ISL1 and infection: To determine whether ZIKV infection affects expression of cardiac-associated and mesenchymal origin cell surface markers, fcMSCs were infected with 1 MOI ZIKV for 6 h, and the expression of CD90, CD73, CD140a (PDGFRa), ISL-1, CD172a (SIRPa), cardiac Troponin-T (cardiomyocytes), CD106 (VCAM-1, vascular smooth muscle cells), and CD31 (PECAM-1, endothelial cells) were evaluated by flow cytometry 48 h post-infection (Fig 2).