ABSTRACT… In this study, mRNA-1273 intramuscularly given to pregnant mice rapidly circulated in maternal blood and crossed the placenta within one hour to spread in fetal circulation. Although spike mRNA in fetal circulation faded away within 4-6 hours, it could accumulate in fetal tissues, mainly the liver and get translated into spike protein. Transplacental mRNA-1273 proved immunogenic in the fetuses, as postnatally equipped with anti-spike IgM, paternal allotypic anti-spike IgG2a and heightened anti-spike cellular immunity. Gestationally administered, mRNA-1273 had a dose-dependent effect on its transplacental transfer and immunogenicity in the fetuses, with higher mRNA-1273 doses leading to increased transplacental mRNA-1273 passage and greater serum titers of endogenous anti-spike IgM/IgG generated by the fetuses. Thus, gestationally maternal mRNA-1273 vaccination might endow the newborns with not only passive but also active anti-spike immunity.
VLA Comment: Although it is enlightening to expose the fact that the mRNA vaccines cross the placenta barrier, This study is crazy–stating that the transplacental inoculation of the fetus “endows” it with protection!