Clinical efficacy of Atezolizumab and Bevacizumab in the treatment of initially borderline resectable advanced liver cancer / 中华消化外科杂志

Conversion therapy has become the core in the treatment of borderline resectable or unresectable liver cancer, which provides resectable opportunities for more advanced liver cancer patients. In accordance with the first-choice treatment regimen recommended by the guidelines, the authors reported a successful case of Atezolizumab and Bevacizumab (T+A regimen) conversion therapy. The patient with initially borderline resectable advanced liver cancer was performed liver segment resection sucessfully after conversion therapy, and non-tumor recurrence was observed at postoperative 9 months. Postoperative pathological examination showed combined hepatocellular-cholangiocarcinoma, which also indicated the important value of T+A regimen in the conversion therapy of combined hepatocellular-cholangiocarcinoma.

Decellularized matrix of human fatty liver used for three-dimensional culture of hepatocellular carcinoma cells / 南方医科大学学报

OBJECTIVE@#To construct a decellularized matrix of human fatty liver as the scaffold for three-dimensional (3D) culture of hepatocarcinoma cells.@*METHODS@#Human fatty liver decellularized matrix (hFLM) was prepared by repeated freezingthawing, perfusion with gradient SDS and 1% Triton X-100 through the portal vein and hepatic artery, and repeated agitation with Triton X-100. HepG2 cells were cultured in the prepared hFLM, and the cell survival, morphology, proliferation and cellular expressions of the adhesion molecules were detected.@*RESULTS@#The decellularization procedure shortened the time for scaffold preparation and preserved the 3D ultrastructure and the composition of the extracellular matrix. HepG2 cells cultured in hFLM scaffold maintained proliferation for up to 15 days and showed a growth pattern with a long lag phase and a slow growth rate, which was similar to the growth pattern . The cultured HepG2 exhibited a low expression of E-cadherin and a high expression of vimentin, which was consistent with the xenograft but opposite to 2D cultured cells. However, the lack of adequate nutrient transport in this hepatocarcinoma cell model led to a slowdown of cell proliferation in the later stage. The PCNA index of HepG2 cells cultured in hFLM was lowered by 29.3% on day 12 as compared with that on day 6.@*CONCLUSIONS@#We established a new protocol for preparing hFLM and confirmed the feasibility of constructing hepatocarcinoma cell models using the hFLM scaffold.

Development of magnetic spiderman to optimize the procedures of repairment of donor liver from organ donation / 器官移植

Objective To develop a pulling device using magnetic positioning to optimize the procedures of repairment of donor liver from organ donation . Methods The pig liver specimens were used to measure the pull force of repairment of donor liver, magnetic spiderman was developed based on the measurement results. The magnetic spiderman was applied to simulate the repairment of donor liver from organ donation on the pig liver specimens. The effectiveness of magnetic spiderman was also evaluated. Results The pulling force was required all less than 2 N during the repairment of donor liver. The magnetic spiderman was successfully manufactured. The magnets of magnetic spiderman could generate 3 N magnetic forces with paramagnetic basin of hepatic repairment. The self-retraction pull wire of the magnetic spiderman could provide 2.5 N pulling forces. The magnetic spiderman was successfully applied to the simulated experiment of repairment of donor liver from organ donation in 6 cases. The operation time was (54±5) min. No clip slippage,displacement and slippage of the base occurred during the operation. With the cooperation of multiple magnetic spidermen,the remaining surgical procedures were performed by one single surgeon except for the vascular ligation. Conclusions The magnetic spiderman has small volume and implements flexible positioning, can perform pulling operation and nottake up operational space. It can effectively optimize the procedures of repairment of donor liver from organ donation and reduce the quantity of surgeons.

Strategies to choose scaffold materials for tissue engineering / 生物工程学报

Current therapies of organ failure or a wide range of tissue defect are often not ideal. Transplantation is the only effective way for long time survival. But it is hard to meet huge patients demands because of donor shortage, immune rejection and other problems. Tissue engineering could be a potential option. Choosing a suitable scaffold material is an essential part of it. According to different sources, tissue engineering scaffold materials could be divided into three types which are natural and its modified materials, artificial and composite ones. The purpose of tissue engineering scaffold is to repair the tissues or organs damage, so could reach the ideal recovery in its function and structure aspect. Therefore, tissue engineering scaffold should even be as close as much to the original tissue or organs in function and structure. We call it "organic scaffold" and this strategy might be the drastic perfect substitute for the tissues or organs in concern. Optimized organization with each kind scaffold materials could make up for biomimetic structure and function of the tissue or organs. Scaffold material surface modification, optimized preparation procedure and cytosine sustained-release microsphere addition should be considered together. This strategy is expected to open new perspectives for tissue engineering. Multidisciplinary approach including material science, molecular biology, and engineering might find the most ideal tissue engineering scaffold. Using the strategy of drawing on each other strength and optimized organization with each kind scaffold material to prepare a multifunctional biomimetic tissue engineering scaffold might be a good method for choosing tissue engineering scaffold materials. Our research group had differentiated bone marrow mesenchymal stem cells into bile canaliculi like cells. We prepared poly(L-lactic acid)/poly(ε-caprolactone) biliary stent. The scaffold's internal played a part in the long-term release of cytokines which mixed with sustained-release nano-microsphere containing growth factors. What's more, the stent internal surface coated with glue/collagen matrix mixing layer containing bFGF and EGF so could supplying the early release of the two cytokines. Finally, combining the poly(L-lactic acid)/poly(ε-caprolactone) biliary stent with the induced cells was the last step for preparing tissue-engineered bile duct. This literature reviewed a variety of the existing tissue engineering scaffold materials and briefly introduced the impact factors on the characteristics of tissue engineering scaffold materials such as preparation procedure, surface modification of scaffold, and so on. We explored the choosing strategy of desired tissue engineering scaffold materials.

Core Issues of Mechanical Perfusion in Preservation and Repairing of Donor Liver after Cardiac Death / 生物医学工程学杂志

The quality of a donor liver after cardiac death is closely associated with energy metabolism during preservation. Ex vivo mechanical perfusion has broad application prospects because this technique can help energy metabolism and repair ischemia injury of donors' livers. Some core issues are presented in this review in order to provide references for propelling secure application of liver transplantation based on donation after cardiac death.

Preparation of a decellularized scaffold derived from human liver tissue / 南方医科大学学报

<p><b>OBJECTIVE</b>To develop a method for preparing a decellularized scaffold based on human liver tissue.</p><p><b>METHODS</b>A surgical specimen of the left lateral lobe of the liver was obtained from a patients with hepatic hemangioma. The decellularization process was performed by repeated freezing-thawing, sequential perfusion with 0.01% SDS, 0.1% SDS and 1% Triton X-100 through the portal vein, and sterilization with peracetic acid. L-02 cells were then engrafted onto the decellularized liver scaffold.</p><p><b>RESULTS</b>HE staining, DAPI staining and scanning electron microscopy all verified the absence of residual cellular components in the decellularized scaffold. The residual DNA content in the decellularized scaffolds was 25.3∓14.6 ng/mg (dry weight), which was less than 1% of the total DNA content in a fresh human liver. Immunohistochemistry demonstrated that type I and IV collagens, fibronectin and elastin were all retained in the scaffold. The engrafted L-02 cells survived well on the scaffold with active proliferation and expressed albumin and G6pc.</p><p><b>CONCLUSION</b>It is feasible to prepare decellularized scaffolds using surgical specimens of human liver, which can be a new approach to constructing a tissue-engineered liver for clinical purposes.</p>

Optimization of the protocols for in vitro culture and induction of hepatic differentiation of rat mesenchymal stem cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To optimize the protocols for isolation, in vitro culture, identification and induction of hepatic differentiation of rat bone marrow mesenchymal stem cells (BMSCs).</p><p><b>METHODS</b>Rat BMSCs were separated and purified by differential adherent culture for 1.5 h with the first medium change at 12 h. The surface markers of BMSCs were detected by flow cytometry. The cells were induced to differentiate into adipogenic, osteogenic, and chondrogenesis lineages. A 3-step protocol including sequential addition of growth factors, cytokines and hormones was used to induce the BMSCs to differentiate into hepatocyte-like cells.</p><p><b>RESULTS</b>The cells isolated using this protocol were positive for CD29, CD44, and CD90 and negative for CD29 and CD45. The adipogenic, osteogenic, and chondrogenic differentiation of the BMSCs were verified by Oil red, Alizarin red, and toluidine blue staining. The BMSCs induced with the 3-step protocol differentiated into hepatic-like cells that expressed hepatocyte-specific proteins (ALB and AFP) and genes.</p><p><b>CONCLUSION</b>The optimized protocol allows simple and efficient isolation of highly purified populations of BMSCs, which can be induced into hepatic lineages in specific microenvironment.</p>

Optimization of the method for isolating and culturing rat mesenchymal stem cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To optimize the protocols for isolation and culture of mesenchymal stem cells from rat bone marrow (BMSCs).</p><p><b>METHODS</b>BMSCs were isolated by adherence to plastic with frequent medium change and reduced trypsinization time. The cell growth curves were drawn and the surface markers of BMSCs were detected by flow cytometry. The cells were induced to differentiate into osteogenic, adipogenic, hepatic and cholic lineages.</p><p><b>RESULTS</b>The cells isolated using this method were positive for CD29, CD44, and CD90 and negative for the hematopoietic surface markers CD45. The osteogenic and adipogenic differentiation of the BMSCs was verified by alkaline phosphatase staining, Alizarin red staining and Oil red staining. The cell subcultures up to passage 10 maintained capacities of differentiation into osteogenic and adipogenic lineages. The BMSCs induced with sequential addition of growth factors, cytokines and hormones differentiated into cells expressing hepatocyte- and cholangiocyte-specific markers.</p><p><b>CONCLUSION</b>The optimized method allows efficient isolation of homogenous populations of MSCs from rat bone marrow, which can be induced into multiple cell lineages.</p>

Vascularization for tissue engineering organs:research progress and application prospect / 中国组织工程研究

BACKGROUND:An efficient blood vessel system has a decisive effect on the survival and function expression of cells in three-dimensional tissues. Therefore it has been a hot research field in tissue engineering to find an appropriate vascularization strategy. OBJECTIVE:To summarize and discuss the theory and research progress in vascularization strategies. METHODS:Literature search was performed in PubMed database for English literatures published from 2003 to 2013. The key words are“tissue engineering, vascularization, endothelial cell, scaffold”in English. Then, the papers were further analyzed and reviewed in line with the theme. RESULTS AND CONCLUSION:A total of 124 papers were searched. At last, 41 papers were selected according to the titles and objectives. Vascularization is the focus and pressing issue in tissue engineering field. There are many vascularization strategies, such as growth factor delivery, cellco-culture, dynamic-culture by bioreactor, scaffolds or decellularized scaffolds. But none of them is recognized as an effective strategy to achieve functional anastomosis with the host and sustain grafts survival for a long time in vivo. It wil be a big breakthrough in the future to co-culture pluripotent stem cells with other stem cells, combine with growth factors and optimize culture conditions for the differentiation in vivo.