Although vaccine-specific factors can also produce discrete adverse events independent of spike, such as, for instance, the interaction between PF4 and the adenoviral polyanion capsid [27], several studies show that spike particles alone, through downstream cascade effects, can account for the other explanatory pathways: that is, de novo autoimmunity [127,128], the reactivation of latent viruses [46,56,129,130], and direct endothelial or tissue injury [1,2,131]. Here, PF4 is linked to Autoimmunity.