All CD20+ B and CD8+ T cell depletion studies followed by wild-type SARS-CoV-2 challenge were carried out by adapting a previously published approach. B cells were depleted from hACE2 transgenic mice through the intraperitoneal (i.p.) administration of 50 μg of
anti-CD20 antibody (BioLegend
SA271G2) at 72 h (−3 days) and 24 h (−1 day) before vaccination with LUNAR-COV19. For CD8+ T cell depletion, 5 μg of anti-CD8
+ antibody (Bio X Cell, Cat#BE0061) was injected i.p. at −3 days and −1 day before challenge with SARS-CoV-2. For control mice, isotype IgG2b mouse control antibody (Bio X Cell, Cat#BE0090) was similarly injected. Successful depletions of CD20
+ B and/or CD8
+ T cells were confirmed via flow cytometry. Briefly, 24 h after the second injection of anti-CD20
+ and/or anti-CD8
+ antibodies, sub-mandibular blood was stained with AF488-conjugated anti-mouse CD45R (BD, Cat#557669),
APC-conjugated anti-mouse CD3 (BD, Cat#565643), and
BUV395-conjugated anti-mouse CD8b antibodies (BD, Cat#74027).
de Alwis R., Gan E.S., Chen S., Leong Y.S., Tan H.C., Zhang S.L., Yau C., Low J.G., Kalimuddin S., Matsuda D., Allen E.C., Hartman P., Park K.J., Alayyoubi M., Bhaskaran H., Dukanovic A., Bao Y., Clemente B., Vega J., Roberts S., Gonzalez J.A., Sablad M., Yelin R., Taylor W., Tachikawa K., Parker S., Karmali P., Davis J., Sullivan B.M., Sullivan S.M., Hughes S.G., Chivukula P, & Ooi E.E. (2021). A single dose of self-transcribing and replicating RNA-based SARS-CoV-2 vaccine produces protective adaptive immunity in mice. Molecular Therapy, 29(6), 1970-1983.