Cryopreserved PBMCs were thawed and washed twice with 10 ml of fluorescence-activated cell sorting (FACS) buffer (1× PBS containing 2% FBS and 1 mM EDTA) and resuspended in 100 μl of PBS containing
Zombie UV LIVE/DEAD dye at 1:200 dilution (BioLegend, #423108) and incubated at room temperature for 15 min. After washing, cells were incubated with an antibody cocktail for 1 hour protected from light on ice. The following antibodies were used: IgD phycoerythrin (PE; Southern Biotech, #2030–09), IgM peridinin chlorophyll protein–Cy5.5 (BioLegend, #314512), CD20 allophycocyanin-H7 (BD Biosciences, #560734),
CD27 PE-Cy7 (BioLegend, #302838), CD14 brilliant violet (BV) 650 (BioLegend, #301836),
CD16 BV650 (BioLegend, #302042), IgG brilliant UV 395 (BD Biosciences, #564229),
CD3 BV650 (BD Biosciences, #563916),
CD21 PE-CF594 (BD Biosciences, #563474), Alexa Fluor 488–labeled Beta Spike protein (antibodies-online, #ABIN6963740), Alexa Fluor 647– labeled Omicron Spike protein (Sino Biological, #40589-V08H26), and BV421-l abeled Wuhan Spike protein (Sino Biological, #40589-V27B-B). All antibodies were used as per the manufacturer’s instruction, and the final concentration of each probe was 0.1 μg/ml. Cells were washed twice in FACS buffer and immediately acquired on a
BD FACSAria III. FlowJo software v10 (TreeStar Inc.) was used for data analysis.
Arunachalam P.S., Feng Y., Ashraf U., Hu M., Walls A.C., Edara V.V., Zarnitsyna V.I., Aye P.P., Golden N., Miranda M.C., Green K.W., Threeton B.M., Maness N.J., Beddingfield B.J., Bohm R.P., Scheuermann S.E., Goff K., Dufour J., Russell-Lodrigue K., Kepl E., Fiala B., Wrenn S., Ravichandran R., Ellis D., Carter L., Rogers K., Shirreff L.M., Ferrell D.E., Deb Adhikary N.R., Fontenot J., Hammond H.L., Frieman M., Grifoni A., Sette A., O’Hagan D.T., Van Der Most R., Rappuoli R., Villinger F., Kleanthous H., Rappaport J., Suthar M.S., Veesler D., Wang T.T., King N.P, & Pulendran B. (2022). Durable protection against the SARS-CoV-2 Omicron variant is induced by an adjuvanted subunit vaccine. Science translational medicine, 14(658), eabq4130.