TLR4 and kidney disorder: Increasing evidence has shown that macrophages play a critical role in the pathogenesis of kidney diseases,[4, 5] supported by many studies in which macrophage deletion or inactivation can protect against anti‐GBM cGN.[6, 7, 8, 9] Among macrophages, it has been well established that the M1 pro‐inflammatory macrophages are pathogenic while the M2 phenotype is renal protective in a number of kidney diseases including the anti‐GBM cGN.[4, 5, 10] However, the role and mechanism of TLR4 in macrophage‐mediated anti‐GBM cGN remain largely unclear.