SOD2 and lentivirus infection: It is interesting that we observed significant changes of SOD2 expression in MECs isolated from both heart and aorta with the lentivirus infection, while there were no significant changes from the whole heart, aorta and other tissues, this may be explained by the fact that the percentage of endothelial cells from the whole tissue is very low, and the expression changes from such a small percentage of endothelial cells cannot be distinguished from the whole tissue.