The Use Of Chitosan Based Hydrogel For Enhancing The Therapeutic Benefits Of Adipose-Derived MSCs ForAcute Kidney Injury

Objiective Transplantation of mesenchymal stem cells (MSCs) has beenreported a great therapeutic potential for acute kidney injury (AKI). However, thetherapeutic benefits are limited due to the low retention and survival of transplantedcells within target sites. Thermosensitive chitosan chloride (CSCI) hydrogel as aninjectable scaffold, it has a well biocompatible and biodegradable, and it has beenwidely used in tissue engineering. In this study, CSCI hydrogel was explored asinjectable scaffold for adipose-derived MSCs (ADMSCs) delivery intoischemia/reperfusion (I/R) induced acute kidney injury (AKI).Methods In vitro: Isolation, culture and flow cytometry analysis of ADMSCs,and the ADMSCs were lentivirally transduced to express both firefly luciferase (Fluc)and monomeric red fluorescent protein (mRFP), and adipogenic and osteogenicdifferentiation assays. Thermosensitive CSCI hydrogels was prepared, and Live/Deadstaining evaluated the biocompatible of CSCI hydrogel. In vivo: The adult maleSprague-Dawley rats (150-200g) were subjected to renal ischemia/reperfusion (I/R)injury model.thermosensitive CSCI hydrogels with/without ADMSCs were injectedinto the rat AKI models. Dihydroethidium staining was used to detect the number ofROS in vivo. In order to track ADMSCs in vivo, the retention and survival of(fluc-mrfp) labeled ADMSCs were assessed using bioluminescence imaging. HEstaining and serum levels of creatinine (CRE) and blood urea nitrogen (BUN) wereassessed the renal tissue injury and renal function. Differentiation behaviors ofADMSCs were investigated using Immunofluorescent and immunohistochemicalstaining. Proliferation and apoptosis of host renal cell in vivo were characterized byPCNA and TUNEL staining.Result In vitro: ADMSCs exhibited the fibroblast-like morphology, flow cytometric analysis indicated that ADMSCs were positive for CD29, CD90andnegative for CD34, CD45and CD31. The successfully transduced ADMSCs could beviewed strong expression fluc-mrfp reporter gene, and exhibited adipogenic andosteogenic differentiation.Live/Dead staining indicated the cell death rarely occursowing to the CSCI hydrogel. In vivo: results suggested that CSCI hydrogels couldimprove the retention and survival of grafted ADMSCs, moreover, CSCI hydrogelscould enhance the proliferation activity and reduce apoptosis of host renal cells. At4weeks, significant improvement of the renal function, microvessel density and tubularcell proliferation were observed in CSCI hydrogels with ADMSCs groups.Conclusion The application of thermosensitive CSCI hydrogel as scaffold forADMSCs delivery into renal region could resolve the main obstacle of celltransplantation for acute kidney injury (AKI). Therefore, CSCl hydrogel is a potentialcell carrier for treatment of AKI.