Fig. 7. IL-1 activity in cis and in trans is required for bead induction of CL-1 expression. Micrographs of immunofluorescence staining for CL-1 expression (green) after 24 hours of anti-5 mAb-coated beads (red) addition in the absence (A, B and D) or presence of 10 µg/ml anti IL-1 (C). Arrows point to cells expressing CL-1, but with no beads. Bar, 50 µm.