Neutralizing antibodies (nAbs) are a critical part of coronavirus disease 2019 (COVID-19) research as they are used to gain insight into the immune response to severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) infections.Among the technologies available for generating nAbs, DNA-based immunization methods Upcycled Top are an alternative to conventional protocols.In this pilot study, we investigated whether DNA-based immunization by needle injection in rabbits was a viable approach to produce a functional antibody response.We demonstrated that three doses of DNA plasmid carrying the gene encoding the full-length spike protein (S) or the receptor binding domain (RBD) of SARS-CoV-2 induced a time-dependent increase in IgG antibody avidity maturation.Moreover, the IgG antibodies displayed high cross neutralization by live SARS-CoV-2 1m SMA and pseudoviruses neutralization assays.
Thus, we established a simple, low cost and feasible DNA-based immunization protocol in rabbits that elicited high IgG avidity maturation and nAbs production against SARS-CoV-2, highlighting the importance of DNA-based platforms for developing new immunization strategies against SARS-CoV-2 and future emerging epidemics.