Stem cell therapy in inflammatory bowel disease: A promising therapeutic strategy?

Inflammatory bowel diseases are inflammatory, chronic and progressive diseases of the intestinal tract for which no curative treatment is available. Research in other fields with stem cells of different sources and with immunoregulatory cells(regulatory T-lymphocytes and dendritic T-cells) opens up new expectations for their use in these diseases. The goal for stem cell-based therapy is to provide a permanent cure. To achieve this, it will be necessary to obtain a cellular product, original or genetically modified, that has a high migration capacity and homes into the intestine, has high survival after transplantation, regulates the immune reaction while not being visible to the patient’s immune system, and repairs the injured tissue.     

炎症性肠病患者Th22细胞亚群和IL-22水平变化及其临床意义

目的 探讨Th22细胞亚群和血清白介素-22（IL-22）水平在炎症性肠病（IBD）患者中的变化及其临床意义。 方法 选取2016年1月至2018年4月我院收治的125例IBD患者作为研究对象,其中克罗恩病（CD）组患者65例,溃疡性结肠炎（UC）组患者60例。选取同期进行体检的健康者50例作为对照组。比较各组对象Th22细胞亚群,血清IL-22、C-反应蛋白(CRP)、红细胞沉降率（ESR）水平,并进行相关性分析。 结果 CD组和UC组患者Th22细胞比例及IL-22、CRP、ESR水平均显著高于对照组（均P结论 Th22细胞亚群和IL-22水平与IBD患者病情严重程度关系密切,提示Th22细胞亚群和IL-22可能参与IBD发病过程中的炎症过程。     

益生菌在炎症性肠病中的治疗作用

炎症性肠病(inflammatory bowel disease,IBD)包括溃疡性结肠炎(ulcerative colitis,UC)和克罗恩病(Crohn’s disease,CD)。随着对肠道微生物群在IBD发病机制中作用的认识不断深入,近年来益生菌广泛应用于IBD治疗。大量临床试验结果表明,益生菌治疗IBD的疗效主要体现在对UC和贮袋炎的治疗,对CD的疗效不明确。益生菌治疗IBD可能通过促进肠道微生物群平衡、改善肠道屏障功能、调节肠道黏膜免疫及营养物质代谢等途径。     

白介素23 及Th17 细胞在炎症性肠病的作用

炎症性肠病(Inflammatory Bowel Diseases,IBD),是一组病因未明的累及胃肠道的慢性炎症性疾病,一般指克罗恩病(Crohn’sdisease,CD)和溃疡性结肠炎(ulcerative colitis,UC)。目前认为它是由多种因素相互作用所致的一种自身免疫性疾病,主要包括免疫、环境以及遗传等因素,其中免疫在IBD的发生过程中起着极其重要的作用。以往研究认为与T辅助细胞(T Helper cells)Th1或Th2细胞反应的增强或减弱有关。然而最近研究发现一类新细胞亚群,称为Th17细胞,与之相关的细胞因子可导致包括肠道在内的多脏器病变。Th17细胞分化过程中又需要IL-23的参与,因此IL-23/Th17细胞在炎症性肠病患者肠道内过度表达可以解释肠组织损伤的新途径,并为制定新的治疗策略提出依据。本文就IL-23/Th17轴在炎症性肠病中的作用的研究进展作一综述。     

炎症性肠病动物模型的研究进展

克罗恩病和溃疡性结肠炎统称为炎症性肠病（IBD）,病因虽不明确,但对其发病机理已有了较多的了解。该病的发生是由于个体易感性、肠道菌群和粘膜免疫相互作用所致。炎症性肠病动物模型可通过化学性诱导、免疫学、遗传学等方法获得。三硝基苯磺酸与乙醇灌肠致炎法是目前最常用的方法,本文侧重概述介绍三硝基苯磺酸诱导的炎症性肠病的机制、模型、应用及优缺点,为疾病的研究、治疗和新药的开发提供指导。     

白细胞介素23受体、白细胞介素17A在炎症性肠病患者中的表达及临床意义

目的：通过检测白细胞介素23受体（1L-23R）及白细胞介素17A（IL-17A）在炎症性肠病（IBD）患者肠黏膜及血清中的表达水平,探讨其在IBD发病过程中的作用及意义。方法：收集32例克罗恩病（CD）患者、29例溃疡性结肠炎（UC）患者及27例对照者的内镜肠黏膜活检标本,采用荧光定量PCR技术检测肠黏膜内IL-23R、IL-17AmRNA的表达情况,免疫组化技术分析IL-23R、IL-17A在肠黏膜中的原位表达。结果：与健康对照组相比,CD及UC患者肠黏膜组织内IL-23RmRNA表达显著增高（P〈0．05）,CD及UC组间的表达量差异无统计学意义（P〉0．05）。CD及UC患者肠黏膜组织内IL-17AmRNA表达显著增高（P〈0．05）,CD组肠黏膜组织内IL．17AmRNA表达显著高于uc组（P〈0．05）。免疫组化分析显示IL-23R阳性细胞在CD与uc肠黏膜固有层内有较多表达,较正常黏膜内的肠上皮细胞相比,CD及UC患者肠黏膜IL-23R蛋白表达量最著增高（P〈0．05）,UC及CD组间的表达量差异无统计学意义（P〉0．05）。IL-17A阳性细胞在CD与UC肠黏膜固有层内有较多表达,较正常黏膜内的肠上皮细胞相比,CD及UC患者肠黏膜IL-17A蛋白表达量最著增高（P〈0．05）。结论：IL．23R及IL-17A在IBD患者肠黏膜中表达显著增高,提示IL-23R及IL-17A表达异常与IBD的发生发展密切相关,有可能成为IBD治疗的新靶点。     

溃疡性结肠炎小鼠肠道黏膜和盲肠内容物菌群差异比较

了解溃疡性结肠炎(UC)小鼠肠道黏膜菌群的构成及其与盲肠内容物菌群的差异, 探讨肠道菌群在UC小鼠发病中的作用。

12只C57BL/6N雄性小鼠随机分为正常组、治疗组和模型组, 每组4只。采用葡聚糖硫酸钠盐(DSS)进行造模, 采用柳氮磺胺吡啶灌胃进行治疗, 造模第8天处死全部小鼠。采用16S rRNA基因高通量测序法对肠道黏膜和盲肠内容物菌群进行测序分析。

UC小鼠肠道黏膜菌群与盲肠内容物菌群相比, OTU数量和多样性均降低; Beta多样性分析显示其黏膜和盲肠内容物菌群差异较正常小鼠更大。在门和属的分类水平上, UC小鼠黏膜菌群中变形菌门、疣微菌门、魏斯菌属和肠球菌属丰度较正常小鼠升高, 厚壁菌门和拟杆菌门丰度降低; 阿克曼菌属在UC小鼠黏膜和盲肠内容物菌群中增多, 颤螺菌属在治疗组小鼠黏膜和盲肠内容物菌群中均减少。此外, 黏膜菌群中脱铁杆菌门Mucispirillum菌属丰度较高; 盲肠内容物中拟杆菌属丰度较高。物种组成分析中, 颤螺菌属、Mucispirillum、志贺菌属、魏斯菌属和肠球菌属聚类在一起。

UC小鼠黏膜菌群与盲肠内容物菌群在群落组成、多样性、优势菌群等方面存在明显差异, 黏膜菌群在UC发病机制中可能发挥着主要的作用。

     

Interleukin 35 (IL-35) and IL-37: Intestinal and peripheral expression by T and B regulatory cells in patients with Inflammatory Bowel Disease

The aim of the study was to characterize and to quantify peripheral and tissue. IL-35— and IL-37—producing cells in Inflammatory Bowel Disease (IBD) patients. We studied a total of 38 active UC, 31 inactive UC, 17 active CD, and 13 inactive CD and 50 non-inflamed tissues as control group. Gene expression was measured by real time polymerase chain reaction (RT-PCR) and protein expression was evaluated in tissue by immunohistochemistry and in peripheral blood mononuclear cells by flow cytometry. Higher levels of IL-35 was produced by intestinal regulatory B cells and circulating regulatory CD4⁺ and CD8⁺ T cells in active vs. inactive disease or healthy donors (P < 0.05). The IL-37 was conspicuously synthesized by circulating B cells, active natural killer cells and monocytes. These results suggest that down-regulation of inflammation in active IBD patients might be based on the increased expression of IL-35 and IL-37.     

Intestinal Epithelial Cell Autophagy Is Required to Protect against TNF-Induced Apoptosis during Chronic Colitis in Mice

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Mallotus philippinensis bark extracts promote preferential migration of mesenchymal stem cells and improve wound healing in mice

In the present study, we report the effects of the ethanol extract from Mallotus philippinensis bark (EMPB) on mesenchymal stem cell (MSC) proliferation, migration, and wound healing in vitro and in a mouse model. Chemotaxis assays demonstrated that EMPB acted an MSC chemoattractant and that the main chemotactic activity of EMPB may be due to the effects of cinnamtannin B-1. Flow cytometric analysis of peripheral blood mononuclear cells in EMPB-injected mice indicated that EMPB enhanced the mobilization of endogenous MSCs into blood circulation. Bioluminescent whole-animal imaging of luciferase-expressing MSCs revealed that EMPB augmented the homing of MSCs to wounds. In addition, the efficacy of EMPB on migration of MSCs was higher than that of other skin cell types, and EMPB treatment improved of wound healing in a diabetic mouse model. The histopathological characteristics demonstrated that the effects of EMPB treatment resembled MSC-induced tissue repair. Taken together, these results suggested that EMPB activated the mobilization and homing of MSCs to wounds and that enhancement of MSC migration may improve wound healing.     

间充质干细胞外泌体在阿尔兹海默症治疗中的研究进展

阿尔兹海默症（AD）是一种病理机制复杂,以进行性认知功能障碍为主的中枢神经系统疾病,目前仍缺乏有效的治疗方法。多项研究结果显示,间充质干细胞（MSCs）外泌体能够促进抗炎、调节免疫功能、加强Aβ降解、促进神经细胞轴突生长等,能很好地针对AD的核心病理机制发挥效果从而达到治疗效果。本文主要介绍MSCs外泌体在各项AD病理机制治疗中的研究进展。     

Evaluation of bone marrow derived mesenchymal stem cells for full-thickness wound healing in comparison to tissue engineered chitosan scaffold in rabbit

Background

Chronic wounds present a major challenge in modern medicine. Even under optimal conditions, the healing process may lead to scarring and fibrosis. The ability of mesenchymal stem cells (MSCs) to differentiate into other cell types makes these cells an attractive therapeutic tool for cell transplantation. Both tissue-engineered construct and MSC therapy are among the current wound healing procedures and potential care. Chitosan has been widely applied in tissue engineering because of its biocompatibility and biodegradability.

Exploring the stem cell and non-stem cell constituents of human breast milk

The immense potency of nutritional components of human breast milk and importance of breastfeeding is known worldwide. Recent researches had identified stem cells as integral component of human breast milk. Nevertheless, there is little proof of evidence on the stem cell constituents of breast milk. It is imperative to explore the cellular constituents of human breast milk, including of stem cells, to open new avenue in child’s development and regeneration. Thus, we aimed at identifying the cellular constituents of human breast milk by phenotypic characterisation of diverse cell surface markers of hematopoietic stem cells (CD 34, CD 133, CD 117), mesenchymal stem cells (CD 90, CD 105, CD 73), myoepithelial cells (CD 29, CD 44), Immune cells (CD 209, CD 86, CD 83, CD 14, CD 13, HLADR, CD 45), as well as cell adhesion molecules (CD 31, CD 54, CD 166, CD 106, CD 49d), and other markers (ABCG2, CD140b) using flowcytometry. We found a lower expression of CD 34 (13.07 ± 2.0 %), CD 90 (7.79 ± 0.8 %) and CD 73 (2.19 ± 0.41 %), indicating scanty hematopoietic and mesenchymal stem cell population in human breast milk. On contrary, myoepithelial progenitors, cell adhesion molecules, immune cells and growth factors were identified as the major constituents of breast milk. Overall, this study illuminates the benefits of breast feeding as breast milk encompasses heterogeneous cellular components that benefits child’s growth, immunity and development. However, further research on these constituents of human breast milk will widen their applicability in treatment of neonatal disorders.