IL15 and COVID-19: Together, these findings suggest that the IL15/IL15RA induction we see in COVID-19, KD and MIS-C may have distinct sources and/or target end organs: We previously showed prominent induction of IL15/IL15RA in the lung alveoli of fatal COVID-19 patients18, and here we show it in the coronary arteries and cardiomyocytes in KD.