Increase In Total Cell Count Research Articles

Galangin Abrogates Ovalbumin-Induced Airway Inflammation via Negative Regulation of NF-κB

Persistent activation of nuclear factor κB (NF-κB) has been associated with the development of asthma. Galangin, the active pharmacological ingredient from Alpinia galanga, is reported to have a variety of anti-inflammatory properties in vitro via negative regulation of NF-κB. This study aimed to investigate whether galangin can abrogate ovalbumin- (OVA-) induced airway inflammation by negative regulation of NF-κB. BALB/c mice sensitized and challenged with OVA developed airway hyperresponsiveness (AHR) and inflammation. Galangin dose dependently inhibited OVA-induced increases in total cell counts, eosinophil counts, and interleukin-(IL-) 4, IL-5, and IL-13 levels in bronchoalveolar lavage fluid, and reduced serum level of OVA-specific IgE. Galangin also attenuated AHR, reduced eosinophil infiltration and goblet cell hyperplasia, and reduced expression of inducible nitric oxide synthase and vascular cell adhesion protein-1 (VCAM-1) levels in lung tissue. Additionally, galangin blocked inhibitor of κB degradation, phosphorylation of the p65 subunit of NF-κB, and p65 nuclear translocation from lung tissues of OVA-sensitized mice. Similarly, in normal human airway smooth muscle cells, galangin blocked tumor necrosis factor-α induced p65 nuclear translocation and expression of monocyte chemoattractant protein-1, eotaxin, CXCL10, and VCAM-1. These results suggest that galangin can attenuate ovalbumin-induced airway inflammation by inhibiting the NF-κB pathway.

Aerosolized delivery of oxime MMB-4 in combination with atropine sulfate protects against soman exposure in guinea pigs

We evaluated the efficacy of aerosolized acetylcholinesterase (AChE) reactivator oxime MMB-4 in combination with the anticholinergic atropine sulfate for protection against respiratory toxicity and lung injury following microinstillation inhalation exposure to nerve agent soman (GD) in guinea pigs. Anesthetized animals were exposed to GD (841 mg/m3, 1.2 LCt50) and treated with endotracheally aerosolized MMB-4 (50 µmol/kg) plus atropine sulfate (0.25 mg/kg) at 30 sec post-exposure. Treatment with MMB-4 plus atropine increased survival to 100% compared to 38% in animals exposed to GD. Decreases in the pulse rate and blood O2 saturation following exposure to GD returned to normal levels in the treatment group. The body-weight loss and lung edema was significantly reduced in the treatment group. Similarly, bronchoalveolar cell death was significantly reduced in the treatment group while GD-induced increase in total cell count was decreased consistently but was not significant. GD-induced increase in bronchoalveolar protein was diminished after treatment with MMB-4 plus atropine. Bronchoalveolar lavage AChE and BChE activity were significantly increased in animals treated with MMB-4 plus atropine at 24 h. Lung and diaphragm tissue also showed a significant increase in AChE activity in the treatment group. Treatment with MMB-4 plus atropine sulfate normalized various respiratory dynamics parameters including respiratory frequency, tidal volume, peak inspiratory and expiratory flow, time of inspiration and expiration, enhanced pause and pause post-exposure to GD. Collectively, these results suggest that aerosolization of MMB-4 plus atropine increased survival, decreased respiratory toxicity and lung injury following GD inhalation exposure.

Angiotensin‐(1–7) inhibits allergic inflammation, via the MAS1 receptor, through suppression of ERK1/2‐ and NF‐κB‐dependent pathways

BACKGROUND AND PURPOSE Angiotensin-(1-7) [Ang-(1-7)] has anti-inflammatory effects in models of cardiovascular disease and arthritis, but its effects in asthma are unknown. We investigated whether Ang-(1-7) has anti-inflammatory actions in a murine model of asthma. EXPERIMENTAL APPROACH The effects of Ang-(1-7) alone or in combination with the MAS1 receptor antagonist, A779, were evaluated over a 4 day period in an ovalbumin-challenged mouse model of allergic asthma. On day 5, bronchoalveolar lavage was performed, and lungs were sectioned and assessed histologically for quantification of goblet cells, perivascular and peribronchial inflammation and fibrosis. Biochemical analysis of the pro-inflammatory ERK1/2 and IκB-α was assessed. In addition, the effect of Ang-(1-7) on proliferation of human peripheral blood mononuclear cells (HPBMC) was investigated. KEY RESULTS Ang-(1-7) attenuated ovalbumin-induced increases in total cell counts, eosinophils, lymphocytes and neutrophils. Ang-(1-7) also decreased the ovalbumin-induced perivascular and peribronchial inflammation, fibrosis and goblet cell hyper/metaplasia. Additionally, Ang-(1-7) reduced the ovalbumin-induced increase in the phosphorylation of ERK1/2 and IκB-α. These effects of Ang-(1-7) were reversed by the MAS1 receptor antagonist A779. Furthermore, Ang-(1-7) inhibited phytohaemagglutinin (PHA)-induced HPBMC proliferation. CONCLUSION AND IMPLICATIONS Ang-(1-7), via its MAS1 receptor, acts as an anti-inflammatory pathway in allergic asthma, implying that activation of the MAS1 receptor may represent a novel approach to asthma therapy.

The bradykinin B1 receptor antagonist R-954 inhibits Ehrlich tumor growth in rodents

The present study investigated the effects of a new bradykinin B1 receptor antagonist, R-954, on the development of Ehrlich ascitic tumor (EAT) induced by the intraperitoneal inoculation of EAT cells in mice and the formation of a solid tumor by the subcutaneous injection of the cells in rat paw. The development of the tumor was associated with an increase in mouse total cell counts in bone marrow (10.8-fold), ascitic fluid (14.6-fold), and blood (12.6-fold). R-954 (2mg/kg, s.c.) significantly reduced the ascitic fluid volume (63.7%) and the mouse weight gain (30.5%) after 10 consecutive days of treatment. The B1 antagonist as well as the anti-neoplasic drug vincristine also significantly inhibited the increase in total cell count in bone marrow, ascitic fluid, and blood. R-954 reduced significantly the total protein extravasation (57.3%), the production of nitric oxide (56%), PGE2 production (82%), and TNFα release (85.7%) in mice peritoneal cavity whereas vincristine reduced the release of these inflammatory mediators by 84–94%. The increase in paw edema after intraplantar injection of EAT cells was reduced by approximately 52% by either R-954 or vincristine treatment. In conclusion, this study presents for the first time the antitumoral activity of a new bradykinin B1 receptor antagonist on ascitic and solid tumors induced by Ehrlich cell inoculation in mice and rats.

M 3 muscarinic receptor antagonist bencycloquidium bromide attenuates allergic airway inflammation, hyperresponsiveness and remodeling in mice

M 3 muscarinic receptors are localized on inflammatory cells, airway smooth muscle, and submucosal glands, known to mediate bronchoconstriction, mucus secretion, and airway remodeling. It is hypothesized bencycloquidium bromide (BCQB), a novel M 3 receptor antagonist, might have potential effects on airway hyperresponsiveness, inflammation and airway remodeling in a murine model of asthma. Mice sensitized and challenged with ovalbumin developed airway inflammation. Bronchoalveolar lavage fluid was examined to determine the total and differential cell counts, and cytokine levels. Lung tissues were evaluated for cell infiltration, mucus hypersecretion, airway remodeling, and the expression of inflammatory biomarkers. Airway hyperresponsiveness was monitored by direct airway resistance analysis. Inhalation administration of BCQB significantly not only reduced ovalbumin-induced airway hyperresponsiveness comparing to methacholine, and prevented the ovalbumin-induced increase in total cell counts and eosinophil counts. Reverse transcriptase polymerase chain reaction analysis of whole lung lysates revealed that BCQB markedly suppressed ovalbumin-induced mRNA expression of eotaxin, IL-5, IL-4 and MMP-9, and increased mRNA expression of IFN-γ and TIMP-1 in a dose-dependent manner. Substantial IFN-γ/IL-4 (Th1/Th2) levels were recovered in bronchoalveolar lavage fluid after BCQB treatment. In addition, histological studies showed that BCQB dramatically inhibited ovalbumin-induced lung tissue eosinophil infiltration, airway mucus production and collagen deposition in lung tissues. Results reported in current paper suggest that M 3 receptors antagonist may provide a novel therapeutic approach to treat airway inflammation, hyperresponsiveness and remodeling.

A further investigation concerning correlation between anti-fibrotic effect of liposomal quercetin and inflammatory cytokines in pulmonary fibrosis

It is widely accepted that inflammatory cells and cytokines play vital roles in the process of pulmonary fibrosis. The aim of this study was to evaluate the preventative effects of liposomal quercetin against bleomycin-induced pulmonary fibrosis in vivo. The underlying molecular mechanisms were also investigated. Bleomycin was injected intratracheally at a single dose of 5 U/kg for pulmonary fibrosis induction. Liposomal quercetin was intravenously injected 1 day prior to bleomycin administration and continued to the end of the study (for 4 weeks). Our results showed that liposomal quercetin diminished the increase of total cell counts and macrophage counts in bronchoalveolar lavage fluid. The neutrophil and lymphocyte counts were also significantly decreased both on day 7 and 14 after liposomal quercetin injection ( P < 0.05). The levels of TNF-α, IL-1β, and IL-6 in bronchoalveolar lavage fluid at day 7 were strikingly reduced in liposomal quercetin treated group compared with bleomycin-induced group (TNF-α: 56.21 ± 3.16 pg/ml vs.79.85 ± 6.91 pg/ml; IL-1β: 37.64 ± 2.10 pg/ml vs. 73.29 ± 5.78 pg/ml; IL-6: 88.52 ± 5.96 pg/ml vs. 128.56 ± 8.72 pg/ml; P < 0.05). Moreover, the treatment with liposomal quercetin exerted approximately 35.8% reduction of the hydroxyproline content in contrast to the bleomycin-induced group ( P < 0.05). Histopathological assessment revealed that treatment with liposomal quercetin apparently lessened the lung fibrosis areas and collagen deposition accompanied with decreased expression of TGF-β1. Thus, our results suggested that liposomal quercetin could attenuate the bleomycin-induced pulmonary fibrosis in vivo by the suppression of inflammatory cytokines.

Cell population and elastase activity in bronchoalveolar lavage fluid from rats exposed to high concentration of nitrogen dioxide

The purpose of this study was to clarify what elastase acts primarily to injure the lung tissue when animals are exposed to nitrogen dioxide (NO2). Rats were exposed to 50 ppm NO2 for 5 hours a day on 7 consecutive days. Approximately six animals were sacrificed after the exposure of the 1st, 3rd, 5th and 7th days. On the 1st day, diffuse alveolar edema was seen accompanying deposits of fibrin nets, suggesting the increase of permeability. Inflammatory cell infiltration was seen in terminal bronchioles and alveolar ducts on the 3rd day, however these changes diminished gradually thereafter. The increase of total cell count was seen in bronchoalveolar lavage fluid on day 3 and thereafter. The number of neutrophils was raised markedly on the 3rd day, whereas that of macrophages showed a gradual increase thereafter. The protein concentration of bronchoalveolar lavage fluid increased markedly on the 1st day and was reduced rapidly thereafter. Elastase activity was measured in bronchoalveolar lavage fluid using succinyl-trialanyl-p-nitroanilide as substrate. Total elastase activity was significantly increased on the 1st and 3rd day. Inhibition studies using EDTA and DFP suggested that most of the elastase activity was due to a metaleoprotease. These data suggest that elastase from macrophage may be mainly related to nitrogen dioxide-induced lung injury.

Down-regulation of Caveolin-1, an Inhibitor of Transforming Growth Factor-β Signaling, in Acute Allergen-induced Airway Remodeling

Asthma can progress to subepithelial airway fibrosis, mediated in large part by transforming growth factor-beta (TGF-beta). The scaffolding protein caveolin-1 (cav1) can inhibit the activity of TGF-beta, perhaps by forming membrane invaginations that enfold TGF-beta receptors. The study goals were 1) to evaluate how allergen challenge affects lung expression of cav1 and the density of caveolae in vivo 2) to determine whether reduced cav1 expression is mediated by interleukin (IL)-4 and 3) to measure the effects of decreased expression of cav1 on TGF-beta signaling. C57BL/6J, IL-4-deficient mice, and cav1-deficient mice, sensitized by intraperitoneal injections of phosphate-buffered saline or ovalbumin (OVA) at days 0 and 12, received intranasal phosphate-buffered saline or OVA challenges at days 24, 26, and 28. Additionally, another group of C57BL/6J mice received IL-4 by intratracheal instillation for 7 days. We confirmed that the OVA-allergen challenge increased eosinophilia and T-helper type 2-related cytokine levels (IL-4, IL-5, and IL-13) in bronchoalveolar lavage. Allergen challenge reduced lung cav1 mRNA abundance by 40%, cav1 protein by 30%, and the number of lung fibroblast caveolae by 50%. Administration of IL-4 in vivo also substantially decreased cav1 expression. In contrast, the allergen challenge did not decrease cav1 expression in IL-4-deficient mice. The reduced expression of cav1 was associated with activation of TGF-beta signaling that was further enhanced in OVA-sensitized and challenged cav1-deficient mice. This study demonstrates a previously unknown modulation of TGF-beta signaling by IL-4, via cav1, suggesting novel therapeutic targets for controlling the effects of TGF-beta and thereby ameliorating pathological airway remodeling.

Glycogen Synthase Kinase-3β Inhibition Attenuates Asthma in Mice

Persistent activation of nuclear factor-kappaB has been associated with the development of asthma. Glycogen synthase kinase-3beta is known to regulate the activity of nuclear factor-kappaB. We hypothesized that inhibition of glycogen synthase kinase-3beta may have anti-inflammatory effects in allergic asthma. BALB/c mice sensitized and challenged with ovalbumin developed airway inflammation. Bronchoalveolar lavage fluid was assessed for total and differential cell counts, and for cytokine and chemokine levels. Lung tissues were examined for cell infiltration and mucus hypersecretion, and for the expression of inflammatory biomarkers. Serum immunoglobulin E levels were determined by enzyme-linked immunosorbant assay. Airway hyperresponsiveness was monitored by direct airway resistance analysis. Intravenous administration of 4-benzyl-2-methyl-1,2,4-thiadiazolidine-3,5-dione (TDZD-8), a selective glycogen synthase kinase-3beta inhibitor, significantly inhibited ovalbumin-induced increases in total cell counts, eosinophil counts, and IL-5, IL-13, and eotaxin levels recovered in bronchoalveolar lavage fluid in a dose-dependent manner. TDZD-8 substantially reduced the serum levels of ovalbumin-specific IgE. Histologic studies showed that TDZD-8 dramatically inhibited ovalbumin-induced lung tissue eosinophilia and airway mucus production. TDZD-8 also markedly suppressed ovalbumin-induced mRNA expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, Muc5ac, and three members of the chitinase family (acidic mammalian chitinase, Ym1, and Ym2). In addition, TDZD-8 significantly reduced ovalbumin-induced airway hyperresponsiveness to inhaled methacholine. Western blot analysis of whole lung lysates revealed that TDZD-8 markedly attenuated the phosphorylation of the nuclear factor-kappaB subunit p65 from ovalbumin-challenged mice. Our findings suggest that inhibition of glycogen synthase kinase-3beta may provide a novel means for the treatment of allergic airway inflammation.

Lower Airway Inflammation Assessed by Induced Sputum in a Cluster of Cases Suggestive of Organic Dust Toxic Syndrome

in a Cluster of Cases Suggestive of Organic Dust Toxic Syndrome R. Castano, J. L. Malo, C. Lemiere, M. Labrecque, A. Cartier; Hopital du Sacre-Coeur de Montreal, Montreal, PQ, CANADA. RATIONALE: To examine pulmonary responses and characterize airway inflammation in workers with respiratory symptoms suggestive of Organic Dust Toxic Syndrome (ODTS). METHODS: We assessed 14 workers of a large factory of sanitary napkins complaining of recurrent work-related cough, shortness of breath, phlegm production and fever with chills. All workers underwent specific inhalation challenges (SIC) for 2 to 4 hours with dust obtained from the floor next to the operating machines. All subjects had measurements of temperature, expiratory flows, white blood cell count (WBC), carbon monoxide diffusing capacity (DLCO) and induced sputum before and after exposure. RESULTS: Only one subject presented symptoms on exposure suggesting extrinsic allergic alveolitis (EAA) with increases in temperature (36.3 to 37.88C) and WBC (5.2 to 10.7 cells per cc) and a decrease in DLCO (23.3 to 18.4). After exposure only one subject had a significant decrease (26%) in forced expiratory volume in one second. In induced sputum 13 subjects had an increase in total cell counts (mean 55.3 10 c/ml; range 8.2-113.4) and 12 in neutrophils (mean 39%; range 20-92%). CONCLUSIONS: We have thus described workers with features of ODTS, EAA and asthma. We hypothesize that these conditions may be considered one syndrome with a wide spectrum of severity ranging from a less severe condition (ODTS) in one end of the spectrum to a more severe disease in the other (EAA). Results also support the use of induced sputum in the investigation of ODTS. The etiology of this syndrome in our workers is still unknown. Funding: Universite de Montreal

Role of Toll-like receptor 4 for the pathogenesis of acute lung injury in Gram-negative sepsis

Proinflammatory cytokines as well as nitric oxide (NO) play a major role in mediating the response to lipopolysaccharide (LPS). The present study tested the hypothesis that LPS induces proinflammatory cytokines in the lung via the Toll-like receptor 4 (TLR4)/CD14 signalling cascade. Control mice and TLR4-deficient (TLR4-D) mice were used to test TLR4-mediated effects of LPS. Both strains received either Escherichia coli LPS (20 mg kg-1 intraperitoneal) or saline and their lungs were collected at different time points. Pulmonary nuclear factor kappaB (NFkappaB) activation was investigated with electromobility shift assay. mRNA expression of inflammatory mediators and their corresponding receptors were detected with Ribonuclease Protection Assay. Protein expression was detected by ELISA and western blotting. Inducible NO synthase (iNOS) expression was monitored by RT-PCR and iNOS activity by conversion of l-arginine to citrulline. Immune cells were sampled by bronchoalveolar lavage (BAL) and classified. LPS application induced CD14-, but not TLR4 protein expression in control mice. Activation of pulmonary NFkappaB was observed within 60 min in control, but not in TLR4-D mice. Six hours of LPS administration induced a significant increase in pulmonary tumour necrosis factor alpha-, interleukin-1beta- and interleukin-6 mRNA and protein expression in control mice compared to TLR4-D mice. Furthermore, LPS induced a significantly higher increase of the iNOS expression and catalytic activity in control mice than in TLR4-D mice. BAL revealed an increase in total cell count in all LPS treated mice. Our findings suggest that TLR4 plays a key role for regulating the expression of relevant cytokines within the lung during endotoxic shock.

The Effect of Aerosolized and Intravenously Administered Clenbuterol and Aerosolized Fluticasone Propionate on Horses Challenged with Aspergillus fumigatus Antigen

Beta-agonists have been shown to display anti-inflammatory properties in several experimental models. The aim of this study was to investigate the anti-inflammatory properties of clenbuterol (CB), administered either intravenously or by aerosol, in comparison with fluticasone propionate (FP) in recurrent airway obstruction (RAO)-susceptible horses. Eight horses, of which five were known to be susceptible to RAO, underwent an inhalation challenge with Aspergillus fumigatus (AF) antigen and were treated with CB intravenously, CB by aerosol, or FP by aerosol. Twenty-four hours after the challenge, bronchoalveolar lavage was performed, the total and differential cell counts were assessed, and cytokines were measured in isolated alveolar macrophages. After challenge with AF, RAO-susceptible horses showed an increase in total cell count, based on an increase in macrophages and lymphocytes, which was inhibited by treatment with intravenous CB, aerosolized CB and aerosolized FP. Neutrophil ratios were decreased when treated with aerosolized CB and FP. Expression of interleukin (IL)-1beta and IL -8 was significantly increased after AF challenge . Interleukin -1beta was significantly decreased following treatment with intravenous CB, aerosolized CB and aerosolized FP, whereas only FP decreased the expression of IL-8. These data suggest that the anti-inflammatory property of CB provide new opportunities in the therapeutic intervention of early inflammation in RAO.

Anti-inflammatory effect of amurensin H on asthma-like reaction induced by allergen in sensitized mice1

To explore the anti-inflammatory effects of amurensin H on asthma-like reaction induced by allergen in sensitized mice. BALB/c mice were sensitized by ovalbumin (OVA, ip) on d 0 and d 14 and challenged with 1% OVA on d 18 to 22. Mice developed airway eosinophilia, mucus hypersecretion, and elevation in cytokine levels. Mice were administered amurensin H orally at the doses of 49, 70, or 100 mg/kg once every day from d 15 to the last day. Bronchoalveolar lavage fluid (BALF) were collected at 24 h and 48 h after the last OVA challenge. Levels of tumor necrosis factor-alpha (TNF-alpha), interleukin 4 (IL-4), interleukin 5 (IL-5), and interleukin 13 (IL-13) in BALF were measured using ELISA method. Differential cell counts of macrophages, lymphocytes, neutrophils and eosinophils were performed in 200 cells per slide (one slide per animal). Lung tissue sections of 6-mum thickness were stained with Mayer's hematoxylin and eosin for assessment of cell infiltration, mucus production, and tissue damage. Oral administration of amurensin H significantly inhibited OVA-induced increases in total cell counts, eosinophil counts, and TNF- alpha, IL-4, IL-5 and IL-13 levels in BALF. In addition, amuresin H dramatically decreased OVA-induced lung tissue damage and mucus production. Amurensin H may have therapeutic potential for the treatment of allergic airway inflammation.

Hypersensitivity Pneumonitis Induced by Spores of Penicillium citrinum in a Worker Cultivating Enoki Mushroom

A 47-year-old Japanese woman was admitted to our hospital with a 2-week history of dry cough and shortness of breath. She had been engaged in Enoki mushroom production for 22 years. Chest X-ray and chest computed tomography (CT) scan showed bilateral fine-nodular shadows and ground glass opacity. Bronchoalveolar lavage fluid demonstrated an increase of total cell counts with predominant lymphocytosis. Pathological specimens obtained by video-assisted thoracoscopic surgery revealed alveolitis and noncaseating granuloma with giant cells. Lymphocyte stimulation test showed positive responses with Enoki mushroom, culture medium, and Penicillium citrinum. On double immunodiffusion test, a precipitation line was observed between patient's serum and Penicillium citrinum antigen. She was found to have hypersensitivity pneumonitis caused by Penicillium citrinum. This is the first report of mushroom worker's lung caused by Penicillium citrinum.

Influence of pH Control Agents on Entomotoxicity Potency of Bacillus thuringiensis using Different Raw Materials

In this investigation, ammonium hydroxide and acetic acid were used as pH control agents during Bacillus thuringiensis (Bt) fermentation in a pilot scale fermentor (150-l) employing two secondary wastewater sludges from two different wastewater treatment plants (CUQS and JQS) and semi-synthetic soybean meal medium as raw materials. Regardless of the cultivation medium, a substantial increase in total cell count, spore count, protease activity and entomotoxicity was achieved when the pH of the culture was controlled using NH4OH/CH3COOH. At harvest, total cell count increased by almost 17%, 33% and 25%; protease activity was enhanced by 12%, 33% and 53% and maximal spore count augmented by almost 28%, 48% and 33% in CUQS, JQS and soybean medium, respectively. Entomotoxicity potency was improved by 22%, 21% and 14% in CUQS, JQS and soybean medium, respectively compared to results obtained with NaOH/H2SO4 as pH control agents. A higher entomotoxicity was also observed using sludge compared to the soybean medium. This improvement of the Bt process performance was a consequence of the addition of rapidly utilizable carbon and nitrogen source through pH control, which stimulated endotoxin production in the crystal and enhanced sporulation.

An anti-inflammatory role for a phosphoinositide 3-kinase inhibitor LY294002 in a mouse asthma model

Phosphoinositide 3-kinase (PI3K) exhibits broad functional effects in immune cells. We investigated the role of PI3K in allergic airway inflammation using LY294002, a specific PI3K inhibitor, in a mouse asthma model. BALB/c mice were sensitized and challenged with ovalbumin (OVA), and developed airway eosinophilia, mucus hypersecretion, elevation in cytokine levels, and airway hyperresponsiveness. Intratracheal administration of LY294002 significantly inhibited OVA-induced increases in total cell counts, eosinophil counts, and IL-5, IL-13, and eotaxin levels in bronchoalveolar lavage fluid. Histological studies show that LY294002 dramatically inhibited OVA-induced lung tissue eosinophilia and airway mucus production. In addition, LY294002 significantly suppressed OVA-induced airway hyperresponsiveness to inhaled methacholine. Western blot analysis of whole lung lysates shows that LY294002 markedly attenuated OVA-induced serine phosphorylation of Akt, a direct downstream substrate of PI3K. Taken together, our findings suggest that inhibition of PI3K signaling pathway can suppress T-helper type 2 (Th2) cytokine production, eosinophil infiltration, mucus production, and airway hyperresponsiveness in a mouse asthma model and may have therapeutic potential for the treatment of allergic airway inflammation.

Ex-Vivo Expansion of Multipotent CD133+ Stem Cells with VEGF, FLT3l and SCGF.

The rare CD133+ stem cell population contains both hematopoietic and endothelial progenitors. Successful ex-vivo expansion of this multipotent population would therefore be of great benefit in many clinical settings including stem cell transplantation and gene therapy. We developed a cell culture system containing the recombinant human cytokines vascular endothelial growth factor (VEGF), FLT3 ligand (FLT3L) and stem cell growth factor (SCGF) for ex-vivo expansion of purified human CD133+ stem cells obtained from leukapheresis products from patients pre-treated with G-CSF.FACS analysis, colony assays and NOD-SCID transplantation studies were performed to monitor stem cell and endothelial phenotype in-vitro and in-vivo. Cultivation with VEGF, FLT3L and SCGF induced a mean 2200-fold increase of total cell counts in 5 weeks. FACS analysis revealed persistence of 6–15% CD133+ stem cells indicating proliferation and survival of primitive hematopoietic stem cells. 5–6% of the proliferating cells expressed the endothelial markers CD144 (VE-Cadherin) and von-Willebrand factor (vWF). Ex-vivo expanded stem cells could be differentiated into adherent endothelial cells after withdrawal of SCGF and FLT3L allowing generation of large numbers of endothelial cells. Colony-assays showed an increase of hematopoietic and endothelial colonies after 5 weeks of ex-vivo expansion indicating simultaneous proliferation of hematopoietic and endothelial precursors under the established culture conditions (CFU-E 60-fold, CFU-GEMM 48-fold, CFU-GM 59-fold, CFU-G 99-fold, CFU-M 1356-fold and CFU-EC 1843-fold).To assess in-vivo functionality, hematopoietic stem cells expanded ex-vivo for 7, 14, 21 and 32 days were transplanted into sublethally irradiated NOD-SCID mice. For each expansion period, the mean percentage of anti-human CD45 positive bone marrow cells 3 months post-transplantation was 11, 3, 3 and 1%, respectively. Human CD45+ cells for each set of experiments contained a mean of 15, 26, 8 and 32% T-cells (CD3+), 9, 0, 7 and 21% B-cells (CD19+), 24, 2, 2 and 11% monocytes (CD14+), 21, 3, 1 and 12% granulocytes (CD33+) and 19, 37, 44 and 24% stem cells (CD34+) (d7 (n=5), d14 (n=4), d21 (n=7) and d32 (n=6) respectively).Our experiments showed multilineage engraftment of human stem cells expanded for more than 4 weeks ex-vivo. Therefore our culture system provides a tool to generate large numbers of human stem and endothelial cells for clinical purposes.

Successful Expansion of Umbilical Cord Blood Cells as a Source of Hematopoietic Progenitors for Adult Transplantation.

The low yield of progenitor CD34+ cells recovered from umbilical cord blood (UCB) limits the utility of this source for transplantation in adults. This limitation has triggered investigations into how ex vivo expansion of hematopoietic stem cells (HSC) could be achieved to allow for transplantation in larger recipients. In the present study, the incubation of MNC and not selected CD34+cells in the presence of SCF 25ng/ml+MGDF 10ng/ml+FLt-3 25ng/ml+IL-6 20ng/ml, and 10% human serum in stroma-free liquid culture generated long-term expansion of transplantable UCB HSC. In vitro, HSC expansion from 13 UCB lasted >7 months giving 39, 1.3x104, and 4.7 x109 fold increase in total cell count after 14, 70 and 217 d of expansion as compared to d0 (105/ml). Similarly, CD34+ and CD34+/CD38− cell populations increased reaching 229 and 2.2x105 and 91 and 2.2x104 fold after 14 and 70d of expansion. Examination of cell morphology and analysis by flow cytometry showed the presence of primitive and mature cells belonging to all hematopoietic cell lineages. Similarly, multilineage colonies with recloning capacity were generated in culture. Erythroid, myeloid and mixed colonies increased by 116 and 1.8x104 fold and megakaryocytic colonies by 8 and 527 fold after 14 and 70d. Expanded cells were karyotypically normal and lacked the most common chromosome translocations seen in AML and CML t (15,17) and t (9, 22). HSC expanded for 6 and 13 weeks and cropreserved for 6–11 months were able to re-expand in liquid culture and generate colonies capable of recloning and multi-lineage differentiation. We estimated the frequency of SCID repopulating cells (SRC) in UCB samples expanded for 2 and 12 w using 1000,500,250 and 125 unselected CD34+ cells injected intravenously into sublethally irradiated NOD/SCID mice. Mice were sacrificed 20 weeks after transplantation. Human cell engraftment measured as CD45+ (HuCD45+) was detected in all mice (x3mice/dilution) (0.1–9.8%). In addition, HuCD45+ cells with multilineage phenotype were present, (CD19 (lymphoid), CD33 (myeloid), CD71and Glycophorin-A (erythroid) as well as CD34+/CD38− cells). SRC increased by 90 fold after 2 weeks of expansion and by 187 fold after 12 weeks compared to unexpanded CD34+cells. Additional proof of human cell engraftment was documented using semisolid culture (MethoCultTM GF H4434 Stem Cell Technologies). Human myeloid and erythroid colonies were generated from all dilutions, and counts ranged between 63–271/500,000 MNC.Initial studies to test the relative magnitude of UCB HSC expansion from 24-well plates to culture bags (OptiCyte TM, Baxter) using one UCB, the total cell count increased by (6.3 and 20 (bags) Vs 2.3 and 3.3 fold (wells) after 7 and 14d) and CD34+ subpopulations including CD34+/CD38−. Based on these ongoing results, a phase II clinical trial using ex vivo expanded UCB for 14d in a setting of sub ablative Conditioning is planned.

Anti-inflammatory effects of mitogen-activated protein kinase kinase inhibitor U0126 in an asthma mouse model.

Mitogen-activated protein kinase (MAPK) signaling cascade plays a pivotal role in the activation of inflammatory cells. Recent findings revealed that the activity of p42/44 MAPK (also known as extracellular signal-regulated kinase (ERK)) in the lungs was significantly higher in asthmatic mice than in normal controls. We hypothesized that inhibition of ERK activity may have anti-inflammatory effects in allergic asthma. BALB/c mice were sensitized with OVA and, upon OVA aerosol challenge, developed airway eosinophilia, mucus hypersecretion, elevation in cytokine and chemokine levels, up-regulation of VCAM-1 expression, and airway hyperresponsiveness. Intraperitoneal administration of U0126, a specific MAPK/ERK kinase inhibitor, significantly (p < 0.05) inhibited OVA-induced increases in total cell counts, eosinophil counts, and IL-4, IL-5, IL-13, and eotaxin levels recovered in bronchoalveolar lavage fluid in a dose-dependent manner. U0126 also substantially (p < 0.05) reduced the serum levels of total IgE and OVA-specific IgE and IgG1. Histological studies show that U0126 dramatically inhibited OVA-induced lung tissue eosinophilia, airway mucus production, and expression of VCAM-1 in lung tissues. In addition, U0126 significantly (p < 0.05) suppressed OVA-induced airway hyperresponsiveness to inhaled methacholine in a dose-dependent manner. Western blot analysis of whole lung lysates shows that U0126 markedly attenuated OVA-induced tyrosine phosphorylation of ERK1/2. Taken together, our findings implicate that inhibition of ERK signaling pathway may have therapeutic potential for the treatment of allergic airway inflammation.

OxLDL stimulates cell proliferation through a general induction of cell cycle proteins

Oxidized low-density lipoprotein (oxLDL) may be involved in atherosclerosis by stimulating proliferation of cells in the vessel wall. The purpose of this study was to identify the mechanism by which oxLDL induces proliferation. Quiescent human fibroblasts and rabbit smooth muscle cells were treated with 0, 10, or 50 microg/ml oxLDL for 24-48 h. This resulted in significant increases in total cell counts at both concentrations of oxLDL, at both time points, for both types of cells. Western blot analysis revealed that oxLDL-stimulated cell proliferation was associated with significant increases in the expression of proteins that regulate entry into and progression through the cell cycle [cell division cycle 2, cyclin-dependent kinase (cdk) 2, cdk 4, cyclin B1, cyclin D1, and PCNA]. Surprisingly, the expression of cell cycle inhibitors (p21 and p27) was stimulated by oxLDL as well, but this was to a lesser extent than the effects on cell cycle-activating proteins. OxLDL also induced nuclear localization of all cell cycle proteins examined. The similar effects of oxLDL on the translocation and expression of both cell cycle-activating and -inhibiting proteins may explain the controlled proliferative phenomenon observed in atherosclerosis as opposed to the more rapid proliferative event characteristic of cancer.