Defects in NF-κB and AP-1 activity in viperin^−/− CD4⁺ T cells. (A,B) EMSA analysis of NF-κB (A) and AP-1 (B) activity in nuclear extracts from unstimulated or stimulated CD4⁺ T cells for 72 hours. The supershift assays were performed with indicated antibodies. Lane 1 was probe-only control without lysates. Lanes 8 and 9: mutant probes (mut) were used to replace specific probes in binding reactions to verify the specificity of probes. (C) Immunoblotting analysis for NF-κB subunits in CD4⁺ T cells stimulated with anti-CD3/CD28 for 72 hours. Results are representative of 3 independent experiments.