IL2/IL2R系统介导重组IL2-毒素融合蛋白靶向杀伤高表达 IL2R的恶性血液病细胞

恶性血液病的靶向杀伤治疗已成为必然的发展趋势 ,利用细胞因子与其受体的特异性结合来导向传递重组细胞因子 -毒素融合蛋白 ,以达到特异性杀伤高表达相应细胞因子受体恶性血液病细胞的新策略标志着肿瘤导向杀伤研究的最新进展之一。它较以抗原 -抗体为主体的第一代导向杀伤策略具有如下优势 :( 1 )导向的特异性更高、杀伤力更强 ;( 2 )细胞因子与毒素蛋白通过重组后以肽链相连 ,稳定性更好(3)重组细胞因子 -毒素融合蛋白不含碳水化合物而使其在血浆中的消除速度减慢、作用时间延长 ,且对肝肾细胞的损伤显著减小 ;( 4 )基因工程可进行工业化…     

Rescue of calcineurin Aα(-/-) mice reveals a novel role for the α isoform in the salivary gland

Calcineurin is an important signal transduction mediator in T cells, neurons, the heart, and kidneys. Recent evidence points to unique actions of the two main isoforms of the catalytic subunit. Although the β isoform is required for T-cell development, α is important in the brain and kidney. In addition, mice lacking α but not β suffer from failure to thrive and early mortality. The purpose of this study was to identify the cause of postnatal death of calcineurin α null (CnAα(-/-)) mice and to determine the mechanism of α activity that contributes to the phenotype. CnAα(-/-) mice and wild-type littermate controls were fed a modified diet and then salivary gland function and histology were examined. In vitro studies were performed to identify the mechanism of α action. Data show that calcineurin is required for normal submandibular gland function and secretion of digestive enzymes. Loss of α does not impair nuclear factor of activated T-cell activity or expression but results in impaired protein trafficking downstream of the inositol trisphosphate receptor. These findings show a novel function of calcineurin in digestion and protein trafficking. Significantly, these data also provide a mechanism to rescue to adulthood a valuable animal model of calcineurin inhibitor-mediated neuronal and renal toxicities.     

Human T-lymphoid progenitors generated in a feeder-cell-free Delta-like-4 culture system promote T-cell reconstitution in NOD/SCID/γc(-/-) mice

Slow T-cell reconstitution is a major clinical concern after transplantation of cord blood (CB)-derived hematopoietic stem cells. Adoptive transfer of in vitro-generated T-cell progenitors has emerged as a promising strategy for promoting de novo thymopoiesis and thus accelerating T-cell reconstitution. Here, we describe the development of a new culture system based on the immobilized Notch ligand Delta-like-4 (DL-4). Culture of human CD34(+) CB cells in this new DL-4 system enabled the in vitro generation of large amounts of T-cell progenitor cells that (a) displayed the phenotypic and molecular signatures of early thymic progenitors and (b) had high T lymphopoietic potential. When transferred into NOD/SCID/γc(-/-) (NSG) mice, DL-4 primed T-cell progenitors migrated to the thymus and developed into functional, mature, polyclonal αβ T cells that subsequently left the thymus and accelerated T-cell reconstitution. T-cell reconstitution was even faster and more robust when ex vivo-manipulated and nonmanipulated CB samples were simultaneously injected into NSG mice (i.e., a situation reminiscent of the double CB transplant setting). This work provides further evidence of the ability of in vitro-generated human T-cell progenitors to accelerate T-cell reconstitution and also introduces a feeder-cell-free culture technique with the potential for rapid, safe transfer to a clinical setting.     

载脂蛋白(a)启动子-418A/G位点和-384C/T位点单核苷酸多态性的研究

目的:研究载脂蛋白(a)启动子区-418位点和-384位点的单核苷酸多态性(SNP),比较种族间单核苷酸的基因型频率分布差异,探讨它们对血脂的影响及同冠状动脉疾病(CHD)的相关性。方法:采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)的分析方法,检测了中国湖北汉族人群无血缘关系的156名健康者及56例CHD患者和65例无血缘关系的非洲贝宁黑种人的Apo(a)启动子-418位点、-384位点单核苷酸的基因型,并对作为酶切底物的PCR产物进行了T-载体法克隆测序。同时,测定血清脂蛋白(a)、总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、ApoAI及ApoB浓度。结果:(1)在对照组中Apo(a)启动子区-418位点只存在等位基因A,未见等位基因G,只有AA基因型,-384位点只存在等位基因C,未见等位基因T,仅有CC基因型;CHD组中,-418位点仅检出1例突变型(GG型),-384位点只有CC型,未发现突变基因T。(2)贝宁黑种人组中,-418位点检出两例突变型(GG型),其他均为AA基因型;-384位点只存在等位基因C,也未发现突变基因T,只有CC基因型。(3)测序结果表明对照人群中Apo(a)基因启动子区(-541--341)序列与GenBank所公布的序列是一致的,并且-418位点碱基为A,-384位点碱基为C。结论:汉族人群中Apo(a)基因启动子区-418位点和-384位点碱基突变率较低,不构成单核苷酸多态性(SNP),与脂质水平及CHD未显示相关性;贝宁黑种人-418位点具有多态性;在种族间的SNP可能存在着较大的差异。     

IL4 and IL-17A provide a Th2/Th17-polarized inflammatory milieu in favor of TGF-β1 to induce bronchial epithelial-mesenchymal transition (EMT)

Severe asthma is a chronic airway disease characterized by the Th2/Th17-polarized inflammation along with permanent airway remodeling. Despite past extensive studies, the exact role for Th2 and Th17 cytokines in asthmatic pathoetiology, particularly in the pathogenesis of bronchial epithelial-mesenchymal transition (EMT), is yet to be fully addressed. We herein conducted studies in 16-HBE cells and demonstrated that Th2-derived IL-4 and Th17-derived IL-17A provide a chronic inflammatory milieu that favors TGF-β₁ to induce bronchial EMT. A synergic action was noted between TGF-β₁, IL-4 and IL-17A in terms of induction of EMT. IL-4 and IL-17A synergized with TGF-β₁ to induce epithelial cells re-entering cell cycle, and to promote epithelial to mesenchymal morphological transistion, and by which they enhanced the capacity of TGF-β₁ to suppress E-cadherin expression, and to induce a-SMA expression in epithelial cells. Mechanistic studies revealed that this synergic action is coordinated by the regulation of ERK1/2 activity. Our results not only provide a novel insight into the understanding of the mechanisms underlying airway remodeling in asthmatic condition, but also have the potential for developing more effective therapeutic strategies against severe asthmatics in clinical settings.     

Genotyping for cytokine polymorphisms in a Northern Ivory Coast population reveals a high frequency of the heterozygote genotypes for the TNF-α-308G/A SNP

Cytokine polymorphisms influence the outcomes of parasitic diseases and vary among populations because of their different evolutionary histories and selective pressures imposed by host-pathogen interactions. In this frame, we investigated the frequencies of TNF-α (-308G/A), TGF-β(1) (codon 10C/T, codon 25C/G) and IL-10 (-1082A/G) SNPs in 133 individuals from Ouangolodougou, a rural village in Northern Ivory Coast, where malaria and other parasitic diseases are endemic. The SNPs alleles were determined by ARMS-PCR methodology. Allele frequencies of the SNPs investigated were as follows: IL 10 -1082G = 0.741 and -1082A = 0.259; TGF-β(1) Codon 10 C = 0.835 and T = 0.165; TGF-β(1) Codon 25 G = 0.782 and C = 0.218. For the TNF-α gene, we found high frequencies of the -308A allele (0.305) and heterozygote genotypes (0.594), with a consequent deviation from the Hardy-Weinberg equilibrium. The high heterozygosity at the TNF-α locus suggests a possible selective advantage of the heterozygote genomes, associated with intermediate levels of TNF-α expression, against the infectious agents endemic in Western Africa.     

Interleukin (IL)-17A synergistically enhances CC chemokine ligand 20 production in IL-1β-stimulated human gingival fibroblasts

CC chemokine ligand 20 (CCL20) plays a pivotal role in the recruitment of T-helper (Th)-17 cells and thus in the development of periodontal disease, but the effect of simultaneous interleukin (IL)-17A and IL-1β stimulation on CCL20 production in human gingival fibroblasts (HGFs) are not known. In this study, we investigated the mechanisms of IL-1β- and IL-17A-induced CCL20 production in HGFs. IL-17A synergistically enhanced CCL20 production from IL-1β-stimulated HGFs in a concentration-dependent manner. Extracellular signal-regulated kinase (ERK) and inhibitor of nuclear factor (NF)-κB-α phosphorylation were increased in IL-1β- and IL-17A-stimulated HGFs. Inhibitors of or ERK and NF-κB decreased IL-1β- and IL-17A-induced CCL20 production. IL-1β stimulation elevated IL-17 receptor C expression on HGFs. These data suggest that IL-1β is actively related to Th17 cell migration into peripheral tissues to induce production of the Th17 chemokine, CCL20. Therefore, IL-1β might be a therapeutic target for Th17-related diseases, such as periodontal disease and arthritis.     

Neuromediators in inflammation—a macrophage/nerve connection

Macrophages are key players not only during initiation of inflammation but also during its resolution. This is achieved by their high functional plasticity and the demand to recognize an enormous repertoire of danger signals and cytokines/chemokines derived from adaptive immune cells. Studies predominantly conducted over the last two decades implicate that macrophage responses are also modulated by neuronal mediators such as neurotransmitters or neurotrophic factors. Here we summarize the current understanding of neuromediator-dependent interplay between macrophages and the nervous system.     

A successful twin pregnancy in a patient with HbE-β-thalassemia in western India

Improvements in medical facilities have helped a large number of clinically severe hemoglobin E (HbE)-β-thalassemia patients reach adulthood. Consequently, there is a new challenge, that of managing women with HbE-β-thalassemia during pregnancy. In particular, they have a high risk of abortion, preterm delivery, intrauterine growth restriction, and thromboembolism. A 27-year-old HbE-β-thalassemia patient on regular transfusion, who was splenectomized and heptatitis C (HCV)-positive, conceived for the first time without any infertility treatment. However, there was incomplete abortion with heavy bleeding at 3 months of gestation, which required bilateral uterine artery angiography. The angiogram showed the left uterine artery to be moderately hypertrophied. This was embolized with 300-500 micron polyvinyl alcohol (PVA) to stop the bleeding. Soon after, she conceived again with a twin pregnancy, and at 33.3 weeks of gestation, there was a normal delivery of twin girls without any postpartum hemorrhage or perineal tear. Both babies were given prematurity care. The mother and children were both normal up till the last follow-up 18 months after delivery, and both the girls are HbE heterozygous. Thorough monitoring of endocrine functions along with proper management of transfusions and iron overload can help in reducing the complications related to pregnancy in these patients.KEY WORDS: Hemoglobin E (HbE)-β-thalassemia, hydroxyurea, iron chelation, twin pregnancy     

Association of tumor necrosis factor-α gene promoter polymorphisms (-308G/A, -238G/A) with recurrent spontaneous abortion: a meta-analysis

Tumor necrosis factor-α (TNF-α) gene promoter polymorphisms (-308G/A, -238G/A) have been associated with increased recurrent spontaneous abortion (RSA) risk, but the results of published articles are controversial. Hence, a meta-analysis was performed to assess the effect of TNF-α -308G/A, -238G/A polymorphisms on RSA risk. Heterogeneity testing and sensitivity analysis were performed using RevMan 5.0 software. Publication bias was assessed by the funnel plot method and modified Egger's linear regression test. In 12 studies for the TNF-α -308G/A polymorphism, the summary odds ratio (OR) with the corresponding 95% confidence interval (95% CI) was 1.04 (95% CI: 0.86, 1.26) under a fixed-effect model in the overall population. In 5 studies for the TNF-α -238G/A polymorphism, the summary OR with the corresponding 95% CI was 1.11 (95% CI: 0.60, 2.03) under a random-effect model in the overall population. We could not identify the sources of heterogeneity for TNF-α -238G/A. In addition, no evidence of publication bias was detected. The results of this meta-analysis indicate that TNF-α -308G/A, -238G/A polymorphisms are not significantly associated with the risk of RSA in the overall population. However, more convincing evidence is required to draw a solid conclusion on the relation between the TNF-α -238G/A polymorphism and the risk of RSA.     

Genetic variability in the IL1RN gene and the balance between interleukin (IL)-1 receptor agonist and IL-1β in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a rapidly progressive interstitial lung disease of unknown aetiology. Interleukin (IL)-1β plays an important role in inflammation and has been associated with fibrotic remodelling. We investigated the balance between IL-1β and IL-1 receptor antagonist (IL-1Ra) in bronchoalveolar lavage fluid (BALF) and serum as well as the influence of genetic variability in the IL1B and IL1RN gene on disease susceptibility and cytokine levels. In 77 IPF patients and 349 healthy controls, single nucleotide polymorphisms (SNPs) in the IL1RN and IL1B genes were determined. Serum and BALF IL-1Ra and IL-1β levels were measured using a multiplex suspension bead array system and were correlated with genotypes. Both in serum and BALF a significantly decreased IL-1Ra/IL-1β ratio was found in IPF patients compared to healthy controls. In the IL1RN gene, one SNP was associated with both the susceptibility to IPF and reduced IL-1Ra/IL-1β ratios in BALF. Our results show that genetic variability in the IL1RN gene may play a role in the pathogenesis of IPF and that this role may be more important than thought until recently. The imbalance between IL-1Ra and IL-1β might contribute to a proinflammatory and pro-fibrotic environment in their lungs.     

A preliminary note on a “zone phenomenon” in bacteriostasis

Summary While testing the antibacterial action of quinine dihydrochloride on staphylococci, a zone of promotion of growth below and above which bacteriostasis occurred was observed.     

A(₂A) adenosine receptor (A(₂A)AR) as a therapeutic target in diabetic retinopathy

In diabetic retinopathy (DR), abnormalities in vascular and neuronal function are closely related to the local production of inflammatory mediators whose potential source is microglia. A_2A adenosine receptor (A_2AAR) has been shown to possess anti-inflammatory properties that have not been studied in DR. Here, we evaluate the role of A_2AAR and its underlying signaling in retinal complications associated with diabetes. Initial studies in wild-type mice revealed that the treatment with the A_2AAR agonist resulted in marked decreases in hyperglycemia-induced retinal cell death and tumor necrosis factor (TNF)-α release. To further assess the role of A_2AAR in DR, we studied the effects of A_2AAR ablation on diabetes-induced retinal abnormalities. Diabetic A_2AAR^−/− mice had significantly more terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive cells, TNF-α release, and intercellular adhesion molecule-1 expression compared with diabetic wild-type mice. To explore a potential mechanism by which A_2AAR signaling regulates inflammation in DR, we performed additional studies using microglial cells treated with Amadori-glycated albumin, a risk factor in diabetic disorders. The results showed that activation of A_2AAR attenuated Amadori-glycated albumin-induced TNF-α release in a cAMP/exchange protein directly activated by cAMP-dependent mechanism and significantly repressed the inflammatory cascade, C-Raf/extracellular signal-regulated kinase (ERK), in activated microglia. Collectively, this work provides pharmacological and genetic evidence for A_2AAR signaling as a control point of cell death in DR and suggests that the retinal protective effect of A_2AAR is mediated by abrogating the inflammatory response that occurs in microglia via interaction with C-Raf/ERK pathway.Diabetic retinopathy (DR) is the leading cause of blindness in the Western world and the most common complication of diabetes.^1,2 DR has been categorized as a vascular-neuroinflammatory disease. Early features of DR include signs of retinal inflammatory reactions, breakdown of the blood-retinal barrier function and loss of retinal neurons.^3–5 Under these conditions, normally quiescent microglial cells become activated.^6,7 Activated microglia release glutamate, reactive oxygen species, and proinflammatory mediators, such as tumor necrosis factor (TNF)-α.^8–10 The retinal expression of TNF-α has been reported to be associated with neuronal and endothelial cell death, hallmark features of the disease,^5,11 and inhibition of TNF-α has demonstrated beneficial effects in the prevention of early DR.¹² Thus, research on retinal microglia activation may provide insights into the pathogenesis of DR.¹³Adenosine has been proposed to modulate a variety of physiological responses.¹⁴ Under stress conditions, the local levels of extracellular adenosine are increased due to the increased need for energy supplied by ATP¹⁵ and the increased degradation of released ATP.¹⁶ The increased adenosine at inflamed sites can protect against cellular damage by activating A_2A adenosine receptor (A_2AAR), a Gs-coupled receptor.¹⁷ Treatment with an A_2AAR agonist blocked the inflammation and functional changes associated with diabetic nephropathy in wild-type diabetic mice, but not in the diabetic A_2AAR^{−/− mice}.¹⁸Recent efforts to understand how neurotoxic inflammatory cytokines are produced have shown that Ras/Raf/MEK/extracellular signal-regulated kinase (ERK) cascade is one of the attractive targets for intervention in human inflammatory-associated diseases, such as diabetes. However, this cascade does not operate alone, but rather interacts with other signaling systems, such as Gs-coupled receptor transducing pathway. Activation of this pathway results in accumulation of cAMP that interacts with the Ras/Raf/MEK/ERK kinase signaling to regulate cell functions.¹⁹Previously we demonstrated the anti-inflammatory effect of A_2AAR in acute retinal inflammation.²⁰ Currently, we seek to determine the contribution of A_2AAR in retinal protection against diabetes-induced retinal inflammation and injury. Moreover, we pursue to gain insight into the underlying signaling involved therein. Here, we report evidence that activation of A_2AAR plays a protective role in diabetes-induced retinal cell death by enhancing the anti-inflammatory signaling, including the interaction with C-Raf/ERK cascade. These findings suggest that A_2AAR agonists may be promising innovative agents in the treatment of diabetic retinopathy.