it's certainly true that people vaccinated with mRNA vaccines do shed spike protein

mRNA technology pioneer [Luigi Warren] says Covid-19 vaccinated people can shed spike protein, Twitter says delete this

https://www.indiatoday.in/technology/news/story/mrna-technology-pioneer-says-covid-19-vaccinated-people-can-shed-spike-protein-twitter-says-delete-this-1809062-2021-05-31

Luigi Warren twitter:

https://twitter.com/luigi_warren