REN and pulmonary fibrosis: SARS-CoV-2 virus binds to angiotensin converting enzyme 2 (ACE2) and alters renin-angiotensin system activities, thus leading to enhanced inflammation (increased levels of VEGF, IP-10/CXCL10, MCP-3/CCL7, IL-6, IL-1, ROS etc.)and development of pulmonary fibrosis [42].