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Objective To probe the immunological traits of mesenchymal stem cells derived from umbilical cord Wharton's jelly (WJMSCs). Methods The diced Wharton's jelly which was from healthy fullterm birth human umbilical cord was cultured. The mesenchymal stem cells were identified with mesenchymal stem cells markers expression by flow cytometry and multiple differentiation ability. The expression of MHC- Ⅰ / Ⅱ, costimulatory molecules (CD40, CD80 and CD86) was detected with flow cytomctry, immunocytochemistry, and RT-PCR. The expression of immune inhibitors like HLA-G, IDO, and PGE2 was detected by immunocytochemistry and RT-PCR. The expression of immune-related molecules as IL-10, TGF-β, FGF and VEGF was detected with antibody microarray and western blot. Further more, to clarify the in vivo immune reaction of hWJMSCs, we fabricated the hWJMSC-scaffold constructs and implanted them into the rabbit backs. The lymphocyte infiltration and implanted cell survival observed with immunofluorescence. Results After culturinge of diced Wharton's jelly tissue, we obtained spindle-shaped cells. With differentiation medium, the cells can differentiate into osteoblasts, chongdrocytes, adipose cells and schwann cells. Expression of MHC, costimulatory molecules, and a series of immune suppressive-related molecules was found. Immune inhibitors as HLA-G, 1DO, PGE2, and immune suppressive related molecules as HGF, VEGF, TGFand IL-10 were positively expressed. But the cells did not express MHC-Ⅱ. No immune rejection was observed in vivo after implantation of hWJMSC-scaffold constructs. Conclusion It can be concluded that hWJMSCs have very low immunogenicity, which means the cells have potential to induce immune tolerance.The hWJMSCs do not provoke immune rejection in vivo.
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[Objective]To investigate surgical therapeutic methods of recurrent lumbar disc herniation(RLDH).[Method]From December 1996 to December 2003,a retrospective analysis on surgical treatment of 74 cases of RLDH was made and those cases acquired 1～5 years follow-up.There were 41 males,33 females aging from 21~53 years(mean,37.2 years),case history was 6~192 months from primary surgery to disc reprolapse(mean,37 months).Among primary surgery,9 cases were total laminectomy,23 cases were hemilaminectomy,31 cases were windowing,11 cases were microdiscectomy with diskoscope.Re-surgery:5 cases treated with lumbar disc excision,45 cases treated with posterior lumbar interbody fusion(PLIF)technich,23 cases treated with transforminal lumbar interbody fusion(TLIF)technich.[Result]No death case occurred during peri-operation.Various complications were found in 18 cases which recovered by symptomatic treatment.Cases with lumbar disc excision left bed in 3 weeks with the help of lumbar back brace and cases with fusion surgery left bed in 3～5 d after surgery.Oswestry score improved from(52.32?9.17)pre-operatively to(20.33?5.72)in average 18 months follow-up.Totally 73.5% cases had satisfactory surgical results.[Conclusion]Cases with RLDH can adopt propotional surgical methods,thoroughly decompression and gain satisfactory therapeutic effect on bases of imageology,clinical manifestation and surgery history.
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Objective To summarize clinical manifestations and diagnostic criteria of ischemic reperfusion (IR) injury to the spinal cord. Method The clinical manifestations and management of 15 cases of spinal cord IR injury after operation during 2000 to 2005 were retrospectively analyzed. Result All the patients with spinal cord IR injury presented progressive ascending motor and sensory functional impairment beginning from lower extremities 3h post operation, and they were all treated immediately with methylprednisolone and neurotrophy drugs to restore spinal cord function. However, mechanical compression with organic lesion should be ruled out to establish the diagnosis of spinal cord IR injury in the retrospective analysis. Different stages of spinal cord IR injury occurred in these 15 cases. Through symptomatic treatment, 8 patients recovered completely; the clinical symptoms were basically improved in 4 cases who could lead a normal life; in 3 patients clinical symptoms were improved but not satisfactory. Conclusion Though spinal cord IR injury seldom occurs in the clinic, its damage is disastrous. Proper management is critical to save patients from poor life quality.
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Objective To investigate the bionomics of mesenchymal stem cells (MSCs) derived from Wharton's jelly of human umbilical cord. Methods Umbilical arteries, vein and umbilical cord tunica externa were removed, and the remaining tissue (Wharton's jelly) was harvested. To gather MSCs, the umbilical cord was cut into small fragments and digested with 0.075% type Ⅰ collagenase, or the small fragments were cultured with DMEM. The cells derived from Wharton's jelly of umbilical cord were serially subcultivated, the growth curve was drawn, and the identification of living cells was made for studying the cell growth kinetics. The surface antigens were detected with flow cytometry, the cartilage markers were detected by histochemistry and immunohistochemistry, and the expressions of Sox-9 and Col-2A1 mRNA were analyzed by RT-PCR. Results The confluence time of primary culture cells was 3-5d in cells harvested with enzyme digestion, and 10-15d in cells harvested with micro mass. The results of flow cytometry showed that the MSCs derived from umbilical cord expressed CD44 and CD105; the expression of HLA-ABC was positive, while HLA-DPDQDR was negative. There was no significant change on the immunophenotype of umbilical cord MSCs after cryopreservation and thawing. The findings of histochemistry and immunohistochemistry showed that the expression of chondrocyte markers in Wharton's jelly MSCs was weakly positive. The results of RT-PCR showed the chondrocyte markers Sox-9 and Col-2A1 were positively expressed in Wharton's jelly MSCs. Conclusion The MSCs derived from Wharton jelly of human umbilical cord do not differentiate into hematopoietic cells, may express the chondrocyte markers (they are suggested to have characteristics of pre-chondrocytes), and is expected to be a new type of stem cells of tissue engineering cartilage.