BST2 and infection: Quantitation of MLV-GFP infection by the aforementioned methods confirmed that the growth of foci of MLV-GFP infection was not measurably inhibited by either an agar overlay or tetherin expression (Fig. 4A and B), and unlike the results with VSV-GFP, this was also true for the total GFP intensity in a larger microscopic field (Fig. 4C).