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For TF silencing, hVSMCs were transfected with siCtrl or siRELA, siEGFR, siSP1, or siFOS (25 nM) (Dharmacon); 72 hours later, senescence was induced with Doxo for an additional 72 hours. For DPP4 silencing, hVSMCs were transfected with siCtrl or siDPP4 (25 nM). For siRNA screening, a custom siRNA library plate was designed including siRNA pools to silence CFD, C9, CFB, C4A, C7, FGB, FGG, FX, FV, FII, SERPINE1, TIMP1, MMP1, and PLAT. This included a nontargeting control siRNA. Sequences and catalog numbers for siRNA custom screening are available in Supplemental Table 1. All small RNA transfections were performed using Lipofectamine RNAiMAX (Thermo Fisher Scientific).

Pre-designed pooled siRNAs targeting IFITM1 (si-IFITM1), IFITM2 (si-IFITM2), and IFITM3 (si-IFITM3), as well as negative control scramble siRNA (si-Ctrl) were purchased from Dharmacon (Lafayett, CO, USA). Cells were transfected with different siRNAs using Lipofectamine 2000 reagent (Thermo Fisher Scientific).

The epithelial cells were plated on 6 cm dishes to obtain 30–40% confluency at the day of transfection. The subconfluent cells were transfected with siRNAs by using the Oligofectamine reagent (Invitrogen) by following the manufacturer’s instructions. Gene silencing was performed by the transfecting of siRNA duplexes from 50 nM of validated siRNAs against human TRIM25 (ID#15204, “siTRIM25#1”) from ThermoFisher Scientific or, alternatively, a mixture of FlexiTube siRNAs for human TRIM25 (SI0000072170, SI0000072163, SI0000072156 and SI0000072149, “siTRIM25#2”) from Qiagen (Hilden, Germany). Alternatively, the cells were transfected with the same amounts of FlexiTube siRNA duplexes for hnRNPH (“sihnRNPH#1”) from Dharmacon (St. Leon-Rot, Germany) or from Santa Cruz (“sihnRNP#2”). A non-targeting control siRNA (siCtrl, #D001206-13) was from Dharmacon. The specific silencing of the targeted genes was validated by Western blot analysis.

HPLC-purified siRNA and DsiRNA RNAi with indicated (UU) overhangs were obtained from GE Dharmacon: (1) siCTRL sense: 5′-CGU UAA UCG CGU AUA AUA C(UU)-3′, antisense: 5′-GUA UUA UAC GCG AUU AAC G(UU)-3′; (2) DsiCTRL sense: 5′-CGU UAA UCG GCU AUA AUA CGC GUA U-3′, antisense: 5′-AUA CGC GUA UUA UAC GCG AUU AAC G(UU)-3′; (3) siSTAT3 sense: 5′-GGU CAA AUU UCC UGA GUU G(UU)-3′, antisense: 5′-CAA CUC AGG AAA UUU GAC C(UU)-3′; (4) DsiSTAT3 sense: 5′-GGU CAA AUU UCC UGA GUU GAA UUA U-3′, antisense: 5′-AUA AUU CAA CUC AGG AAA UUU GAC C(UU)-3′; (5)Chol-siCTRL: siCTRL with 3′-cholesterol conjugated to the sense strand; (6)Chol-siSTAT3: siSTAT3 with 3′-cholesterol conjugated to the sense strand; (7) Chol-DsiCTRL: DsiSTAT3 with 3′-cholesterol conjugated to the sense strand; (8) Chol-DsiSTAT3: DsiSTAT3 with 3′-cholesterol conjugated to the sense strand. For in vitro studies, lyophilized RNAi molecules were resuspended in sterile, nuclease-free ddH₂0 [100 μM] as directed (GE Dharmacon) and stored in aliquots [10 μL] at −80°C. For in vivo studies, lyophilized RNAi molecules were resuspended in the indicated buffer on the day of injection.