Immunotherapy with chimeric NKG2D receptors leads to long-term tumor-free survival and development of host antitumor immunity in murine ovarian cancer

Ovarian cancer is one of the leading causes of cancer death in women and the development of novel therapies is needed to complement the standard treatment options such as chemotherapy and radiation. In this study, we show that treatment with T cells expressing a chimeric NKG2D receptor (chNKG2D) was able to lead to long-term, tumor-free survival in mice bearing established ovarian tumors. Tumor-free mice were able to reject a rechallenge with ovarian tumor cells 225 days after original tumor injection. In addition, chNKG2D T cell treatment induced specific host immune responses to ovarian tumor cells, including the development of both CD8+ and CD4+ T cell tumor-specific memory responses. The chNKG2D T cells reduced the ovarian tumor burden using both cytotoxic and cytokine-dependent pathways. Specifically, chNKG2D T cell expression of perforin, GM-CSF, and IFN-gamma were essential for complete antitumor efficacy.     

A Kalman-Filter Based Approach to Identification of Time-Varying Gene Regulatory Networks

Motivation

Conventional identification methods for gene regulatory networks (GRNs) have overwhelmingly adopted static topology models, which remains unchanged over time to represent the underlying molecular interactions of a biological system. However, GRNs are dynamic in response to physiological and environmental changes. Although there is a rich literature in modeling static or temporally invariant networks, how to systematically recover these temporally changing networks remains a major and significant pressing challenge. The purpose of this study is to suggest a two-step strategy that recovers time-varying GRNs.

Results

It is suggested in this paper to utilize a switching auto-regressive model to describe the dynamics of time-varying GRNs, and a two-step strategy is proposed to recover the structure of time-varying GRNs. In the first step, the change points are detected by a Kalman-filter based method. The observed time series are divided into several segments using these detection results; and each time series segment belonging to two successive demarcating change points is associated with an individual static regulatory network. In the second step, conditional network structure identification methods are used to reconstruct the topology for each time interval. This two-step strategy efficiently decouples the change point detection problem and the topology inference problem. Simulation results show that the proposed strategy can detect the change points precisely and recover each individual topology structure effectively. Moreover, computation results with the developmental data of Drosophila Melanogaster show that the proposed change point detection procedure is also able to work effectively in real world applications and the change point estimation accuracy exceeds other existing approaches, which means the suggested strategy may also be helpful in solving actual GRN reconstruction problem.     

中国人β神经生长因子前体基因的克隆及其序列分析

从正常人外周血白细胞中提取基因组ＤＮＡ,用ＰＣＲ扩增神经生长因子（ＮＧＦ）β亚基前体的全长编码区序列,将其克隆到Ｔ－ｖｅｃｔｏｒ（原始质粒为ｐＢｌｕｅｓｃｒｉｐｔⅡＳＫ（＋））上,取两个独立的克隆采用自动测序仪进行双链ＤＮＡ双向测序,结果表明：两个克隆的序列完全相同,该序列与国外报道的ＮＧＦ序列有一个碱基的差别,从而导致ＮＧＦ前导肽中一个氨基酸的改变,而成熟的ＮＧＦ序列没有改变。     

Selection of Treatment Strategies among Patients with Type 2 Diabetes Mellitus in Malaysia: A Grounded Theory Approach

Background

Diabetes Mellitus is a multifaceted chronic illness and its life-long treatment process requires patients to continuously engage with the healthcare system. The understanding of how patients manoeuvre through the healthcare system for treatment is crucial in assisting them to optimise their disease management. This study aims to explore issues determining patients’ treatment strategies and the process of patients manoeuvring through the current healthcare system in selecting their choice of treatment for T2DM.

Methods

The Grounded Theory methodology was used. Twelve patients with Type 2 Diabetes Mellitus, nine family members and five healthcare providers from the primary care clinics were interviewed using a semi-structured interview guide. Three focus group discussions were conducted among thirteen healthcare providers from public primary care clinics. Both purposive and theoretical samplings were used for data collection. The interviews were audio-taped and transcribed verbatim, followed by line-by-line coding and constant comparison to identify the categories and core category.

Results

The concept of “experimentation” was observed in patients’ help-seeking behaviour. The “experimentation” process required triggers, followed by information seeking related to treatment characteristics from trusted family members, friends and healthcare providers to enable decisions to be made on the choice of treatment modalities. The whole process was dynamic and iterative through interaction with the healthcare system. The decision-making process in choosing the types of treatment was complex with an element of trial-and-error. The anchor of this process was the desire to fulfil the patient’s expected outcome.

Conclusion

Patients with Type 2 Diabetes Mellitus continuously used “experimentation” in their treatment strategies and help-seeking process. The “experimentation” process was experiential, with continuous evaluation, information seeking and decision-making tinged with the element of trial-and-error. The theoretical model generated from this study is abstract, is believed to have a broad applicability to other diseases, may be applied at varying stages of disease development and is non-context specific.     

汉族马凡综合征(MFS)患者FBN1基因两种新发突变分析

为调查马凡综合征(Marfan syndrome, MFS)患者的原纤维蛋白-1(Fibrillin-1, FBN1)基因突变情况, 应用聚合酶链反应(PCR)和变性高效液相色谱法(Denaturing high-performance liquid chromatography, DHPLC)对MFS患者的FBN1基因进行突变筛查, 对DHPLC初筛异常的DNA片段进行测序分析。结果在两个MFS家系中发现FBN1基因两种新的突变: 一种为复合突变包含第55号外显子的缺失突变c.6862_6871delGGCTGTGTAG (p.Gly2288MetfsX109)、同义突变c.6861A>G和内含子的突变c.[6871+1_6871+11delGTAAGAGGATC; 6871+34dupCATCAGAAGTGACAGTGGACA]; 另一种为第20号外显子的错义突变c.2462G>A(p.Cys821Tyr)。研究表明, FBN1基因的缺失突变c.[6862_6871delGGCTGTGTAG; 6871+1_6871+11delGTAAGAGGATC] (p.Gly2288MetfsX109)和错义突变c.2462G>A(p.Cys821Tyr)可能分别是这两个家系患者的致病原因。     

Mutation Inactivation of Nijmegen Breakage Syndrome Gene (NBS1) in Hepatocellular Carcinoma and Intrahepatic Cholangiocarcinoma

Nijmegen breakage syndrome (NBS) with NBS1 germ-line mutation is a human autosomal recessive disease characterized by genomic instability and enhanced cancer predisposition. The NBS1 gene codes for a protein, Nbs1(p95/Nibrin), involved in the processing/repair of DNA double-strand breaks. Hepatocellular carcinoma (HCC) is a complex and heterogeneous tumor with several genomic alterations. Recent studies have shown that heterozygous NBS1 mice exhibited a higher incidence of HCC than did wild-type mice. The objective of the present study is to assess whether NBS1 mutations play a role in the pathogenesis of human primary liver cancer, including HBV-associated HCC and intrahepatic cholangiocarcinoma (ICC). Eight missense NBS1 mutations were identified in six of 64 (9.4%) HCCs and two of 18 (11.1%) ICCs, whereas only one synonymous mutation was found in 89 control cases of cirrhosis and chronic hepatitis B. Analysis of the functional consequences of the identified NBS1 mutations in Mre11-binding domain showed loss of nuclear localization of Nbs1 partner Mre11, one of the hallmarks for Nbs1 deficiency, in one HCC and two ICCs with NBS1 mutations. Moreover, seven of the eight tumors with NBS1 mutations had at least one genetic alteration in the TP53 pathway, including TP53 mutation, MDM2 amplification, p14ARF homozygous deletion and promoter methylation, implying a synergistic effect of Nbs1 disruption and p53 inactivation. Our findings provide novel insight on the molecular pathogenesis of primary liver cancer characterized by mutation inactivation of NBS1, a DNA repair associated gene.     

固有免疫细胞及其模式识别受体与表观遗传学调控研究进展

固有免疫细胞是机体抵御病原微生物的首道防线,亦是机体有效启动和维持免疫反应的重要参与者,而模式识别受体是固有免疫细胞发挥免疫功能的重要免疫分子,因此,机体对固有免疫细胞及其模式识别受体的精细调控尤为重要。表观遗传学是近年研究热点,其在固有免疫调节中的作用逐渐受到重视。就近年表观遗传学中的DNA甲基化、组蛋白共价修饰及非编码RNA等在调节固有免疫细胞分化发育及其模式识别受体的相关研究作一简述,以期为感染、炎症、自身免疫病等研究与防治提供新的思路和策略。     

大叶杨组组间杂交花粉－柱头相互作用的超微结构研究

以大叶杨为母本,分别与小叶杨、欧洲黑杨、响叶杨进行人工杂交,并以大叶杨×大叶杨为对照,观察其花粉与柱头相互作用的超微结构变化。结果表明,大叶杨柱头细胞在授粉前表现生理活跃,含丰富的细胞器,壁外被含分支通道的角质层。接受大叶杨及欧洲黑杨花粉的柱头细胞内部仍有丰富的细胞器,膜结构保存完好。接受小叶杨及响叶杨花粉的柱头细胞衰亡较快,授粉部位沉积厚的胼胝质,细胞内部液泡化,膜结构逐渐消失,细胞质电子密度加大。欧洲黑杨花粉行为与大叶杨花粉行为相似,花粉能迅速萌发,并以短管形式穿入柱头,异常行为罕见。小叶杨及响叶杨花粉萌发后只有半数花粉管能以短管形式进入柱头,其中部分管内沉积胼胝质,另半数花粉管在柱头上表现各种异常行为——扭曲、爬行、肿胀、提前破裂释放内容物及先端沉积胼胝质。由各种花粉在大叶杨柱头上的行为和大叶杨柱头对各种授粉的反应判断,与大叶杨杂交亲和力在柱头阶段表现由强至弱依次是欧洲黑杨、小叶杨、响叶杨。     

Inhibition of repulsive guidance molecule,RGMa, increases afferent synapse formation with auditory hair cells

The peripheral fibers that extend from auditory neurons to hair cells are sensitive to damage, and replacement of the fibers and their afferent synapse with hair cells would be of therapeutic interest. Here, we show that RGMa, a repulsive guidance molecule previously shown to play a role in the development of the chick visual system, is expressed in the developing, newborn, and mature mouse inner ear. The effect of RGMa on synaptogenesis between afferent neurons and hair cells, from which afferent connections had been removed, was assessed. Contact of neural processes with hair cells and elaboration of postsynaptic densities at sites of the ribbon synapse were increased by treatment with a blocking antibody to RGMa, and pruning of auditory fibers to achieve the mature branching pattern of afferent neurons was accelerated. Inhibition by RGMa could thus explain why auditory neurons have a low capacity to regenerate peripheral processes: postnatal spiral ganglion neurons retain the capacity to send out processes that respond to signals for synapse formation, but expression of RGMa postnatally appears to be detrimental to regeneration of afferent hair cell innervation and antagonizes synaptogenesis. Increased synaptogenesis after inhibition of RGMa suggests that manipulation of guidance or inhibitory factors may provide a route to increase formation of new synapses at deafferented hair cells. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 74: 457–466, 2014