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Tumor tissue is composed of tumor cells and tumor stroma. Tumor stroma contains various immune cells and non-immune stromal cells, forming a complex tumor microenvironment which plays pivotal roles in regulating tumor growth. Recent successes in immunotherapies against tumors, including immune checkpoint inhibitors, have further raised interests in the immune microenvironment of liver carcinoma. The immune microenvironment of tumors is formed because of interactions among tumor cells, immune cells and non-immune stromal cells, including fibroblasts and endothelial cells. Different patterns of immune microenvironment are observed among different tumor subtypes, and their clinicopathological significance and intertumor/intratumor heterogeneity are being intensively studied. Here, we review the immune microenvironment of hepatocellular carcinoma, intrahepatic cholangiocarcinoma and liver metastasis of colorectal adenocarcinoma, focusing on its histopathological appearance, clinicopathological significance, and relationship with histological and molecular classifications. Understanding the comprehensive histopathological picture of a tumor immune microenvironment, in addition to molecular and genetic approaches, will further potentiate the effort for precision medicine in the era of tumor-targeting immunotherapy. 相似文献
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Jose M. Morales Jose Angel Martinez-Flores Manuel Serrano Maria José Castro Francisco Javier Alfaro Florencio García Miguel Angel Martínez Amado Andrés Esther González Manuel Praga Estela Paz-Artal Antonio Serrano 《Journal of the American Society of Nephrology : JASN》2015,26(3):735-745
In the current immunosuppressive therapy era, vessel thrombosis is the most common cause of early graft loss after renal transplantation. The prevalence of IgA anti–β2-glycoprotein I antibodies (IgA-aB2GPI-ab) in patients on dialysis is elevated (>30%), and these antibodies correlate with mortality and cardiovascular morbidity. To evaluate the effect of IgA-aB2GPI-ab in patients with transplants, we followed all patients transplanted from 2000 to 2002 in the Hospital 12 de Octubre prospectively for 10 years. Presence of IgA-aB2GPI-ab in pretransplant serum was examined retrospectively. Of 269 patients, 89 patients were positive for IgA-aB2GPI-ab (33%; group 1), and the remaining patients were negative (67%; group 2). Graft loss at 6 months post-transplant was significantly higher in group 1 (10 of 89 versus 3 of 180 patients in group 2; P=0.002). The most frequent cause of graft loss was thrombosis of the vessels, which was observed only in group 1 (8 of 10 versus 0 of 3 patients in group 2; P=0.04). Multivariate analysis showed that the presence of IgA-aB2GPI-ab was an independent risk factor for early graft loss (P=0.04) and delayed graft function (P=0.04). There were no significant differences regarding patient survival between the two groups. Graft survival was similar in both groups after 6 months. In conclusion, patients with pretransplant IgA-aB2GPI-ab have a high risk of early graft loss caused by thrombosis and a high risk of delayed graft function. Therefore, pretransplant IgA-aB2GPI-ab may have a detrimental effect on early clinical outcomes after renal transplantation. 相似文献
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Hsiao-Hsuan Kuo Ran Fan Nina Dvorina Andres Chiesa-Vottero William M. Baldwin III 《Journal of the American Society of Nephrology : JASN》2015,26(4):855-863
Antibody-mediated rejection is a major complication in renal transplantation. The pathologic manifestations of acute antibody-mediated rejection that has progressed to functional impairment of a renal transplant have been defined in clinical biopsy specimens. However, the initial stages of the process are difficult to resolve with the unavoidable variables of clinical studies. We devised a model of renal transplantation to elucidate the initial stages of humoral rejection. Kidneys were orthotopically allografted to immunodeficient mice. After perioperative inflammation subsided, donor-specific alloantibodies were passively transferred to the recipient. Within 1 hour after a single transfer of antibodies, C4d was deposited diffusely on capillaries, and von Willebrand factor released from endothelial cells coated intravascular platelet aggregates. Platelet-transported inflammatory mediators platelet factor 4 and serotonin accumulated in the graft at 100- to 1000-fold higher concentrations compared with other platelet-transported chemokines. Activated platelets that expressed P-selectin attached to vascular endothelium and macrophages. These intragraft inflammatory changes were accompanied by evidence of acute endothelial injury. Repeated transfers of alloantibodies over 1 week sustained high levels of platelet factor 4 and serotonin. Platelet depletion decreased platelet mediators and altered the accumulation of macrophages. These data indicate that platelets augment early inflammation in response to donor-specific antibodies and that platelet-derived mediators may be markers of evolving alloantibody responses. 相似文献
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Thomas W. McDade Alexander V. Georgiev Christopher W. Kuzawa 《Evolution, Medicine, and Public Health》2016,2016(1):1-16
Immune defenses provide resistance against infectious disease that is critical to survival. But immune defenses are costly, and limited resources allocated to immunity are not available for other physiological or developmental processes. We propose a framework for explaining variation in patterns of investment in two important subsystems of anti-pathogen defense: innate (non-specific) and acquired (specific) immunity. The developmental costs of acquired immunity are high, but the costs of maintenance and activation are relatively low. Innate immunity imposes lower upfront developmental costs, but higher operating costs. Innate defenses are mobilized quickly and are effective against novel pathogens. Acquired responses are less effective against novel exposures, but more effective against secondary exposures due to immunological memory. Based on their distinct profiles of costs and effectiveness, we propose that the balance of investment in innate versus acquired immunity is variable, and that this balance is optimized in response to local ecological conditions early in development. Nutritional abundance, high pathogen exposure and low signals of extrinsic mortality risk during sensitive periods of immune development should all favor relatively higher levels of investment in acquired immunity. Undernutrition, low pathogen exposure, and high mortality risk should favor innate immune defenses. The hypothesis provides a framework for organizing prior empirical research on the impact of developmental environments on innate and acquired immunity, and suggests promising directions for future research in human ecological immunology. 相似文献
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以曼氏血吸虫的虫卵和成虫免疫家兔后所产生的特异性抗体,可用以日本血吸虫虫卵、尾蚴和成虫为抗原分别进行的COP,CHR和ELACIEP测出,表明两种人体血吸虫存有显著的交叉抗原成分。应用此种血清交叉反应性,以检测抗异种人体血吸虫的抗体,似有效而可取的,可用以辅助诊断援外回国人员是否感染国外人体血吸虫病。 相似文献
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抗原激活红细胞和白细胞免疫反应主干道的实验研究 总被引:2,自引:0,他引:2
目的测定抗原对红细胞和白细胞免疫反应主干道的作用。方法癌细胞(5×106/ml)和(或)卡介苗(0·1mg)或酵母菌(5×108/ml)加到全血细胞悬液0·2ml(或白细胞0·2ml)和枸橼酸抗凝的新鲜血浆0·3ml(或生理盐水0·3ml)37℃温育1h,采用免疫酶联法检测IL-8水平。分组:①抗原(癌细胞或酵母菌或卡介苗)0·2ml加入全血细胞悬液0·2ml和血浆0·3ml;②生理盐水0·2ml加入全血细胞悬液0·2ml和血浆0·3ml;③抗原0·2ml加入白细胞悬液0·2ml和血浆0·3ml;④生理盐水0·2ml加入白细胞悬液0·2ml和血浆0·3ml。结果癌细胞、卡介苗和酵母菌能激活血液免疫反应,但没有加血浆组中,这些抗原不能激活血液免疫反应,在这些抗原加入全血细胞和血浆组,IL-8激活指数(2·124±0·860)明显高于这些抗原加入白细胞和血浆组的IL-8激活指数(0·390±0·080),P<0·01。结论结果表明在血液免疫反中存在红细胞和白细胞免疫反应主干道路线图,红细胞和补体在血液免疫反应路线图中具有重要作用。 相似文献
9.
Options for Immunologic Support of Renal Transplantation Through the HLA and Immunology Laboratories
HLA and immunology laboratories are an integral part of clinical kidney transplant programs. They assist transplant clinicians with evaluating the immunological suitability of potential recipients for transplantation and selecting donor-recipient combinations with a low risk of immunological failure. With sophisticated new techniques becoming available for posttransplant immunological monitoring, laboratories play an increasing supporting role during posttransplant follow up. The level of precision at which immunological testing predicts clinical outcome, however, leaves room for improvement. In this article, we summarize the current state of diagnostics, discuss problems, and point out promising developments. 相似文献
10.
目的 探讨获得性大疱性表皮松解症(EBA)基底膜带自身抗体(BMZ—Ab)的靶抗原及其定位情况。方法 用免疫印迹(IB)、盐裂皮肤间接免疫荧光(IIF)、间接免疫电镜(IIEM)等方法检测6例EBA血清中。IgG型及IgA型BMZ—Ab识别的真表皮抗原以及抗原定位情况。结果 6例EBA血清中IgG型BMZ—Ab均结合真皮提取物中290ku蛋白,3例同时伴有结合290ku蛋白的IgA型BMZ—Ab。盐裂皮肤IIF显示BMZ真皮侧IgG线状沉积,IIEM示金颗粒沉积于BMZ致密下层,即真皮锚原纤维的Ⅶ型胶原处。结论 位于BMZ致密下层的Ⅶ型胶原是EBA中BMZ-Ab的特异性靶抗原,Ⅶ型胶原上的抗原表位可被EBA血清中IgG及IgA型BMZ—Ab识别。 相似文献