Delayed interferon responses, IL-27 and IFN-λ responses in the cells of P1. (A) HLA-DR induction in SV-40 fibroblasts of WT/WT, P1, P696S/P696S, and −/− subjects after 48 hours of stimulation with the indicated dose of IFN-γ. HLA-DR was quantified by FACS analysis. Solid area represents no stimulation; thin solid line, 10 IU/mL IFN-γ; and thick solid line, 103 IU/mL IFN-γ. (B) VSV viral titer after VSV challenge. The SV40-fibroblasts of P1 controlled VSV replication after prior treatment of IFN-α for 18 hours. Bold line indicates without IFN-α; and dashed line, with 105 IU/mL IFN-α. (C) Cell viability after VSV challenge. The viability of SV40-fibroblasts from P1 was similar to that of healthy control cells after prior treatment with 105 IU/mL IFN-α for 18 hours. The results are representative of 2 independent experiments. (D) GAF DNA-binding activity was impaired in the EBV-B cells of P1, as shown by comparison with the cells of healthy controls after stimulation with 100 ng/mL IL-27 for 15 minutes. (E) On stimulation with 100 ng/mL IL-27, CXCL9 induction was significantly impaired in the EBV-B cells of P1 at the 1-hour and 2-hour time points, as shown by comparison with healthy controls. However, CXCL9 induction was nonetheless stronger in the cells of P1 than in P696S/P696S and −/− EBV-B cells. (F) After stimulation with 20 ng/mL IFN-λ, IFIT1 induction was normal in the EBV-B cells of P1. This level of induction was greater than that observed in P696S/P696S and −/− EBV-B cells. The results are representative of 3 independent experiments. One red asterisk indicates P < .05; and 3 red asterisks indicate P < .005.
