594 research outputs found
Human mesenchymal stem cells reduce mortality and bacteremia in gram-negative sepsis in mice in part by enhancing the phagocytic activity of blood monocytes
No full textThe potential therapeutic value of cell-based therapy with mesenchymal stem cells (MSC) has been reported in mouse models of polymicrobial peritoneal sepsis. However, the mechanisms responsible for the beneficial effects of MSC have not been well defined. Therefore, we tested the therapeutic effect of intravenous bone marrow-derived human MSC in peritoneal sepsis induced by gram-negative bacteria. At 48 h, survival was significantly increased in mice treated with intravenous MSC compared with control mice treated with intravenous fibroblasts (3T3) or intravenous PBS. There were no significant differences in the levels of TNF-a, macrophage inflammatory protein 2, or IL-10 in the plasma. However, there was a marked reduction in the number of bacterial colony-forming units of Pseudomonas aeruginosa in the blood of MSC-treated mice compared with the 3T3 and PBS control groups. In addition, phagocytic activity was increased in blood monocytes isolated from mice treated with MSC compared with the 3T3 and PBS groups. Furthermore, levels of C5a anaphylotoxin were elevated in the blood of mice treated with MSC, a finding that was associated with upregulation of the phagocytosis receptor CD11b on monocytes. The phagocytic activity of neutrophils was not different among the groups. There was also an increase in alternately activated monocytes/macrophages (CD163- and CD206-positive) in the spleen of the MSC-treated mice compared with the two controls. Thus intravenous MSC increased survival from gram-negative peritoneal sepsis, in part by a monocyte-dependent increase in bacterial phagocytosis
Long-term clearance of liquid and protein from the lungs of unanesthetized sheep
No full text We measured the removal of 100 ml of autologous serum from the air spaces and lungs of unanesthetized, spontaneously breathing sheep at 4, 12, and 24 h. In the first 4 h, there was a rapid clearance of the liquid volume (8.3%/h), similar to our results in anesthetized ventilated sheep (Matthay et al., J. Appl. Physiol. 53: 96–104, 1982). However, liquid removal progressively slowed to 3.3 and 1.4%/h at 12 and 24 h, respectively. In contrast, protein clearance (as measured by 125I-albumin instilled with the serum) was monoexponential and slow (1%/h). The slowing of liquid clearance appears to be a function of the rising protein osmotic pressure of the residual protein in the air spaces (protein concentration doubled in 24 h). Because protein solutions are chemotactic for neutrophils, we quantified the movement of liquid from the extracellular space into the alveolar compartment with a plasma protein tracer (131I-albumin), so that our final calculation of alveolar liquid clearance would take into account bidirectional movement of liquid across the alveolar barrier. The corrected values for net liquid clearance are slightly faster (less than 10% of the instilled volume). </jats:p
The Beta Agonist Lung Injury TrIal (BALTI) : prevention trial protocol
No full textBackground: Acute lung injury complicates approximately 25-30% of subjects undergoing oesophagectomy.
Experimental studies suggest that treatment with beta agonists may prevent the development of acute lung injury by decreasing inflammatory cell infiltration, activation and inflammatory cytokine release, enhancing basal alveolar fluid clearance and improving alveolar capillary barrier function.
Methods/Design: The Beta Agonist Lung Injury TrIal (prevention) is a multi-centre, randomised, double blind,
placebo-controlled trial. The aim of the trial is to determine in patients undergoing elective transthoracic
oesphagectomy, if treatment with inhaled salmeterol 100 mcg twice daily started at induction of anaesthesia and
continued for 72 hours thereafter compared to placebo affect the incidence of early acute lung injury and other
clinical, resource and patient focused outcomes. The primary outcome will be the development of acute lung
injury within 72 hours of oesophagectomy. The trial secondary outcomes are the development of acute lung injury during the first 28 days post operatively; PaO2: FiO2 ratio; the number of ventilator and organ failure free days, 28 and 90 day survival; health related quality of life and resource utilisation. The study aims to recruit 360 patients from 10 UK centres
Inhibition of CD18 or CD11b attenuates acute lung injury after acid instillation in rabbits
No full textFolkesson, Hans G., and Michael A. Matthay. Inhibition of CD18 or CD11b attenuates acute lung injury after acid instillation in rabbits. J. Appl. Physiol. 82(6): 1743–1750, 1997.—Acid-induced lung injury is mediated primarily by activated neutrophils. Although a prior study demonstrated that acid-induced neutrophil influx into the air spaces was not CD18 dependent, we hypothesized that either a neutralizing anti-CD18 monoclonal antibody (MHM23) or a neutrophil inhibitory factor (NIF), NIF (CD11b,18), might attenuate acid-induced lung injury in rabbits by interfering with neutrophil activation. This hypothesis derived from in vitro studies that reported that anti-CD18 therapy prevented tumor necrosis factor-α-induced neutrophil activation. Hydrochloric acid (pH = 1.5 in one-third normal saline) or one-third normal saline (4 ml/kg) was instilled into the lungs of ventilated, anesthetized rabbits. The rabbits were studied for 6 h. In acid-instilled rabbits without the anti-CD18 monoclonal antibody or NIF (CD11b,18), severe lung injury developed. In acid-instilled rabbits, pretreatment (5 min before acid) with the anti-CD18 monoclonal antibody (2 mg/kg iv) or pretreatment with the NIF (anti-CD11b,18, 10 mg/kg iv) prevented 50–70% of acid-induced abnormalities in oxygenation, the increase in extravascular lung water, and extravascular protein accumulation. The anti-CD18 monoclonal antibody was associated with a significant increase in air space neutrophils by bronchoalveolar lavage, suggesting that the neutrophils respond normally to chemotactic stimuli but that the neutrophils did not injure the lung even though they accumulated in the air spaces. In summary, neutralization of CD18 attenuates the acute lung injury after acid instillation without reducing the number of neutrophils in the air spaces, suggesting that anti-CD18 therapy may be beneficial because of its capacity to reduce neutrophil activation.</jats:p
Contribution of CFTR to apical-basolateral fluid transport in cultured human alveolar epithelial type II cells
No full textPrevious studies in intact lung suggest that CFTR may play a role in cAMP-regulated fluid transport from the distal air spaces of the lung. However, the potential contribution of different epithelial cells (alveolar epithelial type I, type II, or bronchial epithelial cells) to CFTR-regulated fluid transport is unknown. In this study we determined whether the CFTR gene is expressed in human lung alveolar epithelial type II (AT II) cells and whether the CFTR chloride channel contributes to cAMP-regulated fluid transport in cultured human AT II cells. Human AT II cells were isolated and cultured on collagen I-coated Transwell membranes for 120-144 h with an air-liquid interface. The cultured cells retained typical AT II-like features based on morphologic studies. Net basal fluid transport was 0.9+/-0.1 mul.cm-2.h-1 and increased to 1.35+/-0.11 mul.cm-2.h-1 (mean+/-SE, n=18, P<0.05) by stimulation with cAMP agonists. The CFTR inhibitor, CFTRinh-172, inhibited cAMP stimulated but not basal fluid transport. In short-circuit current (Isc) studies with an apical-to-basolateral transepithelial Cl- gradient, apical application of CFTRinh-172 reversed the forskolin-induced decrease in Isc. Real time RT-PCR demonstrated CFTR transcript expression in human AT II cells at a level similar to that in airway epithelial cells. We conclude that CFTR is expressed in cultured human AT II cells and may contribute to cAMP-regulated apical-basolateral fluid transport
Protein clearance from the air spaces and lungs of unanesthetized sheep over 144 h
No full text We studied the rate, the routes, and the mechanisms for protein clearance from the air spaces and lungs of 20 unanesthetized sheep over 144 h. We instilled 100 ml of autologous serum labeled with 125I-albumin into one lung. At the end of 24, 48, 96, or 144 h, the lungs were removed and the residual native protein and 125I-albumin in the air spaces were determined by bronchoalveolar lavage. Also the fraction of the instilled 125I-albumin remaining in the rest of the lung was measured in the lung homogenate. Clearance of the 125I-albumin from the lung into the plasma, lymph, thyroid, urine, and feces was also determined. The removal of both the 125I-albumin and the native protein from the air spaces was slow, following a monoexponential decline. The removal rate of the 125I-albumin from the air spaces was slightly but significantly faster (1.6%/h) than the clearance rate of the native protein (0.9%/h). Clearance of the 125I-albumin from the lung also followed a slow monoexponential decline at a rate of 1.4%/h. At all time periods, 75% of the 125I-albumin remaining in the lung was located in the air spaces, thus indicating that the pulmonary epithelium is the principal barrier to protein clearance from the normal lung. Macrophages appeared to play a minor role in alveolar protein clearance because the quantity of 125I-albumin present in the phagocytic cells in the air spaces was less than 1% of the instilled 125I-albumin at all time periods. However, macrophages may play some role in protein clearance after 48 h because we visualized phagolysosomes in macrophages, and there was an increase in free iodine in lung lavage, urine, thyroid, and feces after 48 h. However, gel electrophoretic studies showed that most of the 125I-albumin was cleared from the lung as an intact molecule, although only 24.7 +/- 4.7% of the 125I-albumin was cleared by the lymphatics. </jats:p
Measurement of the Decay Distribution of
No full textandua f , J. Ludemann b , H. Matthay b , R. McCrady n , J. Meier g , C.A. Meyer n , L. Montanet f , R. Ouared f , F. Ould-Saada p , K. Peters b , C. Pietra p , C.N. Pinder e , G. Pinter d , C. Regenfus l , J. Reißmann g , S. Resag c , W. Roethel l , P. Schmidt g , I. Scott i , R. Seibert g , S. Spanier p , H. Stock b , C. Straßburger c , U. Strohbusch g , M. Suffert o , U. Thoma c , M. Tischhauser h , D. Urner p , C. Volcker l , F. Walter k , D. Walther<F
Crystal Barrel Collaboration A. Abele
No full textM. Kunze b , M. Lakata a , R. Landua f , J. Ludemann b , H. Matthay b , R. McCrady n , J. Meier g , C.A. Meyer n , L. Montanet f , A. Noble p;4 , R. Ouared f , F. Ould-Saada p , K. Peters b , C.N. Pinder e , G. Pinter d , C. Regenfus l , J. Reißmann g , S. Resag c , W. Roethel l , P. Schmidt g , I. Scott i , R. Seibert g , S. Spanier p , H. Stock b , C. Straßburger c , U. Strohbusch g , M. Suffert o , U. Thoma c , M. Tischhauser h , D. Urner
The neuronal guidance protein netrin-1 reduces alveolar inflammation in a porcine model of acute lung injury
No full textIntroduction: Acute lung injury (ALI) is an inflammatory disorder of pulmonary or extrapulmonary origin. We have previously demonstrated that netrin-1 dampens murine ALI, and in an attempt to advance this finding into future clinical practice we evaluated whether netrin-1 would reduce alveolar inflammation during porcine ALI. Methods: This was a controlled in vivo experimental study in pigs. We induced ALI through lipoploysaccharide (LPS) infusion (50 micro g/kg) for 2 hours. Following this, we exposed animals to either vehicle, intravenous netrin-1 (netrin-1 i.v.) or inhaled netrin-1 (netrin-1 inh.). Serum samples and bronchoalveolar lavage (BAL) were obtained to determine levels of tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, interleukin-6 and interleukin-8 at baseline and 6 hours following treatment. Myeloperoxidase activity (MPO) and protein levels were determined in the BAL, and tissue samples were obtained for histological evaluation. Finally, animals were scanned with spiral CT. Results: Following LPS infusion, animals developed acute pulmonary injury. Serum levels of TNF-alpha and IL-6 were significantly reduced in the netrin-1 i.v. group. BAL demonstrated significantly reduced cytokine levels 6 hours post-netrin-1 treatment (TNF-alpha: vehicle 633 ± 172 pg/ml, netrin-1 i.v. 84 ± 5 pg/ml, netrin-1 inh. 168 ± 74 pg/ml; both P < 0.05). MPO activity and protein content were significantly reduced in BAL samples from netrin-1-treated animals. Histological sections confirmed reduced inflammatory changes in the netrin-1-treated animals. Computed tomography corroborated reduced pulmonary damage in both netrin-1-treated groups. Conclusions: We conclude that treatment with the endogenous anti-inflammatory protein netrin-1 reduces pulmonary inflammation during the initial stages of ALI and should be pursued as a future therapeutic option
Pp Annihilation At Rest Into
No full textMatthay b , M. Merkel j 9 , J.P. Merlo j , C.A. Meyer l , L. Montanet e , A. Noble n , F. Ould-Saada n , K. Peters b , C.N. Pinder d , G. Pinter c , S. Ravndal b10 , J. Salk b , A.H. Sanjari h 11 , E. Schafer j , B. Schmid n 12 , P. Schmidt f , S. Spanier j , C. Straßburger j 13 , U. Strohbusch f , M. Suffert m , D. Urner n , C.Volker k , F. Walter f , D. Walther b , U. Wiedner f , N. Winter g , J. Zoll e , B.S. Zou h , C. Zupancic k a University of Cal
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