肥大细胞与肝纤维化

肝纤维化是各种慢性肝病发展为肝硬化的中间环节.肝纤维化的发病机制尚未完全清楚,但肝星状细胞激活并转化为肌成纤维细胞和成纤维细胞,通常被认为是肝纤维化发生发展的核心环节.肝损伤是引发肝纤维化的始动环节.     

The mast cell and bone

The mast cell, which contains many potent bioactive substances, by its very location must have an effect on bone metabolism in health and disease. In this article, the early questions about mast cells in bone raised by Urist and McLean almost thirty years ago are only partially answered, but the work continues to stimulate new experimental and clinical research on the function of mast cells.     

Tubulointerstitial mast cell infiltration in glomerulonephritis

Mast cells are involved in chronic inflammation and tissue fibrosis. To determine whether these cells are also involved in tubulointerstitial injury in glomerulonephritis, we assayed mast cell infiltration in the kidneys of 107 patients with primary or secondary glomerulonephritis. Using a monoclonal antihuman tryptase antibody, we detected mast cells in the renal cortical tubulointerstitium, the periglomerular areas, and the medullary interstitium, but not in glomeruli. Renal cortical tubulointerstitial mast cells, including periglomerular area, were estimated as 0.8+/-1.6 cells/mm2 in minimal change nephrotic syndrome (n=7), 1.5+/-0.7 cells/mm2 in minor glomerular abnormalities without nephrotic syndrome (n=7), 6.5+/-7.7 cells/mm2 in membranous nephropathy(n=10), 12.9+/-15.5 cells/mm2 in lupus nephritis (n=15), 13.4+/-8.3 cells/mm2 in focal segmental glomerular sclerosis (n=6), 18.5+/-21.1 cells/mm2 in ANCA-related nephropathy (n=5), 19.8+/-14.2 cells/mm2 in membranoproliferative glomerulonephritis (n=5), 21.3+/-17.7 cells/mm2 in immunoglobulin A (IgA) nephropathy (n=42), and 33.0+/-33.8 cells/mm2 in diabetic nephropathy (n=10). Except for patients with the rapidly progressive glomerulonephritic syndrome (RPGN), the number of infiltrating mast cells significantly correlated with the serum concentration of creatinine at the time of renal biopsy (r=0.59; P < 0.0001) and with the intensity of tubulointerstitial injury as measured by leukocyte infiltration (r=0.72; P < 0.0001) and fibrosis (r=0.75; P < 0.0001). In contrast, mast cell infiltration did not correlate with urinary protein excretion. In relation to serum creatinine concentration, the number of mast cells was fewer in patients with RPGN than in those with chronic glomerulonephritis. These data suggest that mast cells may contribute to the renal deterioration in glomerulonephritis by inducing chronic tubulointerstitial injury.     

Cutaneous mast cell tumor and mastocytosis in a black-masked lovebird (Agapornis personata)

A 12-year-old female black-masked lovebird (Agapornis personata) with a cobalt color mutation was presented for self-mutilation of a mass located on the right lateral neck. Cytologic evaluation of the soft tissue mass revealed a predominance of poorly stained mast cells with metachromatic intracytoplasmic granules. The presumptive diagnosis was cutaneous mast cell tumor. Clinical evaluation, results of a complete blood cell count and biochemical analysis, and radiographs did not reveal systemic manifestation of mast cell disease. The mass was surgically resected, but surgical margins were limited because of the location of the mass and the small size of the patient. The lovebird died the day after surgery. Gross postmortem examination revealed splenomegaly, multifocal pinpoint white nodules throughout the liver parenchyma, severe thickening and yellow coloration of the great vessels, and pale pink swelling of the caudal right kidney. Histopathologic analysis of the resected mass revealed sheets of round cells that contain metachromatic granules, defined as neoplastic mast cells, within a fine fibrovascular stroma. Similar neoplastic cells were seen in the right kidney, hepatic sinusoids, splenic pulp, periovarian connective tissue, and bone marrow. The histopathologic diagnosis was a cutaneous mast cell tumor and disseminated mast cell disease, or mastocytosis. To the authors' knowledge, this is the first reported case of a cutaneous mast cell tumor and mastocytosis in a psittacine bird.     

Enhanced expression of mast cell growth factor and mast cell activation in the bladder following the resolution of trinitrobenzenesulfonic acid (TNBS) colitis in female rats

AIMS: Chronic pelvic pain disorders often overlap. We have shown that acute colonic irritation can produce acute irritative micturition patterns and acutely sensitize bladder afferent responses to mechanical and chemical stimuli. We hypothesize that with time, colonic irritation can lead to neurogenic changes in the bladder and the development of chronic bladder sensitization. METHODS: Micturition patterns were measured in rats 60-90 days after the induction of trinitrobenzenesulfonic acid (TNBS) colitis in the resolution phase of this model. Total and activated mast cells (MCs) were quantified in the bladder, while mRNA levels of stem cell factor (SCF; a.k.a. MC growth factor) and nerve growth factor (NGF; a MC and nociceptive C-fiber stimulator) were quantified in the bladder and L6-S1 dorsal root ganglia (DRG). RESULTS: Following intra-rectal TNBS, voiding volume was reduced (P < 0.005), while voiding frequency was increased (P < 0.05), both by approximately 50%. Furthermore, both the percentage and density of activated bladder MCs were significantly elevated (P < 0.05), although total MC counts were not statistically increased. At the molecular level, urinary bladder SCF expression increased twofold (P < 0.005), as did NGF (P < 0.01), while L6-S1 DRG levels were not significantly elevated. CONCLUSIONS: Chronic cystitis in the rat as evidenced by changes in micturition patterns and the recruitment of activated MCs can occur during the resolution phase of TNBS colitis. These changes, of which MCs may play an important role, appear to be maintained over time and may occur via stimulation of convergent pelvic afferent input resulting in the upregulation of neurotrophic factors in the target organ.     

Mast cell chymase expression and mast cell phenotypes in human rejected kidneys

BACKGROUND: Mast cells (MCs) are known to participate in various types of chronic disease, but their role in chronic renal rejection is poorly understood. Recently, distinct phenotypes of MCs have been described in humans by the demonstration of one protease, chymase. Hence, we questioned whether chymase in MCs could play a role in the pathogenesis of renal rejection in humans. METHODS: We investigated MC chymase expression and MC phenotypes, using immunohistochemical single- and double-staining techniques, in nephrectomy (N = 13) and biopsy (N = 8) specimens of human rejected kidneys. Tissue chymase levels were determined by enzymatic assay for chymase activity. We also examined the association between MC chymase expression and the degree of interstitial fibrosis in these renal allografts. RESULTS: Based on chymase positivity, rejected kidneys were divided into two groups, a chymase-negative [Chy(-)] group and a chymase-positive [Chy(+)] group. Quantitative analysis showed that the number of chymase-positive MCs and tissue chymase levels were significantly higher in the Chy(+) group than in the Chy(-) group. Furthermore, the interstitial fibrotic area in the Chy(+) group was significantly larger than that in the Chy(-) group. Immunodouble staining analysis also demonstrated that a new MC phenotype, positive for chymase but negative for tryptase, was present in the human rejected kidney. CONCLUSIONS: These results show that increased expression of chymase in MCs is related to the severity of interstitial fibrosis in human rejected kidneys.     

肥大细胞类胰蛋白酶在病理性瘢痕中的表达研究

目的 研究肥大细胞类胰蛋白酶(mast cell tryptase,MCT)在病理性瘢痕中的表达及分布情况,探讨MCT基因在瘢痕疙瘩、增生性瘢痕及正常皮肤中是否存在差别.方法 采集未经治疗的瘢痕疙瘩、增生性瘢痕及正常皮肤各20例,应用免疫荧光组化对MCT的表达进行定位,应用实时荧光相对定量PCR进行mRNA基因水平的相对定量分析.结果 MCT主要集中在瘢痕组织的胶原纤维柬之间,以瘢痕组织浅层分布较多;实时荧光PCR相对定量结果显示MCT基因在瘢痕疙瘩中表达高于增生性瘢痕和皮肤(P<0.01),瘢痕疙瘩中MCT基因表达量约为增生性瘢痕的2.5倍,皮肤的5.4倍.结论 MCT在瘢痕的形成中可能起一定的作用.     

肥大细胞在增生性瘢痕组织中的分布特征及其意义

目的探讨肥大细胞(MC)在增生性瘢痕(HS)组织中的分布特征及其促纤维化作用.方法结合MC超微结构改变,采用甲苯胺蓝和MC类胰蛋白酶(MCT)免疫组织化学染色方法,观察67例面颈部烧伤后HS患者皮肤标本和10例正常人皮肤标本,比较MC分布特征与病理性胶原结构形成的关系.结果在早期瘢痕(≤6个月)组织中可见胞体肥大和MCT阳性颗粒丰富的MC,其周围基质内也有MCT阳性物质分布,超微结构显示颗粒内容物丰富的MC与FB之间密切接触,可见胞膜融合和颗粒转移相;随着瘢痕增生和成熟,MC密度显著下降(P＜0.05～0.001),其胞膜突起和颗粒内容物明显减少,大多分布于胶原纤维间和胶原结节的边缘.结论MC动态分布特征和活跃的生物学行为显示其参与了HS胶原结构的形成.     

Secretory meningioma: immunohistochemical findings and evaluation of mast cell infiltration

Secretory meningiomas constitute a relatively rare subtype of meningiomas, accounting for only 1.1% at our institution, with a 6:1 predominance of female patients. This study aimed to obtain more information about the immunohistochemical characteristics of this histological entity, and to analyse the effects of histological factors such as the presence of mast cells on the radiological evidence of surrounding tumour oedema that frequently occurred in this subtype of meningioma. Fourteen cases of secretory meningioma were examined. Relevant clinical information was obtained from the patient files. Peritumoural oedema was determined either by CT or MRI scans and graded as small, moderate and severe. In order to perform the quantitative evaluation of mast cells in secretory meningiomas in a comparison with other meningiomas, 14 non-secretory meningiomas were randomly selected and used as a control group. The immunohistochemical staining of carcinoembryonic antigen was positive within the secretory droplets and the cells surrounding them in all cases. Ki 67 (MIB 1) proliferative index mean values were 2.4%, indicating low expression in all secretory meningiomas. Moreover, from our statistical analysis, there is no clear-cut pattern of various types of cytokeratins emerging in secretory meningiomas. The secretory meningiomas were characterized by a significantly increased number of mast cells as compared with non-secretory meningiomas of different grades. As the present clinical findings and laboratory results could not confirm a correlation between mast cell density and radiological evidence of oedema, further studies of mediators are warranted.     

Splenectomy in the management of systemic mast cell disease

The records of 26 patients with systemic mast cell disease (SMCD) treated during the past decade at the National Institutes of Health were reviewed to determine the role of splenectomy in the management of SMCD. Seventeen (65%) patients had indolent SMCD, manifested primarily by urticaria pigmentosa and mast cell infiltration of the skin, bone marrow, or gastrointestinal tract. None of these patients underwent splenectomy. These patients required only symptomatic therapy. Nine (35%) patients, including those with associated hematologic disorders and those with a lymphoma-like illness termed lymphadenopathic mastocytosis with eosinophilia, had aggressive SMCD. Five of nine patients with aggressive SMCD underwent splenectomy. Of the five patients with splenectomy, three were alive at the time of this report, whereas none of the four who did not have a splenectomy was still alive. Length of survival without splenectomy was 26 months. With splenectomy, length of survival at the time of this report was 34 months. Patients without splenectomy died of bleeding caused by severe thrombocytopenia. Patients with splenectomy appeared better able to tolerate chemotherapy. We thus conclude that while splenectomy is of no value in the management of indolent mastocytosis, it should be considered in patients with aggressive SMCD.     

Inhibitory effects of intravenous anesthetics on mast cell function

Mast cells play a protective role in the inflammation and auto-tissue injury. The impairment of mast cell function may influence defense against infection. We investigated the effect of four IV anesthetics (thiopental, midazolam, ketamine, and propofol) on the chemotaxis and exocytosis of mast cells. Canine mast cell chemotaxis was measured by the Boyden's blindwell chamber technique using 100 microg/mL of substance P as a stimulator. We measured mast cell exocytosis by measuring released histamine from mast cells using substance P or gamma-monomeric IgG-mediated crosslinking as a stimulator. Thiopental, midazolam, and propofol exerted a dose-dependent inhibitory effect on mast cell chemotaxis. Ketamine, midazolam, and propofol had a dose-dependent inhibitory effect on mast cell exocytosis. In conclusion, midazolam and propofol inhibited both chemotaxis and exocytosis of mast cells, while thiopental only inhibited chemotaxis, and ketamine only inhibited exocytosis. IMPLICATIONS: Mast cells play an important role in the antibacterial host-defense mechanism. Thiopental, midazolam, and propofol exerted a dose-dependent inhibitory effect on mast cell chemotaxis. Ketamine, midazolam, and propofol had a dose-dependent inhibitory effect on mast cell exocytosis. The impairment of mast cell function by IV anesthetics may influence the defense against infection.     

肾癌预后与浸润肥大细胞、淋巴细胞和P53表达的关系

对４３例肾癌中长期存活（＞５年）组２１例和短期转移组２２例分别进行了癌间质中肥大细胞数量、淋巴细胞反应程度以及Ｐ５３蛋白表达研究。结果证明长存组肾癌交界区及中心区肥大细胞计数明显高于转移组（Ｐ＜００１），且交界区计数高于中心区。长存组癌间质淋巴细胞反应强于转移组（Ｐ＜００１），其反应程度与肥大细胞计数有明显正相关性。Ｐ５３蛋白表达在两组间无显著性差异（Ｐ＞００５）。前两者反应强时，患者生存期延长、预后亦好。提示癌间质肥大细胞数量，淋巴细胞反应可作为临床判断肾癌恶性程度及预后的简易的客观量化标准     

Effects of sugammadex and rocuronium mast cell number and degranulation in rat liver

We investigated the effect of rocuronium‐ and sugammadex‐induced mast cell increase and degranulation in rat portal triads. Forty‐two rats, in six groups, received either rocuronium 1 mg.kg^?1; sugammadex 15 mg.kg^?1; sugammadex 100 mg.kg^?1; rocuronium 1 mg.kg^?1 and 5 min later, sugammadex 15 mg.kg^?1; rocuronium 1 mg.kg^?1 and 5 min later, sugammadex 100 mg.kg^?1; or isotonic saline. Total mast cell numbers were significantly higher with rocuronium only, than in all other groups (p < 0.003), although in all active groups, the number was greater than the control. Total mast cell number was significantly higher with rocuronium and low‐dose sugammadex compared with low‐dose sugammadex only. The number of tryptase‐positive mast cells with rocuronium only was significantly higher than in all other groups (p < 0.003). Tryptase‐positive mast cell numbers in both groups receiving both rocuronium and sugammadex were significantly higher compared with both groups receiving sugammadex only. Rocuronium increased mast cell numbers, and degranulation was mitigated by sugammadex. These results suggest that sugammadex may be beneficial in treatment of rocuronium‐induced anaphylaxis.     

内毒素对大鼠肥大细胞脱颗粒释放肿瘤坏死因子-α的影响

目的 通过体外分离培养大鼠腹腔肥大细胞(RPMC),进而探讨内毒素(ETX)对RPMC脱颗粒释放TNF-α的影响.方法 将悬浮培养的RPMC分为5组:(1)无ETX处理组;(2) 0.5 μg/ml ETX处理组;(3) 1 μg/ml ETX处理组;(4) 2 μg/mL ETX处理组;(5)4 μg/mL ETX处理组.37 ℃孵育2 h ,收集RPMC上清,用放射免疫分析法测定培养上清中TNF-α的水平.结果 不同浓度ETX处理组与无ETX处理组相比RPMC脱颗粒现象明显;不同浓度ETX处理组刺激RPMC释放TNF-α的量均高于无ETX处理组(P＜0.05),与ETX剂量依赖性不明显(P＞0.05),给予1 μg/mL ETX处理时TNF-α的释放量最高.结论 ETX体外可刺激RPMC脱颗粒,释放TNF-α,但与ETX剂量依赖性不明显,由此可推测内毒素可通过刺激RPMC释放TNF-α参与肝纤维化的发生发展.     

Mechanism of mast cell adhesion to human tenocytes in vitro

Mast cells and fibroblasts are two key players involved in many fibrotic and degenerative disorders. In the present study we examined the nature of binding interactions between human mast cells and tendon fibroblasts (tenocytes). In the mast cell‐fibroblast co‐culture model, mast cells were shown to spontaneously bind to tenocytes, in a process that was partially mediated by α5β1 integrin receptors. The same receptors on mast cells significantly mediated binding of these cells to tissue culture plates in the presence of tenocyte‐conditioned media; the tenocyte‐derived fibronectin in the media was shown to also play a major role in these binding activities. Upon binding to tenocytes or tissue culture plates, mast cells acquired an elongated phenotype, which was dependent on α5β1 integrin and tenocyte fibronectin. Additionally, tenocyte‐derived fibronectin significantly enhanced mRNA expression of the adhesion molecule, THY1, by mast cells. Our data suggests that α5β1 integrin mediates binding of mast cells to human tenocyte and to tenocyte‐derived ECM proteins, in particular fibronectin. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:9–16, 2015.

     

Role of mast cell tryptase in renal interstitial fibrosis.

Renal interstitial fibrosis is characterized by increased proliferation of fibroblasts and excessive accumulation of extracellular matrix. Mast cell tryptase has been implicated in the development of tissue fibrosis in skin and lungs. However, the significance of mast cell tryptase in human renal diseases has not been investigated. The potential role of mast cell-derived tryptase in the development of renal fibrosis was studied using immunohistochemical techniques and cultured human renal fibroblast cell lines. Semiquantitative immunostaining analysis of samples from 70 patients with several renal diseases, including IgA glomerulonephritis (GN) (n = 30), non-IgA GN (n = 5), membranous GN (n = 5), focal segmental glomerulosclerosis (n = 4), minor glomerular abnormalities (n = 5), lupus nephritis (n = 3), and acute or chronic tubulointerstitial nephritis (n = 18), revealed that the degree of renal interstitial fibrosis was well correlated with the number of infiltrating tryptase-positive mast cells (P < 0.01). Mast cells could not be detected in damaged glomeruli in any form of renal disease. [(3)H]Thymidine uptake experiments demonstrated that DNA synthesis by cultured renal fibroblasts was increased with the concentration of tryptase (0.5 to 5 nM) coincubated with heparin and was suppressed by coincubation with the protease inhibitors leupeptin and benzamidine hydrochloride. Tryptase alone also increased DNA synthesis by fibroblasts but exhibited less effectiveness, compared with the combination of tryptase and heparin. Conversely, heparin alone suppressed DNA synthesis by fibroblasts. Metabolic [(35)S]methionine-labeling experiments with cultured renal fibroblasts indicated that tryptase increased the synthesis of fibronectin and collagen type I, in a dose-dependent manner. These findings suggest that mast cell tryptase plays a role in the proliferation and extracellular matrix protein production of renal interstitial fibroblasts and thus contributes to the development of renal interstitial fibrosis.