Primer sequences

Cells or supernatants were resuspended in 1 mL of TriZol reagent (Life Technologies, Bleiswijk, The Netherlands). Total RNAs were isolated according to manufacturer’s instructions. RNA yield and purity were determined using a spectrophotometer NanoDrop 1000 (Thermo Scientific, Bleiswijk, The Netherlands). Total RNAs were reverse transcribed using the Super Script III Reverse Transcriptase kit according to manufacturer’s instructions (Invitrogen, Merelbeke, Belgium). cDNA samples were used to amplify SARS-CoV-2 gene E with Takyon TaqMan kit [33 (link)] and human genes of interest with Takyon SYBR Green kit (Eurogentec, Liège, Belgium) in a Light Cycler 96 device (Roche Diagnostics, Mannheim, Germany). Primer sequences (Eurogentec, Liège, Belgium) are listed in Table 1. The relative gene expression was calculated using the ΔCq method with human hprt as housekeeping gene.

Total RNA was extracted from the different cell lines using the Nucleospin RNA II kit (Macherey-Nagel, Düren, Germany). The amount of extracted RNA was quantified using a DeNovix DS-11 spectrophotometer (DeNovix Inc., Wilmington, DE, USA) and the purity of the RNA was checked by the ratio of absorbance at 260 nm vs. 280 nm. Total RNA was subjected to reverse transcription using the Maxima First Strand cDNA Synthesis Kit (ThermoFisher Scientific, France) according to the protocol provided by the manufacturer. PCR reactions were performed using 2X SYBR^® Green Universal QPCR Master Mix (ThermoFisher Scientific). Primer sequences (Eurogentec, Seraing, Belgium) used for the PCR reactions are given in Table 1. HPRT gene was used to normalize the expression of transcripts of interest. PCR reactions were performed using the Mx3005p Quantitative System (Stratagene) as previously described [16 (link)]. PCR conditions were as follows: 95°C for 30 s, Tm °C for 60 s, 72°C for 20 s (40 cycles). The analysis of amplification was performed using the Mx3005p software and relative quantification was performed using the method described by Pfaffl that takes in account the efficiency of each sequence amplification [24 (link)]. Student’s t-test was used for statistical analysis. A p-value < 0.05 was considered statistically significant.