白细胞介素1与缺血性脑损伤

近年来研究发现,白细胞介素１（ＩＬ－１）在缺血后的脑内迅速增加,体内注射ＩＬ－１β可增在后脑梗塞灶体积、脑水肿程度及神经元死亡,减少实验动物脑缺血后存活时间。脑室内注射ＩＬ－１抑制剂及受体拮抗剂后缺血性脑损伤显著减轻,表明ＩＬ－１可能为缺轿性脑损伤的重要介质。     

IL—1β,IL—lra对戊四氮致痫大鼠行为及皮层,海马脑电的 …

目的：了解白细胞介素１β（ＩＬ－１β）在癫痫发作中的作用。方法：采用记录脑图（ＥＥＧ）同时观察行为的方法,观察ＩＬ－１β和ＩＬ－１受体拮抗剂（ＩＬ－１ｒａ）测脑室注射对戊四氮（ＰＴＺ）致痫大鼠和皮层、海马ＥＥＧ的影响。结果：ＩＬ－１β能明显缩短ＰＴＺ致大鼠急性惊厥发作及痫波发放的潜伏期,增加痫波的发放频率。ＩＬ－１ｒａ能减少急性惊厥痫波放频率,对急性惊厥发主痫波发放的潜伏期和惊厥发作强度无明显影响     

白细胞介素1家族新成员──IL－1Ra

白细胞介素１家族新成员──ＩＬ－１Ｒａ黄仕和秦椿华（卫生部武汉生物制品研究所,武汉４３００６０）（同济医科大学工业毒理研究室,武汉４３００３０）关键词ＩＬ－１Ｒａ以前认为,ＩＬ－１分为ＩＬ－１α和ＩＬ－１β两型,但Ａｒｅｎｄ等（１９８５）又发现了ＩＬ...     

白细胞介素—1β对醋氨酚诱导的小鼠肝损伤具有保护作用

在醋氨酚诱导的小鼠肝损伤模型上观察到５００００Ｕ／ｋｇ的白细胞介素－１β（ＩＬ－１β）,分别提前１,６和１２ｈ腹腔注射,可不同程度地降低ＧＰＴ和ＧＯＴ漏出,其中以提前１２ｈ的效果最强,而在给予醋氨酚之后１ｈ再注射此素则无效。在提前１２ｈ这一时间点观察不同剂量（１００００,３００００,５０００Ｕ／ｋｇ）ＩＬ－１β作用的结果表明,ＩＬ－１β抑制醋氨酚诱导的转氨酶漏出呈一定的剂量－效应关系,这三个剂量还     

白细胞介素－1β对新生大鼠胰岛素分泌的作用及其机制分析

本实验采用分离培养的新生大鼠胰岛，观察了白细胞介素１β（ＩＬ－１β）和Ｎ￣Ｇ－甲基－Ｌ－精氨酸（ＮＭＭＡ，ＮＯ合成酶的竞争性阻断剂）对胰岛素分泌及对胰岛中ｃＧＭＰ水平和亚硝酸盐浓度的影响。结果如下：（１）ＩＬ－１β（５、１０、２０Ｕ／ｍｌ）能抑制基础的和由葡萄糖（２０ｍｍｏｌ／Ｌ）刺激的胰岛素分泌。ＩＬ－１β对葡萄糖刺激的胰岛素分泌的抑制作用呈明显的量效关系，抑制率分别为５３．％，６０．５％和７０．７％。（２）ＮＭＭＡ（０．５ｍｍｏｌ／Ｌ）能阻断ＩＬ－１β对葡萄糖刺激的胰岛素分泌的抑制作用。（３）ＩＬ－１β能增加胰岛内ｃＧＭＰ水平和亚硝酸盐浓度，而ＮＭＭＡ能阻断这一效应。以上结果表明，ＩＬ－１β能抑制新生大鼠胰岛β细胞的功能，这一作用可能是通过ＮＯ实现的。     

胆囊收缩素对IL－1β损伤的胰岛β细胞功能的保护作用及其机制分析

本实验在分离培养的新生大鼠胰岛上,观察了胆囊收缩素（ＣＣＫ－８）对白细胞介素－１β（ＩＬ—１β）损伤的胰岛β细胞功能的影响。并就其机制进行初步分析。结果表明：（１）ＩＬ—１β（５,１０,２０Ｕ／ｍｌ）能抑制葡萄糖（２０ｍｍｏｌ／Ｌ）刺激的胰岛素分泌,其抑制作用具有量效关系,抑制率分别为５３．４％,６０．５％和７０．７％。（２）ＣＣＫ－８对ＩＬ－１损伤的胰岛β细胞的功能具有保护作用。预防性地给予ＣＣＫ－８（１０￣（－１０）,１０￣（－９）,１０￣（－８）,１０￣（－７）ｍｏｌ／Ｌ）能防止ＩＬ－１β对葡萄糖刺激的胰岛素分泌的抑制作用。治疗性地给予ＣＣＫ－８也能恢复胰岛对葡萄糖刺激的胰岛素分泌的能力。（３）ＣＣＫ　Ａ型受体阻断剂Ｌ３６４７１８（１０ｎｍｏｌ／Ｌ）能阻断ＣＣＫ－８的保护作用,表明这一作用可能是通过ＣＣＫ受体实现的。（４）ＩＬ－１β抑制胰岛素分泌的同时,能升高胰岛组织内ｃＧＭＰ水平,而ＣＣＫ－８能阻止ＩＬ－１引起的ｃＧＭＰ水平的升高。     

胆囊收缩素对IL—1β损伤的胰岛β细胞功能的保护作用及其…

本实验在分离培养的新生在鼠胰岛上,观察了胆囊收缩素（ＣＣＫ－８）对白细胞介素－１β（ＩＬ－１β）损伤的胰β细胞功能的影响。并就其机制进行初步分析,结果表明：（１）ＩＬ－１β（５,１０,２０Ｕ／ｍｌ）能抑制葡萄糖（２０ｍｍｏｌ／Ｌ）刺激的胰岛素分泌其抑制作用具有量效关系,抑制率分别为５３．４％,６０．５％和７０．７％。（２）ＣＣＫ－８对ＩＬ－１损伤的胰岛β细胞的功能具有保护作用。预防性地给予ＣＣＫ－     

脑啡肽对大鼠海马神经细胞IL-6基因表达的影响

本文研究了大鼠海马内微量注射甲硫－脑啡肽（Ｍ－ＥＮＫ）对海马细胞的白细胞介素－６（Ｉｎｔｅｒｌｅｕｋｉｎ－６,ＩＬ－６）基因表达的影响。大鼠双侧海马内微量注射细菌内毒素脂多糖各１μｌ（ＬＰＳ,浓度：５０ｎｇ／ｍｌ）,于９０ｍｉｎ后用原位杂交技术检测到海马结构ＩＬ－６的基因表达,以齿状回颗粒细胞层显著。当海马内预先注射Ｍ－ＥＮＫ（每侧１μｌ,浓度：１０μｇ／μｌ）,３０ｍｉｎ后再给予脂多糖则未见ＩＬ－６基因表达。结果表明Ｍ－ＥＮＫ及ＬＰＳ可影响脑内ＩＬ－６的基因表达,在中枢调节机体免疫功能中,ＩＬ－６可能具有重要作用。     

白细胞介素1与惊厥性脑损伤

白细胞介素1（IL－1）是重要的神经免疫介质。研究发现,惊厥后白细胞介素1β（IL－1β）,内源性白细胞介素1受体拮抗剂（IL－1ra)在脑内迅速增加,体内注射IL－1β可加重惊厥及神经元的损伤,而抑制β的作用,则惊厥及神经元损伤明显减轻,本文就近年来的研究进展,简要概括IL－1与惊厥性脑损伤及其神经保护作用的关系,IL－1在惊厥引起的脑损伤过程中的作用机制。     

α-黑色素细胞刺激素对白细胞介素-1β发热的解热机理研究

本研究观察了α－黑色素细胞刺激素（α－ＭＳＨ）对家兔白细胞介素－１β（ＩＬ－１β）发热效应及下丘脑组织腺苷环－磷酸（ｃＡＭＰ）含量的影响;同时观察了下丘本外培养过程中,α－ＭＳＨ对ＩＬ－１β刺激下丘脑释放ｃＡＭＰ的影响。结果显示：α－ＭＳＨ能显著降低ＩＬ－１β引起的体温升高（Ｐ〈０．０５）;同时抑制下丘脑组织ｃＡＭＰ含量的增高（Ｐ〈０．０１）。ＩＬ－１β与下丘脑组织培养,其上清液的ｃＡＭＰ含量明显     

Acid-dependent Interleukin-1 (IL-1) Cleavage Limits Available Pro-IL-1β for Caspase-1 Cleavage

Noncommunicable diseases such as cardiovascular disease (stroke and heart attack), cancer, chronic respiratory disease, and diabetes are a leading cause of death and disability worldwide and are worsened by inflammation. IL-1 is a driver of inflammation and implicated in many noncommunicable diseases. Acidosis is also a key feature of the inflammatory microenvironment; therefore it is vital to explore IL-1 signaling under acidic conditions. A HEK-IL-1 reporter assay and brain endothelial cell line were used to explore activity of mature IL-1α and IL-1β at pH 7.4 and pH 6.2, an acidic pH that can be reached under inflammatory or ischemic conditions, alongside cathepsin D-cleaved 20-kDa IL-1β produced under acidic conditions. We report that mature IL-1 signaling at IL-1 receptor type 1 (IL-1R1) is maintained at pH 6.2, but the activity of the decoy receptor, IL-1R2, is reduced. Additionally, cathepsin D-cleaved 20-kDa IL-1β was minimally active at IL-1R1 and was not further cleaved to highly active 17-kDa IL-1β. Therefore formation of the 20-kDa form of IL-1β may prevent the generation of mature bioactive IL-1β and thus may limit inflammation.     

促炎因子在心脏修复中的作用

肿 瘤 坏死 因 子 TN F)、白介 素 -1(IL-1)、白 介 素 -2(IL-2)以 及 白介 素 -6(IL-6)等 分子 ,叫 作 促 炎细 胞 因 (子 .一 般 认为 它 们不 属于 免 疫系 统,而 只是 与 组织 炎症 的起 始 有关 .促 炎因 子在 心 脏中 也 有表 达,它 的短 期表 达可 以 帮助 心 脏适 应外 界 压力 的损 伤 ,而其 长期 的 表达 却会 引 起明 显的 心 脏代 谢失 常 .主要 就 促炎 因子 在心 脏中 的 作用 作 一综 述 .     

人白细胞介素－2的两个部分拮抗剂

通过定点诱变技术得到6个生物活性剧烈下降的人白细胞介素-2(IL-2)突变体,其中两个突变体即15Val-IL-2和126Asp-IL-2可以在一定浓度范围内使IL-2的生物效应降低.在对高亲和力IL-2受体(IL-2R)的竞争抑制实验中,15Val-IL-2和126Asp-IL-2又表现了一定的竞争能力.这些结果表明15Val-IL-2和126Asp-IL-2的部分拮抗天然IL-2的作用.结合IL-2二级结构分析及对IL-2与IL-2R相互作用的已有认识,可认为15Val-IL-2和126Asp-IL-2的部分拮抗作用产生的原因在于替换残基在空间上对IL-2与IL-2R βγ亚基结合微环境的轻微扰动,干扰了IL-2有关残基与IL-2R βγ亚基的结合,但尚不能完全阻止其与IL-2R βγ亚基的结合.     

Complement Component C5a Primes Retinal Pigment Epithelial Cells for Inflammasome Activation by Lipofuscin-mediated Photooxidative Damage

Complement activation, oxidative damage, and activation of the NLRP3 inflammasome have been implicated in retinal pigment epithelium (RPE) pathology in age-related macular degeneration (AMD). Following priming of RPE cells, the NLRP3 inflammasome can be activated by various stimuli such as lipofuscin-mediated photooxidative damage to lysosomal membranes. We investigated whether products of complement activation are capable of providing the priming signal for inflammasome activation in RPE cells. We found that incubation of primary human RPE cells and ARPE-19 cells with complement-competent human serum resulted in up-regulation of C5a receptor, but not C3a receptor. Furthermore, human serum induced expression of pro-IL-1β and enabled IL-1β secretion in response to lipofuscin phototoxicity, thus indicating inflammasome priming. Complement heat-inactivation, C5 depletion, and C5a receptor inhibition suppressed the priming effect of human serum whereas recombinant C5a likewise induced priming. Conditioned medium of inflammasome-activated RPE cells provided an additional priming effect that was mediated by the IL-1 receptor. These results identify complement activation product C5a as a priming signal for RPE cells that allows for subsequent inflammasome activation by stimuli such as lipofuscin-mediated photooxidative damage. This molecular pathway provides a functional link between key factors of AMD pathogenesis including lipofuscin accumulation, photooxidative damage, complement activation, and RPE degeneration and may provide novel therapeutic targets in this disease.     

The Effect of Cellular Stress on T and B Cell Memory Pathways in Immunized and Unimmunized BALB/c Mice

Immunological memory is a fundamental function of vaccination. The antigenic breakdown products of the vaccine may not persist, and undefined tonic stimulation has been proposed to maintain the specific memory. We have suggested that cellular stress agents to which the immune cells are constantly exposed may be responsible for tonic stimulation. Here we have studied four stress agents: sodium arsenite, an oxidative agent; Gramicidin, eliciting K⁺ efflux and calcium influx; dithiocarbamate, a metal ionophore; and aluminum hydroxide (alum), an immunological adjuvant. The aims of this study are to extend these investigations to T and B cell responses of unimmunized and ovalbumin (OVA)-immunized BALB/c mice, and furthermore, to ascertain whether stress is involved in optimal expression of memory B cells, as demonstrated in CD4⁺ T cells. Examination of the homeostatic pathway defined by IL-15/IL-15R (IL-15 receptor) interaction and the inflammasome pathway defined by the IL-1-IL-1R interaction between dendritic cells (DC) and CD4⁺ T cells suggests that both pathways are involved in the development of optimal expression of CD4⁺CD45RO⁺ memory T cells in unimmunized and OVA-immunized BALB/c mice. Furthermore, significant direct correlation was found between CD4⁺CD44⁺ memory T cells and both IL-15 of the homeostatic and IL-1β of the inflammasome pathways. However, CD19⁺CD27⁺ memory B cells in vivo seem to utilize only the IL-15/IL-15R homeostatic pathway, although the proliferative responses are enhanced by the stress agents. Altogether, stress agents may up-regulate unimmunized and OVA-immunized CD4⁺CD44⁺ memory T cells by the homeostatic and inflammasome pathways. However, the CD19⁺CD27⁺ memory B cells utilize only the homeostatic pathway.     

Novel Insights into Interleukin 6 (IL-6) Cis- and Trans-signaling Pathways by Differentially Manipulating the Assembly of the IL-6 Signaling Complex

The IL-6 signaling complex is described as a hexamer, formed by the association of two IL-6·IL-6 receptor (IL-6R)·gp130 trimers, with gp130 being the signal transducer inducing cis- and trans-mediated signaling via a membrane-bound or soluble form of the IL-6R, respectively. 25F10 is an anti-mouse IL-6R mAb that binds to both membrane-bound IL-6R and soluble IL-6R with the unique property of specifically inhibiting trans-mediated signaling events. In this study, epitope mapping revealed that 25F10 interacts at site IIb of IL-6R but allows the binding of IL-6 to the IL-6R and the recruitment of gp130, forming a trimer complex. Binding of 25F10 to IL-6R prevented the formation of the hexameric complex obligate for trans-mediated signaling, suggesting that the cis- and trans-modes of IL-6 signaling adopt different mechanisms for receptor complex assembly. To study this phenomenon also in the human system, we developed NI-1201, a mAb that targets, in the human IL-6R sequence, the epitope recognized by 25F10 for mice. Interestingly, NI-1201, however, did not selectively inhibit human IL-6 trans-signaling, although both mAbs produced beneficial outcomes in conditions of exacerbated IL-6 as compared with a site I-directed mAb. These findings shed light on the complexity of IL-6 signaling. First, triggering cis- versus trans-mediated IL-6 signaling occurs via distinctive mechanisms for receptor complex assembly in mice. Second, the formation of the receptor complex leading to cis- and trans-signaling biology in mice and humans is different, and this should be taken into account when developing strategies to inhibit IL-6 clinically.     

The pathogenesis of thyroid autoimmune diseases: New T lymphocytes – Cytokines circuits beyond the Th1−Th2 paradigm

Autoimmune thyroid disease (AITD) is one of the most common organ-specific autoimmune disorders. It mainly manifests as Hashimoto's thyroiditis (HT) and Graves’ disease (GD). HT is characteristic of hypothyroidism resulting from the destruction of the thyroid while GD is characteristic of hyperthyroidism due to excessive production of thyroid hormone induced by thyrotropin receptor-specific stimulatory autoantibodies. T lymphocytes and their secretory cytokines play indispensable roles in modulating immune responses, but their roles are often complex and full of interactions among distinct components of the immune system. Dysfunction of these T cells or aberrant expressions of these cytokines can cause the breakdown of immune tolerance and result in aberrant immune responses during the development of AITDs. This review summarizes recently identified T subsets and related cytokines and their roles in the pathogenesis of AITDs with the hope to provide a better understanding of the precise roles of notably identified T subsets in AITDs and facilitate the discovery of functional molecules or novel immune therapeutic targets for AITDs.     

Characterization of proinflammatory cytokine production and CD14 expression by murine alveolar macrophage cell lines

Summary Alveolar macrophages, which play a central role in lung defense, produce cytokines that help orchestrate local inflammatory responses. In sepsis and other pathological conditions, bacterial lipopolysaccharide endotoxin can induce alveolar macrophages (AM) to release proinflammatory cytokines, including tumor necrosis factor-alpha, interleukin-1, and interleukin-6. Studying the mechanisms that control alveolar macrophage cytokine production may lead to better therapies for conditions involving inflammatory lung injury. We and others have noted significant differences between alveolar macrophages and peritoneal macrophages, but large numbers of human or murine alveolar macrophages are rarely available for detailed mechanistic studies. We have obtained three murine alveolar macrophage cell lines (AMJ2C8, AMJ2C11, and AMJ2C20) and have begun to characterize their cytokine responses to proinflammatory stimuli. We measured the effects of endotoxin, interferon gamma, and the combination of the two on production of tumor necrosis factor, interleukin-1 beta, and interleukin-6 in each line. We also studied the expression of the endotoxin receptor CD14 by these cells, and investigated the effect of serum on their endotoxin responsiveness. We show here that all three of the cell lines responded in a manner comparable to that of primary murine alveolar macrophages. Observed variations between these lines may reflect the documented heterogeneity seen in populations of primary alveolar macrophages. These cell lines should expand the repertoire of tools available to investigators studying regulation of murine alveolar macrophage responses.