Arterially transplanted mesenchymal stem cells in a mouse reversible unilateral ureteral obstruction model: in vivo bioluminescence imaging and effects on renal fibrosis.

Background: Chronic kidney disease (CDK) is a worldwide health problem, but there is currently no effective treatment that can completely cure this disease. Recently, studies with mesenchymal stem cells (MSCs) on treating various renal diseases have shown breakthroughs. This study is to observe the homing features of MSCs transplanted via kidney artery and effects on renal fibrosis in a reversible unilateral ureteral obstruction (R-UUO) model.

Methods: Thirty-six Balb/c mice were divided into UUO group, UUO-MSC group, and sham group randomly, with 12 mice in each group. The MSCs had been infected by a lentiviral vector to express stably the luciferase reporter gene and green fluorescence protein genes (Luc-GFP-MSC). Homing of MSCs was tracked using in vivo imaging system (IVIS) 1, 3, 14, and 28 days after transplantation. Imaging results were verified by detecting GFP expression in frozen section under a fluorescence microscope. E-cadherin, α-SMA, TGF-β1, and TNF-α mRNA expression in all groups at 1 and 4 weeks after transplantation were analyzed by quantitative PCR.

Results: Transplanted Luc-GFP-MSCs showed increased Luciferase expression 3 days after transplantation. The expression decreased from 7 days, weakened thereafter and could not be detected 14 days after transplantation. Quantitative PCR results showed that all gene expressions in UUO group and UUO-MSC group at 1 week had no statistical difference, while at 4 weeks, except TGF-β expression (P > 0.05), the expression of E-cadherin, α-SMA, and TNF-α in the above two groups have statistical difference (P < 0.01).

Conclusion: IVIS enables fast, noninvasive, and intuitive tracking of MSC homing in vivo. MSCs can be taken home to kidney tissues of the diseased side in R-UUO model, and renal interstitial fibrosis can be improved as well.