BACKGROUND:Induced pluripotent stem cells research has become a hot topic nowadays, because it can avoid the immune rejection and ethical issues in stem cellresearch and have characteristics is similar to the embryonic stem cells.
OBJECTIVE:To review prospect and progress of induced pluripotent stem cells, and to find out some problems about the induced pluripotent stem cells in inducing method, efficiency, safety and application which need to be solved.
METHODS:Kjmed database was searched by the first author using key words of“induced pluripotent stem cells, efficiency, disease model, clinical application”in English to retrieve relevant articles published from January 2003 to June 2013. Literatures addressing induced pluripotent stem cells were included, and the repetitive researches were excluded.
RESULTS AND CONCLUSION:A total of 112 documents were retieved, and final y 32 articles were retained after deleting unrelated and repetitive ones. Induced pluripotent stem cells have very high application value and prospects in the somatic celltransplantation, tissue engineering, drug screening and establishment in vitro of disease models. But this technology is stil in the stage of research and exploration, and there are many technical problems that need to be solved.

BACKGROUND:Mesenchymal stem cells are capable of self-renew,a high degree of proliferation,with multi-differentiation potential,low immunogenicity and immunomodulatory properties.Both in vivo and in vitro it is able to regulate allogeneic immune response,to induce immune tolerance.In the solid organ transplantation it is playing an increasingly important role.OBJECTIVE:To summarize the research progress on the immunomodulatory mechanism and application of mesenchymal stem cells in solid organ transplantation.METHODS:An online search of Pubmed was undertaken by using the key words of "Mesenchymal Stem Cells,Mesenchymal Stem Cell Transplantation,Organ Transplantation,Transplantation Immunology,Immunologic Graft Enhancement,Graft vs.Host Disease" in Mesh to identify the relevant articles published in English from January 1994 to October 2009.At the same time,Wanfang database was screened to identify the relevant articles published between January 1994 and October 2009 with the key words of "Mesenchymal Stem Cells,Organ Transplantation,Transplantation Immunology" in Chinese.Inclusive criterion:The articles related to the immunomodulatory properties,transplantation immunology and application of mesenchymal stem calls in the solid organ transplantation were included.Exclusive criterion:The articles with repetitive research or Meta analysis were excluded.RESULTS AND CONCLUSION:Totally 200 relevant articles were selected and 86 of them met the inclusive criterion.Mesenchymal stem cells exhibit low immunogenicity and immunomodulatory properties,have an indispensable advantage about inducing graft tolerance and repairing tissue in solid organ transplantation.The mechanism of inducting immune tolerance may be related to soluble factors,regulatory T cells,tolerant dendritic cells,bone marrow chimerism,anti-inflammatory and tissue repair,dose and time of injecting MSCs.

Objective To discusse the mechanism and clinical significance of bradycardia -hypotension phenomenon which is caused by vagal reflex during and after the RFCA and present the experience of using appropriate measures to decrease the incidence of this situation. Methods The patients who were suffering from tachyarrhythmias and treated by RFCA were divided into two groups. The groups were as follows:148 patients who were not taken special measures in the early stage were selected in control group;1 540 patients who were taken measures to prevent vasovagal reflex were selected in observation group. Result During the RFCA, the incidence of bradycardia -hypotension phenomenon in control group was 13.5% (20/148), the incidence of bradycardia-hypotension phenomenon in observation group was 5.0%(77/1540) (<0.01) .Conclusions The incidence of bradycardia-hypotension phenomenon caused by vagal reflex during the RFCA is related to catheter irritation to the heart,pressure on the vessels and hypovolemia. The incidence of this phenomenon can be decreased obviously by some measures,such as non-restricted diet before RFCA,discretion rehydration during and after the RFCA and hemostasis with appropriate force after extubation. The key to rescue patients successfully are early detection and timely processing.

Objective:To observe immunological indexes,the quantity of cytokine expression and clinical curative effect of umbilical cord mesenchymal stem cells between before and after the treatment of systemic lupus erythematosus patients.Methods:Selected 10 cases of SLE,on the basis of glucocorticoid and immune inhibitor treatment,intravenous injection UC-MSC of cultivating proliferation within 6 generations.Before and after treatment of UC-MSC testing the relative quantity of cytokine of CTLA-4,IL-15,IL-2,CD86,IL-17c,Foxp3,TGF-β2 which were related of immunopathogenesis of SLE.Before and after treatment to determined SLE disease activity index (SLEDAI) score and detection of blood in the urine routine,liver and kidney function,24 hours urinary protein quantitative,immunoglobulin and complement levels.Results:After treatment the relative expression value of IL-15 and IL-2 was decreased,CTLA-4 was risen.There had no significant difference with the relative expression value of CD86,IL-17c,Foxp3,TGF-β2 in before and after treatment of UC-MSC.After treatment serum complement C3 and C4 level,serum albumin,were risen.24 hour proteinuria and SLEDAI were decreased.There was no serious adverse reaction occurred,no complications related to transplantation in 10 cases.Conclusion:UC-MSC can regulate the expression of cytokines of participate in the immune response in the patients with SLE.Treatment of SLE by UC-MSC can elevate serum albumin and C3 and C4 level,reduce the 24 hours urinary protein quantity,relife kidney damage,improve clinical symptoms;UC-MSC transplantation in patients with SLE have good security;UC-MSC transplantation may be a feasible method for the treatment of SLE.

Chimeric antigen receptor T (CAR-T) cell therapy is an emerging immunotherapy that has allowed for major breakthroughs in the treatment of hematological neoplasms. However, little progress has been made in the treatment of solid tumors, primarily due to the difficulty in homing to tumor tissues by CAR-T cells during treatment. The complex tumor microenvironment and the barrier function of tumor tissues prevent CAR-T cells from contacting tumor cells, thereby preventing them from exerting their antitumor ac-tivity. This review article summarizes not only the progress made in the study of homing disorders of CAR-T cells in the treatment of solid tumors but also the current methods to overcome these disorders.

Gastric cancer (GC) is one of the most resistant malignancy to several treatment strategies. In recent years, the morbidity and mortality of GC has stayed high. Surgical resection remains the main treatment option for GC at present. Although chemotherapy, radiotherapy, immunotherapy, and traditional Chinese medicine are used as adjuvant therapies after surgery, the prognosis and five-year survival rate are still low. Currently, there is no effective method for early diagnosis of GC and thus most patients are diagnosed only when the advanced symptoms appear. Exosomes contain and transfer DNA, RNA, proteins, lipids, and other biological macromole-cules. Several studies have found that exosomes are involved in tumor processes including cell proliferation and metastasis. In particu-lar, the abundant biological macromolecules present in the exosomes reflect the progress of tumor development thereby enabling them as non-invasive diagnostic markers. This provides a new idea for diagnosing GC in early stages. In this review, the contribution of exosomes to GC metastasis and the applications of exosomes in early GC diagnosis are briefly summarized.

嵌合抗原受体T（chimeric antigen receptor T， CAR-T）细胞是一种通过基因工程表达受体的T细胞，能够识别特定的抗 原，是目前最具潜力的靶向肿瘤治疗方法。然而，作为抗癌免疫系统中主要效应细胞之一的CD8+T细胞在肿瘤中发挥作用时， 通 常处于耗竭状态，而这种功能缺陷的CD8+T细胞是杀伤肿瘤的障碍。肿瘤微环境（tumor microenvironment，TME）中存在许多抑 制性因素，例如耗竭性T细胞表面高表达的抑制性受体、免疫抑制细胞群、抑制性因子、转录因素、代谢因素等都对T细胞的分化 及耗竭有重要影响。当然， CAR的结构和共刺激域也对CAR-T细胞整体功能发挥着重要作用。本文着重总结近年有关CD8+T 细胞耗竭的机制及改善策略的研究进展，为增强CAR-T细胞的抗肿瘤效应提供了潜在思路。