Impaired induction of CXCL9, CXCL10, IRF8, and surface HLA-DR expression in response to IFN-γ in the patients’ cells. (A) Quantitative reverse transcription-polymerase chain reaction was used to assess the induction of the CXCL9, CXCL10, and IRF8 mRNA after stimulation with IFN-γ (10³ IU/mL for 2 and 8 hours) in EBV-B cells from healthy controls (n = 3), patient P1 with the S124F mutation (RP-R2, S124F/S124F), patients P2 and P3 with the G141R mutation (RP-R2,G141R/G141R), and a patient with recessive complete IFN-γR2 deficiency (RC-R2, 218delAA/218delAA). The values shown are mean values ± standard deviation, calculated from 2 independent experiments. (B) SV40 fibroblasts from a healthy control (WT/WT), a patient with recessive partial IFN-γR2 deficiency (RP-R2, R114C/R114C), patients P1 (RP-R2, S124F/S124F) and P3 (RP-R2, G141R/G141R), 3 patients with recessive complete IFN-γR2 deficiency (RC-R2, 278delAG/278delAG; RC-R2, 382-387dup/382-387dup; and RC-R2-T168N/T168N), and a patient with dominant partial IFN-γR1 deficiency (DP-R1, 818del4/WT) were stimulated with the indicated doses of IFN-γ for 48 hours. HLA-DR induction was determined by flow cytometry. NS, no stimulation. These results are reproducible and representative of 2 independent experiments.