4.5 g l glucose

Vero cells (ATCC CCL-81, Manassas, Virginia, United States) and Vero/hSLAM cells (ECACC 04091501, Porton Down, United Kingdom) were grown in Dulbecco’s Modified Eagle Medium (DMEM) with 4.5 g/L glucose (Microtech, Naples, Italy) supplemented with antibiotic solution 100× (Himedia, Naples, Italy) and 10% Fetal Bovine Serum (Microtech).
HSV-1 (strain SC16), containing a lacZ gene driven by the cytomegalovirus IE-1 promoter to express beta-galactosidase, and fluorescent HSV-1, containing the GFP reporter inserted into the gene coding for the VP22 tegument protein [54 (link)], were propagated on Vero cells, as previously reported [37 (link)]. Measle virus (ATCC VR-24) was grown on VERO/hSLAM cells, while HPIV-2 (ATCC VR-92), HCoV-229E (ATCC VR-740), and SARS-CoV-2 (strain VR PV10734, kindly donated by the Lazzaro Spallanzani Hospital of Rome, Italy) and Enterovirus C (Sb-1, poliovirus Sabin strain chat, ATCC VR-1562) on Vero cell line.

Vero cells (ATCC CCL-81, Manassas, Virginia, United States) were cultivated in Dulbecco’s Modified Eagle Medium (DMEM) with 4.5 g/L glucose (Microtech, Naples, Italy) supplemented with a penicillin/streptomycin solution (Himedia, Naples, Italy) and 10% Fetal Bovine Serum (FBS, Microtech). HSV-1 (strain SC16), containing a lacZ gene driven by the cytomegalovirus IE-1 promoter to express beta-galactosidase, was grown on a Vero cell monolayer, as previously reported [29 (link)]. An acyclovir-resistant HSV-1 strain was selected in Vero cells receiving suboptimal acyclovir (ACV, Sigma-Aldrich) treatment.

African green monkey kidney epithelial cell lines (Vero CCL-81, Manassas, VA, USA) were acquired from the American Type Culture Collection (ATCC), cultivated in Dulbecco’s modified Eagle’s medium (DMEM) with 4.5 g/L glucose (Microtech, Naples, Italy) supplemented with 10% heat-inactivated fetal bovine serum (FBS, Microgem, Naples, Italy), 2 mM L-glutamine (Microtech), and 100 IU/mL of penicillin–streptomycin solution (Himedia, Naples, Italy), and maintained at 37 °C in a humidified atmosphere with 5% CO₂. All described viral strains were propagated on Vero cell lines: HSV-1 (strain SC16), HSV-1expressing the VP22-green fluorescent protein, HSV-2 (strain 333), poliovirus type 1 (PV-1 strain CHAT), human coronavirus 229E (HCoV-229E strain VR-740), and SARS-CoV-2 (strain VR-PV10734; kindly provided by Lazzaro Spallanzani Hospital, Rome, Italy) [58 (link)]. The experiments involving SARS-CoV-2 were carried out in a biosafety level 3 (BSL-3) containment laboratory (University of Salerno) according to World Health Organization (WHO) recommendations.