Novel gene therapy CM-YAPon protects the mouse heart from myocardial infarction - Virus Test

Myocardial infarction (MI), which affects about 3 million people globally each year, permanently damages the heart and reduces cardiac function1. Recent studies have indicated that activating YAP in cardiomyocytes (CMs) promotes cardiac regeneration and mitigates pathological remodeling in mouse and pig MI models2,3. To precisely control YAP activity in vivo and encourage its clinical application, we developed an adeno-associated virus 9 (AAV9)-based therapy, termed CM-YAPon, which triggers YAP activation in CMs upon exposure to a small molecule LMI070. One dose of LMI070 in mice induced a transient expression of active YAP (YAP5SA), which was subsequently degraded within a week. Consistent with earlier findings, YAP activation after injury improved cardiac function. Interestingly, administering a single LMI070 injection two weeks before MI provided lasting cardioprotection, which diminished by four weeks after the transient YAP activation, by reducing non-CMs cell death and enhancing cardiac function. Taken together, our novel gene therapy CM-YAPon presents a promising avenue for developing protective strategies against MI-induced cardiac injury. Overall design: AAV9 virus expressing GFP and YAPon was administrated to P7 mice by intraperitoneal injection. Two weeks later, we collected mouse heart for single nucleus RNA sequencing. Nuclei were collected from the entire heart using a Chromium Nuclei Isolation Kit (10x Genomics, PN-1000493). In total, 20,000 nuclei per sample were loaded onto the 10x Genomics Chromium Controller to obtain the gel beads in emulsion. The sequencing libraries were then prepared according to the manufacturer's protocols for the Single Cell 3' Reagents Kit (10x Genomics, Chromium Next GEM Single Cell 3' Kit version 3.1, 1000269). Sequencing was performed by using the NovaSeq XPlus instrument.