I thought that the Spike Protein gets gobbled up by the immune system as it swirls through the circulatory system. Also, the host cells that manufacture the Spike Protein are destroyed by the cytoxic T-cells that release destructive molecules that destroys the host cell and stops the manufacture process.
There isn’t any question that the vaccine nanoparticles are ending up in the spleen, ovaries and other organs.
I read a news item that said the spike proteins that your cells manufactured, per the commands of the mRNA in the shot, would stay embedded in the cell membranes. Maybe that’s the case for most of the spikes, but a recent study did show loose spike proteins in the blood plasma of its subjects.