Fig 3.

Zn²⁺ was essential for PDTC's antiviral activity. (A, B) HEC-1-A cells cultured in complete medium were exposed to PDTC (25 μg/ml) in the presence of serial concentrations of EDTA (A) or 10 μM EDTA-Ca, -Mg, -Zn, or -Cu (B) and infected with HSV-2 (MOI = 1). (C) HEC-1-A cells were cultured in FBS-free medium containing 0.5 μM Zn²⁺ or serial concentrations of Cu²⁺ and PDTC (25 μg/ml) prior to HSV-2 infection (MOI = 1). (D) HEC-1-A cells were exposed to PDTC (25 μg/ml) in the presence of serial concentrations of TPEN and then infected with HSV-2. Each TPEN concentration was in duplicate. Mock-treated cells were exposed to HSV-2 alone. The gD expression levels were determined 24 h p.i. Error bars show standard deviations.