Fig. 1.

Enhancement of expression of CD40L on immobilized anti-CD3-activated CD4⁺ T cells by IL-12. CD4⁺ T cells (2 × 10⁵/well) were cultured in wells with immobilized anti-CD3 (64.1, 100 ng/well) in the presence or absence of a metalloproteinase inhibitor KB8301 (10 μm) with or without IL-12 (10 ng/ml). After 96 h of incubation, the cells were harvested and stained with FITC-conjugated anti-CD40L MoAb or control MoAb and PE-conjugated anti-CD4 MoAb. Immunofluorescent staining, fixation, and analysis were performed as described in Materials and Methods. Mean fluorescence intensity (MFI) for staining with FITC-conjugated MoAb is indicated. The data are representative of three different experiments.