As we intended these organ chips for use in the fight against COVID-19, we also understood the importance of the expression of ACE-2, which is particularly relevant since it had been shown that although Vero cells not expressing ACE-2 could become infected with SARS-CoV-2, this different mechanism of infection provided poor concurrence with human drug trials.3 Through both immunohistochemistry and ELISA, we were able to demonstrate the expression of ACE-2 and to show how modulation of cytokine activity could affect the expression of ACE-2 with or without changes to vascular permeability. Here, ACE2 is linked to infection.