Factors leading to PASC include the following: effects from acute SARS-CoV-2 injury in one or multiple organs; persistent reservoirs of SARS-CoV-2; reactivation of neurotrophic pathogens, such as herpesviruses, due to COVID-19 causing immune dysregulation; ongoing activity of primed immune cells; autoimmunity due to molecular mimicry between pathogen and host proteins [73,74]; the appearance of antibodies specific to ACE2 [75]; and an elevated number of monocytes containing SARS-CoV-2 S1 protein in both severe COVID-19 and PASC patients [76]. Here, ACE2 is linked to long COVID-19.