CdSe/ZnS Quantum Dots-Labeled Mesenchymal Stem Cells for Targeted Fluorescence Imaging of Pancreas Tissues and Therapy of Type 1 Diabetic Rats.

Haoqi Liu,Wei Tang,Fei Pan,Yanlei Liu,Zheng Wang,Cunlei Zhang,Yongquan Shi,Haiyan Chen,Yi Bao,Yan Song,Xiaoling Xia,Chao Li,Xiangying Meng,Pinlei Lv,Daxiang Cui

doi:10.1186/s11671-015-0959-3

Abstract

Mesenchymal stem cells (MSCs) have been used for therapy of type 1 diabetes mellitus. However, the in vivo distribution and therapeutic effects of transplanted MSCs are not clarified well. Herein, we reported that CdSe/ZnS quantum dots-labeled MSCs were prepared for targeted fluorescence imaging and therapy of pancreas tissues in rat models with type 1 diabetes. CdSe/ZnS quantum dots were synthesized, their biocompatibility was evaluated, and then, the appropriate concentration of quantum dots was selected to label MSCs. CdSe/ZnS quantum dots-labeled MSCs were injected into mouse models with type 1 diabetes via tail vessel and then were observed by using the Bruker In-Vivo F PRO system, and the blood glucose levels were monitored for 8 weeks. Results showed that prepared CdSe/ZnS quantum dots owned good biocompatibility. Significant differences existed in distribution of quantum dots-labeled MSCs between normal control rats and diabetic rats (p < 0.05). The ratios of the fluorescence intensity (RFI) analysis showed an accumulation rate of MSCs in the pancreas of rats in the diabetes group, and was about 32 %, while that in the normal control group rats was about 18 %. The blood glucose levels were also monitored for 8 weeks after quantum dots-labeled MSC injection. Statistical differences existed between the blood glucose levels of the diabetic rat control group and MSC-injected diabetic rat group (p < 0.01), and the MSC-injected diabetic rat group displayed lower blood glucose levels. In conclusion, CdSe/ZnS-labeled MSCs can target in vivo pancreas tissues in diabetic rats, and significantly reduce the blood glucose levels in diabetic rats, and own potential application in therapy of diabetic patients in the near future.

Highlights

The amount of diabetic patients has been increasing rapidly
Type 1 diabetes mellitus is characterized by the permanent destruction of pancreatic β cells
The Measurement of Blood Glucose Levels To verify the treatment of mesenchymal stem cells, we investigated the level of blood glucose after Mesenchymal stem cells (MSCs) injection (10 rats of each group, including the normal control, diabetes control, and treatment groups)

Summary

Introduction

The amount of diabetic patients has been increasing rapidly. According to the latest report, in China, the proportion of diabetic patients has reached to 11.6 %, accounting for one third of global diabetic patients. Type 1 diabetes mellitus is characterized by the permanent destruction of pancreatic β cells. Up to date, regarding the therapy of type 1 diabetes, some methods have been reported. Cellbased treatments with the aim of recovering pancreatic β cell function, including the pancreas transplantation, islet transplantation, and stem cell transplantation, focusing on replacing damaged β cell populations, should be the ideal potential therapeutic pathways [2]. In 2000, a corticosteroid-free immunosuppressive regimen, the novel Edmonton protocol, enabled seven patients to remain insulin-independent for an average of 11.9 months [4]. These results are quite difficult to reproduce, and nine-year islet graft survival rates are below 10 %. Looking for new therapeutic method may be a good choice

Methods

Results

Conclusion