FIG. 1.

Restriction of lentiviral entry by feline TRIMCyp and its reversal by CypA antagonists. CrFK (ID10) cells were stably transduced with a retroviral vector bearing feline TRIMCyp (square) or vector only (circle). The cells were challenged with serial dilutions of HIV(VSV) (A, C, and E) or FIV(VSV) (B, D, and F) pseudotypes bearing a green fluorescent protein (GFP) marker gene. Seventy-two hours postinfection, GFP expression was quantified by flow cytometry. Infections were performed in the presence (filled symbols) or absence (open symbols) of medium supplemented with 2.5 μM CypA antagonists Cs (A and B), NIM811 (C and D), or Debio-025 (E and F) or their respective solvents dimethyl sulfoxide (DMSO) (Cs and NIM811) or ethanol (Debio-025). (G, H, and I) Sensitivity of HIV and FIV to Cs (G), NIM811 (H), and Debio-025 (I). TRIMCyp-expressing cells were incubated with inhibitor at 0, 0.5, 1.0, 1.5, or 2.0 μM prior to infection with HIV(VSV) or FIV(VSV) pseudotypes. Each point represents the mean of triplicate estimations.