Transforming growth factor-beta 1 in adipose derived stem cells conditioned medium is a dominant paracrine mediator determines hyaluronic acid and collagen expression profile

Conditioned medium from adipose derived stem cells (ADSC-CM) stimulates both collagen synthesis and migration of fibroblasts, and accelerates wound healing in vivo. Recently, the production and secretion of growth factors has been identified as an essential function of adipose-derived stem cells (ADSCs). However, the main soluble factor of ADSC-CM which mediates paracrine effects and its underlying mechanism has not been elucidated yet. In this study, we considered transforming growth factor-beta1 (TGF-β1) as a strong candidate for paracrine effect of ADSC-CM and investigated collagen synthesis and hyaluronic acid synthase (HAS) expression. After ADSC-CM addition, collagen type I, type III, HAS and hyaluronic acid (HA) expressions on human dermal fibroblasts (HDFs) were evaluated. Furthermore, to clarify effects of TGF-β1 as a paracrine mediator, TGF-β1 antibody and external supplementary TGF-β1 were treated to HDFs. Collagens type I, type III, HAS-1 and HAS-2 mRNA expressions of HDFs were greatly increased by ADSC-CM treatment, however there was no change in TGF-β1 antibody treated HDFs compared with non-treated control. These results strongly demonstrate that TGF-β1 plays an important role as a paracrine mediator of ECM synthesis. The fact that TGF-β1 contained in ADSC-CM not only accelerates collagen deposition but also increase hyaluronic acid synthesis of HDFs through HAS-1 and HAS-2 expression was also elucidated in this study. Therefore, ADSC-CM shows promise for the treatment of cutaneous wounds and accelerates granulation formation during healing process.     

利用启动子缺陷型打靶载体敲除五指山小型猪GGTA1基因

目的:获得α-1,3-半乳糖基转移酶(GGTA1)基因敲除的五指山小型猪胎儿,为异种器官移植研究提供基础平台。方法:以新霉素磷酸转移酶基因(neo)为筛选标记基因构建启动子缺陷型打靶载体,打靶载体线性化后用电转染法将其导入胎儿成纤维细胞中,转染后的细胞经G418筛选后,用PCR法检测药物抗性的细胞克隆,对阳性细胞进行核移植构建重构胚胎及胚胎移植。结果:转染后,经筛选共得到176个具有G418抗性的细胞克隆,经PCR检测,其中2个细胞克隆发生了同源重组;以其中1个GGTA1+/-细胞克隆为供体细胞进行核移植,将重构胚移植到2头自然发情的受体母猪中,1头受体妊娠;第37 d将代孕母猪处死,获得2个胎儿,经PCR和Southern印迹鉴定,均为GGTA1单等位基因敲除胎儿。结论:构建了五指山小型猪GGTA1基因部分外显子4区域敲除的启动子缺陷型打靶载体,获得了GGTA1单等位基因敲除的胎儿,为培育GGTA1基因敲除的五指山小型猪奠定了基础。     

羟基喜树碱抑制人眼Tenon囊成纤维细胞增殖的实验研究

目的：研究羟基喜树碱（HCPT）对体外培养的人眼Tenon囊成纤维细胞（Human Tenon＇s capsule fibroblasts,HTFs）增殖、移行的影响。方法：取正常供体新鲜的Tenon囊组织,采用组织块培养法,进行成纤维细胞的体外培养,并用光镜、免疫荧光法观察鉴定;MTT法、划痕法检测不同浓度的HCPT（0、0．031、0．062、0．125、0．25、0．5、1、2、4mg／1）对HTFs增殖、移行的影响,并与MMC对比。结果：HTFs体外生长良好,经光镜和免疫荧光法观察鉴定为成纤维细胞;与空白对照组比较,HCPT（0．031-4mg／1）、MMC（0．0031-0．4mg／1）均能有效抑制HTFs的增殖,且呈一定的剂量、时间依赖性,HCPT作用24h、48h、72h的IC50分别为2．24mg／1、O．76mg／1、0．39mg／1,MMC作用24h、48h、72h的IC50分别为0．34mg／1、0．24mg／1、0．07mg／1;与空白对照组比较,HCPT（0．031-4mg／1）、MMC（O．0031-0．4mg／1）均能抑制HTFs迁移,呈剂量依赖性,而与时间无显著相关。结论：HCPT、MMC均能有效抑制HTFs的增殖和移行,其效应MMC约为HCPT的10倍。     

Epithelial-to-mesenchymal transition in fibrosis: Collagen type I expression is highly upregulated after EMT,but does not contribute to collagen deposition

The hallmark of fibrosis is an accumulation of fibrillar collagens, especially of collagen type I. There is considerable debate whether in vivo type II epithelial-to-mesenchymal transition (EMT) is involved in organ fibrosis. Lineage tracing experiments by various groups show opposing data concerning the relative contribution of epithelial cells to the pool of myofibroblasts. We hypothesized that EMT-derived cells might directly contribute to collagen deposition. To study this, EMT was induced in human epithelial lung and renal cell lines in vitro by means of TGF-β1 stimulation, and we compared the collagen type I (COL1A1) expression levels of transdifferentiated cells with that of myofibroblasts obtained by TGF-β1 stimulation of human dermal and lung fibroblasts. COL1A1 expression levels of transdifferentiated epithelial cells appeared to be at least one to two orders of magnitude lower than that of myofibroblasts. This was confirmed at immunohistochemical level: in contrast to myofibroblasts, collagen type I deposition by EMT-derived cells was not or hardly detectable. We postulate that, even when type II EMT occurs in vivo, the direct contribution of EMT-derived cells to collagen accumulation is rather limited.     

Cryopreservation of an artificial human oral mucosa stroma. A viability and rheological study

The aim of this study was to evaluate the viability and biomechanical properties of artificial human oral mucosa stroma (HOMS) subjected to cryopreservation with different cryoprotectant solutions.     

Markers of breast cancer stromal fibroblasts in the primary tumour site associated with lymph node metastasis: a systematic review including our case series

CAFs (cancer-associated fibroblasts), the most abundant cell type in breast cancer stroma, produce a plethora of chemokines, growth factors and ECM (extracellular matrix) proteins, that may contribute to dissemination and metastasis. Axillary nodes are the first metastatic site in breast cancer; however, to the present date, there is no consensus of which specific proteins, synthesized by CAFs, might be related with lymph node involvement. The purpose of this study was to perform a systematic review of CAF biomarkers associated with the presence of regional metastasis. PubMed was searched using the words: ‘breast cancer’ and ‘lymph node’ and fibroblast or stroma or microenvironment. After exclusions, eight studies evaluating biomarkers immunoexpression in CAFs and lymph node status were selected. Biomarkers evaluated in these studies may be divided in two groups, according to their ontology: extracellular matrix components [MMP13 (matrix metalloproteinase 13), TIMP2 (tissue inhibitor of metalloproteinases-2), THBS1 (thrombospondin 1), LGALS1 (lectin, galactoside-binding, soluble, 1)] and response to wounding [PDPN (podoplanin), PLAU (plasminogen activator, urokinase), PLAUR (plasminogen activator, urokinase receptor), CAV1 (caveolin 1), THBS1, LGALS1]. A positive expression of MMP13 and LGALS1 in CAFs was associated with enhanced OR (odds ratio) for regional metastasis. Contrariwise, CAV1 positive staining of fibroblasts was associated with decreased OR for nodal involvement. Expression of MMP13, PDPN and CAV1 was further tested in a new series of 65 samples of invasive ductal breast carcinomas by immunohistochemistry and no association between biomarkers expression in CAFs and nodal status was found. It was suggested that breast cancer subtypes may differentially affect CAFs behaviour. It would be interesting to evaluate the prognostic significance of these biomarkers in CAFs from different tumour types.     

SHP-2激活突变促进小鼠MEFs细胞粘附迁移及增殖能力

目的探讨SHP-2D61G/＋和SHP-2D61G/D61G激活突变对小鼠胚胎成纤维细胞（MEFs）粘附迁移及增殖能力的影响,并研究其发生的机制。方法雌雄小鼠合笼交配建立SHP-2D61G/＋、SHP-2D61G/D61G激活突变的小鼠MEFs细胞,并以SV40T抗原进行永生化;细胞粘附实验检测SHP-2D61G/＋、SHP-2D61G/D61G激活突变对MEFs细胞粘附能力的影响;Transwell体外迁移实验检测SHP-2D61G/＋、SHP-2D61G/D61G激活突变对MEFs细胞的迁移能力的影响;MTT法检测SHP-2D61G/＋、SHP-2D61G/D61G激活突变对MEFs细胞增殖能力的影响;Western Blot法检测p-ERK的表达水平。结果 （1）与对照组相比,SHP-2D61G/＋、SHP-2D61G/D61G激活突变组小鼠MEFs细胞粘附的细胞数明显增多,差异具有统计学意义;（2）与对照组相比SHP-2D61G/＋、SHP-2D61G/D61G激活突变组MEFs细胞迁移的细胞数增加,差异具有统计学意义;（3）MTT结果显示,SHP-2D61G/＋、SHP-2D61G/D61G激活突变的小鼠MEFs细胞增殖能力较对照组强,差异具有统计学意义;（4）Western Blot结果显示与对照组相比,无论是刚刚贴壁还是贴壁后30 min和60 min SHP-2D61G/＋、SHP-2D61G/D61G激活突变组其p-ERK的表达水平都增加。结论 SHP-2D61G/＋、SHP-2D61G/D61G激活突变促进小鼠MEFs细胞粘附迁移及增殖能力,其发生机制主要与p-ERK的表达水平增加有关。     

Protective effect of 4,4′-diaminodiphenylsulphone against oxidative stress but not to apoptotic stress in human diploid fibroblasts

Abstract

The antibiotic drug 4,4′-diaminodiphenylsulphone (DDS) is used to treat several dermatologic diseases, including Hansen's disease. This study confirmed the antioxidant nature of DDS in hydrogen peroxide (H₂O₂)-induced oxidative stress and assessed its role in other apoptotic stresses in human diploid fibroblasts (HDFs). Oxidative stress was effectively reduced by DDS in a dose-dependent manner. Moreover, the oxidative stress-induced increases in the levels of the p53 and p21 proteins were inhibited by pre-treatment with DDS. In addition, H₂O₂ and DDS increased the level of cytochrome P450 (CYP450) IIE1 in HDFs, implicating a role for DDS in H₂O₂ scavenging via the activation of CYP450. DDS treatment increased the activity of catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR), as well as the GSH/GSSG ratio, indicating activation of the glutathione system against oxidative stress. However, DDS showed no protective effects on HDFs against other apoptotic stimuli, such as thapsigargin and staurosporine, suggesting that DDS would act only against oxidative stress. Therefore, in addition to its antibiotic function, DDS is a potent antioxidant against H₂O₂-induced oxidative stress in HDFs.     

慢病毒直接诱导形成猪iPS细胞无需限定因子

为了证实慢病毒对细胞具有遗传修饰和重编程作用,在本实验中使用慢病毒感染猪胎儿成纤维细胞.结果显示:慢病毒介导的EGFP在猪胎儿成纤维细胞中稳定和高效表达,使用添加LIF和bFGF的细胞培养液,部分猪的胎儿成纤维细胞逐渐改变原有的纤维状形态,形成圆形的细胞,细胞逐步增殖形成细胞集落,细胞集落边界清晰,在饲养层上细胞集落生长迅速,具有稳定的生长性能和正常核型,细胞碱性磷酸酶染色为阳性,表达干细胞特有的标记Oct4、Nanog和SSEA1,在体外能够形成拟胚体,在体内分化形成包含三个生殖层的畸胎瘤.作为核移植的供体细胞,克隆胚的卵裂率为53.33%、桑椹胚率为9.03%、囊胚率为2.07%、孵化囊胚的总细胞数为26.5,在桑椹胚率和囊胚率方面显著低于猪普通胎儿成纤维细胞核移植克隆胚的发育能力(P<0.05).结果证实慢病毒能够直接使猪的胎儿成纤维细胞转变成iPS细胞,因此慢病毒将成为一种理想的材料和工具用于细胞的遗传修饰和细胞重构等方面的研究.