Cerebral microdialysis of interleukin (IL)-1ß and IL-6: extraction efficiency and production in the acute phase after severe traumatic brain injury in rats

Background

As a research tool, cerebral microdialysis might be a useful technique in monitoring the release of cytokines into the extracellular fluid (ECF) following traumatic brain injury (TBI). We established extraction efficiency of Interleukin(IL)-1ß and Interleukin(IL)-6 by an in vitro microdialysis-perfusion system, followed by in vivo determination of the temporal profile of extracellular fluid cytokines after severe TBI in rats.

Materials and methods

In vitro experiments using a polyether sulfon (PES) microdialysis probe especially developed for recovery of macromolecules such as cytokines, were carried out to establish the extraction efficiency of IL-1ß and IL-6 from artificial cerebrospinal fluid (CSF) with defined IL-1ß and IL-6 concentrations. In vivo experiments in which rats were subjected to TBI or sham and microdialysis samples were collected from the parietal lobe for measurement of cytokines.

Findings

The extraction efficiency was maximal 6.05% (range, 5.97–6.13%) at 0.5 µl/min^?1 and decreased at higher flow rates. Both cytokines were detectable in the dialysates. Highest IL-1ß levels were found within 200 min, highest IL-6 concentrations were detected at later intervals (200–400 min). No differences were found between the TBI and control groups.

Conclusions

Cerebral microdialysis allows measurement of cytokine secretion in the ECF of brain tissue in rats.     

Pathophysiology of pulmonary complications of acute pancreatitis

introDuCtion Acute pancreatitis (AP), an acute inflammatory process of the pancreas in its severe form, is complicated by the development of multi-organ dysfunction syndrome(MODS) with a mortality of 15%-20%. Regardless of etiology, once AP is initiated t…     

静脉注射丙种球蛋白无反应型川崎病Th17细胞的变化及意义

目的 探讨Th17细胞在静脉注射丙种球蛋白(IVIG)无反应型川崎病(KD)免疫发病机制中的作用.方法 选取KD患儿45例,其中IVIG敏感型KD 35例,IVIG无反应型KD 10例,同年龄健康对照组30名.KD患儿分别于IVIG治疗前后直接取血备检,IVIG无反应型KD分别在病程第8、9、11天取血备检.采用实时荧光定量聚合酶链反应(PCR)检测CD4~+T细胞白细胞介素(IL)-17A/F、转录因子ROR-γt mRNA表达;采用流式细胞术检测外周血Th17细胞占CD4~+T细胞比例.应用酶联免疫吸附试验(ELISA)检测Th17细胞相关的细胞因子IL-17A和IL-6的表达.结果 ①急性期KD患儿CD4~+T细胞IL-17A/F表达明显高于对照组(P<0.01);②急性期IVIG无反应型KD患儿CD4~+T细胞内IL-17蛋白、IL-17A/F mRNA、Th17细胞转录因子ROR-γt的基因表达明显高于IVIG敏感型KD,经IVIG治疗后敏感型KDTh17细胞相关因子表达明显降低(P<0.01),无反应型KD Th17细胞相关因子仍持续高表达(P>0.05);③急性期KD患儿治疗前IL-17A和IL-6血浓度明显高于对照组(P<0.01),其中IVIG无反应型KD活化细胞因子水平明显高于1VIG敏感型KD组(P<0.01).经治疗后均有下降趋势,但IVIG无反应型KD仍高于敏感型KD(P<0.01);④甲泼尼龙冲击治疗IVIG无反应型KD当天退热.血浆IL-6,IL-17A较前明显降低,C反应蛋白(CRP)恢复快,能够迅速控制血管炎性反应.结论 Th17细胞过度活化可能是导致IVIG无反应型KD的原因之一.     

Cytokine production by whole blood cells: relationship to interleukin gene polymorphism and bone mass

The aims of this study were to investigate the relationships between the production of interleukin-1 (IL-1), and IL-6 system by whole blood cells, and bone mineral density (BMD), and polymorphisms in IL-1 system and IL-6 gene in postmenopausal Korean women. The production of IL-1alpha, IL-1beta, IL-1 receptor antagonist (IL-1ra), IL-6, and soluble IL-6 receptor (sIL-6r) by lipopolysaccharide-stimulated whole blood cells was measured by ELISA in 110 subjects. Serum osteocalcin, C-telopeptide of type I collagen, and BMD at lumbar spine and proximal femur were measured. IL-1alphaC(-889)T polymorphism, IL-1beta C(-511)T polymorphism, 86-base pair variable number tandem repeat polymorphism in the IL-1ra gene, and IL-6 C(-634)G polymorphism were analyzed. The production of IL-1beta correlated positively with BMD at femoral neck, whereas the production of other ILs did not correlate with BMD at the skeletal sites examined. No significant differences in the production of ILs were observed among normal, osteopenic and osteoporotic postmenopausal women, and among the different IL system polymorphisms groups studied. No correlation between bone turnover markers and the production of ILs was noted. In conclusion IL-1beta may regulate bone metabolism at femoral neck, and the IL system polymorphism do not affect the production of ILs by whole blood cells.     

Interleukin-2, soluble interleukin-2-receptor,neopterin,l-tryptophan and β2-microglobulin levels in CSF and serum of patients with relapsing-remitting or chronic-progressive multiple sclerosis

Cerebrospinal fluid (CSF) and serum levels of interleukin-2 (IL-2), soluble IL-2 receptors (sIL-2R), neopterin,l-tryptophan (l-TRP) and ₂-microglobulin ((₂-M) were measured in 31 untreated multiple sclerosis patients in acute exacerbation and 27 normal controls. Twenty-six patients showed the relapsing-remitting type of disease (RRMS); 5 had a chronic-progressive course (CPMS). No changes in serum IL-2 and sIL-2R were found between RRMS patients and controls, whereas serum and CSF levels as well as the CSF/serum ratio of neopterin were significantly elevated in the RRMS group. IL-2 was not detectable in CSF of patients or controls and sIL-2R levels were at the level of the lower detection (LD) sensitivity of the ELISA method. Four of 23 RRMS patients versus 1 of 25 controls showed CSF sIL-2R levels above the LD sensitivity, indicating a trend towards elevation in acute relapse. No difference was found in serum and CSFl-TRP and ₂-M of patients and controls. In CSF of RRMS patients neopterin andl-TRP correlated negatively, reflecting the interferon-gamma mediated activation of macrophages in acute relapse. A significant positive correlation (Spearman rank 0.57,P = 0.001) between serum IL-2 levels and duration of acute relapse (mean 30 days) warrants further evaluation.     

大鼠枯否细胞CD14表达的实验研究

目的:探讨大鼠枯否细胞(KC)中CD14表达的变化。方法:应用不同浓度(1μg/L-10mg/L)或同一浓度(10mg/L)的脂多糖(LPS)在不同时间(0.5h-24h)刺激培养大鼠48h的KC并测定其CD14、肿瘤坏死因子α(TNFα)和白介素6(IL-6)表达的变化。结果:LPS能明显上调KC中CD14、TLR4表达,且其表达量与LPS浓度及时间呈正相关,且在3-6h左右达到高峰;同时,KC产生的活性介质亦能明显上调其CD14的表达。结论:LPS及其刺激KC后产生的活性介质能明显上调CD14的表达,且在CD14的表达中存在一个自身调节环。     

IL-24基因与肿瘤免疫治疗

白细胞介素-24(IL-24)又称为黑色素瘤分化相关基因-7(MDA-7),它主要由CD3+ T淋巴细胞和单核细胞表达,为分泌蛋白,由206个氨基酸组成,属于IL-10家族成员。IL-24是第1个被报道的具有白介素作用的肿瘤抑制分子,具有选择性的广谱抗肿瘤活性。IL-24基因通过抑制血管形成、激活生长抑制和DNA损伤基因(GADD)等信号传导途径,抑制肿瘤细胞生长和促进肿瘤细胞凋亡,而对正常细胞无明显影响。INGN241是一种新开发的基因治疗制剂,对多种肿瘤具有抑制和治疗作用。     

急性肺损伤大鼠肺组织白细胞介素-13表达的初步研究

目的：动态观察急性肺损伤（ＡＬＩ）大鼠肺组织白细胞介素－１３（ＩＬ－１３）mＲＮ Ａ表达的变化,初步探讨ＩＬ－１３mＲＮＡ的表达。结果：正常肺组织表达一定水平的Ｉ Ｌ－１３mＲＮＡ;在ＡＬＩ大鼠肺组织,ＩＬ－１３mＲＮＡ表达呈短暂性上调,随即逐渐下调。结论：正常肺组织可表达一定水平的ＩＬ－１３mＲＮＡ;在ＡＬＩ肺组织,ＩＬ－ １３mＲＮＡ表达逐渐下调,提示局部抗炎作用减弱,可能引起抗炎和致炎作用失衡,从而     

Catecholamines, infection, and death in acute ischemic stroke

Experimental studies have recently suggested that acute ischemia may facilitate the appearance of fatal infections as part of a brain-induced immunodepression syndrome. However, the mechanisms and neurological consequences of infections complicating acute ischemic stroke have received much less attention at the bedside. The incidence of infection and death after non-septic stroke was compared in this prospective study with longitudinal changes of cytokines, leukocytes, normetanephrine (NMN) and metanephrine (MN) in 75 consecutive patients. In multivariate analysis, infection, n = 13 (17%), was associated with the upper quartile of MN (OR 3.51, 95% CI 1.30-9.51), neurological impairment (NIHSS) on admission (OR 3.99, 95% CI 1.34-11.8), monocyte count (OR 1.78, 95% CI 1.13-2.79), and increased interleukin (IL)-10 (OR 1.54, 95% CI 1.00-2.38). Mortality at 3 months, n = 16 (21%), was associated with increased levels of NMN on admission (OR 2.34 95% CI 1.15-4.76), NIHSS score (OR 2.57, 95% CI 1.29-5.11), and higher IL-6 levels (OR 1.29, 95% 1.00-1.67). These findings suggest that acute ischemic stroke is associated with an early activation of the sympathetic adrenomedullar pathway that lowers the threshold of infection and increases the risk of death. Moreover, these findings are independent of the blood borne effects of pro- and anti-inflammatory cytokines, and circulating leukocytes.     

白细胞介素类mRNA在儿童哮喘中异常表达的检测及意义

目的：研究白细胞介素－12（IL－12），IL－13在哮喘发病中的作用。方法：用逆转录聚合酶链反应（RT－PCR）法半定量分析了哮喘急性发作期及正常对照组儿童外周血单个核细胞（PBMC）中IL－12，IL－13mRNA表达水平的变化，同时对IgE水平进行了检测，结果：哮喘组IL－12 mRNA表达减少，IL－13 mRNA表达增多，病情越重，IL－12mRNA表达越少，IL－13 mRNA表达越多，无论IgE升高与否。与对照组比较，IL－12，IL－13mRNA表达，差异均有显著性，结论：IL－12，IL－13可能是构成气道慢性炎症的各类因素之一。