Histamine synthesis is required for granule maturation in murine mast cells

Mast cells are the major sources of histamine, which is released in response to immunological stimulations. The synthesis of histamine is catalyzed by histidine decarboxylase (HDC). Previous studies have shown that Hdc^?/? mast cells exhibit aberrant granule morphology with severely decreased granule content. Here, we investigated whether the histamine synthesized in mast cells regulates the granule maturation of murine mast cells. Several genes, including those encoding granule proteases and enzymes involved in heparin biosynthesis, were downregulated in Hdc^?/? peritoneal mast cells. Impaired granule maturation was also found in Hdc^?/? BM‐derived cultured mast cells when they were cocultured with fibroblasts in the presence of c‐kit ligand. Exogenous application of histamine and several H₄ receptor agonists restored the granule maturation of Hdc^?/? cultured mast cells. However, the maturation of granules was largely normal in Hrh4^?/? peritoneal mast cells. Depletion of cellular histamine with tetrabenazine, an inhibitor of vesicular monoamine transporter‐2, did not affect granule maturation. In vivo experiments with mast cell deficient Kit^W/Kit^W‐v mice indicated that the expression of the Hdc gene in mast cells is required for granule maturation. These results suggest that histamine promotes granule maturation in mast cells and acts as an proinflammatory mediator.     

Functional heterogeneity of mast cells from different species and tissues

Summary The systemic responses of different animals to a number of histamine liberators and the effects of these compounds on isolated tissue mast cells in vitro are examined. Mast cells from different species and even from individual tissues within a single animal are shown to vary markedly in their response to given inducers. On this basis, the usefulness of animal models in predicting whether a particular compound may act as a histamine liberator in man is discussed.     

Influence of DPPE on histamine release from isolated rat mast cells

A second messenger function for histamine has been proposed based on the effects of the anti-estrogen drug DPPE (N,N-diethyl-2-(4-(phenylmethyl)phenoxy) ethanamine.HCl). The ability of DPPE to inhibit concanavalin A-induced histamine release led to the present investigation of its influence on the mast cell response to a wider selection of secretagogues. DPPE was an efficient inhibitor of antigen-induced release, while responses to compound 48/80 were virtually unaffected. Responses to the ionophore A23187 could be enhanced as well as inhibited, whereas the influence of DPPE on the combination of the ionophore and the phorbol ester TPA was variable and small. These results seem to exclude an involvement of a DPPE-sensitive histamine-mediated signal system of common importance in mast cell histamine release.     

肥大细胞体外脱颗粒的检测方法

目的和方法：模拟体内的脱颗粒反应，分别通过荧光分光光度计和酶活力测定方法定量检测组胺和类胰蛋白酶释放，探讨类胰蛋白酶活力测定法检测肥大细胞脱颗粒的可行性。结果：致敏血清和肥大细胞共孵育后在抗原刺激下，引起组胺和类胰蛋白酶剂量依赖性释放，且二者释放是平行的。结论：与组胺的测定比较，类胰蛋白酶活力测定可以用来标记肥大细胞脱颗粒的程度，该法灵敏可靠，简单可行，为临床上诊断变态反应疾病和筛选变应原提供新的检测方法。     

Histamine modulates mast cell degranulation through an indirect mechanism in a model IgE-mediated reaction

Histamine is released in inflammatory reactions and exerts an immunoregulatory function on cells present in the microenvironment. In this study, we compared the effect of histamine on degranulation of mast cells derived from animals bearing a parasitic infection with those from uninfected animals. Peritoneal mast cells (PMC) were obtained 24 days after infection of Wistar rats with Toxocara canis. The degree of degranulation was assessed either morphologically or by measuring the release of beta-hexosaminidase and TNF-alpha. Non-purified PMC or mast cells immunomagnetically purified with mAb AA4 were used. An increase in degranulation of non-purified mast cells from infected animals was observed after incubation with histamine in vitro or when histamine was injected into the peritoneal cavity. When a purified mast cell population was used, this effect was no longer observed. Supernatants from spleen cells stimulated with histamine induced degranulation of purified mast cells, and again, this was potentiated with PMC from infected animals. However, when supernatants from peritoneal macrophages similarly stimulated were used, a reduction in the degranulation of PMC from infected animals was observed. Our results suggest that histamine may act as a regulator of mast cell degranulation, thus modulating inflammatory responses due to infection with certain parasites.     

血管活性肠多肽及降钙素基因相关肽对大鼠腹腔肥大细胞组胺释放的作用

目的:研究血管活性肠多肽(Vasoactive intestinal peptide,VIP)及降钙素基因相关肽(Calcitonin gene relatedpeptide,CGRP)对大鼠腹腔肥大细胞脱颗粒的诱导作用;了解神经多肽与肥大细胞的相互关系。方法:分离、纯化SD大鼠腹腔肥大细胞;应用不同浓度的VIP和CGRP作用于大鼠腹腔肥大细胞后,同位素放射液态闪烁法检测肥大细胞的组胺释放、45Ca摄入的变化;同时观察大鼠腹腔肥大细胞经5×10-6mol/L VIP受体抑制剂L-8-K处理后,对VIP诱导脱颗粒作用的影响。结果:5×10-6mol/L的VIP作用后大鼠腹腔肥大细胞组胺释放及45Ca摄入明显增加,并且这种变化与VIP呈剂量效应关系;CGRP对大鼠腹腔肥大细胞组胺释放无诱导作用;L-8-K作用后,肥大细胞对VIP的诱导活化作用无改变。结论:VIP可引起肥大细胞钙内流增加,进一步诱导肥大细胞脱颗粒、释放组胺等生物活性物质,产生生物学效应;这种作用是受体非依赖性的,且与VIP的分子构型有关。     

中华眼镜蛇毒金属蛋白酶诱导人肥大细胞释放组胺的作用

目的： 探索中华眼镜蛇毒金属蛋白酶(MT)对人肥大细胞释放组胺的诱导作用及其机制。 方法： 用肝素凝胶和Superdex75亲和力凝胶纯化MT。将手术切除的人肺、大肠和扁桃体组织在37 ℃用Ⅰ型胶原酶和Ⅰ型透明质酸酶消化, 悬浮细胞均匀地加入含MT、刺激剂或缓冲液的试管中,进行激发实验并用荧光显色法测量上清液的组胺水平。 结果： 纯化后的MT在SDS-PAGE上呈1条带。MT能诱导人肺、大肠和扁桃体肥大细胞发生剂量依赖性组胺释放。浓度低至0.03 mg/L时, MT就能诱导大肠肥大细胞显著性的组胺释放, 但对于肺和扁桃体的肥大细胞，MT的最低有效浓度分别为0.3 mg/L和30 mg/L。 MT诱导大肠和肺肥大细胞组胺释放，12 min时达高峰，而扁桃体肥大细胞的组胺释放则在8 min时达高峰。人大肠、肺和扁桃体肥大细胞经代谢抑制剂和百日咳毒素预处理后，MT诱导其释放组胺的作用明显减弱。缺乏外源性钙、镁离子时，MT诱导肥大细胞释放组胺的能力也明显减弱。 结论： MT可能通过G蛋白偶联受体途径激活人肥大细胞，从而参与毒蛇咬伤人体后所发生的病理生理过程。     

Histamine release induced by glucose (mannose)-specific lectins isolated from Brazilian beans. Comparison with concanavalin A

The histamine releasing properties of glucose (mannose)-specific lectins isolated from Brazilian beans was examined. TheCanavalia brasiliensis, Dioclea rostrata, andDioclea virgata lectins induced histamine release in rat peritoneal mast cells similar to concanavalin A. Less potency and efficacy was observed forCanavalia maritima, Dioclea guianensis, andDioclea violacea while very low activities were seen for the lectins fromDioclea grandiflora, Canavalia bonariensis, andCratylia floribunda.The histamine releasing effect was quenched by higher doses ofD. virgata lectin similar to what was reported for concanavalin A. This effect was abrogated by increasing the concentration of calcium in the incubating medium. As these above proteins have sites that bind calcium, higher doses of the lectins might withdraw the calcium which is essential for the mast cell secretion.     

慢性阻塞性肺部疾患时组胺及溶酶体酶的变化

本文测定了慢性阻塞性肺部疾患(COPD)患者及动物组胺及溶酶体酶的变化。结果表明,COPD者痰液中组胺含量明显增高,并与病情间有一定关系;SO_2吸入所致大鼠慢性支气管炎时,肺组胺含量明显增高,哮喘患者在疾病的急性发作期,血浆中组胺含量及β-葡萄糖醛酸酶(β-g)活性均明显增高,肺气肿者血浆β-g仅有轻度增高,而血浆组胺无显明变化。讨论了组胺及溶酶体酶在COPD发病中的意义。     

人肥大细胞的IgE依赖性组胺和类胰蛋白酶分泌

目的　利用人结肠组织的肥大细胞和肥大细胞激活的体外研究系统评价人肥大细胞释放类胰蛋白酶和组胺的能力及其机制。方法　经酶悬浮的人结肠肥大细胞与抗IgE抗体共同培养后记录浓度相关曲线和时间关系曲线。类胰蛋白酶用酶联免疫吸附试验的方法测量 ,而组胺则由一种以玻璃纤维为基础的荧光比色法测量。结果　抗IgE抗体可引起浓度相关性的组胺和类胰蛋白酶释放 ,最大组胺和类胰蛋白酶分泌量分别比基础分泌量超出 2 .7和 2 .5倍以上。抗IgE抗体的作用从加样后 10s开始 ,6min后达高峰并至少持续 15min。百日咳毒素和代谢抑制剂能够分别抑制抗IgE抗体引起的组胺和类胰蛋白酶释放。百日咳毒素还能够减少自发性类胰蛋白酶释放。结论　人结肠肥大细胞在受到抗IgE抗体刺激时具有平行释放类胰蛋白酶和组胺的能力 ,这个过程与肥大细胞膜G蛋白偶联受体的激活有关 ,并消耗能量。肥大细胞自发性释放组胺和类胰蛋白酶的功能可能是通过不同的机制实现的。     

Presence of SNAP-23 and syntaxin 4 in mouse and hamster peritoneal mast cells

Mast cells (MCs) play a crucial role in inflammatory reactions. Their presence and number in the peritoneal cavity is important to overcome and enhance resistance to peritoneal infection. When MCs are activated they release a variety of biological mediators from their granules, such as histamine, that contribute to the appropriate and rapid local immune response. Granular content is released using a process of compound exocytosis, also termed degranulation. SNAP-23 and syntaxin 4 are plasma membrane proteins involved in degranulation of rat MCs. Their presence, however, has not been studied in MCs of other rodent species. The aim of the present study was to investigate using immunocytochemistry whether SNAP-23 and syntaxin 4 are present in peritoneal MCs of the mouse and hamster. In addition, the diameter, percentage and histamine content of these cells were also analyzed. Our results demonstrate that SNAP-23 and syntaxin 4 are present in the mouse and hamster peritoneal MCs, suggesting that proteins involved in the secretory process in MCs are conserved among species. Likewise, we conclude that peritoneal MCs of mouse and hamster are heterogeneous in size, percentage and histamine content.     

Effects of somatostatin on ethanol-induced gastric erosions in the rat: Role of mast cells

Somatostatin (S) inhibits hemorrhagic gastric erosions produced by ethanol. In this study we compared the dose-dependent effects of linear (reduced) and cyclic (oxidized) S with respect to mast cell degranulation. The gastric mucosal injuries were more inhibited by linear S than by cyclic S. But linear S aggravated injury at a certain dose (10^–7 mol/rat). Mucosal mast cell degranulation correlated significantly with the area of hemorrhagic mucosal lesions (r=0.91). Both cytoprotection as well as aggravation potency of S may be connected to gastric mucosal mast cell activity in the rat.     

肥大细胞在支气管哮喘中的研究进展

支气管哮喘(哮喘)是呼吸系统的常见病和多发病,肥大细胞是其主要的反应细胞,目前关于肥大细胞在哮喘中作用的研究取得了新的进展,特别是肥大细胞蛋白酶及其抑制剂的深入研究和哮喘患者气道平滑肌束中肥大细胞数量明显增加并呈脱颗粒状态的发现,引起学者们极大的关注,本文将就肥大细胞在哮喘中的研究进展进行综述。     

Signaling pathway in nerve growth factor induced histamine release from rat mast cells

Objective and Design: We investigated a signal transduction pathway involved in NGF induced histamine secretion from mast cells. We compared this mechanism with the exocytosis induced by basic secretagogue compound 48/80.Materials and Methods: Isolated rat peritoneal mast cells were obtained from male Wistar rats. Histamine release was assayed spectrofl uorometrically.Results: We found that tyrosine kinase inhibitor genistein, phospholipase C (PLC) inhibitor U-73122, phosphatidylinositol 3-kinase (PI-3 kinase) inhibitor wortmannin, protein kinase C (PKC) inhibitors, staurosporine and GF109203X, but not MAP kinase inhibitors, SB203580 and PD98059, reduce histamine secretion in NGF provoked mast cell degranulation. In compound 48/80 mediated degranulation, we confi rmed only the involvement of tyrosine kinase and PLC, but not PI-3 kinase, PKC and MAP kinases.Conclusions: Our results indicate that release of histamine from mast cells after stimulation with NGF is regulated by tyrosine kinase, PLC, PI-3 kinase and PKC, but not by MAP kinases. This biochemical pathway differs from that provoked by compound 48/80.Received 16 February 2005; accepted by A. Falus 12 May 2005     

Serotonin content is elevated in the immune cells of histidine decarboxylase gene knock-out (HDCKO) mice. Focus on mast cells

Objective: Biogenic amines, histamine and serotonin are present in the granules and nucleus of mast cells. We wanted to study the presence, amount and localization of serotonin in mast cells and other cells of the immune system, under conditions of histamine deficiency caused by knock out of histamine decarboxylase gene (HDCKO). Methods: Wild type and histamine deficient HDCKO mice were studied for serotonin content of the immune cells (lymphocytes as well as the monocyte-granulocyte-mast cell group) using flow cytometry and confocal microscopy. Groups of mice were kept either on complete rodent chow or on a histamine-free diet for a month before the experiments. Results: The amount of serotonin was significantly higher in the KO animals, irrespective of the diet. Confocal microscopy demonstrated the presence of serotonin in the nucleus of mast cells in the wild type animals, while it was not present in the KO mice. Furthermore, in the cytoplasm (granules) of KO mast cells a bright fluorescence was observed in contrast to the pale fluorescence of wild animals. Conclusion: It seems likely that serotonin replaces the deficient histamine in the heparin-biogenic amine complex in the mast cell granules. Received 21 June 2006; returned for revision 17 July 2006; returned for final revision 22 September 2006; accepted by G. Wallace 17 October 2006     

哮喘与非哮喘中肥大细胞脱颗粒的研究

目的：研究哮喘与非哮喘中肥大细胞脱颗粒。方法：29名轻度哮喘患者参加了本项研究。支气管肺泡灌洗液（BALF）中的细胞经冲洗后，加入抗IgE抗体或CI或缓冲液的试管中进行激发试验。组织中肥大细胞的悬浮过程由Ⅰ型胶原酶和Ⅰ型透明质酸酶在37℃水浴箱中完成。BALF中的组胺采用酶联免疫反应试剂盒测定，而组织中的组胺则采用以玻璃纤维为基础的荧光方法来测定。结果：哮喘患者BALF中的肥大细胞对抗IgE抗体的敏感性要比非哮喘者至少敏感100倍；对CI刺激的敏感性与非哮喘者的相似。结论：哮喘患者BALF中肥大细胞对IgE依赖性刺激的敏感度增强。     

Expression of L-histidine decarboxylase in granules of elicited mouse polymorphonuclear leukocytes

Infiltrating polymorphonuclear leukocytes (PMN) in the peritoneal cavity were found to express L-histidine decarboxylase (HDC), the rate-limiting enzyme of histamine synthesis, in a csein-induced peritonitis model. Expression of HDC was detected in the elicited PMN, but not in the peripheral blood leukocytes. The peritoneal lavage fluids in this model were found to augment histamine synthesis in PMN isolated from the bone marrow. Rapid post-translational processing of HDC was observed in PMN, and the dominant form of HDC was the mature 53-kDa form, which was found to co-localize with a granule enzyme, matrix metalloproteinase-9 (MMP-9). Treatment of PMN with the phorbol ester PMA, which stimulates the release of MMP-9, did not liberate the granular HDC. Immunofluorescence studies using an anti-HDC antibody strongly suggested that HDC is bound to the cytosolic side of the granule membranes. These observations suggest that HDC is induced upon infiltration of PMN into the mouse peritoneal cavity and that histamine is synthesized by HDC attached to the granule membranes of PMN.     

Characteristics of the histamine release from hamster cheek pouch mast cells stimulated by lectins from Brazilian beans and concanavalin A

We have characterized the histamine releasing effects of lectins extracted from Brazilian beans, in comparison to concanavalin A, in hamster cheek pouch cell suspensions containing mast cells. The lectins fromDioclea virgata, Canavalia brasiliensis, andDioclea rostrata induce histamine release in a similar manner to concanavalin A, but appear to differ in potency and efficacy. The effects depended on the temperature, pH, and metabolic energy, demonstrating the non-cytotoxic nature of the histamine release. It is suggested that the lectins studied act by the same mechanism as concanavalin A (interacting with sugars in the antibodies bound to the mast cells), since high concentrations of glucose inhibit the histamine release. The lectins at high concentrations quench the histamine release. This suppression is reversed by increasing calcium concentration, suggesting that the lectins bind to the calcium that is essential for the secretion, thereby confirming and extending our previous data using the lectin fromDioclea virgata in rat peritoneal mast cells.accepted by W. Lorenz