Inhibition of tumour necrosis factor-alpha (TNF-alpha) release from mast cells by the anti-inflammatory drugs, sodium cromoglycate and nedocromil sodium.

TNF-alpha is a cytokine thought to be involved in the pathogenesis of asthma and in several other inflammatory conditions. Given recent evidence that mast cells (MC) are an important source of TNF-alpha, we investigated the effects of two anti-inflammatory drugs, nedocromil sodium (NED) and sodium cromoglycate (SCG), on rat MC-derived TNF-alpha. We established that at least 2 h pretreatment with NED or SCG followed by washing was required to inhibit TNF-alpha-dependent cytotoxicity by rat peritoneal MC (PMC). A maximum inhibition of TNF-alpha occurred after 6 h treatment. The inhibitory effect of NED and SCG (10(-5)-10(-3)M) was concentration-dependent (20-37% for NED and 16-37% for SCG). The time-course analysis and the use of cycloheximide, an inhibitor of protein synthesis, provided strong evidence that new protein synthesis by the MC is required for this inhibitory effect. Furthermore, 24 h treatment with 1 mM NED inhibited the levels of mRNA for TNF-alpha by 59-83%. In addition to the effect on TNF-alpha-dependent cytotoxicity by MC, 20 min pretreatment with 10(-4) M NED and SCG inhibited antigen-stimulated TNF-alpha release (6h) by 42% and 48%, respectively. Interestingly, the functionally distinct intestinal mucosal MC (IMMC) is unresponsive to these drugs with regard to histamine secretion. However, as with PMC, 2h pretreatment with NED or SCG inhibited TNF-alpha-dependent cytotoxicity by IMMC. These effects may be important in the action of these drugs in vivo in the late phase reaction in asthma or other inflammatory conditions.     

Effects of nedocromil sodium (Tilade®) on the activation of human eosinophils and neutrophils and the release of histamine from mast cells

The ability of nedocromil sodium, a new anti-inflammatory agent for the treatment of asthma, to inhibit activation of human eosinophils and neutrophils in vitro, has been studied using an adherence reaction (the "rosette" technique) as well as a cytotoxicity assay. We have also investigated the capacity of nedocromil sodium to inhibit IgE-dependent histamine release from human lung mast cells. The drug was a potent inhibitor (IC50 approx 5 x 10(-9)M) of fMLP-induced enhancement of eosinophil and neutrophil complement (C3b) and IgG (Fc) rosettes. There was also a comparable inhibition of enhancement, by fMLP, of eosinophil and neutrophil cytotoxicity (for complement-coated schistosomula of Schistosoma mansoni). Although nedocromil sodium also inhibited histamine release from human lung mast cells in a dose-dependent fashion its activity was relatively weak (IC30 5 x 10(-6)M) compared to its effect on granulocytes. These experiments support the view that the principal mode of action of nedocromil sodium is its capacity to inhibit the activation of inflammatory cells.     

The increased number of epithelial mast cells in nasal polyps and adjacent turbinates is not allergy-dependent

Respiratory epithelial mast cells are an expression of airway inflammatory processes. Nasal epithelial mast cells are known to be increased in allergic rhinitis and have now been examined in patients with nasal polyps. Metachromatic cell counts (mean +/- standard error) expressed as the sum of large mast cells, atypical mast cells and basophils in epithelial scrapings of the inferior turbinates, assessed after Carnoy's fixation and toluidine blue staining (pH 0.5), were 37.5 +/- 29 in non-allergic normal control subjects (n = 11), 435 +/- 130 in polyp patients who were allergic (n = 18), and 699 +/- 267 in polyp patients who were not allergic (n = 8). Metachromatic cell counts in epithelial scrapings obtained in vivo from nasal polyps of allergic patients (n = 8) were 1769 +/- 962, and 2308 +/- 1544 from polyps of non-allergic patients (n = 5); metachromatic counts were 2089 +/- 633 in epithelial scrapings from excised polyps of allergic patients (n = 14) and 2214 +/- 640 from polyps of non-allergic patients (n = 13). It is concluded that the number of metachromatic cells in the epithelium of nasal polyps and the adjacent nasal mucosa is elevated compared with normal nasal epithelium and the increased number does not depend upon allergy.     

Inhibition of nasal polyp mast cell and eosinophil activation by desloratadine

Nasal polyp tissue which contains mast cells and eosinophils is similar to the inflamed airway mucosa in cellular composition and mediator content. This investigation assessed the effect of desloratadine (DL), on activation of cells in nasal polyp tissue. Polyps were obtained from 22 patients with chronic rhinosinusitis [nine aspirin acetylosalitic acid (ASA)-sensitive and 13 ASA-tolerant]. Polyp tissue was dispersed by digestion, and preincubated with DL and incubated with anti-immunoglobulin E (IgE) or calcium ionophore. LTC4, eosinophil cationic protein (ECP) and tryptase concentrations in supernatants were measured by immunoassays. Desloratadine (1, 10 and 50 microM) inhibited calcium ionophore-induced LTC4 release by a mean of 29%, 50% and 63% respectively, and anti-IgE-induced LTC4 release by a mean of 27%, 35% and 39% respectively. Calcium ionophore-induced tryptase release was inhibited 60% and 69% by 10 and 50 microM of DL, respectively, and anti-IgE-induced tryptase release was inhibited 33%, 47% and 66% for 1, 10 and 50 microM of DL. Desloratadine 10 microM and 50 microM inhibited ECP release by and 45% and 48% respectively. Polyp tissue from ASA-sensitive patients when compared with ASA-tolerant patients released at baseline significantly more ECP (medians 120.0 microg/ml, range: 69.0-182.0 vs 63.4 microg/ml, range: 3.7-172.0; P <0.05), but similar amounts of tryptase and LTC4. This study demonstrated that DL inhibits activation of both eosinophils and mast cells derived from a site of airway mucosal inflammation.     

Neutrophils enhance eosinophil migration across monolayers of lung epithelial cells

During the late-phase asthmatic response eosinophils and neutrophils infiltrate the lungs and cause severe damage. In this study, we investigated in vitro the migration of eosinophils, in the absence and presence of neutrophils, across a monolayer of lung H292 epithelial cells. The migration of eosinophils towards the complement fragment 5a (C5a) was increased when neutrophils were added to the upper compartment of the Transwells, and decreased when neutrophils were added to the lower compartment. Moreover, neutrophils exclusively stimulated eosinophil migration towards C5a, and not towards other chemoattractants such as RANTES, IL-8 or PAF. Neutrophils and eosinophils differed in that neutrophils, but not eosinophils, rapidly inactivated C5a, suggesting that neutrophils in the upper compartment remove part of the active C5a that has diffused into the upper compartment. Indeed, we found that the addition of other C5a-degrading agents, such as human serum or carboxypeptidase B, also enhanced eosinophil migration when added to the upper compartment and decreased migration when added to the lower compartment. Taken together, these results indicate that the presence of neutrophils influences the migratory behaviour of eosinophils in vitro. The neutrophils presumably maintain a proper C5a chemotactic gradient in the transmigration model, which results in enhanced eosinophil chemotaxis.     

Effect of desloratadine on epithelial cell granulocyte-macrophage colony-stimulating factor secretion and eosinophil survival

BACKGROUND: Second-generation antihistamines are H(1) receptor antagonists and may have additional anti-inflammatory effects. OBJECTIVE: The aims of the study were to evaluate the effect of desloratadine (DL) on cytokine secretion by epithelial cells from both nasal mucosa (NM) and polyps (NP), and on eosinophil survival primed by epithelial cell secretions. METHODS: Epithelial cells were cultured and stimulated with fetal bovine serum (FBS), IL-1beta or TNF-alpha with and without DL for 24 h. Culture supernatant cytokines concentration were measured by ELISA. Peripheral blood eosinophils were incubated with human epithelial cell conditioned media (HECM) and DL. Eosinophil survival was assessed by Trypan blue dye exclusion. Results are expressed as mean+/-SEM of cytokine concentration (pg/mL) or eosinophil survival index (%). RESULTS: FBS increased granulocyte-macrophage colony-stimulating factor (GM-CSF), vascular endothelial growth factor (VEGF), IL-6, IL-8, and TGF-beta(1) secretion in epithelial cell cultures from both NM and NP. Only GM-CSF secretion was significantly (P<0.05) inhibited by a dose-response of DL compared with positive controls, in both NM (10(-5) m: 125+/-36 pg/mL, 10(-6) m: 95+/-22 pg/mL vs. control: 256+/-91 pg/mL, n=6) and NP (10(-5) m: 80+/-29 pg/mL, 10(-6) m: 109+/-45 pg/mL vs. control: 333+/-212 pg/mL, n=6). DL also showed an inhibitory effect on HECM-induced eosinophil survival from both NM and NP. At 72 h, DL significantly (P<0.01) inhibited eosinophil survival induced by HECM from NM (10(-5) m: 19.9+/-5.5%, n=9; 10(-6) m: 28.7+/-7.7%, n=9) and NP (10(-5) m: 6.2+/-2.8%, n=11) compared with HECM alone (NM: 42.1+/-7.3%; NP: 45.3+/-8.1%). CONCLUSION: The inhibitory effects of DL on epithelial cell GM-CSF secretion and on eosinophil survival induced by epithelial cell secretions, suggest that this H(1) antagonist may regulate eosinophil inflammation in upper airways.     

Double-blind, randomized, placebo-controlled trial of effect of nedocromil sodium on clinical and inflammatory parameters of asthma in children allergic to dust mite

BACKGROUND: The purpose of this study was to determine the clinical effect of nedocromil sodium and its relationship with serum levels of inflammatory mediators by monitoring lung function and noninvasive markers of airway inflammation, such as eosinophil blood counts; serum ECP, sIL-2R, IL-4 and sICAM; and total IgE. Anti-inflammatory medications cause a reduction in the markers of airway inflammation, decrease the intensity of airway hyperresponsiveness, and improve clinical symptoms of asthma. Among the available choices is nedocromil sodium, which is favored in the treatment of asthmatic children due to its very mild side-effects. It has been previously shown to improve the clinical parameters of asthma, but there are limited data on its effect on inflammatory mediators in the serum of asthmatic children. METHODS: In this double-blind, randomized, placebo-controlled 8-week trial, 39 children, aged 9-16 years, with moderate atopic asthma were randomly allocated to receive either nedocromil sodium, two puffs twice daily, 0.002 g/puff, or placebo, two puffs twice daily. The primary end points were the clinical parameters of asthma measured by asthma symptom score, FEV1, and PC20H. Other end points included the serum levels of various inflammatory markers - ECP, sIL-2R, IL-4, sICAM, and IgE. RESULTS: Clinical and inflammatory parameters improved with the use of nedocromil sodium, compared with placebo. Nedocromil significantly decreased serum levels of inflammatory markers, as shown in the following table. No correlation was found between any of the measured parameters. CONCLUSION: Nedocromil sodium provided effective anti-inflammatory treatment for children with moderate atopic asthma.     

Effect of topical corticosteroids on seasonal increases in epithelial eosinophils and mast cells in allergic rhinitis: a comparison of nasal brush and biopsy methods

BACKGROUND: Nasal brushing and nasal biopsy are well-tolerated sampling techniques. Seasonal grass pollen-induced rhinitis is characterized by epithelial mast cell infiltration and seasonal increases in both epithelial and sub-mucosal eosinophils. OBJECTIVE: To compare the ability of the nasal brush and nasal biopsy techniques to detect natural seasonal increases in eosinophils and mast cells, and to assess the influence of topical corticosteroid. METHODS: Nasal brush samples and nasal biopsies were collected from 46 grass pollen-sensitive seasonal rhinitis patients before the grass pollen season and at the peak of the pollen season following 6 weeks' treatment with either fluticasone propionate aqueous nasal spray (200 microg, twice daily) or placebo nasal spray. RESULTS: Placebo patients showed seasonal increases in epithelial eosinophils both with nasal brushing (P < 0.0001) and biopsy (P < 0.001). Epithelial mast cell numbers also increased during the pollen season as detectable by brushing (P < 0.0001) and biopsy (P < 0.03). Changes in cell numbers measured by nasal brushing correlated with those observed with nasal biopsy, both for eosinophils and mast cells (P < 0.05). Sub-mucosal eosinophils but not mast cells also increased during the pollen season (P < 0.002). Nasal brushing and biopsy revealed that fluticasone treatment inhibited seasonal increases in epithelial eosinophils (P < 0.00001) and epithelial infiltration by mast cells (nasal brushing P < 0.00001 and nasal biopsy P < 0.01). Fluticasone also inhibited seasonal increases in sub-mucosal eosinophils (P < 0.001) and significantly reduced nasal symptoms (P < 0.001). CONCLUSION: Nasal brushing harvests sufficient inflammatory cells from the surface of the nasal mucosa to be used in lieu of nasal biopsies in observation of the effect of drugs on the nasal epithelium.     

Phagocytosis of apoptotic eosinophils but not neutrophils by bronchial epithelial cells

BACKGROUND: We have previously demonstrated that human bronchial epithelial cells engulf apoptotic eosinophils. OBJECTIVES: To compare and contrast the phagocytic capabilities of monocyte-derived macrophage and primary airway epithelial cells for apoptotic granulocytes. RESULTS: Here we compared phagocytosis of human apoptotic eosinophils and neutrophils by small and large airway epithelial cells (SAEC and LAEC) and monocyte-derived macrophages. Confocal microscopy of F-actin staining and scanning and transmission electron microscopy revealed phagocytic cup formation around apoptotic eosinophils by airway epithelial cells (AEC) membranes with evidence of their digestion. Resting and cytokine-stimulated AEC did not recognize and ingest apoptotic neutrophils. The latter were phagocytosed by macrophages that exhibited greater ingestion of and higher capacity for, apoptotic eosinophils over apoptotic neutrophils. Cytochalasin D completely abolished uptake of apoptotic eosinophils by SAEC, LAEC or macrophage monolayers. Ligation of epithelial cell CD44 receptors for 24 h increased phagocytosis of apoptotic eosinophils by SAEC and LAEC with a potency comparable with that of IL-1. Phagocytosis was a specific receptor-mediated process involving integrin- (alphavbeta3, alphavbeta5, CD36), phosphatidylserine receptor- and lectin-dependent mechanisms. No significant differences were observed in avarice for apoptotic eosinophils by SAEC or LAEC either resting, CD44 monoclonal antibodies- or cytokine- stimulated, or in their usage and expression of recognition receptors. CONCLUSION: These findings further suggest and define an important role for the bronchial epithelium in the selective removal of apoptotic eosinophils from the airways in asthma.     

A comparative study of the effects of two different doses of nedocromil sodium and placebo given by pressurised aerosol in exercise-induced bronchoconstriction

Fourteen adult subjects with stable asthma were treated using a double-blind crossover, randomised protocol, with either nedocromil sodium (4 mg or 2 mg) or placebo. The agents were administered from matched pressurised aerosol inhalers 30 min before exposure to an exercise regimen which, on a previous screening day, resulted in a 24–53% (mean: 33.9%) decrease in peak expiratory flow (PEF). Both doses of nedocromil sodium were significantly superior to placebo in preventing the exercise-induced decrease in PEF and were without side effects. This study confirms and extends the results of earlier trials with nedocromil sodium and further supports the contention that this new agent may be of benefit in the treatment of reversible obstructive airways disease in the adult patient.     

Influenza virus A stimulates expression of eotaxin by nasal epithelial cells

BACKGROUND: Respiratory virus is one of the most common causes of airway inflammation, but its pathogenic mechanisms are not well understood. Eotaxin is a potent eosinophil chemoattractant and is a selective agonist for C-C chemokine receptor 3 (CCR3). Although it has recently been demonstrated that epithelial cells express eotaxin, both in vivo and in vitro, there are few data concerning the expression in viral infection. OBJECTS: We hypothesized that eotaxin may play an important role in attracting inflammatory cells into the airway after viral infection and analysed whether viral infection induces eotaxin in nasal epithelial cells in vitro. METHODS: Nasal epithelial cells obtained from polypectomy for nasal polyp were infected with influenza virus A (subtype H3N2). The cells and supernatants were collected 8, 24 and 48 h after infection. Eotaxin mRNA was analysed by RT-PCR. Eotaxin concentration in the supernatants was analysed by enzyme-linked immunosorbent assay. We also examined a blocking assay to analyse the intervention of pro-inflammatory cytokines, TNF-alpha and IL-1beta in eotaxin production induced by influenza virus. RESULTS: The results showed that eotaxin was expressed constitutively in uninfected cells, but was up-regulated for both mRNA and protein levels in infected cells. Blocking experiments using anti-TNF-alpha and anti-IL-1beta antibodies showed no effects of these agents on the level of eotaxin. In addition, UV-inactivated virus did not enhance the expression of eotaxin. CONCLUSIONS: These results suggest that influenza virus A infection in nasal epithelial cells stimulates the expression of eotaxin, and may play an important role in the pathogenesis of airway inflammation by inducing eotaxin.     

Modulation of HLA-DR antigen and ICAM-1 molecule expression on airway epithelial cells by sodium nedocromil.

OBJECTIVE: To test in vitro and in vivo the hypothesis that sodium nedocromil could modulate the expression of surface molecules on airway epithelial cells. METHODS: Human bronchial epithelial cells, obtained from surgically resected bronchi, were cultured and stimulated with recombinant IFN-gamma in the presence of sodium nedocromil. The intensity of the expression of surface molecules HLA-DR and ICAM-1 molecules on bronchial epithelial cells in vitro, was quantified by specific antibody staining and flow-cytometry analysis. Furthermore, we studied the effect of the drug on airway inflammation in vivo and on allergic rhinitis patients sensitized to house dust mites. Nasal epithelial cells were collected by brushing, at baseline and 2 to 3 weeks after treatment with sodium nedocromil. The expression of HLA-DR and ICAM-1 molecules was measured by flow-cytometry, and the proportions of neutrophils and eosinophils "contaminating" the epithelial cells evaluated by light microscopy examination of nasal brushings. RESULTS: The enhanced HLA-DR and ICAM-1 expression, induced by IFN-gamma, was effectively downregulated, in a dose-dependent manner, by sodium nedocromil. At all the concentrations tested (10(-9) to 10(-4) M), the inhibitory activity of the drug was stronger on HLA-DR than on ICAM-1 expression (P<.05, all comparisons). As compared with healthy subjects, patients with allergic rhinitis had a higher expression of HLA-DR (P<.05) but not of ICAM-1 molecules (P>.05) on nasal epithelial cells, and higher proportions of nasal eosinophils (P<.05). Treatment with sodium nedocromil downregulated the expression of HLA-DR (P<.05), but not of ICAM-1 (P>.05), and induced a mild, but not statistically significant, decrease of nasal eosinophilia (P>.05). CONCLUSION: These data demonstrate that the antiinflammatory activity of sodium nedocromil may include modulation of surface molecule expression on airway epithelial cells.     

Effects of the cyclin‐dependent kinase inhibitor R‐roscovitine on eosinophil survival and clearance

Background Eosinophils are pro‐inflammatory cells implicated in the pathogenesis of asthma and atopy. Apoptosis has been proposed as a potential mechanism underlying the resolution of eosinophilic inflammation and studies have indicated the ability of interventions that induce human eosinophil apoptosis to promote the resolution of eosinophilic inflammation. Recently, the cyclin‐dependent kinase (CDK) inhibitor R‐roscovitine was shown to enhance neutrophil apoptosis and promote the resolution of neutrophilic inflammation. Objective The purpose of this study was to examine the expression of CDKs in human blood eosinophils, the effects of R‐roscovitine on eosinophil survival in vitro and whether R‐roscovitine could influence eosinophilic lung inflammation in vivo. Methods Eosinophils were isolated from human peripheral blood and the effects of R‐roscovitine on apoptosis, degranulation and phagocytic uptake examined in vitro. The effects of R‐roscovitine on eosinophilic lung inflammation in vivo were also assessed using an ovalbumin mouse model. Results Our data demonstrate that human eosinophils express five known targets for R‐roscovitine: CDK1, ‐2, ‐5, ‐7 and ‐9. R‐roscovitine induced eosinophil apoptosis in a time‐ and concentration‐dependent manner but also accelerated transition to secondary necrosis as assessed by microscopy, flow cytometry and caspase activation. In addition, we show that R‐roscovitine can override the anti‐apoptotic signals of GM‐CSF and IL‐5. We report that the pro‐apoptotic effect of R‐roscovitine is associated with suppression of Mcl‐1L expression and that this compound enhanced phagocytic clearance of eosinophils by macrophages. Finally, we show that R‐roscovitine induces apoptosis in murine peripheral blood and spleen‐derived eosinophils; despite this, R‐roscovitine did not modulate the tissue and lumen eosinophilia characteristic of the ovalbumin mouse model of airway eosinophilia. Conclusion and Clinical Relevance These data demonstrate that R‐roscovitine is capable of inducing rapid apoptosis and secondary necrosis in eosinophils but does not affect the onset or improve the resolution of eosinophilic airway inflammation in vivo. Cite this as: N. Farahi, L. Uller, J. K. Juss, A. J. Langton, A. S. Cowburn, A. Gibson, M. R. Foster, S. N. Farrow, P. Marco‐ Casanova, A. Sobolewski, A. M. Condliffe and E. R. Chilvers, Clinical & Experimental Allergy, 2011 (41) 673–687.     

NOD-like receptors mediated activation of eosinophils interacting with bronchial epithelial cells: a link between innate immunity and allergic asthma

Key intracytosolic pattern recognition receptors of innate immunity against bacterial infections are nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs). We elucidated the NOD1 and NOD2-mediated activation of human eosinophils, the principal effector cells for allergic inflammation, upon interacting with human bronchial epithelial BEAS-2B cells in allergic asthma. Eosinophils constitutively expressed NOD1,2 but exhibited nonsignificant responses to release chemokines upon the stimulation by NOD1 ligand γ-D-glutamyl-meso-diaminopimelic acid (iE-DAP) and NOD2 ligand muramyl dipeptide (MDP). However, iE-DAP and MDP could significantly upregulate cell surface expression of CD18 and intercellular adhesion molecule (ICAM)-1 on eosinophils and ICAM-1 on BEAS-2B cells, as well as induce chemokines CCL2 and CXCL8 release in the coculture system (all P<0.05). Both eosinophils and BEAS-2B cells were the main source for CXCL8 and CCL2 release in the coculture system upon iE-DAP or MDP stimulation. Direct interaction between eosinophils and BEAS-2B cells is responsible for CCL2 release, and soluble mediators are implicated in CXCL8 release. ERK and NF-κB play regulatory roles for the expression of adhesion molecules and chemokines in coculture. Treatment with NOD1,2 ligand could induce the subepithelial fibrosis and significantly enhance the serum concentration of total IgE, chemokine CCL5 for eosinophils and T helper type 2 (Th2) cells and asthma Th2 cytokine IL-13 in bronchoalveolar lavage fluid of ovalbumin-sensitized allergic asthmatic mice (all P<0.05). This study provides further evidence of bacterial infection-mediated activation of NOD1,2 in triggering allergic asthma via the activation of eosinophils interacting with bronchial epithelial cells at inflammatory airway.     

Effects of granulocyte-macrophage colony-stimulating factor produced by intestinal epithelial cells on functional activity of hemopoietic stem cells

The population of epithelial cells in the small intestine includes precursor cells of hemopoiesis possessing the ability to form splenic colonies on day 8. Intestinal epithelial cells stimulates proliferative and colony-forming activity of hemopoietic stem cells by producing granulocyte-macrophage colony-stimulating factor.     

黄芪甲苷孵育脂肪源性干细胞对顺铂诱导肾小管上皮细胞凋亡的影响

背景：干细胞移植用于治疗急性肾损伤的有效性已经被多个研究证实,但其对肾小管上皮细胞损伤的修复机制尚不明确。 目的：观察黄芪甲苷孵育后的脂肪源性干细胞对顺铂诱导的肾小管上皮细胞凋亡的保护作用及机制。 方法：实验分为4组。2.5 μmol/L顺铂诱导肾小管上皮细胞 24 h,建立肾小管细胞损伤模型(顺铂损伤组);将脂肪源性干细胞与损伤肾小管上皮细胞共培养(脂肪源性干细胞+损伤肾小管上皮细胞组);利用Transwell小室将20 mg/L黄芪甲苷孵育脂肪源性干细胞48 h后与损伤肾小管上皮细胞共培养(黄芪甲苷孵育脂肪源性干细胞+损伤肾小管上皮细胞组);以正常肾小管上皮细胞做对照(正常对照组)。 结果与结论：与肾小管上皮细胞损伤组相比,AV/PI和TUNEL结果均显示脂肪源性干细胞+肾小管上皮细胞组和20 mg/L 黄芪甲苷脂肪源性干细胞+肾小管上皮细胞组肾小管上皮细胞发生凋亡的比例和数量明显减少;ELISA结果表明20 mg/L黄芪甲苷脂肪源性干细胞+肾小管上皮细胞组胰岛素样生长因子1分泌显著提高(P < 0.05);Western blot进一步显示20 mg/L 黄芪甲苷脂肪源性干细胞+肾小管上皮细胞组caspase-3蛋白水平明显下降,而Bcl-2的表达量明显增加(P < 0.05)。表明黄芪甲苷孵育的人脂肪源性干细胞对顺铂诱导的肾小管上皮细胞凋亡具有抑制作用,从而有利于肾小管损伤的早期恢复,其保护机制可能与增加胰岛素样生长因子1分泌,抑制caspase-3表达、上调Bcl-2水平有关。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：     

Elafin重组气道上皮细胞对铜绿假单胞菌生物被膜的抗菌作用

目的探讨Elafin重组气道上皮细胞对铜绿假单胞菌(Pseudomonas aeruginosa,Pa)生物被膜(biofilm,BF)的抗菌作用。方法体外平板法制备Pa生物被膜模型,用银染法及扫描电镜鉴定。体外培养A549细胞,将pEGEP-N1-Elafin重组到A549细胞,倒置荧光显微镜观察转染情况。采用猪胰弹性蛋白酶(NE组)、铜绿假单胞菌(Pa组)上清、大肠埃希杆菌(E．coli组)上清分别诱导孵育重组细胞24 h,另设转染未含Elafin基因空载体的A549细胞作为对照组。将成熟BF载体放入4组中继续孵育8 h,扫描电镜观察4组BF结构的变化,并于第8小时用四甲基偶氮唑盐(MTT)法测定细菌存活数。结果扫描电镜下观察到3个诱导组的BF结构较对照组的BF明显松散,尤以Pa组和NE组为甚;NE组[(3．238±0．316)×106 CFU／cm2]、Pa组细菌数量[(3．317±0．247)×106 CFU／cm2]均较对照组[(5．946±0,453)×106 CFU／cm2]显著减少(P<0．01),E．coli组细菌数量[(5．138±0．391)×106 CFU／cm2]较Pa组和NE组减少,差异均有统计学意义(P<0．01)。3个诱导组BF细菌清除率与对照组相比分别为45．6％、44．2％和13．6％。结论Elafin重组气道上皮细胞能有效清除Pa生物被膜中的细菌,而Pa产物也是Elafin表达的有效诱导物。     

Protective effect of nedocromil sodium on the interleukin-1-induced production of interleukin-8 in human bronchial epithelial cells.

Cellular constituents of the bronchial mucosa may participate in the recruitment of polymorphonuclear leukocytes to the inflamed airways through the generation of the neutrophil chemotactic peptide, interleukin-8 (IL-8). One important aspect of this interaction could be represented by the ability of pulmonary monokines, particularly IL-1, to induce gene expression of IL-8 in bronchial epithelial cells. In this study, we have evaluated the constitutive and IL-1-induced production of IL-8 by cultured human bronchial epithelial cells and examined the ability of the anti-inflammatory drug, nedocromil sodium, to inhibit the cytokine synthesis and release. Northern blot analysis demonstrated that IL-1 beta-treated human bronchial epithelial cells expressed appreciable levels of IL-8 mRNA during a period of 8 hours. This finding was associated with an increased release of immunoreactive IL-8 to the culture media, as assessed by specific ELISA. The bronchial epithelial cell-derived IL-8 demonstrated specific biologic activity, since the supernatants of stimulated bronchial epithelial cells possessed neutrophil chemotactic activity that could be inhibited by an antibody against human IL-8. Nedocromil sodium reduced the IL-1-induced release of IL-8 in a dose-dependent manner, but concentrations of the compounds, up to 10(-5) mol/L, did not affect the constitutive production of this cytokine.