TNF and myocardial infarction: To confirm that injection of TNF-α in MI-mice preserved heart function through antagonizing MSC-induced M2-polarization of macrophages in vivo, we digested the heart at 4 weeks after treatments and analyzed F4/80 and CD163 for macrophages as well as CD4 (a T-helper cell marker) and CD8 (a cytotoxic T cell marker) by FACS.