UCLA

Coronavirus disease 2019 (COVID-19) is a pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 is defined by respiratory symptoms, but cardiac complications including viral myocarditis are also prevalent. Although ischemic and inflammatory responses caused by COVID-19 can detrimentally affect cardiac function, the direct impact of SARS-CoV-2 infection on human cardiomyocytes is not well understood. Here, we utilize human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) as a model to examine the mechanisms of cardiomyocyte-specific infection by SARS-CoV-2. Microscopy and RNA sequencing demonstrate that SARS-CoV-2 can enter hiPSC-CMs via ACE2. Viral replication and cytopathic effect induce hiPSC-CM apoptosis and cessation of beating after 72 h of infection. SARS-CoV-2 infection activates innate immune response and antiviral clearance gene pathways, while inhibiting metabolic pathways and suppressing ACE2 expression. These studies show that SARS-CoV-2 can infect hiPSC-CMs in vitro, establishing a model for elucidating infection mechanisms and potentially a cardiac-specific antiviral drug screening platform.