Abstract
A booster vaccination is called for constraining the evolving epidemic of SARS-CoV-2. However, the necessity of a new COVID-19 vaccine is currently unclear. To compare the effect of an Omicron-matched S DNA vaccine and an ancestral S DNA vaccine in boosting cross-reactive immunities, we firstly immunized mice with two-dose of a DNA vaccine encoding the spike protein of the ancestral Wuhan strain. Then the mice were boosted with DNA vaccines encoding spike proteins of either the Wuhan strain or the Omicron variant. Specific antibody and T cell responses were measured at 4 weeks post boost. Our data showed that the Omicron-matched vaccine efficiently boosted RBD binding antibody and neutralizing antibody responses against both the Delta and the Omicron variants. Of note, antibody responses against the Omicron variant elicited by the Omicron-matched vaccine were much stronger than those induced by the ancestral S DNA vaccine. Meanwhile, CD8 + T cell responses against both the ancestral Wuhan strain and the Omicron strain also tended to be higher in mice boosted by the Omicron-matched vaccine than those in mice boosted with the ancestral S DNA vaccine, albeit no significant difference was observed. Our findings suggest that an Omicron-matched vaccine is preferred for boosting cross-protective immunities.
Keywords: Omicron-matched vaccine; T cell; antibody; booster vaccination; cross-reactivity.
【저자키워드】 antibody, T cell, booster vaccination, Omicron-matched vaccine, cross-reactivity., 【초록키워드】 SARS-CoV-2, Vaccine, COVID-19 vaccine, antibody, Antibody Response, variant, Delta, omicron, CD8, Omicron variants, variants, Spike protein, cross-reactivity, T cell, Antibody responses, Epidemic, mice, T cell responses, Omicron variant, DNA vaccines, DNA vaccine, T cell response, Neutralizing antibody response, booster, boost, booster vaccination, Spike proteins, cross-reactive, significant difference, no significant difference, RBD binding, neutralizing antibody responses, Wuhan strain, Specific, immunized mice, the spike protein, cross-protective, elicited, were measured, 【제목키워드】 Delta, strain, Against,