Objective To review the current research status and clinical application progress of extracellular matrix (ECM) material in tissue engineering. Methods The literature about the latest progress in the preparation, biocompatibility, mechanical property, degradability, and clinical application of ECM material was extensively reviewed. Results The improvement of the ECM preparation method and thorough understanding of the immunological properties have laid the foundation for the repair and reconstruction of the tissue. Moreover, a series of animal studies also confirm that the feasibility and effectiveness of the ECM such as small intestinal submucosa, bladder ECM grift, and acellular dermis which have been applied to the repair and reconstruction of the urethra, bladder, arteries, and skin tissue. It shows a wide prospect of clinical application in the future. Conclusion ECM material is a good bio-derived scaffold, which is expected to become an important source of alternative materials for the repair and reconstruction of the tissue.
【Abstract】 Objective To review the progress and cl inical appl ication of cellular therapy for stress urinaryincontinence (SUI). Methods The l iterature about cellular therapy of SUI was extensively reviewed. Results Becauseof having no or poor regeneration capacity, the cl inical application of chondrocytes and myoblasts were l imited. Based on the rapid progress in stem cell biology, an increasing number of animal experiments and cl inical trials about cellular therapy of SUI have been reported with encouraging results. All these show that cellular therapy has great potential in cl inical application. Stem cells are considered as ideal seeded-cells for treatment of SUI. Conclusion Cellular therapy, especially stem cells, provides a novel approach for treatment of SUI, but the mechanism needs further study.
Objective To sum up the common mode in urinary diversion after radical cystectomy. Methods The recent original articles about the common mode in urinary diversion after radical cystectomy were extensively reviewed. Results Urinary diversion includes no continent ureterocutaneostomy, continent ureterocutaneostomy and orthotopic neobladder. Ileal conduit, an ideal procedure of urinary diversion, has been widely used in patients after radical cystectomy and it is uncertain whether the health related quality of life in patients undergoing orthotopic ileal neobladder is superior to those undergoing ileal conduit. A series of basic researches of tissue engineering show a wide prospect of clinical application in the future. Conclusion Intestinal segment will remain the main material for urinary diversion and bladder reconstruction in a long time. Tissue engineering materials may be ideal for the substitution of bladder, and tissue engineering becomes the ultimate approach to solve the problem of missing bladder.
ObjectiveTo prepare a composite scaffold using bladder acellular matrix (BACM) and polyurethane (PU) for bladder repair and regeneration, and to evaluate its mechanical properties and biocompatibility. MethodsFresh bladder tissues were obtained from New Zealand rabbits and then treated with 1%SDS and 1%Triton X-100 to obtain BACM. The BACM was combined with PU to fabricate PU-BACM composite scaffold. The tensile strength and elongation at break of BACM and PU-BACM scaffolds were tested. Scaffolds and extracts of scaffolds were prepared to evaluate the biocompatibility. For cell-proliferation analysis, cell counting kit 8 method was used at 1, 3, 5, and 7 days after co-culture of human bladder smooth muscle cell (HBSMC) and scaffolds. The cell cycle was tested by flow cytometry after HBSMC co-cultured with extracts of scaffolds and DMEM culture medium (control group) for 24 hours. Finally, 12 New Zealand rabbits were used to establish the model of bladder repair and regeneration. Incision of 5 mm was made on the bladder, and PU-BACM scaffold was sutured with the incision. The rabbits were sacrificed at 10, 20, 40, and 60 days after surgery to observe the inflammatory cell infiltration, new tissues formation, and regeneration of epithelium by HE staining. ResultsThe tensile strength of BACM and PU-BACM composite scaffold was (5.78 ± 0.85) N and (11.88 ± 3.21) N, and elongation at break was 14.46%±3.21% and 23.14%±1.32% respectively, all showing significant diffeence (t=3.182, P=0.034；t=4.332, P=0.012). The cell-proliferation rates of controls, PU, BACM, and PU-BACM were 36.78%±1.21%, 30.49%±0.89%, 18.92%±0.84%, and 22.42%±1.55%, it was significantly higher in PU-BACM than BACM (P<0.05). In the bladder repair and regeneration experiment, inflammatory cell infiltration was observed at 10 days after operation, and reduced at 20 days after implantation. In the meanwhile, the degradation of scaffolds was observed in vivo. The regeneration of epithelium could be observed after 40 days of implantation. At 60 days after implantation, in situ bladder tissue formed. ConclusionPU-BACM composite scaffold has higher mechanical properties and better biocompatibility than BACM scaffold. PU-BACM composite scaffold will not lead to strong immune response, and new bladder tissue can form in the in vivo rabbit bladder repair experiment. These results can provide research basis and theoretical data for further study.
Objective To observe whether umbilical cord mesenchymal stem cells (UCMSCs) can differentiate into the smooth muscle cells (SMCs) induced by bladder SMCs (BSMCs) conditioned medium so as to seek an alternative seed cells for the repair and reconstruction of the urology system. Methods UCMSCs and BSMCs were harvested from umbilical cord of full-term births and bladder tissues which were obtained from patients who underwent a radical cystectomy. BSMCs conditioned medium was prepared by mixing supernatant of BSMCs at passages 1-5 with complete medium at ratio of 1 ∶ 1. UCMSCs at passage 3 were cultured with BSMCs conditioned medium (induced group, group A) and complete medium (control group, group B), respectively; simple BSMCs served as positive control group (group C). The morphological changes of co-cultured UCMSCs were observed by inverted phase microscope, the expressions of α-smooth muscle actin (α-SMA), Calponin, and smooth muscle myosin heavy chain (SM-MHC) of UCMSCs were tested by immunofluorescence staining and Western blot at 7 and 14 days. Results The morphology of UCMSCs in group A started to change from a polygonal and short spindle shape to a large and spindle shape after co-culture, which was similar to BSMCs morphology; but the morphology of UCMSCs did not change obviously in group B. Immunofluorescence staining showed that the expressions of α-SMA, Calponin, and SM-MHC were positive in group C. At 7 days, the expression of α-SMA could be observed in groups A and B; at 14 days, the positive expression of α-SMA increased gradually in group A, but it did not increase in group B. At 7 days, a positive expression of Calponin could be observed in group A, and positive expression increased obviously at 14 days; the expression of Calponin could not be observed at 7 and 14 days in group B. However, the expression of SM-MHC could not be observed in groups A and B. The results of Western blot showed the expressions of α-SMA, Calponin, and SM-MHC protein were consistent with the results of immunofluorescence staining. Conclusion UCMSCs have the potential of differentiation into SMCs and may be a potential seed cells for bladder tissue engineering.