(A) Scheme of shuttle plasmids for generation of recombinant VV. SIRPαor SIRPα-Fc expression is controlled by the late F17R promoter, and yellow fluorescent protein (YFP) expression by the early/late Pse/I promoter. (B-C) OV10, OV10–315, MC38, LM7, or F420 were infected at a MOI of 0.1 with YFP-VV, SIRPα-VV, or SIRPα-Fc-VV. 24–48 hours post-infection expression of (B) CD47 or (C) Fc was determined by FACS analysis (n=3; mean percent expression +/−SD; ANOVA; *p<0.05, **p<0.01; ****p<0.0001).