Activation of peripheral blood pDCs with aPLs. pDCs were incubated with HL5B, HL7G, RR7F, or irrelevant IgG. (A) Time course (left) and dose response curve after 1 hour (right) are shown. Relative expression of TLR7 mRNA was determined by quantitative RT-PCR normalized to β-actin. Values represent mean ± SD of at least 5 independent experiments. *P < .02 and **P < .001 for aPLs versus IgG. (B) Relative expression of IFNα (left) and TNFα (right) mRNA normalized to β-actin. Values represent mean ± SD of at least 5 independent experiments. *P < .01, **P < .001 for HL5B versus IgG. (C) Effect of inhibition of IFNα by BDCA-2 (1 μg/mL; left) or inhibition of TNFα by adalimumab (0.1 μg/mL; right) on TLR7 expression. *P < .03 for HL5B versus HL5B plus inhibitor. (D) Effect of inhibition of NFκB by Ro106-9920 (5μM). Expression of TLR7 (left) and IFNα (right, solid line) or TNFα (right, dotted line). *P < .03, **P < .001 for HL5B versus HL5B plus inhibitor.