And cytotoxicity - with the second shot, the body will have cytotoxic T cells which could target some of the transfected cells. But, why not to be worried: -

And cytotoxicity - with the second shot, the body will have cytotoxic T cells which could target some of the transfected cells. But, why not to be worried: - It's a normal process and most cells will be replaced. - The effects would be tiny, especially compared to an infection with the real thing. If this was causing widespread issues, we would know by now. - All studies done so far indicate that only a very small amount will enter systemic circulation. It's a classic risk tradeoff, and the risks of taking the vaccine are much smaller than the risk of getting the real infection (billions of viruses replicating vs. one-time dose, real spike protein vs. stabilized spike protein).