BACKGROUND & AIMS: The mammalian transcription factor LSF (CP2/LBP-1c) binds cellular promoters modulated by cell growth signals. We demonstrate here that LSF-DNA-binding activity is strikingly regulated by induction of cell growth in human peripheral T lymphocytes. Within 15 min of mitogenic stimulation of these cells, the level of LSF-DNA-binding activity increased by a factor of five. The level of LSF protein in the nucleus remained constant throughout this interval. However, a rapid decrease in the electrophoretic mobility of LSF, attributable to phosphorylation, correlated with the increase in DNA-binding activity. pp44 (ERK1) phosphorylated LSF in vitro on the same residue that was phosphorylated in vivo, specifically at amino acid position 291, as indicated by mutant analysis. As direct verification of the causal relationship between phosphorylation and DNA-binding activity, treatment in vitro of LSF with phosphatase both increased the electrophoretic mobility of the protein and decreased LSF-DNA-binding activity. This modulation of LSF-DNA-binding activity as T cells progress from a resting to a replicating state reveals that LSF activity is regulated during cell growth and suggests that LSF regulates growth-responsive promoters.

背景与目标： 哺乳动物转录因子LSF (CP2/LBP-1c) 结合由细胞生长信号调节的细胞启动子。我们在此证明，LSF-DNA结合活性通过诱导人外周血T淋巴细胞中的细胞生长而显着调节。在有丝分裂刺激这些细胞的15分钟内，lsf-dna结合活性水平增加了5倍。在整个间隔内，细胞核中LSF蛋白的水平保持恒定。然而，由于磷酸化，LSF的电泳迁移率迅速降低与DNA结合活性的增加有关。pp44 (ERK1) 在体内磷酸化的相同残基上体外磷酸化LSF，具体地在氨基酸位置291，如突变体分析所示。作为磷酸化与DNA结合活性之间因果关系的直接验证，用磷酸酶体外处理LSF既增加了蛋白质的电泳迁移率，又降低了LSF-DNA结合活性。随着T细胞从静止状态发展为复制状态，LSF-DNA结合活性的这种调节表明LSF活性在细胞生长过程中受到调节，并表明LSF调节生长反应性启动子。

BACKGROUND & AIMS: Thrombin activation requires assembly of a prothrombinase complex of activated coagulation factors on an anionic phospholipid surface, classically provided by activated platelets. We have previously shown that anionic phosphatidylserine is exposed by rat vascular smooth muscle cells (VSMCs) undergoing apoptosis after serum withdrawal. In this study, using a chromogenic assay, we have shown thrombin generation by apoptotic VSMCs expressing c-myc (VSMC-myc) with an area under the thrombin-generation curve (AUC) of 305 +/- 17 nmol x min/L and a peak thrombin (PT) of 154 +/- 9 nmol/L. The thrombin-generating potential of the apoptotic VSMC-myc cells was greater than that of unactivated platelets (P = .003 for AUC; P = .0002 for PT) and similar to calcium-ionophore activated platelets (AUC of 332 +/- 15 nmol x min/L, P = .3; PT of 172 +/- 8 nmol/L, P = .2). Thrombin activation was also seen with apoptotic human VSMCs (AUC of 211 +/- 8 nmol x min/L; PT of 103 +/- 4 nmol/L) and was inhibited by annexin V (P < .0001 for AUC and PT). VSMC-myc cells maintained in serum generated less thrombin than after serum withdrawal (P = .0002 for AUC and PT). VSMCs derived from human coronary atherosclerotic plaques that apoptose even in serum also generated thrombin (AUC of 260 +/- 2 nmol x min/L; PT of 128 +/- 4 nmol/L). We conclude that apoptotic VSMCs possess a significant thrombin-generating capacity secondary to phosphatidylserine exposure. Apoptotic cells within atherosclerotic plaques may allow local thrombin activation, thereby contributing to disease progression.

背景与目标： 凝血酶激活需要在阴离子磷脂表面上组装活化的凝血因子的凝血酶原复合物，通常由活化的血小板提供。我们以前已经表明，阴离子磷脂酰丝氨酸被大鼠血管平滑肌细胞 (VSMCs) 暴露，在血清戒断后发生凋亡。在这项研究中，使用显色测定法，我们已经显示表达c-myc (VSMC-myc) 的凋亡VSMC产生凝血酶，凝血酶产生曲线 (AUC) 下面积为305 +/- 17 nmol × min/L，凝血酶峰 (PT) 为154 +/- 9 nmol/L。凋亡的VSMC-myc细胞的凝血酶生成潜力大于未激活的血小板 (AUC P = .003; PT P = .0002)，与钙离子载体激活的血小板相似 (AUC为332 +/- 15 nmol x min/L，P = .3; PT为172 +/- 8 nmol/L，P = .2)。在凋亡的人VSMCs中也可以看到凝血酶活化 (AUC为211 +/- 8 nmol × min/L; PT为103 +/- 4 nmol/L)，并被膜联蛋白V抑制 (P < .0001 AUC和PT)。维持在血清中的VSMC-myc细胞产生的凝血酶少于血清戒断后 (对于AUC和PT，P = .0002)。来源于人冠状动脉粥样硬化斑块的VSMCs，即使在血清中凋亡也产生凝血酶 (AUC为260 +/- 2 nmol × min/L; PT为128 +/- 4 nmol/L)。我们得出的结论是，凋亡的VSMCs在磷脂酰丝氨酸暴露后具有显着的凝血酶生成能力。动脉粥样硬化斑块内的凋亡细胞可能会激活局部凝血酶，从而促进疾病进展。

BACKGROUND & AIMS: :There is an abundance of clinical applications using human umbilical cord blood (HUCB) as a source for stem cell populations. Other than haematopoietic progenitors, there are mesenchymal, endothelial stem cells and neuronal precursors, in varying quantities, that are found in human umbilical cord blood. These may be useful in diseases such as immune deficiency and autoimmune disorders. Considering issues of safety, availability, transplant methodology, rejection and side effects, it is contended that a therapeutic stem cell transplant, utilizing stem cells from HUCB, provides a reliable repository of early precursor cells that can be useful in a great number of diverse conditions. Drawbacks of relatively smaller quantities of mononucleated cells in one unit of cord blood can be mitigated by in-vitro expansion procedures, improved in-vivo signalling, and augmentation of the cellular milieu, while simultaneously choosing the appropriate transplantation site and technique for introduction of the stem cell graft.

背景与目标： : 使用人脐带血 (HUCB) 作为干细胞种群的来源有很多临床应用。除造血祖细胞外，在人脐带血中还发现了各种数量的间充质，内皮干细胞和神经元前体。这些可能在诸如免疫缺陷和自身免疫性疾病等疾病中有用。考虑到安全性，可用性，移植方法，排斥反应和副作用等问题，有人认为，利用HUCB干细胞的治疗性干细胞移植提供了可靠的早期前体细胞储存库，可用于多种多样的条件。可以通过体外扩增程序，改善体内信号传导和增加细胞环境，同时选择合适的移植部位和技术来引入脐带血，减轻脐带血中相对较少数量的单核细胞的缺点。干细胞移植物。

BACKGROUND & AIMS: :The mechanism by which T cells signal other T cells is not well defined. This was investigated by studying the ability of circulating T cells to induce the proliferation of autologous T cell clones. Peripheral blood T cells activated by cross-linking of the CD3/T cell receptor complex, which increased the expression of cell adhesion molecules LFA-1, LFA-3 and ICAM-1, induced the proliferation of autologous T cell clones. Irradiated antigen-activated peripheral blood T cells could also induce the proliferation of T cell clones which could not recognize that antigen. T-T cell activation required cell contact, was not major histocompatibility complex (MHC) restricted and was blocked by monoclonal antibodies directed against adhesion molecules CD2 and LFA-3 but was not blocked by antibody to class II MHC determinants. As CD2 is the natural ligand for LFA-3, increased expression of T cell surface adhesion molecules LFA-1, ICAM-1 and particularly LFA-3 during an inflammatory response may rapidly recruit T cells that are activated through the CD2 pathway. These results allow a simplified model to explain how relatively few antigen/MHC-specific T cells can recruit large numbers of non-antigen-specific T cells in the generation of an inflammatory response and postulates a novel role of the CD2 molecule in T cell immune function.

背景与目标： : T细胞向其他T细胞发出信号的机制尚不明确。通过研究循环T细胞诱导自体T细胞克隆增殖的能力进行了研究。通过CD3/T细胞受体复合物交联激活的外周血T细胞，增加细胞粘附分子LFA-1、LFA-3和ICAM-1的表达，诱导自体T细胞克隆增殖。辐照的抗原激活的外周血T细胞也可以诱导无法识别该抗原的T细胞克隆的增殖。T-t细胞活化需要细胞接触，不受主要组织相容性复合物 (MHC) 的限制，并被针对粘附分子CD2和LFA-3的单克隆抗体阻断，但未被针对II类MHC决定簇的抗体阻断。由于CD2是LFA-3的天然配体，因此在炎症反应期间LFA-1、ICAM-1并且特别是LFA-3的T细胞表面粘附分子的表达增加可以快速募集通过CD2途径激活的T细胞。这些结果允许一个简化的模型来解释相对较少的抗原/MHC特异性T细胞如何在炎症反应的产生中募集大量非抗原特异性T细胞，并假设CD2分子在T细胞免疫功能中的新作用。

BACKGROUND & AIMS: PURPOSE:To determine the effect of latanoprost on the expression of human matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in the trabecular meshwork (TM). METHODS:Total RNA was isolated, and qualitative RT-PCR was performed to detect the mRNA of MMPs and TIMPs in human TM tissue and explant cultures of TM endothelial cells. Cultures of TM cells were treated with vehicle control or latanoprost acid for 24 hours. Real-time RT-PCR of cell cultures from five different donors was performed to determine relative changes in expression. GAPDH served as an endogenous control. RESULTS:The mRNA of MMP-1, -2, -3, -11, -12, -14, -15, -16, -17, -19, and -24 and of TIMP-1 to -4 was present in TM tissue and cultures of TM cells. MMP-9 was not found. In control TM endothelial cells, the relative expression of MMP mRNA were MMP-2 and -14 > MMP-16, -19, and -24 > MMP-15 > MMP-11 and -17 > MMP-1 and -3 > MMP-12. The relative expressions of TIMP mRNA were TIMP-1 > TIMP-2 and -3 > TIMP-4. Latanoprost increased MMP-1 (in four of five cultures), MMP-3 (in four of five cultures), MMP-17 (in three of five cultures), MMP-24 (in all five cultures), TIMP-2, -3, and -4 expression (in three of five cultures); MMP-11 and -15 were downregulated. CONCLUSIONS:Contrary to the expected result, latanoprost seems to have a significant effect on TM cells. The transcription of the genes for MMP-1, -3, -17, and -24 is increased by latanoprost treatment. TIMP-2, -3, and -4 are also upregulated. The upregulation of these TIMPs may compensate for the increase of those MMPs. The absence of MMP-9 and concurrent upregulation of a greater number of TIMPs may explain the limited effect of latanoprost on TM outflow.

背景与目标：

BACKGROUND & AIMS: Cardiac troponin T (cTnT) and troponin I (cTnI) have been suggested as new, more specific markers of myocardial cellular damage. The objective of this study was to examine how the distributions of cTnI and cTnT were affected in postinfarction left ventricular remodeled (LVR) myocardium. At 2 months postinfarct in a porcine heart failure model, both Western blot and biochemical assay analyses were performed on left ventricular myocardium remote from the infarct zone in ligation animals (n = 8). Results were compared with data from the left ventricular myocardium from similar sized healthy (control) pigs (n = 7). Autoradiograms from Western blot analysis showed that the protein mass for cTnI and cTnT in LVR hearts decreased 80% (P < 0.001) and 40% (P < 0.02), respectively, when compared with nondiseased tissue. Similarly, the concentrations for cTnI and cTnT in LVR hearts decreased 42% (P < 0.05) and 70% (P < 0.001), respectively, compared with nondiseased normal tissue. The clinical assumption is that the appearance of cTnI and cTnT in the blood is proportional to chronic loss of cTnI and cTnT from injured myocardium associated with left ventricular remodeling.

背景与目标： 心肌肌钙蛋白T (cTnT) 和肌钙蛋白I (cTnI) 已被认为是新的，更特异的心肌细胞损伤标志物。这项研究的目的是研究梗死后左心室重塑 (LVR) 心肌中cTnI和cTnT的分布如何受到影响。在猪心力衰竭模型中，在梗塞后2个月，对结扎动物 (n = 8) 远离梗塞区的左心室心肌进行了Western印迹和生化测定分析。将结果与类似大小的健康 (对照) 猪 (n = 7) 的左心室心肌数据进行了比较。来自Western blot分析的放射自显影图显示，与未患病组织相比，LVR心脏中cTnI和cTnT的蛋白质质量分别降低了80% (P < 0.001) 和40% (P <0.02)。同样，与未患病的正常组织相比，LVR心脏中cTnI和cTnT的浓度分别降低了42% (P < 0.05) 和70% (P <0.001)。临床假设是血液中cTnI和cTnT的出现与与左心室重构相关的受损心肌的cTnI和cTnT的慢性损失成正比。

BACKGROUND & AIMS: :Cochlear marginal cells and vestibular dark cells transport potassium into the inner ear endolymph, a potassium-rich fluid, the homeostasis of which is essential for hearing and balance. We have formulated an integrated mathematical model of ion transport across these epithelia that incorporates the biophysical properties of the major ion transporters and channels located in the apical and basolateral membranes of the constituent cells. The model is constructed for both open- and short-circuit situations to test the extremes of functional capacity of the epithelium and predicts the steady-state voltages, ion concentrations, and transepithelial currents as a function of various transporter and channel densities. We validate the model by establishing that the cells are capable of vectorial ion transport consistent with several experimental measurements. The model indicates that cochlear marginal cells do not make a significant direct contribution to the endocochlear potential and illustrates how changes to the activity of specific transport proteins lead to reduced K(+) flux across the marginal and dark cell layers. In particular, we investigate the mechanisms of loop diuretic ototoxicity and diseases with hearing loss in which K(+) and Cl(-) transport are compromised, such as Jervell and Lange-Nielsen syndrome and Bartter syndrome, type IV, respectively. Such simulations demonstrate the utility of compartmental modeling in investigating the role of ion homeostasis in inner ear physiology and pathology.

背景与目标： : 耳蜗边缘细胞和前庭暗细胞将钾输送到内耳内淋巴中，内淋巴是一种富含钾的液体，其稳态对于听力和平衡至关重要。我们已经建立了跨这些上皮细胞的离子转运的综合数学模型，该模型结合了位于组成细胞的顶膜和基底外侧膜中的主要离子转运蛋白和通道的生物物理特性。该模型是针对开路和短路情况构建的，以测试上皮功能能力的极限，并预测稳态电压，离子浓度和跨上皮电流与各种转运蛋白和通道密度的关系。我们通过建立细胞能够与几种实验测量一致的矢量离子传输来验证模型。该模型表明，耳蜗边缘细胞对耳蜗内电位没有明显的直接贡献，并说明了特定转运蛋白活性的变化如何导致边缘细胞层和暗细胞层的K () 通量减少。特别是，我们研究了环利尿剂耳毒性的机制以及K () 和Cl(-) 转运受损的听力损失疾病，例如Jervell和Lange-Nielsen综合征以及IV型Bartter综合征。此类模拟证明了隔室建模在研究离子稳态在内耳生理和病理学中的作用方面的实用性。

BACKGROUND & AIMS: The involvement of antigen-specific T cells in the pathogenesis of collagen diseases is still controversial. The final stages of collagen diseases are usually characterized by the dominance of inflammation. Therefore, antigen non-specific factors, such as inflammatory cytokines, probably play an important role in this process. On the other hand, the methods available to analyze the antigen-specific aspects of the immune response are still limited. Here we review our novel system of T cell clonality analysis based on the idea that activated antigen-specific T cells should form accumulating clones among the lymphocyte population. Using this method, dynamic changes of clonal accumulation of T cells could be evaluated during antigenic stimulation in vivo and in vitro. The significance of antigen-specific T cell clones in collagen diseases is discussed using data obtained from patients with rheumatoid arthritis and systemic lupus erythematosus.

背景与目标： 抗原特异性T细胞参与胶原疾病的发病机理仍存在争议。胶原蛋白疾病的最后阶段通常以炎症为主。因此，抗原非特异性因子 (如炎性细胞因子) 可能在这一过程中起重要作用。另一方面，用于分析免疫应答的抗原特异性方面的方法仍然有限。在这里，我们基于激活的抗原特异性T细胞应在淋巴细胞群体中形成累积克隆的想法，回顾了我们的新型T细胞克隆分析系统。使用该方法，可以在体内和体外评估抗原刺激过程中T细胞克隆积累的动态变化。使用类风湿关节炎和系统性红斑狼疮患者获得的数据讨论了抗原特异性T细胞克隆在胶原疾病中的意义。

BACKGROUND & AIMS: :Mast cells are known to be effector cells in various inflammatory reactions, but their role in appendicitis is unclear. The present study was undertaken to investigate the extent of mast cell involvement in appendicitis and evaluate their possible role. A total of 150 appendices including normal and inflamed appendices, were assessed for their histological changes and density of neutrophil, lymphocyte and eosinophil infiltration. The mast cells were counted in 1% toluidine blue-stained sections. It was found that eosinophil counts in all the layers were significantly low in normal appendices (P<0.01) and in chronic appendicitis (P<0.1) as compared to acute appendicitis. Mast cell counts were lowest in normal appendices, significantly higher in acute appendicitis (P<0.01) and highest in chronic appendicitis (P<0.001). Obstruction due to faecoliths or parasites were seen in only 20.1% and 2.1% of the inflamed appendices respectively. Hence a Type I hypersensitivity reaction with release of mediators by mast cells might be another triggering factor for the sequence of events leading to appendicitis.

背景与目标： 肥大细胞是各种炎症反应中的效应细胞，但它们在阑尾炎中的作用尚不清楚。本研究旨在研究肥大细胞在阑尾炎中的参与程度并评估其可能的作用。共评估了150个阑尾 (包括正常和发炎的阑尾) 的组织学变化以及中性粒细胞，淋巴细胞和嗜酸性粒细胞浸润的密度。在1% 甲苯胺蓝染色切片中计数肥大细胞。发现与急性阑尾炎相比，正常阑尾 (P<0.01) 和慢性阑尾炎 (P<0.1) 中所有层的嗜酸性粒细胞计数均显着降低。肥大细胞计数在正常阑尾中最低，在急性阑尾炎中显着较高 (P<0.01)，在慢性阑尾炎中最高 (P<0.001)。仅在发炎的20.1% 和2.1% 的阑尾中分别看到由粪便石或寄生虫引起的阻塞。因此，肥大细胞释放介质的I型超敏反应可能是导致阑尾炎事件序列的另一个触发因素。

BACKGROUND & AIMS: The abdomen of adult Drosophila, like that of other insects, is formed by a continuous epithelium spanning several segments. Each segment is subdivided into an anterior (A) and posterior (P) compartment, distinguished by activity of the selector gene engrailed (en) in P but not A compartment cells. Here we provide evidence that Hedgehog (Hh), a protein secreted by P compartment cells, spreads into each A compartment across the anterior and the posterior boundaries to form opposing concentration gradients that organize cell pattern and polarity. We find that anteriorly and posteriorly situated cells within the A compartment respond in distinct ways to Hhthey express different combinations of genes and form different cell types. They also form polarised structures that, in the anterior part, point down the Hh gradient and, in the posterior part, point up the gradient - therefore all structures point posteriorly. Finally, we show that ectopic Hh can induce cells in the middle of each A compartment to activate en. Where this happens, A compartment cells are transformed into an ectopic P compartment and reorganise pattern and polarity both within and around the transformed tissue. Many of these results are unexpected and lead us to reassess the role of gradients and compartments in patterning insect segments.

背景与目标： 与其他昆虫一样，成年果蝇的腹部是由横跨多个节段的连续上皮形成的。每个节段都分为前 (A) 和后 (P) 隔室，其特征是在P细胞中包含 (en) 的选择基因的活性，而不是隔室细胞。在这里，我们提供的证据表明，刺猬 (Hh) 是一种由P室细胞分泌的蛋白质，通过前后边界扩散到每个a室中，形成相反的浓度梯度，从而组织细胞模式和极性。我们发现，位于A区室前后的细胞以不同的方式对hh做出反应，它们表达不同的基因组合并形成不同的细胞类型。它们还形成极化结构，在前部指向Hh梯度，在后部指向梯度，因此所有结构都指向后部。最后，我们证明异位Hh可以诱导每个A室中间的细胞激活en。在发生这种情况的情况下，一个隔室细胞被转化为异位的P隔室，并在转化的组织内部和周围重组模式和极性。这些结果中有许多是出乎意料的，使我们重新评估了梯度和区室在昆虫节段构图中的作用。

BACKGROUND & AIMS: CONTEXT:In animal models, estrogen inhibits atherogenesis by inhibiting many of the early steps of atherosclerotic plaque formation. However, the lack of cardioprotective effect by postmenopausal hormone replacement therapy and possible increase in cardiovascular events observed during the first year after the initiation of hormone replacement therapy may suggest that once the plaque is formed, estrogen may have additional effects that may counteract its beneficial outcomes. Indeed, the effect of estrogen on plaque stability has not been identified. OBJECTIVE:We hypothesized that 17beta-estradiol (E2) may cause increased apoptosis in human coronary artery endothelial cells (HCAECs). This effect would explain an adverse effect on plaque stability in vivo. INTERVENTION(S) AND MAIN OUTCOME MEASURE(S):The effect of E2 on apoptosis, cell proliferation, and expression of proapoptotic molecules Fas and Fas ligand (FasL) in cultured HCAECs was evaluated. RESULTS:HCAECs in culture treated with E2 showed an increase in DNA strand breaks and nuclear fragmentation indicative of apoptosis. E2 treatment also induced a significant concentration-dependent increase in Fas mRNA and protein expressions in HCAECs. Moreover, the expression of FasL mRNA and secretion of FasL protein by HCAECs were enhanced in response to E2 treatments. CONCLUSIONS:E2 increases the apoptosis in cultured HCAECs. Enhanced Fas and FasL expressions in response to E2 suggest that activation of the Fas/FasL pathway may be a mediator of the proapoptotic effects of E2 in these cells.

背景与目标：

BACKGROUND & AIMS: Interleukin-1beta (IL-1beta) is closely involved in liver disorders. IL-1beta produces nitric oxide (NO) in vascular smooth muscle cells and relaxes vascular smooth muscle via cyclic guanosine 3',5'-monophosphate (cGMP). In this study, we evaluated the relaxing effect of IL-1beta on cultured Ito cells. Ito cells were isolated from the livers of male Wistar rats and cultured for 24 hours. Immunolocalization of inducible nitric oxide synthase (iNOS) and cGMP and intensity of fluorescence of cGMP were examined using a confocal laser microscope. Ito cells were treated with 0, 200, and 1,000 pmol/L IL-1beta, and the intracellular cGMP concentration was measured after 12 hours. Moreover, Ito cells treated with 200 and 1,000 pmol/L IL-1beta and not treated with IL-1beta were observed over 12 hours, and the area of the same Ito cell was compared before and after the addition of IL-1beta. Next, effects of N(G)-monomethyl-L-arginine (L-NMMA) and S-nitroso-N-acetyl-DL-penicillamine (SNAP) on Ito cell relaxation by IL-1beta treatment were examined. In Ito cells, immunofluorescence of iNOS was observed, and fluorescent intensity of cGMP increased after addition of IL-1beta. Intracellular cGMP concentration increased dose-dependently after addition of IL-1beta. Cell area significantly increased in the IL-1beta-treated group compared with the untreated group. Relaxation of Ito cells by IL-1beta treatment was inhibited by L-NMMA in a dose-dependent manner, but was enhanced by SNAP. These results indicate that IL-1beta produces NO in cultured Ito cells and relaxes the cells via cGMP.

背景与目标： Interleukin-1beta (IL-1beta) 与肝脏疾病密切相关。IL-1beta在血管平滑肌细胞中产生一氧化氮 (NO)，并通过环鸟苷3 '，5'-单磷酸 (cGMP) 松弛血管平滑肌。在这项研究中，我们评估了IL-1beta对培养的Ito细胞的松弛作用。从雄性Wistar大鼠的肝脏中分离Ito细胞，并培养24小时。使用共聚焦激光显微镜检查诱导型一氧化氮合酶 (iNOS) 和cGMP的免疫定位以及cGMP的荧光强度。Ito细胞用0、200和1,000 pmol/L IL-1beta处理，12小时后测定细胞内cGMP浓度。此外，在12小时内观察到用200和1,000 pmol/L IL-1beta处理和不用IL-1beta处理的Ito细胞，并比较在添加IL-1beta前后相同Ito细胞的面积。接下来，通过IL-1beta处理检查了N(G)-单甲基-L-精氨酸 (L-NMMA) 和S-亚硝基-N-乙酰基-DL-青霉胺 (SNAP) 对Ito细胞松弛的影响。在Ito细胞中，观察到iNOS的免疫荧光，加入IL-1beta后cGMP的荧光强度增加。加入IL-1beta后，细胞内cGMP浓度呈剂量依赖性增加。与未处理组相比，IL-1beta-treated组的细胞面积显着增加。IL-1beta处理对Ito细胞的松弛以剂量依赖性方式被l-nmma抑制，但被SNAP增强。这些结果表明，IL-1beta在培养的Ito细胞中产生NO，并通过cGMP使细胞松弛。

BACKGROUND & AIMS: :Cadmium is suspected to exert its toxic action on cells through oxidative damage. However, the transition metal is unable to directly generate reactive oxygen species (ROS) via redox reactions with molecular oxygen in a biological environment. Here, we show that bright yellow-2 (BY-2) tobacco cells exposed to millimolar concentrations of CdCl(2) developed cell death within 2-3 h. The death process was preceded by two successive waves of ROS differing in their nature and subcellular localization. Firstly, these consisted in the transient NADPH oxidase-dependent accumulation of H(2)O(2) followed by the accumulation of O(2) (-*) in mitochondria. A third wave of ROS consisting in fatty acid hydroperoxide accumulation was concomitant with cell death. Accumulation of H(2)O(2) was preceded by an increase in cytosolic free calcium concentration originating from internal pools that was essential to activate the NADPH oxidase. The cell line gp3, impaired in NADPH oxidase activity, and that was unable to accumulate H(2)O(2) in response to Cd(2+), was nevertheless poisoned by the metal. Therefore, this first wave of ROS was not sufficient to trigger all the cadmium-dependent deleterious effects. However, we show that the accumulation of O(2) (-*) of mitochondrial origin and membrane peroxidation are key players in Cd(2+)-induced cell death.

背景与目标： : 镉被怀疑通过氧化损伤对细胞产生毒性作用。然而，在生物环境中，过渡金属无法通过与分子氧的氧化还原反应直接产生活性氧 (ROS)。在这里，我们显示暴露于毫摩尔浓度的CdCl(2) 的亮黄色2 (BY-2) 烟草细胞在2-3小时内发生细胞死亡。死亡过程之前是连续两波ROS，其性质和亚细胞定位不同。首先，这些因素包括H(2)O(2) 的瞬时NADPH氧化酶依赖性积累，然后是线粒体中O(2) (-*) 的积累。由脂肪酸氢过氧化物积累组成的第三波ROS伴随细胞死亡。H(2)O(2) 的积累之前，来自内部池的胞质游离钙浓度增加，这对于激活NADPH氧化酶至关重要。细胞系gp3的NADPH氧化酶活性受损，并且无法响应Cd(2) 积累H(2)O(2)，但仍被金属中毒。因此，第一波ROS不足以触发所有依赖镉的有害作用。然而，我们表明线粒体来源的O(2) (-*) 的积累和膜过氧化是Cd(2) 诱导的细胞死亡的关键因素。

BACKGROUND & AIMS: CD4+ anti-tumor T cells reactive with rat adenocarcinoma 13762 kill tumor in vitro and cause regression of tumor in vivo. The role of various host immune cells in CD4+ T-cell-mediated tumor elimination in vivo was investigated by adoptive transfer of anti-tumor T cell clones to recipients that were selectively depleted of individual immune cell types. By these means, macrophages and NK cells were found to be required for tumor killing. Depletion of host CD4+ T cells, CD8+ T cells, or neutrophils was without effect on tumor elimination by anti-tumor T cells. An essential role for antigen receptor-negative NK cells is likely dependent upon secretion of IFN-gamma from NK cells since treatment of tumor recipients with anti-IFN-gamma antibody prior to adoptive transfer and tumor challenge abrogated T cell killing, resulting in progressive tumor growth. Viability of adenocarcinoma 13762 or anti-tumor T cells was unaffected by treatment with either IFN-gamma or anti-IFN-gamma antibody in vitro, but cell surface MHC class II expression was induced in tumor cells by exposure to IFN-gamma. In addition, tumor cells were isolated from tumor-bearing animals by absorption using anti-MHC class II antibody, demonstrating that 13762 tumor expresses cell surface MHC class II antigens in situ. However, if hosts were depleted of NK cells before tumor challenge, MHC class II+ tumor was not recovered. Collectively these results suggest that adenocarcinoma 13762 is eliminated by MHC class II-restricted CD4+ T cells by direct tumor killing.

背景与目标： 与大鼠腺癌反应的CD4 + 抗肿瘤T细胞13762在体外杀伤肿瘤并在体内引起肿瘤的消退。通过将抗肿瘤T细胞克隆过继转移到选择性耗尽个体免疫细胞类型的受体，研究了各种宿主免疫细胞在体内CD4 T细胞介导的肿瘤消除中的作用。通过这些方法，发现巨噬细胞和NK细胞是杀死肿瘤所必需的。宿主CD4 T细胞，CD8 T细胞或中性粒细胞的耗竭对抗肿瘤T细胞消除肿瘤没有影响。抗原受体阴性NK细胞的重要作用可能取决于NK细胞中IFN-γ 的分泌，因为在过继转移和肿瘤挑战之前用抗IFN-γ 抗体治疗肿瘤接受者消除了T细胞杀伤，导致进行性肿瘤生长。腺癌13762或抗肿瘤T细胞的活力在体外不受IFN-γ 或抗IFN-γ 抗体治疗的影响，但细胞表面mhcii类表达通过暴露于IFN-γ 在肿瘤细胞中诱导。此外，通过使用抗MHC II类抗体吸收从荷瘤动物中分离肿瘤细胞，证明13762肿瘤原位表达细胞表面MHC II类抗原。但是，如果宿主在肿瘤激发之前耗尽了NK细胞，则MHC II类肿瘤将无法恢复。这些结果共同表明，通过直接杀伤肿瘤，MHC II类限制性CD4 T细胞消除了腺癌13762。

BACKGROUND & AIMS: The thymic microenvironment plays a key role in the intrathymic T-cell differentiation. It is composed of a tridimensional network of epithelial cells whose physiology is controlled by extrinsic circuits such as neuroendocrine axes. Herein we show that the expression of extracellular matrix ligands and receptor by cultured thymic epithelial cells is upregulated by prolactin (PRL) and growth hormone (GH), the latter apparently occurring via insulin-like growth factor I (IGF-I). Thymocyte release from the lymphoepithelial complexes, thymic nurse cells, as well as the reconstitution of these complexes are enhanced by PRL, GH or IGF-I. Treatment of a mouse thymic epithelial cell line with these hormones induced an increase in thymocyte adhesion, an effect significantly prevented in the presence of antibodies to fibronectin, laminin or respective receptors VLA-5 and VLA-6. Our data suggest that the in vitro changes in thymocyte/thymic epithelial cell interactions induced by pituitary hormones are partially mediated by the enhancement of extracellular matrix ligands and receptors.

背景与目标： 胸腺微环境在胸腺内T细胞分化中起关键作用。它由上皮细胞的三维网络组成，其生理受外部回路 (例如神经内分泌轴) 控制。在本文中，我们显示培养的胸腺上皮细胞的细胞外基质配体和受体的表达被催乳素 (PRL) 和生长激素 (GH) 上调，后者显然通过胰岛素样生长因子I (igf-i) 发生。PRL，GH或igf-i增强了从淋巴上皮复合物，胸腺护士细胞的胸腺细胞释放以及这些复合物的重建。用这些激素处理小鼠胸腺上皮细胞系诱导胸腺细胞粘附的增加，在存在针对纤连蛋白，层粘连蛋白或相应受体VLA-5和VLA-6的抗体的情况下，这种作用被显着阻止。我们的数据表明，垂体激素诱导的胸腺细胞/胸腺上皮细胞相互作用的体外变化部分是由细胞外基质配体和受体的增强介导的。