Objective To compare the molecular phenotype of human intervertebral disc cells and articular chondrocytes and to analyze whether hBMSCs can differentiate into both chondrocytes and nucleus pulposus cells after combined induction of TGF-β3 and BMP-7 in vitro. Methods The cells with the characteristics of hBMSCs were isolated from marrow aspirates of the volunteer donors’ il iac crest. Human bone marrow was removed and fractionated, and adherent cell cultures were establ ished. The 4th passage cells were then translated into an aggregate culture system in a serum-free medium. The pellet cultures of hBMSCs were divided into four groups: 10 ng/mL TGF-β3 group (group A), 200 ng/mL BMP-7 group (group B), combination group of TGF-β3 and BMP-7 (group C) and blank group as the control (group D). Histological observation, RT-PCR and RQ-PCR were appl ied to measure the expressions of collagen type I, II, X, aggrecan and SOX9 on the 4th and 21st day after cell induction, respectively. Results As was shown by histological observation, the induced cells expressed the feature of chondrocytes in morphology and ECM in groups A and C on the 21st day after the culture. And the collagen type II was positive after staining in groups A and C. The cell morphology of the induced cells in groups B and C had no obviouly changed. PCR detection showed that the expressions of SOX9, aggrecan, collagen type I, II in groups A and C at 21st day were more increased than those at 4th day (P lt; 0.05). The only expressions of collagen type I in groups B and D at 21st day were more increased than those at 4th day (P lt; 0.05). The expressions of collagen type X only was positive in group A. Conclusion Combination of TGF-β3 and BMP-7 can make the differentiated cells from hBMSCs much closer to intervertebral disc cells, so it perhaps could provide seed cells for intervertebral disc tissue engineering.
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.
【Abstract】 Objective To investigate the effects on forming of hypertrophic scar after BMSCs infected with adenovirus carrying TGF-β3c2s2 were transplanted into the wound of animal scar model. Methods The third passage of rabbit’ s BMSCs were infected with 150 mutiple infection, and were cultured 24 hours. The concentration of the BMSCs infected with recombinant adenovirus containing the TGF-β3c2s2 gene was 1×105cell/mL. The purified and evaporated recombinant adenovirus grains containing the TGF-β3c2s2 gene were diluted by DMEM/F12 (without FBS) to 1×108 pfu/mL. The animal scar model of the standard Japanese big ear rabbit was establ ished. Eighty wounds were generated on the gastroside of ear and were randomized to 4 groups in each rabbit, which were divided into 3 control groups (A: control, B: Ad-TGF-β3c2s2, C: BMSCs) and 1 experimental group (D: BMSCs/Ad-TGF-β3c2s2). Then the wounds were tranplanted with cells. On 45 days and 90 days after wounded, thicknessand hardness of scars were measured with color ultrasound diagnostic unit and especial measurement for skin and scar hardness. On 21, 45 and 90 days, three specimens were harvested respectively for further histological study. Results The wound of groups A, B, C gradually formed the different degree scars after epithel ial ization. The hyperplasty of scars reached peak on 45 days after wounded and lasted about 90 days. There was no prominent scar formed in group D during the whole observed procedure. Thickness and hardness of scar of group D and group E were approximate on 45 days and 90 days. Thickness and hardness of scar of groups A, B and C were lower than those of group D (P lt; 0.01), and group B showed more lower than group A and group C (P lt; 0.01). Disorder structure and overlapping arrangement, enlargement collagen fibers were showed in the HE histological sections of the scars of groups A, C. The structure of the scars of groups B, C were similar to Group E. The constitutionsof groups A, B, C, D on 90 days resembled to each one on 45 days. In section of immunohistochemistry after wounded on21 days and 45 days, positive expressions of BrdU in nucleus of Groups C, D were observed. Negative expressions of BrdU in Groups A, B, E were showed. Conclusion BMSCs with Ad-TGF-β3c2s2 gene transplanted into wound could inhibit the forming of hypertrophic scar.