Bone marrow-derived cells can acquire renal stem cells properties and ameliorate ischemia-reperfusion induced acute renal injury

BACKGROUND: Bone marrow (BM) stem cells have been reported to contribute to tissue repair after kidney injury model. However, there is no direct evidence so far that BM cells can trans-differentiate into renal stem cells. METHODS: To investigate whether BM stem cells contribute to repopulate the renal stem cell pool, we transplanted BM cells from transgenic mice, expressing enhanced green fluorescent protein (EGFP) into wild-type irradiated recipients. Following hematological reconstitution and ischemia-reperfusion (I/R), Sca-1 and c-Kit positive renal stem cells in kidney were evaluated by immunostaining and flow cytometry analysis. Moreover, granulocyte colony stimulating factor (G-CSF) was administrated to further explore if G-CSF can mobilize BM cells and enhance trans-differentiation efficiency of BM cells into renal stem cells. RESULTS: BM-derived cells can contribute to the Sca-1(+) or c-Kit(+) renal progenitor cells population, although most renal stem cells came from indigenous cells. Furthermore, G-CSF administration nearly doubled the frequency of Sca-1+ BM-derived renal stem cells and increased capillary density of I/R injured kidneys. CONCLUSIONS: These findings indicate that BM derived stem cells can give rise to cells that share properties of renal resident stem cell. Moreover, G-CSF mobilization can enhance this effect.