Effects of combined rAAV-mediated TGF-β and sox9 gene transfer and overexpression on the metabolic and chondrogenic activities in human bone marrow aspirates.
BACKGROUND
Transplantation of genetically modified bone marrow concentrates is an attractive approach to conveniently activate the chondrogenic differentiation processes as a means to improve the intrinsic repair capacities of damaged articular cartilage.


METHODS
Human bone marrow aspirates were co-transduced with recombinant adeno-associated virus (rAAV) vectors to overexpress the pleiotropic transformation growth factor beta (TGF-β) and the cartilage-specific transcription factor sox9 as a means to enhance the chondroreparative processes in conditions of specific lineage differentiation.


RESULTS
Successful TGF-β/sox9 combined gene transfer and overexpression via rAAV was achieved in chondrogenically induced human bone marrow aspirates for up to 21 days, the longest time point evaluated, leading to increased proliferation, matrix synthesis, and chondrogenic differentiation relative to control treatments (reporter lacZ treatment, absence of vector application) especially when co-applying the candidate vectors at the highest vector doses tested. Optimal co-administration of TGF-β with sox9 also advantageously reduced hypertrophic differentiation in the aspirates.


CONCLUSIONS
These findings report the possibility of directly modifying bone marrow aspirates by combined therapeutic gene transfer as a potent and convenient future approach to improve the repair of articular cartilage lesions.
Institute of Arthritis, Peking University People's Hospital, No. 11 Xizhimen Nan Road, Xicheng District, Beijing, 100044, People's Republic of China.|Center of Experimental Orthopaedics, Saarland University Medical Center, Kirrbergerstr. Bldg 37, D-66421, Homburg/Saar, Germany.
Ke
K
Tao
Center of Experimental Orthopaedics, Saarland University Medical Center, Kirrbergerstr. Bldg 37, D-66421, Homburg/Saar, Germany.
Ana
A
Rey-Rico
Center of Experimental Orthopaedics, Saarland University Medical Center, Kirrbergerstr. Bldg 37, D-66421, Homburg/Saar, Germany.
Janina
J
Frisch
Center of Experimental Orthopaedics, Saarland University Medical Center, Kirrbergerstr. Bldg 37, D-66421, Homburg/Saar, Germany.
Jagadeesh Kumar
JK
Venkatesan
Center of Experimental Orthopaedics, Saarland University Medical Center, Kirrbergerstr. Bldg 37, D-66421, Homburg/Saar, Germany.
Gertrud
G
Schmitt
Center of Experimental Orthopaedics, Saarland University Medical Center, Kirrbergerstr. Bldg 37, D-66421, Homburg/Saar, Germany.|Department of Orthopaedic Surgery, Saarland University Medical Center, Homburg/Saar, Germany.
Henning
H
Madry
Institute of Arthritis, Peking University People's Hospital, No. 11 Xizhimen Nan Road, Xicheng District, Beijing, 100044, People's Republic of China. jianhao_lin@hotmail.com.
Jianhao
J
Lin
Center of Experimental Orthopaedics, Saarland University Medical Center, Kirrbergerstr. Bldg 37, D-66421, Homburg/Saar, Germany. mmcucchiarini@hotmail.com.
Magali
M
Cucchiarini
Chondrogenesis; Combined gene transfer; Human bone marrow aspirates; Recombinant adeno-associated virus; SOX9; Transforming growth factor beta