通心络辅助尼可地尔对心肌梗死冠脉微循环障碍患者血清Tryptase、Copeptin表达的影响

目的 研究通心络辅助尼可地尔治疗心肌梗死冠脉微循环障碍(MI-CMVD)对类胰蛋白酶(Tryptase)、和肽素(Copeptin)表达的影响。方法 212例MI-CMVD患者随机分为对照组和观察组各106例。对照组予以尼可地尔进行治疗,观察组予以尼可地尔+通心络联合治疗。观察治疗前后两组血清Tryptase、Copeptin表达情况。结果 治疗后,观察组左心室射血分数(LVEF)明显高于对照组,而左心室收缩末期容积、左心室舒张末期容积明显低于对照组(均P<0.01);治疗后,与对照组相比,观察组全血黏度高切值、全血黏度低切值、血浆比黏度、血小板黏附率、肿瘤坏死因子(TNF)-α、白细胞介素(IL)-6、内皮素(ET)、血管紧张素(Ang)Ⅱ、Tryptase、Copeptin水平均明显降低,且观察组明显低于对照组(均P<0.01)。结论 经尼可地尔联合通心络治疗后可能通过降低炎性因子TNF-α、IL-6、ET、AngⅡ及血清Tryptase,提高血清Copeptin水平,改善患者心脏功能,进而促进冠脉微循环恢复。

Lactobacillus plantarum AR495 improves stress-induced irritable bowel syndrome in rats by targeting gut microbiota and Mast cell-PAR2-TRPV1 signaling pathway

Probiotics have great potential in regulating intestinal pain.In this study,the effects of Lactobacillus plantarum AR495 on the visceral sensitivity and gut microbiota of irritable bowel syndrome(IBS)rats were studied.The results showed that tryptase released after mast cell activation and degranulation plays a key role in visceral pain,and L.plantarum AR495 reduced the stimulation of colonic mast cells and the expression of protease-activated receptor 2(PAR2)and TRPV1 in dorsal root ganglia.Research further showed that supplementation with L.plantarum AR495 increased the level of short-chain fatty acids(SCFAs)and enhanced the barrier function of the colon.In addition,the microbiota analysis of the colon indicated that L.plantarum AR495 promoted the proliferation of Bifidobacterium and inhibited the proliferation of Lachnospiraceae,which alleviated the imbalance of the intestinal microbiota caused by IBS to a certain extent.In total,L.plantarum AR495 might reduce visceral sensitivity through the Mast cell-PAR2-TRPV1 signaling pathway by maintaining the homeostasis of the intestinal barrier.

Close relationship between mediators of inflammation and pancreatic cancer:Our experience

In this editorial,we focus specifically on the mechanisms by which pancreatic inflammation affects pancreatic cancer.Cancer of the pancreas remains one of the deadliest cancer types.The highest incidence and mortality rates of pancreatic cancer are found in developed countries.Trends of pancreatic cancer incidence and mortality vary considerably worldwide.A better understanding of the etiology and identification of the risk factors is essential for the primary prevention of this disease.Pancreatic tumors are characterized by a complex microenvironment that orchestrates metabolic alterations and supports a milieu of interactions among various cell types within this niche.In this editorial,we highlight the foundational studies that have driven our understanding of these processes.In our experimental center,we have carefully studied the mechanisms of that link pancreatic inflammation and pancreatic cancer.We focused on the role of mast cells(MCs).MCs contain pro-angiogenic factors,including tryptase,that are associated with increased angiogenesis in various tumors.In this editorial,we address the role of MCs in angiogenesis in both pancreatic ductal adenocarcinoma tissue and adjacent normal tissue.The assessment includes the density of c-Kit receptor-positive MCs,the density of tryptase-positive MCs,the area of tryptasepositive MCs,and angiogenesis in terms of microvascularization density.

Mast cell activation syndrome:An up-to-date review of literature

Mast cells are a subtype of white blood cells and are involved in the immune system.These cells contain many chemical substances called mediators,which are involved in the allergic response.The fact that mast cells play a role in many events that require urgent intervention,especially anaphylaxis,has led to a more detailed study of these cells.The diseases also caused by dysfunctions of mast cells have been examined in many circumstances.For instance,mast cell activation syndrome is known as an augmented number of cells due to decreased cell death,resulting in clinical symptoms affecting many systems.The main common symptoms include flushing,hypotension,urticaria,angioedema,headache,vomiting and diarrhea.Although the underlying mechanism is not yet clearly known,we aim to review the literature in a broad perspective and bring together the existing knowledge in the light of the literature due to the diversity of its involvement in the body and the fact that it is a little known syndrome.

腹部推拿调控Tryptase-PAR2-PKCε通路防治IBS-D内脏痛的机制研究

[目的]验证腹部推拿防治腹泻型肠易激综合征(IBS-D)模型大鼠内脏高敏感的效果,阐明其作用途径与机制。[方法]40只SD雄性大鼠,随机分为空白组、模型组、腹部推拿组、西药组,每组10只。采用母婴分离结合慢性应激法制备IBS-D大鼠模型。应用腹壁撤退评分评价干预效果。采用甲苯胺蓝染色观察结肠组织肥大细胞(MC)聚集数量及状态。利用免疫组化及蛋白质印迹法(Western blot)法分别检测胰蛋白酶(Tryptase)颗粒分布、结肠组织中蛋白酶激活受体2(PAR2)和蛋白激酶Cε(PKCε)蛋白表达。[结果]与模型组比较,腹部推拿组和西药组腹壁撤退反射评分(AWR)明显降低(P<0.05)。镜下显示,模型组MC形态不规则,计数及密度显著高于空白组;腹部推拿组、西药组与模型组相比,MC计数降低、密度减少(P<0.01)。免疫组化检测发现与模型组相比,腹部推拿组、西药组MC Tryptase颗粒分布明显降低(P<0.01);Western blot检测发现与模型组相比,腹部推拿组和西药组的PAR2、PKCε表达量均显著降低(P<0.01)。[结论]腹部推拿作用于腹部,可能通过活化肠道MC,调控其脱颗粒,降低Tryptase释放,并借助Tryptase-PAR2-PKCε通路,进而改善IBS-D模型大鼠肠道高敏感性作用机制。

Tryptase阳性细胞在移植后不同时间段排斥肾中的分布

目的 了解Tryptase阳性肥大细胞在肾移植后不同时间段的排斥肾组织中的分布规律。方法 采用抗Tryptase单抗免疫组化染色法与甲苯胺蓝特殊染色方法 ,对移植后 8d～ 7a手术切除的排斥肾进行了染色。结果 在移植后的各个时间段的排斥肾中均见到较正常肾明显偏多的肥大细胞 ,且随着移植时间的延长呈增长的趋势。其中移植后 7a以上组的肥大细胞明显高于 1～ 2a组和 5～ 6a组 (P <0 .0 1)。甲苯胺蓝染色结果与Tryptase免疫组化结果相一致 ,但Tryptase免疫组化方法更为敏感。结论 肥大细胞可能参与了肾移植的排斥反应 。

基质金属蛋白酶-2在人慢性牙周炎肥大细胞上表达的研究

目的观察基质金属蛋白酶-2(matrix metalloproteinase-2,MMP-2)在慢性牙周炎牙龈组织中肥大细胞上的表达,探讨MMP-2-tryptase双阳性肥大细胞(mast cells,MCs)在慢性牙周炎发病机制中的作用。方法将45例参试者依据慢性牙周炎的病变程度分成3组:健康对照组15例;轻度牙周炎组15例;重度牙周炎组15例。牙龈标本经10%福尔马林液固定48 h;制作牙龈组织连续切片,HE染色,光学显微镜下观察组织学改变;采用免疫荧光双染色法,荧光显微镜下观察牙龈组织中MMP-2-tryptase双阳性MCs的表达情况。结果与健康对照组相比,轻度和重度慢性牙周炎组牙龈组织MMP-2-tryptase双阳性MCs密度均显著升高(P<0.01);重度慢性牙周炎组牙龈组织MMP-2-tryptase双阳性MCs密度显著高于轻度牙周炎组(P<0.05)。结论慢性牙周炎牙龈组织MMP-2-tryptase双阳性MCs密度与牙周炎病变程度的趋势相一致,MMP-2-tryptase双阳性MCs在牙周炎的进展中可能有促进作用。

Vascular endothelial growth factor and tryptase changes after chemoembolization in hepatocarcinoma patients

AIM: To evaluate vascular endothelial growth factor(VEGF) and tryptase in hepatocellular cancer(HCC)before and after trans-arterial chemoembolization(TACE).METHODS: VEGF and tryptase serum concentrations were assessed from 71 unresectable HCC patients before and after hepatic TACE performed by binding DC-Beads?to doxorubicin. VEGF levels were examined for each serum sample using the Quantikine Human VEGF-enzyme-linked immuno-absorbent assay(ELISA),whereas tryptase serum concentrations were assessed for each serum sample by means of fluoro-enzyme immunoassay(FEIA) using the Uni-CAP100 tool.Differences between serum VEGF and tryptase values before and after TACE were evaluated using Student t test. Person's correlation was used to assess the degree of association between the two variables.RESULTS: VEGF levels and serum tryptase in HCCpatients before TACE had a mean value and standard deviation(SD) of 114.31 ± 79.58 pg/mL and 8.13± 3.61 μg/L, respectively. The mean levels and SD of VEGF levels and serum tryptase in HCC patients after TACE were 238.14 ± 109.41 pg/mL and 4.02 ±3.03 μg/L. The changes between the mean values of concentration of VEGF and tryptase before treatment and after treatment was statistically significant(P <0.000231 and P < 0.00124, by Wilcoxon-Mann-Whitney respectively). A significant correlation between VEGF levels before and after TACE and between tryptase levels before and after TACE was demonstrated(r =0.68, P = 0.003; r = 0.84, P = 0.000 respectively).CONCLUSION: Our pilot results suggest that the higher serum VEGF levels and the lower tryptase levels following TACE may be potential biomarkers changing in response to therapy.

Role of mast cell-mi R-490-5p in irritable bowel syndrome

AIM To determine the functional role of mi R-490-5p in mast cell proliferation and apoptosis,and in the mast cell tryptase/PAR-2 signal pathway.METHODS The 3rd generation of lentivirus vector systems containing enhanced green fluorescent protein(EGFP)(Ruisai Inc.,Shanghai,China),which acts as a reporter gene was used to construct the mmu-mi R-490-5p lentivirus expression vector p EGFP-antagomi R-490-5p,and the lentivirus vector p EGFP-negative was used as a negative control.The stably transfected mast cell line p815 was then constructed.GFP positive cells were successfully transfected cells.We determined the expression of mi R-490-5p in p815 mast cells before and after transfection using quantitative real-time PCR(q RT-PCR).In addition,after transduction with the lentivirus vectors,the role of mi R-490-5p in mast cell proliferation and apoptosis was investigated using the CCK-8 assay and flow cytometry,respectively.The m RNA levels of tryptase and PAR-2 were detected by q RT-PCR and the protein levels were detected by Western blot.RESULTS The inhibition of mi R-490-5p expression promoted apoptosis and inhibited proliferation of p815 mast cells.The m RNA levels of tryptase and PAR-2 were significantly increased after transfection comparedwith the control group,tryptase(P=0.721,normal vs null;P=0.001,si RNA vs normal;P=0.002,si RNA vs null)and PAR-2(P=0.027,si RNA vs null;P=0.353,normal vs null;P=0.105,si RNA vs normal).The protein levels of tryptase and PAR2 were slightly higher in the si RNA group than those in the control group,but the difference was not statistically significant(P>0.05).CONCLUSION mi R-490-5p plays a vital role in the pathogenesis of irritable bowel syndrome by affecting mast cell proliferation and apoptosis;with down-regulation of mi R-490-5p,the m RNA level of mast cell tryptase and PAR-2 increased,and the protein level increased,but the difference was not statistically significant.

Possible biological and translational significance of mast cells density in colorectal cancer

Mast cells(MCs), located ubiquitously near blood vessels, are descended from CD34+ hematopoietic stem cells. Initially, although their role has been well defined in hypersensitivity reactions, the discovery of their sharing in both innate and adaptive immunity has allowed to redefine their crucial interplay on the regulatory function between inflammatory and tumor cells through the release of mediators granule-associated(mainly tryptase and vascular endothelial growth factor). In particular, in several animal and human malignancies it has been well demonstrated that activated c-Kit receptor(c-KitR) and tryptase(an agonist of the proteinase-activated receptor-2) take pivotal part in tumor angiogenesis after the MCs activation, contributing to tumor cells invasion and metastasis. In this review, we focused on crucial MCs density(MCD) role in colorectal cancer(CRC) development and progression angiogenesis-mediated; then, we will analyze the principal studies that have focused on MCD as possible prognostic factor. Finally, we will consider a possible role of MCD as novel therapeutic target mainly by c-KitR tyrosine kinase inhibitors(imatinib, masitinib) and tryptase inhibitors(gabexate and nafamostat mesylate) with the aim to prevent CRC progression.

Mast cell tryptase and carboxypeptidase A expression in body fluid and gastrointestinal tract associated with drug-related fatal anaphylaxis

AIM: To investigate the expression of mast cell tryptase and carboxypeptidase A in drug-related fatal anaphylaxis.METHODS: The expression of mast cell tryptase and carboxypeptidase A in 15 autopsy cases of drugrelated fatal anaphylaxis and 20 normal autopsy cases were detected. First, the expression of mast cell tryptase was determined in stomach, jejunum, lung, heart, and larynx by immunofluorescence. Different tissues were removed and fixed in paraformaldehyde solution, then paraffin sections were prepared for immunofluorescence. Using specific mast cell tryptase and carboxypeptidase A antibodies, the expression of tryptase and carboxypeptidase A in gastroenterology tract and other tissues were observed using fluorescent microscopy. The postmortem serum and pericardial fluid were collected from drug-related fatal anaphylaxis and normal autopsy cases. The level of mast cell tryptase and carboxypeptidase A in postmortem serum and pericardial fluid were measured using fluor enzyme linked immunosorbent assay(FEIA) and enzyme linked immunosorbent assay(ELISA) assay. The expression of mast cell tryptase and carboxypeptidase A was analyzed in drug-related fatal anaphylaxis cases and compared to normal autopsy cases.RESULTS: The expression of carboxypeptidase A was less in the gastroenterology tract and other tissues from anaphylaxis-related death cadavers than normal controls. Immunofluorescence revealed that tryptase expression was significantly increased in multiple organs, especially the gastrointestinal tract, from anaphylaxis-related death cadavers compared to normal autopsy cases(46.67 ± 11.11 vs 4.88 ± 1.56 in stomach, 48.89 ± 11.02 vs 5.21 ± 1.34 in jejunum, 33.72 ± 5.76 vs 1.30 ± 1.02 in lung, 40.08 ± 7.56 vs 1.67 ± 1.03 in larynx, 7.11 ± 5.67 vs 1.10 ± 0.77 in heart, P < 0.05). Tryptase levels, as measured with FEIA, were significantly increased in both sera(43.50 ± 0.48 μg/L vs 5.40 ± 0.36 μg/L, P < 0.05) and pericardial fluid(28.64 ± 0.32 μg/L vs 4.60 ± 0.48 μg/L, P < 0.05) from the anaphylaxis group in comparison with the control group. As measured by ELISA, the concentration of carboxypeptidase A was also increased more than 2-fold in the anaphylaxis group compared to control(8.99 ± 3.91 ng/m L vs 3.25 ± 2.30 ng/m L in serum, 4.34 ± 2.41 ng/m L vs 1.43 ± 0.58 ng/m L in pericardial fluid, P < 0.05).CONCLUSION: Detection of both mast cell tryptase and carboxypeptidase A could improve the forensic identification of drug-related fatal anaphylaxis.

A concise, practical guide to diagnostic assessment for mast cell activation disease

As recognition of mast cell(MC) involvement in a range of chronic inflammatory disorders has increased, diagnosticians' suspicions of MC activation disease(MCAD) in their chronically mysteriously inflamed patients have similarly increased. It is now understood that the various forms of systemic mastocytosis- diseases of inappropriate activation and proliferation of MCs seemingly driven by a small set of rare, usually constitutively activating mutations in assorted MC regulatory elements-comprise merely the tip of the MCAD iceberg, whereas the far larger and far more clinically heterogeneous(and thus more difficult to recognize) bulk of the iceberg consists of assorted forms of MC activation syndrome(MCAS) which manifest little to no abnormal MC proliferation and may originate from a far more heterogeneous set of MC mutations. It is reasonable to suspect MCAD when symptoms and signs of MC activation are present and no other diagnosis better accounting for the full range of findings is present. Initial laboratory assessment should include not only routine blood counts and serum chemistries but also a serum total tryptase level, which helps direct further evaluation for mastocytosis vs MCAS. Appropriate tissue examinations are needed to diagnose mastocytosis, while elevated levels of relatively specific mast cell mediators are sought to support diagnosis of MCAS. Whether assessing for mastocytosis or MCAS, testing is fraught with potential pitfalls which can easily yield false negatives leading to erroneous rejection of diagnostic consideration of MCAD in spite of a clinical history highly consistent with MCAD. Efforts at accurate diagnosis of MCAD are worthwhile, as many patients then respond well to appropriately directed therapeutic efforts.

Effect of 1,25-dihydroxyvitamin D3 on mast cells tryptase in asthmatic guinea pigs

Objective:To explore the effect of 1,25-dihydroxyvitamin D3 on the mast cell tryptase(MCT) in asthmatic guinea pigs.Methods:A total of 60 male or female healthy guinea pigs were randomly divided into control group(group A),asthmatic group(group B).and 1,25-dihydroxyvitamin D3 group(group C),with 20 cases in each group.To establish asthmatic guinea pig models,1ml peanut oil was tilled into stomach in the morning in group A and group B.and 1 ml peanut oil with 1,25-dihydroxyvitamin D3 was filled into stomach in group C.Airway resistance(Re) of asthmatic guinea pigs was detected,and the bronchoalveolar lavage fluid(BALF) cells were counted.Lung tissue with HE and MCT immunohistochemical staining were used to observe the pathological changes in lung tissue and the distribution of MCT.Results:After injection of different concentration of acetylcholine chloride,the Re in group B and group C were increased significantly compared with group A(P<0.05):compared with group B.the Re in group C were decreased significantly(t=-5.385.-5.761.-6.184.-13.574.P<0.05):the total number of BALF cells and eosinophils were increased significantly in group B and C(t=19.618.9.598.10.854.5.388.P<0.05);compared with group B.the total number of BALF cells and eosinophils in group C was decreased significantly(t=-5.555.-5.392.P<0.05):the number of tryptase positive cells in group B was increased significantly than that in group A(t=21.312,P<0.05),and in addition to the alveolar septum and submucosa,the cells were also distributed around blood vessels and outside the cells:the number of tryptase positive cells in group C was decreased significantly compared with group B.and the difference was statistically significant(t=5.043.P<0.05).Conclusions:After the asthmatic guinea pigs arc treated with 1,25-dihydroxyvitamin D3,their BALF.Re.infiltration degree of inflammatory cells in the trachea and lung tissue and airway inflammatory reaction are reduced significantly.1,25-dihydroxyvitamin D3 has a certain inhibiting effect on the activation of mast cells and the release of MCT granules.

Validation of methods to assess potential biomarkers in pediatric patients with esophageal eosinophilia

AIM:To validate methods for determining mast cell density,extracellular major basic protein content,and presence of fibrosis in esophageal eosinophilia.METHODS:Twenty specimens with > 20 eosinophils/high-power field(hpf) classified as high eosinophil density(HE) and 20 specimens with < 5 eosinophils/hpf classified as low esophageal density(LE) were identified.All 40 specimens underwent immunohistochemical staining and trichrome staining.Mast cell density,extracellular major basic protein(MBP) density,and presence of subepithelial fibrosis were assessed in a standardized manner.All specimens were evaluated by two separate observers and by a single observer on two separate occasions to evaluate reproducibility of the methods.RESULTS:A strong inter-observer correlation was noted for both peak and mean mast cell counts(r = 0.725,P < 0.0001 and r = 0.823,P < 0.0001).A strong intraobserver correlation also was noted for both peak and mean mast cell counts(r = 0.752,P < 0.0001 and r =0.878,P < 0.0001).A very strong inter-observer correlation was noted for both peak(τ = 0.867,P < 0.0001)and mean extracellular MBP densities(r = 0.925,P <0.0001).A very strong intra-observer correlation was noted for both peak(τ = 0.875;P < 0.0001) and mean extracellular MBP densities(r = 0.956,P < 0.0001).Excellent inter-rater reliability was found for fibrosis(κ= 0.887).Mast cell and MBP densities,as well as presence of fibrosis,were significantly increased in HE vs LE.The HE group had significantly higher intraepithelial mast cell peak(29.35 ± 21.61 vs 12.45 ± 8.26,P =0.002) and mean(19.84 ± 15.81 vs 6.35 ± 4.5,P =0.001) densities than the LE group.The HE group had significantly higher peak extracellular MBP(2.35 ± 0.67vs 0.45 ± 0.61,P < 0.001) and mean extracellular MBP(1.95 ± 0.76 vs 0.20 ± 0.29,P < 0.0001) densities than the LE group.Seventy-three percent of patients with HE(11/15) had fibrosis,whereas only 10% of patients with LE(1/10) had fibrosis(P < 0.01).MBP performed the best in predicting classification of HE vs LE,with mean MBP demonstrating 100% sensitivity and95% specificity at the optimal cut point.CONCLUSION:This study provides methodology and proof-of-concept for future evaluation of these biomarkers for differentiating esophageal eosinophilic diseases such as reflux esophagitis and eosinophilic esophagitis.

类胰蛋白酶与变应性鼻炎－哮喘综合征

变应性鼻炎和哮喘均为呼吸道炎症，常在同一患者身上共存。自“同一气道，同一疾病”的观点提出后，越来越多的证据支持变应性鼻炎．哮喘综合征这个新的医学术语。其发病机制与肥大细胞关系密切，类胰蛋白酶几乎全由肥大细胞分泌，并以活性形式储存在肥大细胞的分泌颗粒中，可以作为肥大细胞储存及其活化的特异性标志。本文就类胰蛋白酶与变应性鼻炎一哮喘综合征的关系进行探讨。

Immune responses in fatalities involving opioids

In some cases of fatalities involving opioid use,the concentrations of detected opioids are not in the toxic range.Immune reactions can be triggered by opioid use,suggesting that immune response may be a factor in these cases.Autopsy cases from 2002–2012 were reviewed.Persons with physical,microscopic or serum evidence of allergic reactions and opioid use at autopsy were compared to persons who used opioids but had no such signs.Overall,49 persons were identified who had used opioids,of which five had evidence of immune response.A medical history of asthma was significantly more common in persons with signs of immune response(P=0.0244)and fatality(P=0.0085)compared to normals.A history of asthma is suggestive of susceptibility to immunologic reactions to opioids,and correlates strongly with the cause of death.

Glutamate triggers the expression of functional ionotropic and metabotropic glutamate receptors in mast cells

Mast cells are emerging as players in the communication between peripheral nerve endings and cells of the immune system.However,it is not clear the mechanism by which mast cells communicate with peripheral nerves.We previously found that mast cells located within healing tendons can express glutamate receptors,raising the possibility that mast cells may be sensitive to glutamate signaling.To evaluate this hypothesis,we stimulated primary mast cells with glutamate and showed that glutamate induced the profound upregulation of a panel of glutamate receptors of both the ionotropic type(NMDAR1,NMDAR2A,and NMDAR2B)and the metabotropic type(mGluR2 and mGluR7)at both the mRNA and protein levels.The binding of glutamate to glutamate receptors on the mast cell surface was confirmed.Further,glutamate had extensive effects on gene expression in the mast cells,including the upregulation of proinflammatory components such as IL-6 and CCL2.Glutamate also induced the upregulation of transcription factors,including Egr2,Egr3 and,in particular,FosB.The extensive induction of FosB was confirmed by immunofluorescence assessment.Glutamate receptor antagonists abrogated the responses of the mast cells to glutamate,supporting the supposition of a functional glutamate–glutamate receptor axis in mast cells.Finally,we provide in vivo evidence supporting a functional glutamate–glutamate receptor axis in the mast cells of injured tendons.Together,these findings establish glutamate as an effector of mast cell function,thereby introducing a novel principle for how cells in the immune system can communicate with nerve cells.

Up-regulation of interleukin-8 expressions induced by mast cell tryptase via protease activated receptor-2 in endothelial cell line

Background Protease activated receptor-2 is cleaved and activated by trypsin or mast cell tryptase and may play an important role in inflammation. However, it is unknown whetehr PAR-2 can mediate tryptase-induced inflammatory reaction. This study was conduct to investigate wheter PAR-2 could be the activated by mast cell tryptase and medicated the tryptase induced interleukin-8 expression in endothelial cells. Methods Protease activated receptor-2 expression was found in endothelial cell lines ECV304 cell by reverse transcription-polymerase chain reaction （RT-PCR） and Western blotting. Interleukin-8 stimulated by purified human mast cell tryptase was determined by RT-PCR and enzyme linked immunosorbent assay （ELISA）. Data were analysed by the S-N-K one-way ANOVA test. Results The present study shows that mRNA and protein of protease activated receptor-2 could be expressed in ECV304 cells, and tryptase upregulated the expression levels of both interleukin-8 mRNA and protein. The increased expression of interleukin-8 was inhibited by an antiprotease activated receptor-2 monoclonal antibody, SAM11. An additional band was observed by Western blotting after the incubation of ECV304 cells with tryptase for 2 hours, which suggested that protease activated receptor-2 was activated. Conclusion Protease activated receptor-2 can mediate the mast cell tryptase stimulated expression of interleukin-8 in ECV304 cell.

库拉索芦荟花抗过敏功效研究

通过研究库拉索芦荟花提取物诱导斑马鱼体内Tryptase分泌的水平,分析Compoud 48/80刺激产生Tryptase分泌量的抑制率,评估库拉索芦荟花提取物的抗过敏功效。研究结果表明,芦荟花提取物的体积分数分别为0.1%、0.2%和0.4%时,能够显著抑制Compoud 48/80刺激产生Tryptase分泌量,证明库拉索芦荟花提取物在化妆品中具备潜在的抗过敏功效。

Early development and functional properties of tryptase/chymase double-positive mast cells from human pluripotent stem cells

Mast cells (MCs) play a pivotal role in the hypersensitivity reaction by regulating the innate and adaptive immune responses. Humans have two types of MCs. The first type, termed MCTC, is found in the skin and other connective tissues and expresses both tryptase and chymase, while the second, termed MCT, which only expresses tryptase, is found primarily in the mucosa. MCs induced from human adult-type CD34+ cells are reported to be of the MCT type, but the development of MCs during embryonic/fetal stages is largely unknown. Using an efficient coculture system, we identified that a CD34+c-kit+ cell population, which appeared prior to the emergence of CD34+CD45+ hematopoietic stem and progenitor cells (HSPCs), stimulated robust production of pure Tryptase+Chymase+ MCs (MCTCs). Single-cell analysis revealed dual development directions of CD34+c-kit+ progenitors, with one lineage developing into erythro-myeloid progenitors (EMP) and the other lineage developing into HSPC. Interestingly, MCTCs derived from early CD34+c-kit+ cells exhibited strong histamine release and immune response functions. Particularly, robust release of IL-17 suggested that these early developing tissue-type MCTCs could play a central role in tumor immunity. These findings could help elucidate the mechanisms controlling early development of MCTCs and have significant therapeutic implications.