Establishment and Characterization of a Cell Based Artificial Antigen-Presenting Cell for Expansion and Activation of CD8+ T Cells Ex Vivo

Atificial antigen-presenting cells are expected to stimulate the expansion and acquisition of optimal therapeutic features of T cells before infusion. Here CD32 that binds to a crystallizable fragment of IgG monoclonal antibody was genetically expressed on human K562 leukemia cells to provide a ligand for T-cell receptor. CD86 and 4-1BBL, which are ligands of CO. stimulating receptors of CD28 and 4-1BB. respectively, were also expressed on K562 cells. Then we accomplished the artificial antigen-presenting cells by coupling K32, CD86/4-IBBL cell with OKT3 monoclonal antibody against CD3.named K32/CD86/4-lBBL/OKT3 cells. These artificial modified cells had the abilities of inducing CD8+ T cell activation. promoting CD8+ T cell proliferation, division, and long-term growth, inhibiting CD8+ T cell apoptosis, and enhancing CD8+ T cell secretion of IFN-Y and perforin. Furthermore, antigen. secific cytotoxic T lymphocytes could be retained in the culture stimulated with K32/CD86/4-1BBL/OKT3 cells at least within 28 day This approach was robust, simple, reproducible and economical for expansion and activation of CD8+ T cells and may have important therapeutic implications for adoptive immunotherapy. Cellular & Molecular Immunology.2007;5(1):47-53.     

数字化大鼠动脉血管系统三维模型的建立

采用含造影剂及显色剂的填充剂对成年SD大鼠动脉血管系统进行灌注,并借助数字X射线成像设备对灌注效果进行实时监测,通过断层解剖成像系统获取切削间距为100 μm的二维断面解剖数据集(图像分辨率为4917×3446×24 bit,共1 464张),最后利用Visual C 结合可视化工具包编程实现数据集的动脉分割及三维可视化,得到数字化SD大鼠动脉血管系统的三维模型.该模型能提供大鼠动脉血管系统的空间结构信息,为实验大鼠血管系统的研究提供了更为准确可靠的形态学参考.     

Positive association of the <Emphasis Type="Italic">FTSJ1</Emphasis> gene polymorphisms with nonsyndromic X-linked mental retardation in young Chinese male subjects

To investigate the possible genetic association of nonsyndromic X-linked mental retardation (NS-XLMR) with FTSJ1 gene polymorphisms, a case-control association study was performed focusing on the Chinese Han population in the Qinba mountain region. Three common single nucleotide polymorphisms (SNPs) (rs2268954, rs2070991, rs5905692) in the gene were selected and genotyped using the polymerase chain reaction single-strand confirmation polymorphism (PCR-SSCP) method. Pairwise linkage disequilibrium (LD) analysis showed that the three SNPs were in strong LD (all D' > 0.8). There were significant differences between cases and controls in allele frequency distribution of rs2268954 (P = 0.036), rs2070991 (P = 0.043), and rs5905692 (P = 0.014) and in the distributions of common haplotypes combined by these SNPs (global P = 0.01236) in male subjects. In female subjects, however, no positive results were found. Our results suggest a positive association between the genetic variants of the FTSJ1 gene and NS-XLMR in young male subjects in the Chinese Han population in the Qinba region.     

一种基于自适应最小模糊熵的CT图像分割方法

为了从CT图像中提取到多个组织的解剖特征,解决运算速度的提高与运算结果不稳定的矛盾,我们提出了一种基于自适应最小模糊熵的图像分割算法.为了找到分割灰度图像的最佳阈值.首先利用迭代公式以及图像的直方图来计算出每个模糊子集的隶属函数中指数参数的值以及阈值的搜索范围,然后在已确定的搜索范围内用穷举法搜索出能使模糊熵最小的最佳阈值.实验表明该方法能较好的完成CT图像的分割.此算法运算速度较快;与用遗传算法、模拟退火算法相比较,运算结果稳定,重复性更好,得到的图像细节成分要更多些.     

中国汉族人与美国高加索白人膝关节几何形态的比较

背景:有研究显示中国人膝关节胫骨近端前后径和横径均小于美国高加索人,所以在膝关节形态学方面存在一定差异,因此常发生进口假体系统应用于国人后出现匹配度不高的现象。目的:测量中国人和美国人股骨远端、胫骨近端的几何形态学参数,比较其差异。方法:选择北京清华长庚医院骨科拟行前交叉韧带重建的中国汉族患者50例,以及美国匹兹堡大学运动医学中心拟行前交叉韧带重建的高加索白人后裔患者40例,对90例受试者膝关节进行CT扫描,使用AW Volume Share 5软件进行三维重建,利用Geomagic软件对胫骨近端和股骨远端的各项参数进行测量。结果与结论:①股骨近端测量参数中,中国人的外侧胫骨平台内外径小于美国人(P=0.027),外侧胫骨平台后倾角大于美国人(P<0.05);两组间胫骨平台内外径、内侧胫骨平台外径、内侧胫骨平台前后径、外侧胫骨平台前后径与内侧胫骨平台后倾角比较差异均无显著性意义(P>0.05);②股骨远端测量参数中,中国人的股骨远端横径、外侧髁内外径、内侧髁前后径、外侧髁前后径及髁间窝高度均小于美国人(P<0.05),股骨外翻角大于美国人(P<0.05);两组间内侧髁内外径、髁间窝宽度及滑车沟宽度比较差异无显著性意义(P>0.05);③结果表明,中国人与美国人在膝关节形态学的多个参数存在差异,有必要针对中国人设计更为个体化的膝关节假体。     

人工真皮支架联合灌洗式负压封闭引流在肌腱或骨外露创面修复中的应用

目的探讨人工真皮支架联合灌洗式负压封闭引流修复肌腱或骨外露创面的疗效。 方法选择2018年1月至2020年1月安徽医科大学第一附属医院烧伤科收治的肌腱或骨外露创面39例,其中急性创面26例(外伤10例,烧伤11例,热压伤4例,虫咬伤1例);慢性创面13例(糖尿病足皮肤溃疡2例,烧伤后期创面7例,瘢痕溃疡4例)。在全身麻醉或神经阻滞下行创面清创,在肌腱或骨外露处植入加强型人工真皮支架,外加负压封闭引流敷料覆盖,术后使用不同冲洗液进行间歇性灌洗,直至组织红润,达到二期植皮手术要求。观察并记录人工真皮支架使用次数,清创后人工真皮支架植入与二期植皮间隔时间和植皮成活情况。 结果39例肌腱或骨外露的急慢性创面经清创后覆盖人工真皮支架,术后经不同冲洗液间歇性灌洗式负压封闭引流治疗,均形成新鲜肉芽组织,二期经刃厚皮片植皮手术,植皮均100%成活,未出现感染等并发症。 结论人工真皮支架植入联合灌洗式负压封闭引流可有效地覆盖外露的肌腱和骨,是急慢性创面合并肌腱、骨外露的有效修复方式之一。     

非小细胞肺癌影像学特征与基因表达间相关性的探索性研究

影像基因组学通过挖掘肿瘤的影像和基因组学间的关联性,将两者的优势互补,以此指导不同患者个体化治疗方案的制定、预后评估、疗效检测等。针对非小细胞肺癌(NSCLC),建立其CT影像定量特征与基因表达之间的映射。首先,将对应的CT影像中肿瘤区域进行分割和特征提取,选用66种三维定量特征作为肿瘤区域影像特征集;然后,利用基因组学数据分析流程,在原始基因数据经过预处理、聚类后,获取其第一主成分作为具有相似表达谱基因聚类结果的代表;最后,运用基因芯片显著性分析算法探寻两者之间的相关性,并进行基因集的富集分析和预测模型的建立。对癌症图像归档数据库(TCIA)中的26例NSCLC影像数据和基因表达综合数据库(GEO)中相对应的基因数据进行分析,共得到126组成对的显著关联(q<0.05)。将所得结果中的29组元基因建立预测模型,并通过TCIA中更新的211组数据,对其中10组预测准确率大于70%且预测的元基因有生物学意义的预测模型进行验证,最终预测准确率为35.48%～80.85%,10个预测模型中有6个的准确率在70%以上。实验结果表明,特定的影像特征或其组合可以作为基因表达的影像标记物。     

Interleukin-33 alleviates psoriatic inflammation by suppressing the T helper type 17 immune response

Psoriasis is a chronic inflammatory skin disease with unclear pathogenesis. Interleukin-33 (IL-33) is highly expressed in patients with psoriasis, but its role in psoriasis is unknown. The aim of this study was to investigate the possible role of IL-33 in the pathogenesis and treatment of psoriasis. IL-33 expression was determined using enzyme-linked immunosorbent assay, real-time fluorescent quantitative polymerase chain reaction and immunohistochemical staining. CD4⁺ T cells were sorted using magnetic beads and treated with or without IL-33. Imiquimod (IMQ) was used to induce psoriatic inflammation in mice. The frequency of immune cells was determined using flow cytometry. The cytokine level in mouse skin was measured using cytometric bead array. Our results showed that IL-33 was highly expressed in the lesional skin and serum of patients with moderate-to-severe plaque psoriasis. IL-33 inhibited the expression of IL-17 in CD4⁺ T cells of psoriasis patients. Subcutaneous injection of IL-33 alleviated the IMQ-induced psoriatic inflammation in mice, reduced tumor necrosis factor-α and IL-23 expression, and decreased the proportion of T helper type 17 (Th17) cells in the skin-draining lymph nodes in the mice. Our results suggest that IL-33 plays a protective role in the pathogenesis of psoriasis by suppressing Th17 cell differentiation and function. The potential therapeutic effect of IL-33 in treating psoriasis warrants further investigation.     

Surface characterization and cytocompatibility of three chitosan/polycation composite membranes for guided bone regeneration

Guided bone regeneration is a promising surgical procedure for reconstructing bone defects. In this study, three chitosan/polycation composite membranes for guided bone regeneration are produced by blending chitosan with poly-L-lysine, polyethyleneimine, and poly-L-ornithine. For all composite membranes, the surface characteristics including surface topography, chemistry, and wettability are examined by atomic force microscopy, X-ray photoelectron spectroscopy, and contact angle assay. Their cytocompatibility is also evaluated with MC3T3-E1 osteoblast-like cells at cell, protein, and gene levels through cell biology assays, western blot, and RT-PCR analysis. On chitosan/poly-L-lysine composite membrane, MC3T3-E1 cells present well-developed cytoskeletal organization and significantly higher adhesion, proliferation, and differentiation than those on chitosan and the other two composite membranes. Furthermore, MC3T3-E1 cells on chitosan/poly-L-lysine membrane exhibit increased phosphorylation levels of focal adhesion kinase and extracellular signal-regulated kinase 1/2, and achieve an enhanced mRNA expression of fibronectin, Runx 2, RhoA, integrin alpha 5, and integrin beta1. From our results, we conclude that chitosan/ poly-L-lysine composite membrane possesses improved cytocompatibility with osteoblasts when compared to chitosan and holds potential for guided bone regeneration in the near future.     

Dysregulation of Insulin Signaling,Glucose Transporters,O-GlcNAcylation,and Phosphorylation of Tau and Neurofilaments in the Brain : Implication for Alzheimer’s Disease

Recent studies have suggested a possible role of insulin dysfunction in the pathogenesis of sporadic Alzheimer’s disease (AD). In AD, brain glucose metabolism is impaired, and this impairment appears to precede the pathology and clinical symptoms of the disease. However, the exact contribution of impaired insulin signaling to AD is not known. In this study, by using a nontransgenic rat model of sporadic AD generated by intracerebroventricular administration of streptozotocin, we investigated insulin signaling, glucose transporters, protein O-GlcNAcylation, and phosphorylation of tau and neurofilaments in the brain. We found impaired insulin signaling, overactivation of glycogen synthase kinase-3β, decreased levels of major brain glucose transporters, down- regulated protein O-GlcNAcylation, increased phosphorylation of tau and neurofilaments, and decreased microtubule-binding activity of tau in the brains of streptozotocin-treated rats. These results suggest that impaired brain insulin signaling may lead to overactivation of glycogen synthase kinase-3β and down-regulation of O-GlcNAcylation, which, in turn, facilitate abnormal hyperphosphorylation of tau and neurofilaments and, consequently, neurofibrillary degeneration.Alzheimer’s disease (AD), the most devastating chronic neurodegenerative disease in adults, causes dementia in, and eventually, death of the affected individuals. In less than 1% of cases, AD is caused by autosomal dominant mutations of presenilin-1, presenilin-2, or β-amyloid precursor protein. Most AD cases are sporadic and are believed to result from multiple etiologic factors including genetic susceptibility (such as the ApoE4 allele) and environmental and metabolic factors.¹ One of these factors, impaired brain glucose metabolism, can be detected many years before the appearance of clinical symptoms of AD.² We recently found that altered O-GlcNAcylation, an O-linked post-translational modification of nucleocytoplasmic proteins by a monosaccharide β-N-acetylglucosamine (O-GlcNAc), of the microtubule-associated protein tau, links the impairment of brain glucose metabolism to hyperphosphorylation of tau.^3,4 On the basis of these findings, we hypothesized that the impairment of brain glucose metabolism contributes to neurodegeneration via down-regulation of O-GlcNAcylation, which is regulated by glucose metabolism, and the resultant abnormal hyperphosphorylation of tau, which is crucial to neurodegeneration in AD.⁵Peripheral glucose metabolism is mainly regulated by insulin. Recent studies have indicated that insulin signaling also regulates glucose metabolism in the brain and plays important roles in neural development and neuronal activities and affects learning and memory.⁶ The role of possible insulin dysfunction in AD has been suggested recently.^7,8,9,10 However, how the impaired insulin signaling contributes to the pathogenesis of AD is not known.To investigate the possible pathogenic mechanism related to the impaired brain insulin signaling and glucose metabolism in sporadic AD, we investigated insulin signaling pathways, glucose transporters (GLUT), protein O-GlcNAcylation and phosphorylation of tau and neurofilaments (NFs) in a rat model of sporadic AD, which was generated by intracerebroventricular (i.c.v.) injection of streptozotocin (STZ).^11,12,13 STZ is a glucosamine-nitrosourea compound and is commonly administrated peripherally to generate animal models of diabetes because of its ability to damage insulin-producing cells and to increase insulin resistance. We found the impaired insulin signaling pathway, overactivation of glycogen synthase kinase-3β (GSK-3β), decreased major glucose transporters, down-regulation of protein O-GlcNAcylation, increased phosphorylation of tau and NFs, and decreased microtubule-binding activity of tau in the brain of the rat model of AD. Our results provide in vivo evidence showing that impaired brain insulin signaling and O-GlcNAcylation contribute to hyperphosphorylation of tau and NFs.