CMRF-35 mAb cross-regulates IFN-α and TNF-α production by pDCs. (A) pDCs are cultured with or without IFN-α neutralizing antibody for 30 minutes, then cells were stimulated with CpG or IFN-α for 24 and 48 hours. TNF-α secretion level was analyzed in the supernatant of cultured pDCs. Data are representative of 3 experiments. (B) pDCs were cross-linked with CMRF-35 antibody for 30 minutes and cultured with or without IFN-α neutralizing antibody for another 30 minutes, then CpG or control ODN was added to the culture. Non–cross-linked pDCs were used as control. TNF-α secretion level was analyzed in the supernatant of cultured pDCs at 48 hours. Data are representative of 3 experiments. (C) pDCs were cultured with or without TNF-α and CpG after cross-linking with CMRF-35 antibody for 48 hours; IFN-α mRNA was measured by real-time PCR. Data are representative of 3 experiments. (D) IFN-α secretion level from pDCs cultured with or without TNF-α and CpG after cross-linking with CMRF-35 antibody for 48 hours was measured by ELISA. Non–cross-linked pDCs were used as control. Data are representative of 3 experiments. Error bars represent SEM.