ACE2 and triple-A syndrome: Certain ACE2-producing cells may also secrete ligands that bind to receptors on ACE2-negative cells, such as macrophages and neutrophils; promote the release of proinflammatory factors, including CCL2, CCL7, Hypoxia-Inducible Factor (HIF)–1a, and Type 1 Interferon (IFN-1); and exacerbate the inflammatory response during AAA formation [33, 34].