Journal: Journal of Virology

Article Title: LY6E Restricts Entry of Human Coronaviruses, Including Currently Pandemic SARS-CoV-2

doi: 10.1128/JVI.00562-20

Figure Lengend Snippet: IFITMs modulate HCoV-OC43 infection of HepG2 and C3A cells to a similar extent and via the same mechanism. HepG2 and C3A cells were stably transduced with a control retroviral vector (pQCXIP) or a retroviral vector expressing an N-terminally FLAG-tagged IFITM1-EX2 or IFITM3-EX2. The resulting cell lines were infected with HCoV-OC43 at 0.5 MOI. (A) Cells were fixed at 24 hpi and virally infected cells were visualized by IF staining of HCoV-OC43 N protein (green). Cell nuclei were visualized by DAPI staining (blue). (B) HCoV-OC43 NP and exogenously expressed N-terminally FLAG-tagged IFITM proteins and total intracellular IFITM2/3 were determined by Western blotting assays with a monoclonal antibody against the FLAG tag and a rabbit polyclonal antibody against IFITM2/3. β-actin served as a loading control. (C) Intracellular viral RNA was quantified by a qRT-PCR assay and presented as copies per 100 ng total RNA. Error bars indicate standard deviations ( n = 4). (D) Viral yields were determined with a plaque assay. Error bars indicate standard deviations ( n = 4). (E) HepG2 and C3A stably transduced with a control retroviral vector (pQCXIP) or a retroviral vector expressing IFITM1, IFITM1-EX2, or IFITM3-EX2 were infected with HCoV-OC43pp. Luciferase activities were determined at 72 hpi. Relative infection represents the luciferase activity normalized to that of HepG2 cells transduced with empty vector (pQCXIP). Error bars indicate standard deviations ( n = 6).

Article Snippet: Monoclonal antibody against human IFITM1 (catalog number 60047-1), rabbit polyclonal antibody against human IFITM3 (catalog number 11714-1-AP), which also efficiently recognizes IFITM2 and weakly cross-reacts with IFITM1, were purchased from Proteintech Group, Inc.

Techniques: Infection, Stable Transfection, Transduction, Control, Retroviral, Plasmid Preparation, Expressing, Staining, Western Blot, FLAG-tag, Quantitative RT-PCR, Plaque Assay, Luciferase, Activity Assay