Controlled chondrogenesis from adipose-derived stem cells by recombinant transforming growth factor-ß3 fusion protein in peptide scaffolds.

Adipose-derived stem cells (ADSCs) are promising for cartilage repair due to their easy accessibility and chondrogenic potential. Although chondrogenesis of transforming growth factor-ß (TGF-ß) mediated mesenchymal stem cells (MSCs) is well established in vitro, clinical tissue engineering requires effective and controlled delivery of TGF-ß in vivo. In this work, a self-assembled peptide scaffold was employed to construct cartilages in vivo through the chondrogenesis from ADSCs controlled by recombinant fusion protein LAP-MMP-mTGF-ß3 that was transfected by lentiviral vectors. During this course, the addition of matrix metalloproteinases (MMPs) can trigger the release of mTGF-ß3 from the recombinant fusion protein of LAP-MMP-mTGF-ß3 in the combined scaffolds, thus stimulating the differentiation of ADSCs into chondrogenesis. The specific expression of cartilage genes was analyzed by real-time polymerase chain reaction and Western blot. The expression of chondrocytic markers was obviously upregulated to a higher level compared to the one by commonly used TGF-ß3 alone. After 3 weeks of in vitro culturing, the hybrids with differentiated chondrogenesis were then injected subcutaneously into nude mice and retrieved after 4 weeks of culturing in vivo. Histological analysis also confirmed that the recombinant fusion protein was more effective for the formation of cartilage matrix than the cases either with TGF-ß3 alone or without LAP-MMP-mTGF-ß3 (P<0.05). This study demonstrates that controlled local delivery of the LAP-MMP-mTGF-ß3 constructs can accelerate differentiation of ADSCs into the cartilage in vivo, which indicates the great potential of this hybrid in rapid therapy of osteoarthritis.

Effects of TGF beta1 autocrine blockage on osteosarcoma cells.

OBJECTIVE: To evaluate the effects of transforming growth factor beta1 (TGFbeta1) autocrine blockage on proliferation activity and drug sensitivity of osteosarcoma. METHODS; Northern blot, MTT determination, and 3H thymidine incorporation were used to investigate the effects of antisense TGF beta1 gene on osteosarcoma. RESULTS: The proliferation of osteosarcoma cells transfected by antisense TGF beta1 gene was suppressed markedly, and adriamycin sensitivity was significantly increased. CONCLUSION: Blockage of osteosarcoma cells TGF beta1 autocrine loop inhibits cell proliferation and enhances chemotherapy sensitivity.