Transplantation of induced mesenchymal stem cells for treating chronic renal insufficiency

Abstract

Discovering a new cell transplantation approach for treating chronic renal insufficiency is a goal of many nephrologists. In vitro-cultured peripheral blood mononuclear cells (PBMCs) were reprogrammed into induced mesenchymal stem cells (iMSCs) by using natural inducing agents made in our laboratory. The stem cell phenotype of the iMSCs was then identified. Unilateral ureteral obstruction (UUO) was used to create an animal model of chronic renal insufficiency characterized by renal interstitial fibrosis. The induced and non-induced PBMCs were transplanted, and the efficacy of iMSCs in treating chronic renal insufficiency was evaluated using a variety of methods. The ultimate goal was to explore the effects of iMSC transplantation on the treatment of chronic renal insufficiency, with the aim of providing a new therapeutic modality for this disease.

Fig 1. Peripheral blood mononuclear cells (PBMCs).

A, B: Non-induced PBMCs at 0 h and 72 h, respectively. C, D: Induced PBMCs at 0 h and 72 h, respectively. Fig 1D shows that induced PBMCs cultured for 72 h have grown into colonies with higher numbers and larger sizes of cells.

Fig 2. Evaluation of relative OCT4 and NANOG gene expression via quantitative PCR.

The relative expression levels of OCT4 and NANOG increased significantly in the induced PBMCs.

Fig 3. Flow cytometric detection of OCT4 and NANOG protein expression in the non-induced and induced PBMCs.

A, B, C, D: OCT4 protein expression. E, F, G, H: NANOG protein expression. A, B, E, F: Non-induced PBMCs. C, D, G, H: Induced PBMCs. A, C, E, G: Isotype Control. After induction, the rates of OCT4 and NANOG protein expression were significantly increased.

Fig 4. Changes in kidney function.

A: Normal control group: GFR is 31.1; B: UUO control group: GFR decreases to 8.6; C: non-induced group: GFR is 15.0; D: induced group: GFR returns to 30.9. The renal blood flow increased significantly in the induced group at 4 weeks.

Fig 5. Expression of TGF-β1 as shown by immunohistochemistry.

A: Normal control group; B: UUO control group; C: non-induced group; D: induced group. The expression of TGF-β1 was lower in the induced group than in the non-induced and UUO control groups.

Fig 6. Semi-quantitative PCR detection of TGF-β1 expression.

M, Marker; 1, normal control group; 2, induced group; 3, non-induced group; 4, UUO control group. TGF-β1 expression was significantly lower in the induced group than in the UUO control group and the non-induced group.

Fig 7. Kidney tissue SEM results (3.81 × 1000 times).

A. Normal group: normal renal tubular epithelial cells; B. UUO control group: extensive renal interstitial fibrosis with fibroblast proliferation; C. non-induced group: renal interstitial fibrosis remains widespread; D. induced groups: no obvious renal interstitial fibrosis and visible normal tubular and tubular epithelial cells.