One of the curious findings from the original randomized trials of mRNA vaccines was an explosive rate of early infection after the first injection as compared with placebo.
In a recent paper from Sfera et al, the description of pathological syncytia or fusion between immune cells is described: “The LNP technology, to put it simply, mimics viral envelopes with externalized phosphatidylserine (ePS), a universal “eat me” signal, that directs immune cells to engulf the particle.
  Sfera A, Thomas KG, Sfera DO, Anton JJ, Andronescu CV, et al. (2022) Do Messenger RNA Vaccines Induce Pathological Syncytia?. Int J Pathol Clin Res 8:137. doi.org/10.23937/2469-5807/1510137 However, as ePS is also a potential “fuse me” signal, LNP may inadvertently facilitate the formation of pathological syncytia. Moreover, ePS may activate a disintegrin and metalloprotease 10 and 17 (ADAM10) (ADAM 17), master regulators of syncytia formation, contributing further to the unintended consequence of cell-cell fusion……