Differential production of inflammatory chemokines by murine dendritic cell subsets

Dendritic cells (DC) are efficient antigen presenting cells with the ability to activate na?ve T cells. Murine DC represent a heterogeneous population that can be subdivided into distinct subsets, including the conventional DC (cDC) which are either CD4(-)CD8(-) (DN), CD4(+)CD8(-) (CD4+) or CD4(-)CD8(+) (CD8+) subsets and the plasmacytoid DC (pDC), which have different immune regulatory functions. In this study, we investigated the differential expression of genes encoding the inflammatory chemokines Mip-1alpha, Mip-1beta and Rantes, and the secretion of these chemokines, among splenic DC subsets. These chemokine genes were expressed at higher levels by the splenic CD4+ and DN cDC subsets compared with the CD8+ cDC, in both the resting and activated states in vivo. Both the pDC and cDC subsets displayed increases in chemokine secretion in response to a range of toll-like receptor (TLR) stimuli in vitro. Whilst the pDC were the highest producers of Mip-1alpha and Mip-1beta in response to some TLR stimuli, the DN and CD4+ cDC subsets were the superior producers of Rantes. Overall, of the cDC, the CD4+ cDC produced all chemokines most efficiently, both at a basal level, and in response to most TLR stimuli. Thus, we report a new functional difference between the murine splenic cDC subsets, with the CD4+ cDC demonstrating the most efficient production of the inflammatory chemokines Mip-1alpha, Mip-1beta and Rantes.     

Calcitonin gene-related peptide in cardiovascular tissues of the rat

The distribution of calcitonin gene-related peptide immunoreactivity in the cardiovascular system of the rat was investigated by radioimmunoassay and immunocytochemistry. The nature of the immunoreactivity was studied by gel permeation and high performance liquid chromatography. Immunocytochemistry demonstrated the existence of calcitonin gene-related peptide-containing nerve fibres throughout the cardiovascular system. These were present in all regions of the heart, particularly in association with the coronary arteries, within the papillary muscles and within the sinoatrial and atrioventricular nodes. Calcitonin gene-related peptide-containing fibres were found mainly in the adventitia of the arteries and veins. Calcitonin gene-related peptide concentrations were high in major arteries and veins but comparatively low in the heart, aortic arch and thoracic aorta. Chromatography showed that approximately 70% of the total immunoreactivity was identical to synthetic calcitonin gene-related peptide. Calcitonin gene-related peptide concentrations in the blood vessels of rats treated neonatally with capsaicin were not found to be significantly different from those in control animals although capsaicin caused significant reductions of calcitonin gene-related peptide levels in certain other tissues. The results of this study suggest that calcitonin gene-related peptide-containing fibres are likely to be of importance in the innervation of vascular tissues and raise the possibility that these fibres are different in character from calcitonin gene-related peptide-containing fibres found in other tissues.     

Calcitonin gene-related peptide is present in mammalian cerebrovascular nerve fibres and dilates pial and peripheral arteries

Calcitonin gene-related peptide (CGRP) is a novel 37-amino acid peptide occurring in neurones within sensory ganglia, in brain stem, as well as in the walls of blood vessels of peripheral organs. Pial arteries of cat showed a well-developed supply of CGRP-positive nerve fibres. The peptide was found to be a potent dilator of both pial and peripheral vessels of rabbit and cat, and of pial vessels from man. The dilatory effect was independent of the vascular endothelium and was not mediated through adrenergic, cholinergic or histaminergic smooth muscle receptors. The neurogenic vasoconstriction induced by electrical field stimulation was temporarily inhibited by CGRP, as studied in central ear arteries from rabbits. The results suggest that CGRP is a transmitter or modulator playing a role in the regulation of vascular tone.     

Calcitonin gene-related peptide inhibits spontaneous contractions in human uterus and fallopian tube

The localization and effects of calcitonin gene-related peptide (CGRP) in the human uterus and fallopian tube were investigated. CGRP-immunoreactive nerve fibers were found in the muscular layers, around blood vessels and close to the epithelium. The oviduct and uterine cervix were more densely innervated than the corpus of the uterus. Substance P (SP)-like immunoreactivity was found in nerves with an overlapping distribution to that of CGRP-positive fibers. CGRP (2 X 10(-10) to 10(-7) M) dose-dependently and reversibly inhibited spontaneous contractions of uterine and oviductal strips, as well as SP-induced contractions in the oviduct. A role for CGRP-containing nerve fibers in regulation of motor activity in human female reproductive organs is suggested.     

降钙素基因相关肽诱导藻酸钙凝胶复合脂肪干细胞的成骨细胞分化

背景：降钙素基因相关肽已被证实具有诱导成骨细胞分化作用,但其是否可使三维培养下的脂肪干细胞向成骨细胞分化构建组织工程骨的相关报道少见。 目的：探讨外源性降钙素基因相关肽诱导兔脂肪干细胞复合藻酸钙凝胶三维培养成骨分化的可行性。 方法：取新西兰兔双侧腹股沟区皮下脂肪垫,Ⅰ型胶原酶消化离心贴壁法分离培养脂肪干细胞,取第3代与海藻酸钠混合制备凝胶,于24孔板分组培养：对照组加入含10^-2 mol/L β-甘油磷酸钠、10^-7 mol/L地塞米松、50 mg/L抗坏血酸、体积分数10%胎牛血清的DMEM/F-12骨诱导培养基,实验组在此基础上再加入1.5 µg/L降钙素基因相关肽进行诱导培养。于诱导不同时间点MTT法检测细胞增殖,RT-PCR法检测诱导细胞Ⅰ型胶原和骨钙素mRNA的表达,并检测碱性磷酸酶及钙离子浓度。 结果与结论：兔脂肪干细胞的增殖曲线呈“S”型,实验组诱导1,3,5,7,14,21 d的A值高于对照组(P < 0.05);诱导2周后两组细胞碱性磷酸酶、茜素红染色均阳性,但实验组钙结节较对照组明显增多。实验组诱导7,14 d的Ⅰ型胶原和骨钙素mRNA表达均强于对照组。实验组诱导1,2,3,4周的碱性磷酸酶活性及钙离子浓度均高于对照组(P< 0.05)。结果表明降钙素基因相关肽能诱导复合藻酸钙凝胶的脂肪干细胞向成骨细胞分化。     

降钙素基因相关肽合成与释放调节

降钙素基因相关肽（calcitonin gene-related peptide, CGRP）是迄今发现的最强的舒血管物质,具有多种重要的生物学作用。作为感觉神经主要递质,CGRP主要由背根神经节合成,某些非神经细胞(如淋巴细胞和内皮细胞)也有表达。CGRP的合成与释放受多种因素调节,除辣椒素受体外,肾上腺素受体、血管紧张素受体、神经生长因子受体和一氧化氮等也参与了CGRP合成与释放的调节。     

Detection of calcitonin and calcitonin gene-related peptide mRNA in human medullary thyroid carcinoma. A retrospective study

In Situ hybridization finds many applications in modern pathology. In many cases, special attention is paid to the processing of the tissues prior to in situ hybridization. In order to investigate the value of RNA in situ hybridization (RISH) in retrospective studies, we performed RISH for calcitonin and calcitonin gene-related peptide (CGRP)-I and HomRNA in eight medullary thyroid carcinomas processed in 1981–1983. RISH was successful with radioactive calcitonin and CGRP-1 probes. With biotinylated probes, only calcitcnin-specific probes gave adequate results. The concentrations of CGRP mRNA were probably too low to be detected by non-radioactive RISH. The results of RISH were correlated with the immunohistochemical localization of the polypeptides. The results matched in all cases except one, where hybridization for calcitonin mRNA was found, but no immunoreactive calcitonin polypeptide. We con-clude that RISH can be successfully used for retrospective analysis, even after long storage of tissue embedded in poraffin.     

臂丛损伤后脊髓前后角降钙素基因相关肽的表达及其意义

目的：观察大鼠臂丛损伤后脊髓降钙素基因相关肽(CGRP)的表达变化规律。方法：用大鼠建立3种臂丛损伤模型：右C_7前根撕脱(A组);右C_7前根撕脱 同侧C_5～T_1后根离断(B组);有C_7前根撕脱 右C_5与C_6之间脊髓半横断(C组)。术后1、3、7和14d取C_7节段脊髓,采用免疫组织化学方法和图像分析技术,对脊髓前角和后角CGRP的表达进行检测与分析。结果：各损伤组脊髓前角CGRP表达在术后1～7d呈上升趋势,7d达高峰,然后缓慢下降;脊髓后角CGRP表达在术后1～14d呈显著下降趋势。A组CGRP表达量最高,B组最低,C组居中。结论：臂丛损伤后脊髓前角和后角表达及作用呈不一致性。前角CGRP可能参与神经损伤再生的修复机制;后角CGRP可能与伤害性刺激传导有关。     

Contrasting roles for RANTES and macrophage inflammatory protein-1 alpha (MIP-1 alpha) in a murine model of allergic peritonitis.

Cell accumulation and CC chemokine production were assessed in the peritoneal cavity of ovalbumin (OVA)-sensitized mice following antigen challenge. Intraperitoneal challenge with OVA induced a significant eosinophil influx from 6 h post-challenge with increased numbers persisting at 24 h. At 6 h there was also a marked presence of neutrophils. Messenger RNA expression and protein levels for the chemokines RANTES and MIP-1 alpha were measured in the cell pellets and supernatants, respectively, from peritoneal washes following OVA challenge. RANTES mRNA was detected from 2 h to 4 h following OVA injection, whereas mRNA for MIP-1 alpha was only detectable at 4 h. RANTES protein was first detected from 4 h after OVA injection and by 24 h the protein levels had increased further. Basal levels of MIP-1 alpha were detected in peritoneal washes. These levels peaked at 2 h after OVA challenge and rapidly declined to basal levels by 6 h. A functional role for the chemokines was assessed using neutralizing polyclonal antibodies. Co-injection of OVA with anti-RANTES antibodies resulted in a significant inhibition of eosinophil infiltration into the cavity at 6 h and 24 h (63% and 52% inhibition, respectively) without significantly influencing the number of neutrophils present. In contrast, injection of anti-MIP-1 alpha antibodies only inhibited neutrophil migration at the 6 h time point by 44% without significantly affecting the accumulation of eosinophils. These results demonstrate an important role for RANTES in mediating eosinophil influx in allergic inflammation and a contrasting role for MIP-1 alpha in mediating neutrophil recruitment.     

Developmental studies on vasoactive intestinal peptide,substance P and calcitonin gene-related peptide in salivary glands of postnatal rats

The development of vasoactive intestinal peptide, substance P and calcitonin gene-related peptide in parotid, submandibular and sublingual glands of the male rat was followed by immunochemistry and immunocytochemistry. The total amounts of these peptides increased in surges during the first 8 weeks of the animal's life; one within 2–4 weeks and the other beginning 1–2 weeks later. Nerve fibres containing these peptides were present at birth showing a pattern of distribution similar to that in adults. During the first 4 weeks the nerve fibres increased in number.     

小鼠脊神经节内P2X2、P2X3受体与降钙素基因相关肽和植物凝集素结合位点的共存

目的:研究小鼠脊神经节内ATP受体P2X2、P2X3与降钙素基因相关肽(CGRP)、植物凝集素IB4(IB4)结合位点的共存。方法:在成年c57/6小鼠脊神经节,用免疫组织化学荧光三标方法结合激光共聚焦显微镜技术观察。结果:脊神经节内可见大量P2X2、P2X3阳性细胞和纤维;P2X2阳性细胞多为大型和小型神经元,P2X3阳性细胞多为小型神经元;有34.2%±3.9%P2X2阳性细胞含有CGRP;但只有4.6%±1.1%P2X3阳性神经元含有CGRP。许多感觉神经元结合IB4;有62.4%±4.3%P2X2和89.5%±4.1%P2X3阳性神经元分别结合IB4。未观察到P2X2/CGRP/IB4或P2X3/CGRP/IB4三标神经元。结论:小鼠脊神经节内P2X2、P2X3的表达与IB4结合位点之间密切相关,部分P2X2受体与CGRP共存。     

降钙素基因相关肽对大鼠血管平滑肌细胞增殖及表型转化的影响

目的:探讨降钙基因相关肽(CGRP)对大鼠血管平滑肌细胞(VSMC)增殖及表型转化的影响,并对VSMC增殖模型的应用价值作出评估。方法:取大鼠主动脉,分成CGRP作用和无CGRP作用2个实验组,体外培养8d,收集血管前24h用BrdU标记。H-E染色和5-BrdU免疫细胞化学染色观察增殖变化;RT-PCR检测高血压相关基因1(HRG-1)和SM22α基因表达。结果:血管中膜可见大量棕黄色标记增殖的细胞核,VSMC明显增生,HRG-1和SM22α mRNA表达明显减少;而加入CGRP共培养组标记的增殖细胞大大减少,也未见有斑块增生,HRG-1和SM22α mRNA表达明显上调。结论:CGRP对VSMC增殖有抑制作用并可使VSMC从合成型向收缩型转化。     

An increased MRP8/14 expression and adhesion, but a decreased migration towards proinflammatory chemokines of type 1 diabetes monocytes

In the early development of type 1 diabetes macrophages and dendritic cells accumulate around the islets of Langerhans at sites of fibronectin expression. It is thought that these macrophages and dendritic cells are derived from blood monocytes. Previously, we showed an increased serum level of MRP8/14 in type 1 diabetes patients that induced healthy monocytes to adhere more strongly to fibronectin (FN). Here we show that MRP8/14 is expressed and produced at a higher level by type 1 diabetes monocytes, particularly after adhesion to FN, creating a positive feedback mechanism for a high fibronectin-adhesive capacity. Also adhesion to endothelial cells was increased in type 1 diabetes monocytes. Despite this increased adhesion the transendothelial migration of monocytes of type 1 diabetes patients was decreased towards the proinflammatory chemokines CCL2 and CCL3. Because non-obese diabetic (NOD) mouse monocytes show a similar defective proinflammatory migration, we argue that an impaired monocyte migration towards proinflammatory chemokines might be a hallmark of autoimmune diabetes. This hampered monocyte response to proinflammatory chemokines questions whether the early macrophage and dendritic cell accumulation in the diabetic pancreas originates from an inflammatory-driven influx of monocytes. We also show that the migration of type 1 diabetes monocytes towards the lymphoid tissue-related CCL19 was increased and correlated with an increased CCR7 surface expression on the monocytes. Because NOD mice show a high expression of these lymphoid tissue-related chemokines in the early pancreas it is more likely that the early macrophage and dendritic cell accumulation in the diabetic pancreas is related to an aberrant high expression of lymphoid tissue-related chemokines in the pancreas.     

CC chemokine receptor 2 regulates leukocyte recruitment and IL-10 production during acute polymicrobial sepsis

Chemokine receptors are important for recruiting leukocytes to sites of infection and may contribute to immune cell activation. The present study investigated the role of the chemokine receptor CCR2 in polymicrobial septic peritonitis. The results showed that peritoneal production of the CCR2 ligands CCL2 and CCL12 in septic mice was largely independent of the common Toll-like receptor signaling adaptor MyD88. Antibody blockade of CCR2 reduced the recruitment of macrophages and neutrophils to the infected peritoneal cavities of both wild-type and MyD88-deficient mice, suggesting that CCR2 engagement contributes to the MyD88-independent cellular response against polymicrobial septic peritonitis. Notably, administration of blocking CCR2 antibodies markedly increased local and systemic IL-10 levels in septic wild-type mice, whereas IL-10 was not detected in MyD88-deficient mice irrespective of whether CCR2 was blocked or not. Inhibition of CCR2 directly augmented Toll-like receptor-induced IL-10, but not TNF and IL-6, production of macrophages in vitro. Concomitant with enhanced IL-10 production, CCR2 blockade caused impaired bacterial clearance and aggravated kidney injury in wild-type, but not MyD88-null mice. These results indicate that CCR2 engagement modulates the innate immune response to polymicrobial septic peritonitis by both MyD88-dependent and -independent processes and suggest that a major function of CCR2 in sepsis is to attenuate IL-10 production and IL-10-mediated suppression of host defense.     

Calcitonin gene-related peptide immunoreactivity selectively labels accessory optic nuclei and pathways of the rat visual system

The present study shows the distribution of calcitonin gene-related peptide (CGRP)-immunolabeled neuronal somata and fibers in the accessory optic system of adult rats. CGRP-immunoreactive cell bodies were small to medium-sized and mostly fusiform or oval-shaped. Both immunolabeled somata and fibers were found in the dorsal and lateral terminal nuclei as well as in the interstitial nucleus of the superior fasciculus (posterior fibers); whereas only immunoreactive fibers were found in the ventral division of the medial terminal nucleus, particularly its rostral portion. These results indicate that CGRP-containing neurons are present in all nuclear components of the accessory optic system and suggest that this neuropeptide may play a neuromodulative role in eye movements. Received: 2 April 1997 / Accepted: 2 June 1997     

Altered intracellular expression of the chemokines MIP-1alpha,MIP-1beta and IL-8 by peripheral blood CD4+ and CD8+ T cells in mild allergic asthma

BACKGROUND: The ability of chemokines to regulate Th1 and Th2 responses suggests a role in the pathogenesis of atopic disorders such as allergic asthma where Th2 response dominance has been observed. Although the impact of allergic asthma on local chemokine production in the lung has been the subject of investigation, little is know about the influence of disease progression on peripheral chemokine production. We now report use of whole blood culture and flow cytometry to assess the influence of mild allergic asthma on peripheral T-cell chemokine expression. METHODS: Study participants included patients with mild allergic asthma (n = 7) and nonasthmatic controls (n = 7). Following in vitro stimulation of peripheral venous blood with phorbol 12-myristate acetate (PMA) and ionomycin, flow cytometry was used to estimate the percentage of CD4+ and CD8+ T cells producing a number of chemokines, including macrophage inflammatory proteins MIP-1alpha and MIP-1beta, RANTES (regulated on activation, T-cell expressed and secreted), monocytic chemotactic protein-1 (MCP)-1, and interleukin (IL)-8, or the cytokines interferon (IFN)-gamma and IL-4. Serum levels of MIP-1alpha, MIP-1beta, RANTES, MCP-1, IL-8, IFN-gamma and IL-4 were also assessed by quantitative ELISA. RESULTS: Intracellular expression of MIP-1beta by CD4+ and CD8+ T cells from allergic asthmatics was significantly reduced in comparison to that observed for nonasthmatics (median = 2.29% (1.75-3.50) vs 4.57% (3.38-6.64), P = 0.05; 14.20% (13.18-17.88) vs 44.10% (30.38-48.70), P = 0.01). Similarly, intracellular expression of MIP-1alpha by CD8+ T cells from allergic asthmatics was also significantly lower (3.67% (1.17-5.42) vs 17.10% (4.97-20.43), P = 0.05). Conversely, IL-8 expression by both CD4+ and CD8+ T cells from allergic asthmatics demonstrated significant enhancement (9.93% (7.77-11.28) vs 4.14% (3.61-7.11), P = 0.05; 8.40% (6.97-10.04) vs 4.98% (3.37-6.08), P = 0.05). Examination of intracellular IFN-gamma and IL-4 revealed no significant difference in the expression of either cytokine by CD4+ T-cells from allergic asthmatics and nonasthmatics. In contrast, expression of IFN-gamma was significantly reduced in CD8+ T-cells from allergic asthmatics (24.60% (21.08-32.50) vs 48.40% (41.50-55.28), P = 0.01). CONCLUSIONS: The occurrence in mild allergic asthma of peripheral T-cell chemokine expression suggestive of a diminished Th1 response, coinciding with marginal change in cytokine profiles indicative of a Th2 response bias, confirms the importance of chemokine involvement in the etiology of allergic asthma. The ability to use whole blood culture to estimate chemokine expression in T cell subsets may ultimately provide a practical means to evaluate disease status and to monitor early intervention therapies which target chemokines.     

Differential distribution of calcitonin gene-related peptide and its receptor components in the human trigeminal ganglion

Calcitonin gene related peptide (CGRP) has a key role in migraine and recently CGRP receptor antagonists have demonstrated clinical efficacy in the treatment of migraine. However, it remains unclear where the CGRP receptors are located within the CGRP signaling pathway in the human trigeminal system and hence the potential antagonist sites of action remain unknown. Therefore we designed a study to evaluate the localization of CGRP and its receptor components calcitonin receptor-like receptor (CLR) and receptor activity modifying protein (RAMP) 1 in the human trigeminal ganglion using immunohistochemistry and compare with that of rat. Antibodies against purified CLR and RAMP1 proteins were produced and characterized for this study. Trigeminal ganglia were obtained at autopsy from adult subjects and sections from rat trigeminal ganglia were used to compare the immunostaining pattern. The number of cells expressing CGRP, CLR and RAMP1, respectively, were counted. In addition, the glial cells of trigeminal ganglion, particularly the satellite glial cell, were studied to understand a possible relation. We observed immunoreactivity for CGRP, CLR and RAMP1, in the human trigeminal ganglion: 49% of the neurons expressed CGRP, 37% CLR and 36% RAMP1. Co-localization of CGRP and the receptor components was rarely found. There were no CGRP immunoreactions in the glial cells; however some of the glial cells displayed CLR and RAMP1 immunoreactivity. Similar results were observed in rat trigeminal ganglia. We report that human and rat trigeminal neurons store CGRP, CLR and RAMP1; however, CGRP and CLR/RAMP1 do not co-localize regularly but are found in separate neurons. Glial cells also contain the CGRP receptor components but not CGRP. Our results indicate, for the first time, the possibility of CGRP signaling in the human trigeminal ganglion involving both neurons and satellite glial cells. This suggests a possible site of action for the novel CGRP receptor antagonists in migraine therapy.     

Calcitonin gene-related peptide immunoreactive sensory neurons in the vagal and glossopharyngeal ganglia innervating the larynx of the rat

We have examined whether calcitonin gene-related peptide-immunoreactive (CGRP-ir) neurons in the vagal and glossopharyngeal ganglia innervate the larynx. Many CGRP-ir neurons were located mostly in the superior glossopharyngeal–jugular ganglion complex that was fused the superior glossopharyngeal ganglion and the jugular ganglion in the cranial cavity. When Fluorogold was applied to the cut end of the superior laryngeal nerve (SLN) or the recurrent laryngeal nerve (RLN), many Fluorogold-labeled neurons were found in the superior glossopharyngeal–jugular ganglion complex and the nodose ganglion. Double-labeling for CGRP and Fluorogold showed that about 80% of Fluorogold-labeled neurons in the superior glossopharyngeal–jugular ganglion complex expressed CGRP-like immunoreactivity in the case of application to the SLN, and about 50% of Fluorogold-labeled neurons expressed CGRP-like immunoreactivity in the case of the RLN. Only a few double-labeled neurons were found in the nodose ganglion. The number of the Fluorogold-labeled neurons and double-labeled neurons in the superior glossopharyngeal–jugular ganglion complex in the case of the SLN was larger than that in the case of the RLN. These results indicate that sensory information from the larynx might be conveyed by many CGRP-ir neurons located in the superior glossopharyngeal–jugular ganglion complex by way of the SLN and the RLN.