ACE2 and hereditary angioedema: From the pioneer studies showing the relevance of the kinin system in Plasmodium infections in the 1970s, passing through the elegant contributions by Dr. Regoli about the effects of bacterial LPS on de novo induction of kinin B1 receptors in the 1980s, we arrived in the 1990s with a massive development of kinin antagonists, reaching the 2000s with the approval of icatibant for the treatment of hereditary angioedema, finally meeting the year of 2020 with startling evidence about the relevance of ACE2 and kinins for Covid-19 burden.