“Were embryonic stem cells used in any way in the development of this vaccine?”
Pfizer did not use fetal stem lines for development but did for testing.
“Stem” should have been “cell”.
protein test & pseudovirus HEK293 cells
Vogel et al., bioRxiv 8Sept2020
“Pfizer did not use fetal stem lines for development but did for testing.”
They did not use fetal stem cells for development.
They did not use fetal stem cells for testing.