Abstract:OBJECTIVE: Preclinical studies have demonstrated that exogenous mesenchymal stem cells (MSCs) may ameliorate kidney damage and enhance repair of renal ischemia reperfusion injury (IRI). This review will focus on the mechanism for accelerating repair of renal IRI by MSCs. Several chemokine receptors such as CXCR4 and CD44 are related to MSCs trafficking to post-ischemic kidney. MSCs differentiate into tubular epithelial cells, which is not the predominant mechanism for repair of the damaged kidney. Instead, MSCs exert their therapeutic effect mainly through paracrine action via a variety of cytokines and microvesicles, and the paracrine actions of infused MSCs work to activate intrinsic kidney cells, promote angiogenesis, inhibit oxidative stress and reduce apoptosis, inflammation and renal fibrosis.