Objective To evaluate the cell biological features and the effect of transplantation of transforming growth factor β3 (TGF-β3) gene-modified nucleus pulposus (NP) cells on the degeneration of lumbar intervertebral discs in vitro. Methods NP cells at passage 2 were infected by recombinant adenovirus carrying TGF-β3 (Ad-TGF-β3) gene (Ad-TGF-β3 group), and then the cell biological features were observed by cell vital ity assay, the expression of the TGF-β3 protein was determined by Western blot, the expression of collagen type II in logarithmic growth phase was determined by immunocytochemistry. The cells with adenovirus-transfected (Adv group) and the un-transfected cells (blank group) were used as controls. The model of lumbar disc degeneration was establ ished by needl ing L3, 4, L4, 5, and L5, 6 in 30 New Zealand rabbits (weighing 3.2-3.5 kg, male or female). Then Ad-TGF-β3-transfected rabbit degenerative nucleus pulposus cells (100 μL, 1 × 105/ mL, group A, n=12), no gene-modified nucleus pulposus cells (100 μL, 1 × 105/mL, group B, n=12), and phosphatebuffered sal ine (PBS, 100 μL, group C, n=6) were injected into degenerative lumbar intervertebral discs, respectively. L3, 4, L4, 5, and L5, 6 disc were harvested from the rabbits (4 in groups A and B, 2 in group C) at 6, 10, and 14 weeks respectively to perform histological observation and detect the expression of collagen type II and proteoglycan by RT-PCR. Results The viabil ity of nucleus pulposus cells was obviously improved after transfected by recombinant Ad-TGF-β3 gene. At 3, 7, and 14 days after transfected, TGF-β3 expression gradually increased in nucleus pulposus cells. The positive staining of collagen type II was seen in Ad-TGF-β3 group, and the positive rate was significantly higher than that of Adv group and blank group (P lt; 0.05). The disc degeneration in group A was sl ighter than that in groups B and C. The expressions of collagen type II mRNA and proteoglycan mRNA in group A were significantly higher than those in groups B and C at 6, 10, and 14 weeks (P lt; 0.05). Conclusion TGF-β3 can improve the biological activity of NP cells and promote the biosynthesis of collagen type II and proteoglycan in intervertebral discs, alleviate the degeneration of intervertebral discs after transplantation.
Objective
To investigate the relationship between the volume of bone-graft and fusion efficacy in posterior lumbar interbody fusion and internal fixation of spondylolisthesis.
Methods
Between May 2004 and June 2007, 79 patients with spondylolisthesis were treated with posterior lumbar interbody fusion and internal fixation. The patients were randomly divided into 3 groups according to the volume of bone-graft for interbody fusion: group A (n=27), 5 bone granules/ cm3 on average; group B (n=26), 11 bone granules/cm3 on average; and group C (n=26), 25 bone granules/cm3 on average. There was no significant difference in gender, age, disease duration, affected segment, and the degree of vertebral slip among 3 groups (P gt; 0.05). The volume of bone-graft, the fusion rate, the loss of intervertebral height, and the incidence of internal fixation failure were compared among 3 groups.
Results
All cases were followed up 24-43 months (mean, 35 months). There were significant differences in volume of bone-graft among 3 groups (P lt; 0.05). There was no significant difference in total volume of bone-graft and Cage height among 3 groups (P gt; 0.05). The Oswestry disability index (ODI) and visual analogue scale (VAS) scores of low back pain and leg pain at last follow-up were significantly decreased when compared with preoperative scores in 3 groups (P lt; 0.05); but no significant difference was found among 3 groups (P gt; 0.05). The fusion rate was significantly higher in group B than in groups A and C, and in group A than in group C at 1 and 2 years after operation (P lt; 0.05). The change values of the intervertebral height were (2.2 ± 1.4), (0.8 ± 1.3), and (2.3 ± 1.6) mm respectively in groups A, B, and C; it was significantly lower in group B than in groups A and C (P lt; 0.05). The degree of vertebral slip at immediately after operation and last follow-up was significantly improved when compared with preoperative one in 3 groups (P lt; 0.05); the loss of vertebral slip in group B was significantly lower than that in groups A and C at last follow-up (P lt; 0.05). After operation, nail breaking occurred in 1 case (3.7%) of group C at 1 year, depinning in 1 case (3.8%) of group A at 2 years, and no nail breaking or depinning in group B. There was no significant difference in the incidence of internal fixation failure among 3 groups (χ2=3.950, P=0.604).
Conclusion
The application of bone-graft with middle volume (11 bone granules/cm3 on average) in internal fixation and posterior lumbar interbody fusion has a good imageology outcome, which can increase the fusion rate and decrease the loss of intervertebral height.
OBJECTIVE To testify the inductive osteogenesis of allogeneic bone matrix gelatin (BMG) in promoting intervertebral fusion. METHODS The gelatin sponge, allogeneic BMG, decalcified bone matrix (DBM) and alcohol conserved bone were implanted respectively into the intervertebral space of rabbit, whose intervertebral discs were removed before implantation. The intervertebral spaces were evaluated by X-ray and histological examination at 4, 8, and 12 weeks after operation. RESULTS No obvious immune rejection was observed. Amounts of new bone were formed in the intervertebral spaces at 4 and 8 weeks. And complete infusion of the intervertebral spaces were appeared at 12 weeks. CONCLUSION Allogeneic BMG can promote bone fusion of intervertebral spaces through osteoinduction, which suggests that allogeneic BMP is an ideal substitute for bone replacement.
ObjectiveTo comprehensively analyze the relationship between microRNAs and intervertebral disc degeneration at home and abroad.
MethodsThe literature about the relationship between microRNAs and intervertebral disc degeneration was reviewed and analyzed.
ResultsMicroRNA can lead to intervertebral disc degeneration by regulating the gene expression, thus influencing the cell's apoptosis and proliferation, increasing of the production of inflammatory mediator and protease, which play important roles in intervertebral disc degeneration.
ConclusionMicroRNA is a research focus in the field of intervertebral disc degeneration. Further research of the relationship between microRNAs and intervertebral disc degeneration will help to identify the pathogenesis of intervertebral disc degeneration and furnish the new ideal for the diagnosis and treatment of intervertebral disc degeneration.
Objective To explore changes in the height and width of the cervical intervertebral foramina of C6,7 before and after the C5,6 discetomy, the replacement or the anterior intervertebral fusion so as to provide the theoretical basis for the clinical practice. Methods Eleven fresh cervical spinal specimenswere obtained from young adult cadavers. The specimens of C5,6 were divided into the integrity group, the discectomy group, the artificial disc replacement group, and the intervertebral fusion group. The range of variety (ROV) of the C6,7 intervertebral foramen dimensions (height, width) before and after the loading tests (0.75, 1.50 Nm) were measured in the 4 groups. Results The C6,7 intervetebral foramen height and width increased significantly during flexion (Plt;0.01) but decreased significantly during extension (Plt;0.01). There was a significantdifference between the two test conditions in each of the 4 groups (Plt;0.01). However, in the two test conditions there was no significant difference in ROV of the C6,7 intervetebral foramen height and width during flexion and extension betweenthe integrity group, the discectomy, and the artificial disc replacement group(Pgt;0.05), but a significant difference in the above changes existed in the intervertebral fusion group when compared with the other 3 groups (Plt;0.05). In the same group and under the same conditions, the ROV of the C6,7 intervetebral foramen height and width was significantly different in the two test conditions (Plt;0.01). Conclusion The results have indicated thatartificial disc replacement can meet the requirements of the normal cervical vitodynamics. The adjacent inferior cervical intervetebral foramen increases during flexion but decreases during extension. The intervertebral fusion is probably one of the causes for the cervical degeneration or the accelerated degeneration and for the cervical spondylotic radiculopathy and the brachial plexus compression.
Objective To introduce the research advances of scaffold materials of intervertebral disc tissue engineering. Methods The recent original articlesabout the scaffolds in intervertebral disc tissue engineering were extensively reviewed. Results At present, agarose, alginate gel, collagentype Ⅰ, PLA, PGAare still major scaffold materials for intervertebral disc tissue engineering because of their good biocompatibility. Conclusion It is one of the popular studies on current intervertebral disc tissue engineering to explore the ideal scaffold materials.
Objective
To summarize the research progress of microRNA (miRNA) and its non-viral vector in intervertebral disc degeneration (IDD) and to investigate the potential of non-viral vector delivery of miRNA in clinical application.
Methods
The related literature about the role of miRNA in IDD and its non-viral delivery system was reviewed and analyzed.
Results
MiRNA can regulate the related gene expression level and further participate in the pathophysiologic process in degenerated intervertebral disc, miRNA delivered by various non-viral vectors has obtained an ideal effect in some diseases.
Conclusion
MiRNA plays a great role in the cellular and molecular mechanisms of IDD, as a safe and effective strategy for gene therapy, non-viral vector provides new possibilities for IDD treated with miRNA.
ObjectiveTo review the research progress of endogenous repair strategy (ERS) in intervertebral disc (IVD).MethodsThe domestic and foreign literature related to ERS in IVD in recent years was reviewed, and its characteristics, status, and prospect in the future were summarized.ResultsThe key of ERS in IVD is to improve the vitality of stem/progenitor cells in IVD or promote its migration from stem cell Niche to the tissue that need to repair. These stem/progenitor cells in IVD are derived from nucleus pulposus, annulus fibrosus, and cartilaginous endplate, showing similar biological characteristics to mesenchymal stem cells including the expression of the specific stem/progenitor cell surface markers and gene, and also the capacity of multiple differentiations potential. However, the development, senescence, and degeneration of IVD have consumed these stem/progenitor cells, and the harsh internal microenvironment further impair their biological characteristics, which leads to the failure of endogenous repair in IVD. At present, relevant research mainly focuses on improving the biological characteristics of endogenous stem/progenitor cells, directly supplementing endogenous stem/progenitor cells, biomaterials and small molecule compounds to stimulate the endogenous repair in IVD, so as to improve the effect of endogenous repair.ConclusionAt present, ERS has gotten some achievements in the treatment of IVD degeneration, but its related studies are still in the pre-clinical stage. So further studies regarding ERS should be carried out in the future, especially in vivo experiments and clinical transformation.
ObjectiveTo investigate the influence of ISOBAR TTL dynamic internal fixation system on degeneration of adjacent intervertebral disc by MRI measurement of lumbar nucleus pulposus volume in treating lumbar degenerative disease after operation.
MethodsBetween March 2010 and October 2011, 34 patients with lumbar intervertebral disc herniation (23 cases of paracentral type and 11 cases of lateral type) underwent operation with ISOBAR TTL dynamic internal fixation system for fixation of single segment, and the clinical data were analyzed retrospectively. There were 20 males and 14 females, aged 39-62 years (mean, 47.5 years). The disease duration was 6-18 months (mean, 14 months). Involved segments included L4, 5 in 21 cases and L5, S1 in 13 cases. The X-ray films and MRI images were taken at 6, 12, 18, 24, 36, and 48 months after surgery. Based on X-ray films, the height of intervertebral space was measured using angle bisectrix method. The nucleus pulposus volume was measured based on the MRI scan. The postoperative change of nucleus pulposus volume and intervertebral disc height were used to evaluate the influence of ISOBAR TTL system on degeneration of adjacent intervertebral disc nucleus pulposus.
ResultsThirty patients were followed up 48 months. The height of intervertebral space showed no significant difference between at pre-and post-operation (P>0.05). The nucleus pulposus volume increased after operation, showing no significant difference at 6, 12, and 18 months when compared with preoperative value (P>0.05), but significant difference was found at 24, 36, and 48 months when compared with preoperative value (P < 0.05). The height of nucleus pulposus increased after operation but the width was decreased; the values showed no significant difference at 6, 12, and 18 months when compared with preoperative ones, but showed significant difference at 24, 36, and 48 months when compared with preoperative ones (P < 0.05). The diameter of nucleus pulposus at 18, 24, 36, and 48 months after operation was significantly langer than that at preoperation (P < 0.05).
ConclusionISOBAR TTL dynamic internal fixation system can prevent or delay the degeneration of intervertebral discs.
Objective To review the research progress of the seed cells, scaffolds, growth factors, and the prospects for clinical application of the intervertebral disc regeneration. Methods The recent literature concerning the regeneration strategies and tissue engineering for treatment of degenerative intervertebral disc disease was extensively reviewed and summarized. Results Seed cells based on mesenchymal stem cells (MSCs) and multiple-designed biomimetic scaffolds are the hot topic in the field of intervertebral disc regeneration. It needs to be further investigated how to effectively combine the interactions of seed cells, scaffolds, and growth factors and to play their regulation function. Conclusion The biological regeneration of intervertebral disc would have a very broad prospects for clinical application in future.