IntroductionAdipose-derived stem cells (ADSCs) have been isolated, expanded, and applied in the treatment of many diseases. ADSCs have also been used to treat injured articular cartilage. However, there is controversy regarding the treatment efficiency. We considered that ADSC transplantation with activated platelet-rich plasma (PRP) may improve injured articular cartilage compared with that of ADSC transplantation alone. In this study, we determined the role of PRP in ADSC transplantation to improve the treatment efficiency.MethodsADSCs were isolated and expanded from human adipose tissue. PRP was collected and activated from human peripheral blood. The effects of PRP were evaluated in vitro and in ADSC transplantation in vivo. In vitro, the effects of PRP on ADSC proliferation, differentiation into chondrogenic cells, and inhibition of angiogenic factors were investigated at three concentrations of PRP (10%, 15% and 20%). In vivo, ADSCs pretreated with or without PRP were transplanted into murine models of injured articular cartilage.ResultsPRP promoted ADSC proliferation and differentiation into chondrogenic cells that strongly expressed collagen II, Sox9 and aggrecan. Moreover, PRP inhibited expression of the angiogenic factor vascular endothelial growth factor. As a result, PRP-pretreated ADSCs improved healing of injured articular cartilage in murine models compared with that of untreated ADSCs.ConclusionPretreatment of ADSCs with PRP is a simple method to efficiently apply ADSCs in cartilage regeneration. This study provides an important step toward the use of autologous ADSCs in the treatment of injured articular cartilage.

Osteoarthritis is one of the most common diseases, and it affects 12% of the population around the world. Although the disease is chronic, it significantly reduces the patient’s quality of life. At present, stem cell therapy is considered to be an efficient approach for treating this condition. Mesenchymal stem cells (MSCs) show the most potential for stem cell therapy of osteoarthritis. In fact, MSCs can differentiate into certain mesodermal tissues such as cartilage and bone. Therefore, in the present study, we applied adipose tissue-derived MSCs to osteoarthritis treatment. This study aimed to evaluate the clinical efficiency of autologous adipose tissue-derived MSC transplantation in patients with confirmed osteoarthritis at grade II and III. Adipose tissue was isolated from the belly, and used for extraction of the stromal vascular fraction (SVF). The SVF was mixed with activated platelet-rich plasma before injection. The clinical efficiencies were evaluated by the pain score (VAS), Lysholm score, and MRI findings. We performed the procedure in 21 cases from 2012 to 2013. All 21 patients showed improved joint function after 8.5 months. The pain score decreased from 7.6±0.5 before injection to 3.5±0.7 at 3 months and 1.5±0.5 at 6 months after injection. The Lysholm score increased from 61±11 before injection to 82±8.1 after injection. Significant improvements were noted in MRI findings, with increased thickness of the cartilage layer. Moreover, there were no side-effects or complications related to microorganism infection, graft rejection, or tumorigenesis. These results provide a new opportunity for osteoarthritis treatment. Level of evidence: IV.

Abstract-Osteoarthritis is one of the most common diseases, and it affects 12% of the population around the world. Although the disease is chronic, it significantly reduces the patient's quality of life. At present, stem cell therapy is considered to be an efficient approach for treating this condition. Mesenchymal stem cells (MSCs) show the most potential for stem cell therapy of osteoarthritis. In fact, MSCs can differentiate into certain mesodermal tissues such as cartilage and bone. Therefore, in the present study, we applied adipose tissue-derived MSCs to osteoarthritis treatment. This study aimed to evaluate the clinical efficiency of autologous adipose tissue-derived MSC transplantation in patients with confirmed osteoarthritis at grade II and III. Adipose tissue was isolated from the belly, and used for extraction of the stromal vascular fraction (SVF). The SVF was mixed with activated platelet-rich plasma before injection. The clinical efficiencies were evaluated by the pain score (VAS), Lysholm score, and MRI findings. We performed the procedure in 21 cases from 2012 to 2013. All 21 patients showed improved joint function after 8.5 months. The pain score decreased from 7.6±0.5 before injection to 3.5±0.7 at 3 months and 1.5±0.5 at 6 months after injection. The Lysholm score increased from 61±11 before injection to 82±8.1 after injection. Significant improvements were noted in MRI findings, with increased thickness of the cartilage layer. Moreover, there were no side-effects or complications related to microorganism infection, graft rejection, or tumorigenesis. These results provide a new opportunity for osteoarthritis treatment. Level of evidence: IV.