Fig. 2

Release of infectious HIV-1Δvpu and HIV-1 in the presence of SARS-CoV- 2 E protein. HEK293 cells were co-transfected with either the empty pcDNA3.1( +) vector or vectors expressing the HSV-1 gD[ΔTMCT], HSV-1 gD, or SARS-CoV-2 E protein and pNL4-3. At 48 h, the culture supernatants were collected and subjected to low-speed centrifugation to remove cellular debris, and levels of infectious virus released into the culture supernatants were determined using TZM-bl cell assays. A The level of HIV-1 infectivity in the culture medium from cells co-transfected with either the empty pcDNA3.1( +) vector or vectors expressing gD[ΔTMCT], gD, or SARS-CoV-2 E protein and pNL4-3. B Expression of the gD proteins or E protein from restriction assays in (A). Expression of the E protein or gD proteins from restriction assays in (B) was normalized with β-actin using an anti-β-actin antibody and immunoblots. C HEK293 cells were co-transfected with either the empty pcDNA3.1( +) vector or vectors expressing 1) Vpu/BST-2/∆vpuHIV-1; 2) pcDNA3.1( +)/BST-2/∆vpuHIV-1; 3) SARS-CoV- 2 E/BST-2//∆vpuHIV-1; 4) SARS-CoV-2 E/∆vpuHIV-1; 5) gD/pcDNA3.1( +)/∆vpuHIV-1; or 6) gD[TMCT]/pcDNA3.1( +)/∆vpuHIV-1. At 48 h, culture supernatants were collected as described above and assayed for infectious HIV-1. The numbers above the figure correspond to the lanes in Panel D. D The cells collected from the experiments were lysed. Lysates were normalized for β-actin and analyzed for Vpu or E proteins using an anti-HA antibody (upper panel); BST-2 using an anti-BST-2 antibody (middle panel); gD proteins using an anti-gD monoclonal antibody (lower panel). The blot for β-actin is shown at the bottom. All restriction assays in Panels A and C were performed at least four times and statistical differences from the pcDNA3.1( +)/HIV-1 control was evaluated using a two-tailed Students t-test, with p < 0.01 () considered significant