Elisa for sars cov 2 s

The 2nd generation lentiviral packaging plasmid, psPAX2 (Addgene), a reporter plasmid pUCGFP-Luc (Addgene), and parental or mutant pAbVec-SARS2-S were transfected into HEK293 cells to produce pseudotyped viruses. Briefly, cells plated in 6-well plates the previous day were transfected with three plasmids (1 ug each per well) using Lipofectamine 2000 (Thermo Fisher, Waltham, MA). Following overnight incubation, media was replaced with fresh media containing 5% FBS, and the cells were further incubated for 48 hrs. Supernatants were collected, and cell debris was removed by centrifugation at 400xg for 10 min. Quantitation of pseudotyped viruses was performed using an HIV p24 assay kit (Takara Bio) or ELISA for SARS-CoV-2 S (Sino Biological, Wayne, PA) before storing at −80°C.

The second-generation lentiviral packaging plasmid psPAX2 (Addgene), a reporter plasmid pUCGFP-Luc (Addgene), and parental or mutant pAbVec-SARS2-S were transfected into HEK293 cells to produce pseudotyped viruses. Briefly, cells plated in 6-well plates the previous day were transfected with three plasmids (1 μg each per well) using Lipofectamine 2000 (Thermo Fisher, Waltham, MA). Following overnight incubation, medium was replaced with fresh medium containing 5% FBS, and the cells were further incubated for 48 h. Supernatants were collected, and cell debris was removed by centrifugation at 400 × g for 10 min. Quantitation of pseudotyped viruses was performed using an HIV p24 assay kit (TaKaRa Bio) or ELISA for SARS-CoV-2 S (Sino Biological, Wayne, PA) before storing at –80°C.

The second-generation lentiviral packaging plasmid psPAX2 (Addgene), a reporter plasmid pUCGFP-Luc (Addgene), and parental or mutant pAbVec-SARS2-S were transfected into HEK293 cells to produce pseudotyped viruses. Briefly, cells plated in 6-well plates the previous day were transfected with three plasmids (1 μg each per well) using Lipofectamine 2000 (Thermo Fisher, Waltham, MA). Following overnight incubation, medium was replaced with fresh medium containing 5% FBS, and the cells were further incubated for 48 h. Supernatants were collected, and cell debris was removed by centrifugation at 400 × g for 10 min. Quantitation of pseudotyped viruses was performed using an HIV p24 assay kit (TaKaRa Bio) or ELISA for SARS-CoV-2 S (Sino Biological, Wayne, PA) before storing at –80°C.