NATURE: IMMUNOGENICITY AND REACTOGENICITY OF HETEROLOGOUS CHADOX1 NCOV-19/MRNA VACCINATION

Abstract: In this observational study we show that, in healthy adult individuals, the heterologous vaccine regimen induced spike-specific IgG, neutralizing antibodies and spike-specific CD4 T cells, the levels of which which were significantly higher than after homologous vector vaccine boost and higher or comparable in magnitude to homologous mRNA vaccine regimens.

Moreover, spike-specific CD8 T cell levels after heterologous vaccination were significantly higher than after both homologous regimens. Spike-specific T cells were predominantly polyfunctional with largely overlapping cytokine-producing phenotypes in all three regimens.

Translation: This journal article has super-interesting results, suggesting that combining a regimen of mRNA and non-mRNA vaccines may induce the best and longest-lasting protection against COVID-19. They found that “mix and match” vaccination with AstraZeneca and mRNA vaccines induces terrific immunity- both in antibody titer and T Cells.

That mix and match produced basically the same antibody response as 2 mRNA vaccines, and better than 2 AstraZeneca shots. Interestingly, T-cell immunity was significantly higher among mix and match participants- higher than in the group that got 2 mRNA vaccines.

Note: This is a small sample size and should not be used to make policy decisions, but it does provide interesting results!