MCEMP1 and myocarditis: In addition, as we have observed that 2 of the 5 severe COVID-19 patients in our cohort had indications of cardiac involvement, where one had myocardial infarction and the other had myocarditis with cardiomyopathy, it may also be worthwhile to investigate whether cardiac involvement caused by SARS-CoV-2 infection is related to MCEMP1 expression.