FTL and viral infectious disease: Notably, the protein levels of FTL (Fig. 3b) in the SUIT-2/shFTH1#3 cells were significantly altered after shFTH1 viral infection compared with those in either the SUIT-2 or the Scr cells; therefore, we specifically selected the sh#1 and sh#4 FTH1-knockdown clones for further analyses.