Macaque interferon-induced transmembrane proteins limit replication of SHIV strains in an Envelope-dependent manner
Fig 5
Knockout of macaque IFITMs affects IFNα sensitivity of unadapted SHIV.
(A) Western blot analysis of Ptm IFITM-knockout cell pools using anti-IFITM3/3A (left panel) and anti-IFITM1 (right panel) antibodies. CRISPR/Cas9 ribonucleoproteins (crRNPs) that targeted IFITM1 and IFITM3 (indicated “M1+M3”), IFITM3A, IFITM3, or a non-targeting control (indicated “NTC”) is indicated at the top. IFNα-treatment (1000 U/ml) of cells is indicated above each lane. The numbers below the bottom panel indicate the IFITM3/3A:GAPDH (left panel) or IFITM1:GAPDH (right panel) signal relative to IFNα-treated, NTC. (B–C) Effect of IFNα-treatment on replication of SHIV-Q23AE (B) and SHIV-AD8-EO (C) in Ptm IFITM-knockout cell pools over a 9-day time course. The identity of each SHIV is indicated above the chart. Color-coding indicates whether the SHIVs are adapted (orange) or unadapted (blue). The key at the right of the graph indicates the color corresponding to each knockout cell line. Replication in the presence of IFNα (1000 U/ml) is indicated in the dashed lines, whereas control replication in the absence of IFNα is indicated in the solid lines. Data points represent the average of four independent experiments, and error bars represent SD. (D–E) Area under the curve (AUC) ratio for (D) SHIV-Q23AE and (E) SHIV-AD8-EO determined from the replication curves shown in (B) and (C), respectively. Data represent the average of four independent experiments, and error bars represent SEM. AUC values were compared using one-way analysis of variance (ANOVA) followed by Dunnett's multiple comparisons test. ** p = 0.0054, * p = 0.0156.