PR3 induces expression of PAR-2 on mDCs. (A) Immature DCs were incubated with PR3 or HLE and TNF-α for 48 hours. For PAR-2 staining, cells were incubated with FITC-conjugated mouse anti–human PAR-2 or IgG_2a isotype control for 30 minutes at 4°C and then were analyzed by flow cytometry. The positive staining is expressed as mean percentage of positive cells and as a median fluorescence intensity (MFI) ratio described in “Patients, materials, and methods.” Values are the mean ± SEM (donors n = 16). (B) iDCs were stimulated with PR3 for 24 hours at 37°C. PR3 was pretreated with and without PMSF for 30 minutes at 37°C before use. Immature DCs were pretreated with and without cytochalasin B (CCB) for 30 minutes or CHX for 6 hours at 37°C. Then, the cells were stimulated with and without PR3 for 24 hours in the presence or absence of CCB or CHX. After the incubation, the cells were collected and the expression of PAR-2 on the cells was analyzed by flow cytometry. The positive staining is expressed as mean percentage of positive cells and as a median fluorescence intensity (MFI) ratio. *P < .01 compared with PR3 alone.