes 3, 7, and 11), c-Jun (lanes 4, 8, and 12), and c-Fos (lanes 5, 9, and 13). Lane 1, peripheral blood lymphocytes (negative control); lanes 2, 6, and 10, incubations without antibodies. Lanes 2 through 5, nuclear extracts from HUT78 cells; lanes 6 through 9, nuclear extracts from MyLa cells; lanes 10 to 13, nuclear extracts from SeAx cells. (B) AP-1–oligo binding activities in the nuclear extracts of malignant cells of eight SS patients (lanes 3 through 10). Lane 1, peripheral blood lymphocytes (negative control); lane 2, nuclear extract from HUT78 cells (positive control). (C) The AP-1–oligo-binding activities of patient 2 (lanes 4 through 7) and 3 (lanes 8 through 11) contain JunD. Lane 1, peripheral blood lymphocytes (negative control); lane 2, nuclear extracts of HUT78 cells with (lane 3) and without (lane 2) JunD antibody (positive control); lanes 4 and 8, incubations without antibodies; lanes 5 and 9, nuclear extracts with c-Fos antibody; lanes 6 and 10, nuclear extracts with c-Jun antibody; lanes 7 and 11, nuclear extracts with JunD antibody. C1, JunD-DNA complex; JunD/Ab, JunD-DNA-antibody complex. The complex above C1 migrating at nearly the same position as JunD/Ab is probably unspecific, as it reacts with no antibody and is not seen in every experiment.