Understanding COVID-19 Autoimmunity in 3 Minutes

Medical Doctor and Researcher Dr. Philip McMillan proposes that autoimmunity to ACE-2 and ACE is triggered by the viral infection in SARS-COV-2. It was postulated that in people with high levels of soluble ACE-2, the viral spike protein binding tightly together with ACE-2 could be endocytosed by macrophages which would function as antigen-presenting cells. The whole viral protein could be proteolytically cleaved, including ACE-2, tightly attached to the viral spike protein, possibly producing new epitopes for antibody generation. ACE-2 has a 42% homology with ACE, which could mean that autoantibodies that were formed against ACE-2 might cross- react with ACE as well. In this circumstance, the antibodies would target both ACE and ACE-2 cellular attached enzymes, leading to severe inflammation throughout the body, especially on lung endothelial cells. Consistent with this hypothesis, very recent data documented higher levels of soluble ACE-2 in the serum of critically ill CoVid-19 patients.