Objective To verify the potential of the recombinant adeno-associated virus 2 (rAAV2) vector as a strategy for human transforming growth factor β1 (hTGF-β1) gene transfer in degenerative intervertebral discs of rabbit, to investigate the gene transduction efficacy and to quantify the biologic effects on the proteoglycan level after gene transferring. Methods Rabbit models of disc degeneration were established by injecting the 25 μL fibronectin fragment (Fn-f, 1 mmol/ L), 4 weeks later,saline with or without virus was injected directly into 96 lumbar discs of 24 mature New Zealand white rabbits (male or female and weighing 1.7-2.2 kg) which were divided into 3 groups (n=8). Group A received the 25 μL rAAV2-hTGF-β1 (1 × 1012 vg/mL); group B received rAAV2-enhanced green fluorescent protein (rAAV2-EGFP); and group C received PBS. Two rabbits of groups A, C were killed 1 week after injection, the immunohistochemical staining for hTGF-β1 was performed on the sl ices of nucleus pulposus (NP) tissues. At 4, 8, and 12 weeks after gene transferring, NP tissues were harvested and cultured to quantify the changes of the proteoglycan level using 35S-sulfate incorporation assay. The expression of EGFP in group B was observed 12 weeks after injection. Results Immunohistochemical staining showed that extensive and intense positive immunohisochemical staining for hTGF-β1 were seen in group A when compared with group C 1 week after gene transferring. The nucleus pulposus tissues from the group A exhibited an increased synthesis of proteoglycan, which was significantly more than that from groups B and C (P lt; 0.05), and no significant difference was observed between group B and group C. The expression of EGFP in group B was high at 12 weeks. Conclusion The discs injected with rAAV2-hTGF-β1 can highly expressed the therapeutic proteins for more than 12 weeks, it is suggested that rAAV2 should be an valid vector for transferring exogenous genes in the degenerative disc. The therapeutic factors hTGF-β1 can efficiently increase the proteoglycan synthesis of the degenerative NP cells.
Objective To review the effect of calcitonin on cartilage and subchondral bone of osteoarthritis. Methods Recent l iteratures about the effect of calcitonin on osteoarthritis was reviewed. Results Calcitonin could promotethe synthesis of important cartilage matrix such as proteoglycans and collagen II, propell ing the regeneration of cartilage and subchondral bone. Conclusion Calcitonin can protect articular cartilage through promoting the synthesis of cartilage and inhibiting its degradation.
Objective To investigate the relationship between syndecan-1 protein and malignant phenotypes of hepatocellular carcinoma (HCC). Methods forty-seven formalin-fixed sections were obtained. The syndecan-1 was measured with immunohistochemistry assay (ABC method). Results Among 47 HCC tissues, 28 (59.6%) show negative staining, the syndecan-1 negative rate in HCC with poor differentiation was higher than those with good differentiation (78.3% vs 41.7%, Ｐ＜0.05), and negative rate in large HCC was higher than in small HCC (81.0% vs 42.3%, Ｐ＜0.01), and negative rate in HCC with the presence of tumor-cells in blood was greater than in those without tumor-cells in blood (84.2% vs 42.9%, P＜0.01). No correlation was found between syndecan-1 expression and serum AFP level and Child class. Conclusion Syndecan-1 expression is correlated with the growth, differentiation, invasiveness, metastasis and progression of HCC. It is possible that syndecan-1 is a negative regulator of these malignant phenotypes of HCC, can be regarded as suppressive gene.
