Fig. 4

IFN α does not block SAMHD1 degradation in THP1 cells when VLPs-Vpx are pseudotyped with A-MLV. a Levels of Vpx incorporation in VLPs pseudotyped with different envelopes. 250 RT mU of VLPs-Vpx pseudotyped with either VSV-G (left lane) or A-MLV (center lane) were loaded on a gel and levels of Vpx were probed by Western Blot. 250 RT mU of VLPs-∆vpx pseudotyped with VSV-G (rigth lane) were used as a negative control. 50 RT mU of the same VLPs preparations were loaded and probed for p27 as a loading control. b THP1 cells were treated for 24 h with 0 (solid lines) or 1000 (dotted lines) U/mL of IFNα, then with the indicated amount of VLPs–Vpx pseudotyped with A-MLV (as determined by RT activity). Cells were treated with the indicated amounts of VLPs-Vpx and SAMHD1 degradation was measured by flow cytometry 16 h later. One representative experiment is shown. c Combined data from three independent experiments for the effect of IFNα (white bar), using a viral dose within linear range. n = 3; ns non significant (t test). d Combined data from three independent experiments for the effect of IFITM3 overexpression (white bar), using a viral dose within linear range. n = 3; ns non significant (t test)