Effect of HCMV infection on A20 protein level. (A) HF cells were infected with HCMV or UV-inactivated virus (UV-HCMV) at the indicated MOIs. Total cell lysates were prepared at 24 h and immunoblotted with anti-A20 and anti-β-actin Abs. (B) HF cells were infected with HCMV or UV-HCMV at an MOI of 0.5 for the indicated times, followed by immunoblotting as in (A). (C) HF cells were untreated or treated with TNF-α (50 ng/ml) for 2 h. Cells were fixed with the paraformaldehyde procedure and IFA was performed with anti-A20 Ab. A mounting solution containing Hoechst dye was used to stain cell nuclei. FITC-conjugated anti-mouse IgG and rhodamine/Red X-coupled anti-rabbit IgG Abs were used for visualization. (D) HF cells were mock-infected or infected with HCMV at an MOI of 0.5 for 24 h. Cells were fixed and stained with anti-A20 and anti-IE1 Abs as in (C). For visualization, rhodamine/Red X-coupled anti-mouse IgG and FITC-conjugated anti-rabbit IgG Abs were used.