Effect of Transplanting Various Concentrations of a Composite of Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells and Hyaluronic Acid Hydrogel on Articular Cartilage Repair in a Rabbit Model.
BACKGROUND
Mesenchymal stem cells (MSCs) are known to have therapeutic potential for cartilage repair. However, the optimal concentration of MSCs for cartilage repair remains unclear. Therefore, we aimed to explore the feasibility of cartilage repair by human umbilical cord blood-derived MSCs (hUCB-MSCs) and to determine the optimal concentrations of the MSCs in a rabbit model.


METHODS
Osteochondral defects were created in the trochlear groove of femur in 55 rabbits. Four experimental groups (11 rabbits/group) were treated by transplanting the composite of hUCB-MSCs and HA with various MSCs concentrations (0.1, 0.5, 1.0, and 1.5 x 107 cells/ml). One control group was left untreated. At 4, 8, and 16 weeks post-transplantation, the degree of cartilage repair was evaluated grossly and histologically.


RESULTS
Overall, transplanting hUCB-MSCs and HA hydrogel resulted in cartilage repair tissue with better quality than the control without transplantation (P = 0.015 in 0.1, P = 0.004 in 0.5, P = 0.004 in 1.0, P = 0.132 in 1.5 x 107 cells/ml). Interestingly, high cell concentration of hUCB-MSCs (1.5×107 cells/ml) was inferior to low cell concentrations (0.1, 0.5, and 1.0 x 107 cells/ml) in cartilage repair (P = 0.394,P = 0.041, P = 0.699, respectively). The 0.5 x 107 cells/ml group showed the highest cartilage repair score at 4, 8 and 16 weeks post transplantation, and followed by 0.1x107 cells/ml group or 1.0 x 107 cell/ml group.


CONCLUSIONS
The results of this study suggest that transplantation of the composite of hUCB-MSCs and HA is beneficial for cartilage repair. In addition, this study shows that optimal MSC concentration needs to be determined for better cartilage repair.
Department of Orthopedic Surgery, Chung-Ang University Hospital, Chung-Ang University College of Medicine, 102 Heukseok-ro, Dongjak-gu, Seoul 06973, South Korea.
Yong-Beom
http://orcid.org/0000-0002-3741-2311
YB
Park
Department of Orthopaedic Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, South Korea.|Stem Cell & Regenerative Medicine Research Institute, Samsung Medical Center, 81 Irwon-ro, Gangnam-gu, Seoul 06351, South Korea.|Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, South Korea.
Chul-Won
CW
Ha
Department of Orthopaedic Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, South Korea.|Stem Cell & Regenerative Medicine Research Institute, Samsung Medical Center, 81 Irwon-ro, Gangnam-gu, Seoul 06351, South Korea.
Jin-A
JA
Kim
Department of Orthopaedic Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, South Korea.|Stem Cell & Regenerative Medicine Research Institute, Samsung Medical Center, 81 Irwon-ro, Gangnam-gu, Seoul 06351, South Korea.
Ji-Heon
JH
Rhim
Department of Orthopedic Surgery, Jeju National University Hospital, Jeju National University School of Medicine, 15 Aran 13-gil, Jeju-si 63241, South Korea.
Yong-Geun
YG
Park
Department of Orthopaedic Surgery, Ajou University Hospital, Ajou University School of Medicine, 164 World cup-ro, Yeongtong-gu, Suwon 16499, South Korea.
Jun Young
JY
Chung
Department of Orthopedic Surgery, Chung-Ang University Hospital, Chung-Ang University College of Medicine, 102 Heukseok-ro, Dongjak-gu, Seoul 06973, South Korea.
Han-Jun
HJ
Lee
D000818:Animals; D002358:Cartilage, Articular / Q000187:drug effects* / Q000502:physiology*; D005312:Fetal Blood / Q000502:physiology*; D006801:Humans; D006820:Hyaluronic Acid / Q000627:therapeutic use*; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000627:therapeutic use*; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods; D059630:Mesenchymal Stem Cells / Q000502:physiology*; D011817:Rabbits; D023822:Tissue Engineering / Q000379:methods; D014945:Wound Healing / Q000502:physiology*
D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D006820:Hyaluronic Acid