Fig. 3. Expression of MxB is not necessary for the ability of SAMHD1 to restrict SIV_mac.

(A) Restriction of SIV_mac in THP-1-MxB-KO cells. THP-1 and THP-1-MxB-KO cell lines were challenged with increasing amounts of SIV_mac or SIV_macΔVPX expressing GFP as a reporter of infection. Infection is shown as the percentage of GFP-positive cells 72 h post-challenge as measured by flow cytometry. Experiments were performed in triplicate and a representative experiment is shown. 500 μL of SIV_mac or SIV_macΔVPX represents a MOI of 2. (B) Restriction of SIV_mac in THP-1-SAMHD1-KO cells. THP-1 and THP-1-SAMHD1-KO cell lines were challenged with increasing amounts of SIV_mac or SIV_macΔVPX. Infection is shown as the percentage of GFP-positive cells 72 h post-challenge as measured by flow cytometry. Experiments were performed in triplicate and a representative experiment is shown. 500 μL of SIV_mac or SIV_macΔVPX represents a MOI of 2. (C) Restriction of SIV_mac in THP-1-MxB/SAMHD1-KO cells. THP-1 and THP-1-MxB/SAMHD1-KO cell lines were challenged with increasing amounts of SIV_mac or SIV_macΔVPX. Infection is shown as the percentage of GFP-positive cells 72 h post-challenge as measured by flow cytometry. 500 μL of SIV_mac or SIV_macΔVPX represents a MOI of 2. (D) Relative infection of SIVmac and SIV_macΔVPX in all cells. The results of three independent experiments with standard deviation are shown, * denotes P value of < 0.05, ** denotes P value of < 0.0001, ns denotes not significant as determined by One-Way ANOVA Tukey’s multiple comparisons test. Black bars represent SIV_mac infection. Grey bars represent SIV_macΔVPX infection.