Fig S1.

Similar WT and TM1 surface expression among multiple strains of Env expressed by recombinant VACV. In the same experiments shown in Fig. 3, HEK 293T cells were infected (MOI = 3) recombinant VACV and stained for VACV A33 to gate on infected cells and for Env using (A) 2G12, an anti-gp120 mAb, or (B) 2F5, an anti-gp41 mAb under non-permeabilizing conditions (n = 3 independent experiments). The un-normalized mean fluorescence intensity (MFI) of the Env stains is shown. Statistical analysis is described in Fig. 3.