Immune response of newborn mice to COVID-19 mRNA vaccine

Both forms of the vaccine induced detectable anti-RBD antibodies, with significantly higher levels observed in neonatal mice receiving the mRNA vaccine.

• Neonatal mice were immunized with either the recombinant receptor binding domain (rRBD) or the mRNA encoded RBD (RBD-mRNA-LNP) vaccine.
• Both vaccines were administered twice, three weeks apart.
• The mRNA vaccine resulted in significantly higher levels of IgG antibodies against RBD compared to the recombinant protein vaccine.
• The mRNA vaccine also demonstrated more potent inhibition of RBD binding to ACE2 in neonatal mice.
• These findings suggest that the mRNA vaccine platform may elicit superior immune responses in neonates compared to the recombinant protein platform.

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