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Escobar‐Salom M, Torrens G, Jordana‐Lluch E, Oliver A, Juan C. Mammals' humoral immune proteins and peptides targeting the bacterial envelope: from natural protection to therapeutic applications against multidrug‐resistant
Gram
‐negatives. Biol Rev Camb Philos Soc 2022; 97:1005-1037. [PMID: 35043558 PMCID: PMC9304279 DOI: 10.1111/brv.12830] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 12/12/2021] [Accepted: 12/15/2021] [Indexed: 12/11/2022]
Abstract
Mammalian innate immunity employs several humoral ‘weapons’ that target the bacterial envelope. The threats posed by the multidrug‐resistant ‘ESKAPE’ Gram‐negative pathogens (Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) are forcing researchers to explore new therapeutic options, including the use of these immune elements. Here we review bacterial envelope‐targeting (peptidoglycan and/or membrane‐targeting) proteins/peptides of the mammalian immune system that are most likely to have therapeutic applications. Firstly we discuss their general features and protective activity against ESKAPE Gram‐negatives in the host. We then gather, integrate, and discuss recent research on experimental therapeutics harnessing their bactericidal power, based on their exogenous administration and also on the discovery of bacterial and/or host targets that improve the performance of this endogenous immunity, as a novel therapeutic concept. We identify weak points and knowledge gaps in current research in this field and suggest areas for future work to obtain successful envelope‐targeting therapeutic options to tackle the challenge of antimicrobial resistance.
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Affiliation(s)
- María Escobar‐Salom
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
| | - Gabriel Torrens
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
| | - Elena Jordana‐Lluch
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
| | - Antonio Oliver
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
| | - Carlos Juan
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
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Tripathi A, Kumar B, Sagi SSK. Hypoxia-mediated alterations in pulmonary surfactant protein expressions: Beneficial effects of quercetin prophylaxis. Respir Physiol Neurobiol 2021; 291:103695. [PMID: 34052411 DOI: 10.1016/j.resp.2021.103695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 03/26/2021] [Accepted: 05/17/2021] [Indexed: 10/21/2022]
Abstract
We have compared the prophylactic efficacies of quercetin and salbutamol in preventing pulmonary surfactants oxidation under hypoxia. Male SD rats supplemented orally with quercetin (50 mg/Kg BW) and salbutamol (2 mg/Kg BW) were exposed to hypobaric hypoxia (7,620 m for 6 h). Hypoxia-mediated elevation in oxidative stress, inflammation, and extravasations of LDH & albumin content in BALF of rats were assessed. Western blotting and mRNA studies determined the differential expressions of Nrf-2, HO-1, and associated surfactant proteins (SP-A, SP-B, SP-C, & SP-D) in rat lungs. Later, the lung configuration under hypoxia was assessed histopathologically. Quercetin and salbutamol pretreatment considerably restored the expressions of Nrf-2, HO-1, and surfactant proteins to normal by attenuating the increase in oxidative stress, inflammation, and extravasations of plasma proteins in the animals under hypoxia. The histopathology has also evidenced the protective effect of quercetin in retaining normal lung architecture under hypoxia over salbutamol. The present study indicates the effectiveness of quercetin prophylaxis in preventing pulmonary surfactants oxidation under hypoxia over salbutamol.
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Affiliation(s)
- Ankit Tripathi
- Nutrition Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi, 110054, India.
| | - Bhuvnesh Kumar
- Nutrition Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi, 110054, India.
| | - Sarada S K Sagi
- Nutrition Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi, 110054, India.
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Mathew T, Sarada SKS. Intonation of Nrf2 and Hif1-α pathway by curcumin prophylaxis: A potential strategy to augment survival signaling under hypoxia. Respir Physiol Neurobiol 2018; 258:12-24. [PMID: 30268739 DOI: 10.1016/j.resp.2018.09.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 09/22/2018] [Accepted: 09/24/2018] [Indexed: 01/30/2023]
Abstract
BACKGROUND Pulmonary surfactant oxidation leads to alveolar collapse- a condition often noticed in high altitude pulmonary edema (HAPE). The present study was aimed to determine the effect of curcumin prophylaxis in augmenting the phase II antioxidant enzymes and surfactant proteins expression in enabling the pulmonary surfactant homeostasis under hypoxia. METHODS A549 cells were exposed to 3% hypoxia for different time durations (1 h, 3 h, 6 h, 12 h and 24 h). The Cells were pretreated (1 h) with 10 μM curcumin and exposed to hypoxia. The in-vivo results were extrapolated into in-vivo system using male Sprague Dawley rats, exposed to a stimulated altitude of 7620 m for 6 h. The rats were supplemented with curcumin (50 mg/kgBW) 1 h prior to hypoxia exposure. RESULTS Results showed that, the expression of surfactant proteins (SPs) A and B decreased from 3 h of hypoxic exposure, whereas expression of SP-C and SP-D proteins were increased within 1 h of hypoxic exposure over control cells. Hypoxic exposure resulted into significant increase in protein and lipid peroxidation (p < 0.001), reduced levels of antioxidants (GSH, GPx and SOD) (p < 0.001) along with significant down regulation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and Heme oxygenase-1 (HO-1) in A549 cells over control. However, the curcumin supplementation both in-vitro and in-vivo resulted into increased expressions of HO-1 and Nrf2 significantly (p < 0.001), which enabled the cells in balanced expression of SPs with reduced levels of oxidants. Further curcumin significantly enhanced the levels of antioxidant enzymes in BALF along with stabilized expression of hypoxia inducible factor 1(HIF-1α) followed by reduced expression of vascular endothelial growth factor (VEGF) in lungs of rats. The immunohistochemistry observations provided substantial evidence of enhanced surfactant protein expressions in lungs of curcumin administered hypoxia exposed rats. CONCLUSION These results indicate that curcumin augment survival signaling by reinforcing the induction of phase II antioxidant enzymes thereby enabling the pulmonary surfactant homeostasis under hypoxia.
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Affiliation(s)
- Titto Mathew
- Haematology Division, Defence Institute of Physiology and Allied Sciences, Timarpur, Delhi- 54, India
| | - S K S Sarada
- Haematology Division, Defence Institute of Physiology and Allied Sciences, Timarpur, Delhi- 54, India.
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4
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Vieira F, Kung JW, Bhatti F. Structure, genetics and function of the pulmonary associated surfactant proteins A and D: The extra-pulmonary role of these C type lectins. Ann Anat 2017; 211:184-201. [PMID: 28351530 DOI: 10.1016/j.aanat.2017.03.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Revised: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 10/19/2022]
Abstract
The collectins family encompasses several collagenous Ca2+-dependent defense lectins that are described as pathogen recognition molecules. They play an important role in both adaptive and innate immunity. Surfactant proteins A and D are two of these proteins which were initially discovered in association with surfactant in the pulmonary system. The structure, immune and inflammatory functions, and genetic variations have been well described in relation to their roles, function and pathophysiology in the pulmonary system. Subsequently, these proteins have been discovered in a wide range of other organs and organ systems. The role of these proteins outside the pulmonary system is currently an active area of research. This review intends to provide a current overview of the genetics, structure and extra-pulmonary functions of the surfactant collectin proteins.
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Affiliation(s)
- Frederico Vieira
- Neonatal Perinatal Medicine, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States.
| | - Johannes W Kung
- Neonatal Perinatal Medicine, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States.
| | - Faizah Bhatti
- Neonatal Perinatal Medicine, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States; Department of Ophthalmology, Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States; Oklahoma Center for Neurosciences, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States.
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Coya JM, Akinbi HT, Sáenz A, Yang L, Weaver TE, Casals C. Natural Anti-Infective Pulmonary Proteins: In Vivo Cooperative Action of Surfactant Protein SP-A and the Lung Antimicrobial Peptide SP-BN. THE JOURNAL OF IMMUNOLOGY 2015; 195:1628-36. [PMID: 26163587 DOI: 10.4049/jimmunol.1500778] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 06/10/2015] [Indexed: 12/19/2022]
Abstract
The anionic antimicrobial peptide SP-B(N), derived from the N-terminal saposin-like domain of the surfactant protein (SP)-B proprotein, and SP-A are lung anti-infective proteins. SP-A-deficient mice are more susceptible than wild-type mice to lung infections, and bacterial killing is enhanced in transgenic mice overexpressing SP-B(N). Despite their potential anti-infective action, in vitro studies indicate that several microorganisms are resistant to SP-A and SP-B(N). In this study, we test the hypothesis that these proteins act synergistically or cooperatively to strengthen each other's microbicidal activity. The results indicate that the proteins acted synergistically in vitro against SP-A- and SP-B(N)-resistant capsulated Klebsiella pneumoniae (serotype K2) at neutral pH. SP-A and SP-B(N) were able to interact in solution (Kd = 0.4 μM), which enabled their binding to bacteria with which SP-A or SP-B(N) alone could not interact. In vivo, we found that treatment of K. pneumoniae-infected mice with SP-A and SP-B(N) conferred more protection against K. pneumoniae infection than each protein individually. SP-A/SP-B(N)-treated infected mice showed significant reduction of bacterial burden, enhanced neutrophil recruitment, and ameliorated lung histopathology with respect to untreated infected mice. In addition, the concentrations of inflammatory mediators in lung homogenates increased early in infection in contrast with the weak inflammatory response of untreated K. pneumoniae-infected mice. Finally, we found that therapeutic treatment with SP-A and SP-B(N) 6 or 24 h after bacterial challenge conferred significant protection against K. pneumoniae infection. These studies show novel anti-infective pathways that could drive development of new strategies against pulmonary infections.
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Affiliation(s)
- Juan Manuel Coya
- Department of Biochemistry and Molecular Biology I, Complutense University of Madrid, 28040 Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Instituto de Salud Carlos III, 28029 Madrid, Spain; and
| | - Henry T Akinbi
- Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH 45229
| | - Alejandra Sáenz
- Department of Biochemistry and Molecular Biology I, Complutense University of Madrid, 28040 Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Instituto de Salud Carlos III, 28029 Madrid, Spain; and
| | - Li Yang
- Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH 45229
| | - Timothy E Weaver
- Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH 45229
| | - Cristina Casals
- Department of Biochemistry and Molecular Biology I, Complutense University of Madrid, 28040 Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Instituto de Salud Carlos III, 28029 Madrid, Spain; and
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Prost M, Canaple L, Samarut J, Hasserodt J. Tagging Live Cells that Express Specific Peptidase Activity with Solid-State Fluorescence. Chembiochem 2014; 15:1413-7. [DOI: 10.1002/cbic.201402091] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Indexed: 11/11/2022]
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Tran HB, Ahern J, Hodge G, Holt P, Dean MM, Reynolds PN, Hodge S. Oxidative stress decreases functional airway mannose binding lectin in COPD. PLoS One 2014; 9:e98571. [PMID: 24901869 PMCID: PMC4047017 DOI: 10.1371/journal.pone.0098571] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 05/05/2014] [Indexed: 01/22/2023] Open
Abstract
We have previously established that a defect in the ability of alveolar macrophages (AM) to phagocytose apoptotic cells (efferocytosis) and pathogens is a potential therapeutic target in COPD. We further showed that levels of mannose binding lectin (MBL; required for effective macrophage phagocytic function) were reduced in the airways but not circulation of COPD patients. We hypothesized that increased oxidative stress in the airway could be a cause for such disturbances. We therefore studied the effects of oxidation on the structure of the MBL molecule and its functional interactions with macrophages. Oligomeric structure of plasma derived MBL (pdMBL) before and after oxidation (oxMBL) with 2,2′-azobis(2-methylpropionamidine)dihydrochroride (AAPH) was investigated by blue native PAGE. Macrophage function in the presence of pd/oxMBL was assessed by measuring efferocytosis, phagocytosis of non-typeable Haemophilus influenzae (NTHi) and expression of macrophage scavenger receptors. Oxidation disrupted higher order MBL oligomers. This was associated with changed macrophage function evident by a significantly reduced capacity to phagocytose apoptotic cells and NTHi in the presence of oxMBL vs pdMBL (eg, NTHi by 55.9 and 27.0% respectively). Interestingly, oxidation of MBL significantly reduced macrophage phagocytic ability to below control levels. Flow cytometry and immunofluorescence revealed a significant increase in expression of macrophage scavenger receptor (SRA1) in the presence of pdMBL that was abrogated in the presence of oxMBL. We show the pulmonary macrophage dysfunction in COPD may at least partially result from an oxidative stress-induced effect on MBL, and identify a further potential therapeutic strategy for this debilitating disease.
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Affiliation(s)
- Hai B. Tran
- Lung Research, Hanson Institute and Department Thoracic Medicine, Royal Adelaide Hospital, Adelaide, South Australia, Australia
- * E-mail:
| | - Jessica Ahern
- Lung Research, Hanson Institute and Department Thoracic Medicine, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Greg Hodge
- Lung Research, Hanson Institute and Department Thoracic Medicine, Royal Adelaide Hospital, Adelaide, South Australia, Australia
- Department of Medicine, University of Adelaide, Adelaide, South Australia, Australia
| | - Phillip Holt
- Lung Research, Hanson Institute and Department Thoracic Medicine, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Melinda M. Dean
- Research and Development, Australian Red Cross Blood Service, Brisbane, Queensland, Australia
| | - Paul N. Reynolds
- Lung Research, Hanson Institute and Department Thoracic Medicine, Royal Adelaide Hospital, Adelaide, South Australia, Australia
- Department of Medicine, University of Adelaide, Adelaide, South Australia, Australia
| | - Sandra Hodge
- Lung Research, Hanson Institute and Department Thoracic Medicine, Royal Adelaide Hospital, Adelaide, South Australia, Australia
- Department of Medicine, University of Adelaide, Adelaide, South Australia, Australia
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Phelps DS, Umstead TM, Silveyra P, Hu S, Wang G, Floros J. Differences in the alveolar macrophage proteome in transgenic mice expressing human SP-A1 and SP-A2. ACTA ACUST UNITED AC 2013; 1:2-26. [PMID: 24729982 DOI: 10.14302/issn.2326-0793.jpgr-12-207] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Surfactant protein A (SP-A) plays a number of roles in lung host defense and innate immunity. There are two human genes, SFTPA1 and SFTPA2, and evidence indicates that the function of SP-A1 and SP-A2 proteins differ in several respects. To investigate the impact of SP-A1 and SP-A2 on the alveolar macrophage (AM) phenotype, we generated humanized transgenic (hTG) mice on the SP-A knockout (KO) background, each expressing human SP-A1 or SP-A2. Using two-dimensional difference gel electrophoresis (2D-DIGE) we studied the AM cellular proteome. We compared mouse lines expressing high levels of SPA1, high levels of SP-A2, low levels of SP-A1, and low levels of SP-A2, with wild type (WT) and SP-A KO mice. AM from mice expressing high levels of SP-A2 were the most similar to WT mice, particularly for proteins related to actin and the cytoskeleton, as well as proteins regulated by Nrf2. The expression patterns from mouse lines expressing higher levels of the transgenes were almost the inverse of one another - the most highly expressed proteins in SP-A2 exhibited the lowest levels in the SP-A1 mice and vice versa. The mouse lines where each expressed low levels of SP-A1 or SP-A2 transgene had very similar protein expression patterns suggesting that responses to low levels of SP-A are independent of SP-A genotype, whereas the responses to higher amounts of SP-A are genotype-dependent. Together these observations indicate that in vivo exposure to SP-A1 or SP-A2 differentially affects the proteomic expression of AMs, with SP-A2 being more similar to WT.
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Affiliation(s)
- David S Phelps
- C enter for H ost defense, I nflammation, and L ung D isease (CHILD) Research and Departments of Pediatrics, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Todd M Umstead
- C enter for H ost defense, I nflammation, and L ung D isease (CHILD) Research and Departments of Pediatrics, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Patricia Silveyra
- C enter for H ost defense, I nflammation, and L ung D isease (CHILD) Research and Departments of Pediatrics, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Sanmei Hu
- C enter for H ost defense, I nflammation, and L ung D isease (CHILD) Research and Departments of Pediatrics, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Guirong Wang
- C enter for H ost defense, I nflammation, and L ung D isease (CHILD) Research and Departments of Pediatrics, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Joanna Floros
- C enter for H ost defense, I nflammation, and L ung D isease (CHILD) Research and Departments of Pediatrics, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA. ; Obstetrics and Gynecology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
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Fang CS, Wang YC, Zhang TH, Wu J, Wang W, Wang C, Zhang MY. Clinical significance of serum lipids in idiopathic pulmonary alveolar proteinosis. Lipids Health Dis 2012; 11:12. [PMID: 22252101 PMCID: PMC3271981 DOI: 10.1186/1476-511x-11-12] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2011] [Accepted: 01/17/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND It is well known that pulmonary alveolar proteinosis(PAP) is characterised by accumulation of surfactant lipids and proteins within airspaces. However, few previous data describe the serum lipid levels associated with PAP. MATERIALS AND METHODS We retrospectively reviewed 25 patients with idiopathic PAP(iPAP). The serum lipid levels of patients with idiopathic PAP were compared with those of the healthy volunteers. In patients and healthy subjects, the LDL-C/HDL-C ratios were 2.94 ± 1.21 and 1.60 ± 0.70, respectively (p < 0.001), HDL-C were 1.11 ± 0.27 and 1.71 ± 0.71 respectively (p < 0.001). The values of LDL-C correlated significantly with those of PaO2 and PA-aO2 (r = -0.685, p = 0.003, and r = 0.688, p = 0.003, respectively). The values of LDL-C/HDL-C ratios also correlated with PaO2 levels and PA-aO2 levels (r = -0.698, p = 0.003, and r = 0.653, p = 0.006, respectively). 11 and 13 patients experienced respectively a decline in TC and LDL-C levels following whole lung lavage(WLL), the median decline was 0.71 mmol/L(p < 0.009) and 0.47 mmol/L(p < 0.003), respectively. CONCLUSIONS the serum lipid levels, especially the levels of LDL-C and LDL-C/HDL-C, may reflect the severity of the disease in PAP patients, and predict the therapeutic effect of WLL.
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Affiliation(s)
- Cun S Fang
- Nine department of Respiratory Medicine, Nanjing Chest Hospital, Nanjing, P.R. China
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Kuang Z, Hao Y, Walling BE, Jeffries JL, Ohman DE, Lau GW. Pseudomonas aeruginosa elastase provides an escape from phagocytosis by degrading the pulmonary surfactant protein-A. PLoS One 2011; 6:e27091. [PMID: 22069491 PMCID: PMC3206073 DOI: 10.1371/journal.pone.0027091] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 10/10/2011] [Indexed: 01/13/2023] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen that causes both acute pneumonitis in immunocompromised patients and chronic lung infections in individuals with cystic fibrosis and other bronchiectasis. Over 75% of clinical isolates of P. aeruginosa secrete elastase B (LasB), an elastolytic metalloproteinase that is encoded by the lasB gene. Previously, in vitro studies have demonstrated that LasB degrades a number of components in both the innate and adaptive immune systems. These include surfactant proteins, antibacterial peptides, cytokines, chemokines and immunoglobulins. However, the contribution of LasB to lung infection by P. aeruginosa and to inactivation of pulmonary innate immunity in vivo needs more clarification. In this study, we examined the mechanisms underlying enhanced clearance of the ΔlasB mutant in mouse lungs. The ΔlasB mutant was attenuated in virulence when compared to the wild-type strain PAO1 during lung infection in SP-A+/+ mice. However, the ΔlasB mutant was as virulent as PAO1 in the lungs of SP-A⁻/⁻ mice. Detailed analysis showed that the ΔlasB mutant was more susceptible to SP-A-mediated opsonization but not membrane permeabilization. In vitro and in vivo phagocytosis experiments revealed that SP-A augmented the phagocytosis of ΔlasB mutant bacteria more efficiently than the isogenic wild-type PAO1. The ΔlasB mutant was found to have a severely reduced ability to degrade SP-A, consequently making it unable to evade opsonization by the collectin during phagocytosis. These results suggest that P. aeruginosa LasB protects against SP-A-mediated opsonization by degrading the collectin.
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Affiliation(s)
- Zhizhou Kuang
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Yonghua Hao
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Brent E. Walling
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Jayme L. Jeffries
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Dennis E. Ohman
- Department of Microbiology and Immunology, Virginia Commonwealth University School of Medicine, Richmond, Virginia, United States of America
| | - Gee W. Lau
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
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Phelps DS, Umstead TM, Quintero OA, Yengo CM, Floros J. In vivo rescue of alveolar macrophages from SP-A knockout mice with exogenous SP-A nearly restores a wild type intracellular proteome; actin involvement. Proteome Sci 2011; 9:67. [PMID: 22035134 PMCID: PMC3219558 DOI: 10.1186/1477-5956-9-67] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 10/28/2011] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Mice lacking surfactant protein-A (SP-A-/-; knockout; KO) exhibit increased vulnerability to infection and injury. Although many bronchoalveolar lavage (BAL) protein differences between KO and wild-type (WT) are rapidly reversed in KO after infection, their clinical course is still compromised. We studied the impact of SP-A on the alveolar macrophage (AM) proteome under basal conditions. Male SP-A KO mice were SP-A-treated (5 micrograms/mouse) and sacrificed in 6 or 18 hr. The AM proteomes of KO, SP-A-treated KO, and WT mice were studied by 2D-DIGE coupled with MALDI-ToF/ToF and AM actin distribution was examined by phalloidon staining. RESULTS We observed: a) significant differences from KO in WT or exogenous SP-A-treated in 45 of 76 identified proteins (both increases and decreases). These included actin-related/cytoskeletal proteins (involved in motility, phagocytosis, endocytosis), proteins of intracellular signaling, cell differentiation/regulation, regulation of inflammation, protease/chaperone function, and proteins related to Nrf2-mediated oxidative stress response pathway; b) SP-A-induced changes causing the AM proteome of the KO to resemble that of WT; and c) that SP-A treatment altered cell size and F-actin distribution. CONCLUSIONS These differences are likely to enhance AM function. The observations show for the first time that acute in vivo SP-A treatment of KO mice, under basal or unstimulated conditions, affects the expression of multiple AM proteins, alters F-actin distribution, and can restore much of the WT phenotype. We postulate that the SP-A-mediated expression profile of the AM places it in a state of "readiness" to successfully conduct its innate immune functions and ensure lung health.
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Affiliation(s)
- David S Phelps
- Center for Host defense, Inflammation, and Lung Disease (CHILD) Research and Department of Pediatrics, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA.
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Wu H, Suzuki T, Carey B, Trapnell BC, McCormack FX. Keratinocyte growth factor augments pulmonary innate immunity through epithelium-driven, GM-CSF-dependent paracrine activation of alveolar macrophages. J Biol Chem 2011; 286:14932-40. [PMID: 21343299 PMCID: PMC3083236 DOI: 10.1074/jbc.m110.182170] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2010] [Revised: 02/01/2011] [Indexed: 11/06/2022] Open
Abstract
Keratinocyte growth factor (KGF) is an epithelial mitogen that has been reported to protect the lungs from a variety of insults. In this study, we tested the hypothesis that KGF augments pulmonary host defense. We found that a single dose of intrapulmonary KGF enhanced the clearance of Escherichia coli or Pseudomonas aeruginosa instilled into the lungs 24 h later. KGF augmented the recruitment, phagocytic activity, and oxidant responses of alveolar macrophages, including lipopolysaccharide-stimulated nitric oxide release and zymosan-induced superoxide production. Less robust alveolar macrophage recruitment and activation was observed in mice treated with intraperitoneal KGF. KGF treatment was associated with increased levels of MIP1γ, LIX, VCAM, IGFBP-6, and GM-CSF in the bronchoalveolar lavage fluid. Of these, only GM-CSF recapitulated in vitro the macrophage activation phenotype seen in the KGF-treated animals. The KGF-stimulated increase in GM-CSF levels in lung tissue and alveolar lining fluid arose from the epithelium, peaked within 1 h, and was associated with STAT5 phosphorylation in alveolar macrophages, consistent with epithelium-driven paracrine activation of macrophage signaling through the KGF receptor/GM-CSF/GM-CSF receptor/JAK-STAT axis. Enhanced bacterial clearance did not occur in response to KGF administration in GM-CSF(-/-) mice, or in mice treated with a neutralizing antibody to GM-CSF. We conclude that KGF enhances alveolar host defense through GM-CSF-stimulated macrophage activation. KGF administration may constitute a promising therapeutic strategy to augment innate immune defenses in refractory pulmonary infections.
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Affiliation(s)
- Huixing Wu
- From the Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, and
| | - Takuji Suzuki
- Division of Pulmonary Biology, Department of Pediatrics, Children's Hospital Medical Center, The University of Cincinnati, Cincinnati, Ohio 45267-0564
| | - Brenna Carey
- Division of Pulmonary Biology, Department of Pediatrics, Children's Hospital Medical Center, The University of Cincinnati, Cincinnati, Ohio 45267-0564
| | - Bruce C. Trapnell
- Division of Pulmonary Biology, Department of Pediatrics, Children's Hospital Medical Center, The University of Cincinnati, Cincinnati, Ohio 45267-0564
| | - Francis X. McCormack
- From the Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, and
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13
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Awasthi S, Madhusoodhanan R, Wolf R. Surfactant protein-A and toll-like receptor-4 modulate immune functions of preterm baboon lung dendritic cell precursor cells. Cell Immunol 2011; 268:87-96. [PMID: 21439559 PMCID: PMC3104394 DOI: 10.1016/j.cellimm.2011.02.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Accepted: 02/28/2011] [Indexed: 01/04/2023]
Abstract
Lung infections are important risk factors for an increased morbidity and mortality in prematurely-delivered babies. Immaturity of the innate immune components makes them extremely susceptible to infection. Recently, we isolated lung dendritic cell (DC)-precursor cells from preterm fetal baboons. The isolated cells were found to be defective in phagocytosing Escherichia coli under basal conditions. In this study, we investigated the effects of exogenously-added purified native lung surfactant protein (SP)-A and recombinant toll-like receptor (TLR)-4-MD2 proteins on phagocytic uptake and cytokine secreting ability of fetal baboon lung DC-precursor cells. The cells were pulsed with SP-A and/or TLR4-MD2 proteins and the phagocytic function was investigated by incubating the cells with fluorescent-labeled E. coli bioparticles and analyzed by spectrofluorometry. The amounts of TNF-α secreted in cell-free supernatants were measured by ELISA. Our results demonstrate that SP-A and TLR4-MD2 proteins, whether added alone or together, induce phagocytosis of E. coli (p<0.05). The SP-A does not affect TNF-α secretion, while the TLR4-MD2 protein induces TNF-α. However, simultaneous addition of SP-A with TLR4-MD2 protein reduces the TLR4-MD2-protein induced TNF-α to basal level. In conclusion, our results indicate that an exogenous administration of SP-A can potentially induce phagocytic activity and anti-inflammatory effect in preterm babies, and help control infection and inflammation.
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Affiliation(s)
- Shanjana Awasthi
- Department of Pharmaceutical Sciences, University of Oklahoma Health Science Center, Oklahoma City, OK 73117, USA.
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14
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Kuang Z, Hao Y, Hwang S, Zhang S, Kim E, Akinbi HT, Schurr MJ, Irvin RT, Hassett DJ, Lau GW. The Pseudomonas aeruginosa flagellum confers resistance to pulmonary surfactant protein-A by impacting the production of exoproteases through quorum-sensing. Mol Microbiol 2011; 79:1220-35. [PMID: 21205009 DOI: 10.1111/j.1365-2958.2010.07516.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Surfactant protein-A (SP-A) is an important antimicrobial protein that opsonizes and permeabilizes membranes of microbial pathogens in mammalian lungs. Previously, we have shown that Pseudomonas aeruginosa flagellum-deficient mutants are preferentially cleared in the lungs of wild-type mice by SP-A-mediated membrane permeabilization, and not by opsonization. In this study, we report a flagellum-mediated mechanism of P. aeruginosa resistance to SP-A. We discovered that flagellum-deficient (ΔfliC) bacteria are unable to produce adequate amounts of exoproteases to degrade SP-A in vitro and in vivo, leading to its preferential clearance in the lungs of SP-A(+/+) mice. In addition, ΔfliC bacteria failed to degrade another important lung antimicrobial protein lysozyme. Detailed analyses showed that ΔfliC bacteria are unable to upregulate the transcription of lasI and rhlI genes, impairing the production of homoserine lactones necessary for quorum-sensing, an important virulence process that regulates the production of multiple exoproteases. Thus, reduced ability of ΔfliC bacteria to quorum-sense attenuates production of exoproteases and limits degradation of SP-A, thereby conferring susceptibility to this major pulmonary host defence protein.
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Affiliation(s)
- Zhizhou Kuang
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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15
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Chroneos ZC, Sever-Chroneos Z, Shepherd VL. Pulmonary surfactant: an immunological perspective. Cell Physiol Biochem 2009; 25:13-26. [PMID: 20054141 DOI: 10.1159/000272047] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/16/2009] [Indexed: 11/19/2022] Open
Abstract
Pulmonary surfactant has two crucial roles in respiratory function; first, as a biophysical entity it reduces surface tension at the air water interface, facilitating gas exchange and alveolar stability during breathing, and, second, as an innate component of the lung's immune system it helps maintain sterility and balance immune reactions in the distal airways. Pulmonary surfactant consists of 90% lipids and 10% protein. There are four surfactant proteins named SP-A, SP-B, SP-C, and SP-D; their distinct interactions with surfactant phospholipids are necessary for the ultra-structural organization, stability, metabolism, and lowering of surface tension. In addition, SP-A and SP-D bind pathogens, inflict damage to microbial membranes, and regulate microbial phagocytosis and activation or deactivation of inflammatory responses by alveolar macrophages. SP-A and SP-D, also known as pulmonary collectins, mediate microbial phagocytosis via SP-A and SP-D receptors and the coordinated induction of other innate receptors. Several receptors (SP-R210, CD91/calreticulin, SIRPalpha, and toll-like receptors) mediate the immunological functions of SP-A and SP-D. However, accumulating evidence indicate that SP-B and SP-C and one or more lipid constituents of surfactant share similar immuno-regulatory properties as SP-A and SP-D. The present review discusses current knowledge on the interaction of surfactant with lung innate host defense.
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Affiliation(s)
- Zissis C Chroneos
- The Center of Biomedical Research, University of Texas Health Science Center at Tyler, Tyler, TX 75708-3154, USA.
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16
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Haque R, Umstead TM, Freeman WM, Floros J, Phelps DS. The impact of surfactant protein-A on ozone-induced changes in the mouse bronchoalveolar lavage proteome. Proteome Sci 2009; 7:12. [PMID: 19323824 PMCID: PMC2666657 DOI: 10.1186/1477-5956-7-12] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Accepted: 03/26/2009] [Indexed: 12/22/2022] Open
Abstract
Background Ozone is a major component of air pollution. Exposure to this powerful oxidizing agent can cause or exacerbate many lung conditions, especially those involving innate immunity. Surfactant protein-A (SP-A) plays many roles in innate immunity by participating directly in host defense as it exerts opsonin function, or indirectly via its ability to regulate alveolar macrophages and other innate immune cells. The mechanism(s) responsible for ozone-induced pathophysiology, while likely related to oxidative stress, are not well understood. Methods We employed 2-dimensional difference gel electrophoresis (2D-DIGE), a discovery proteomics approach, coupled with MALDI-ToF/ToF to compare the bronchoalveolar lavage (BAL) proteomes in wild type (WT) and SP-A knockout (KO) mice and to assess the impact of ozone or filtered air on the expression of BAL proteins. Using the PANTHER database and the published literature most identified proteins were placed into three functional groups. Results We identified 66 proteins and focused our analysis on these proteins. Many of them fell into three categories: defense and immunity; redox regulation; and protein metabolism, modification and chaperones. In response to the oxidative stress of acute ozone exposure (2 ppm; 3 hours) there were many significant changes in levels of expression of proteins in these groups. Most of the proteins in the redox group were decreased, the proteins involved in protein metabolism increased, and roughly equal numbers of increases and decreases were seen in the defense and immunity group. Responses between WT and KO mice were similar in many respects. However, the percent change was consistently greater in the KO mice and there were more changes that achieved statistical significance in the KO mice, with levels of expression in filtered air-exposed KO mice being closer to ozone-exposed WT mice than to filtered air-exposed WT mice. Conclusion We postulate that SP-A plays a role in reactive oxidant scavenging in WT mice and that its absence in the KO mice in the presence or absence of ozone exposure results in more pronounced, and presumably chronic, oxidative stress.
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Affiliation(s)
- Rizwanul Haque
- Penn State Center for Host defense, Inflammation, and Lung Disease (CHILD) Research and the Department of Pediatrics, Penn State College of Medicine, Hershey, PA, USA
| | - Todd M Umstead
- Penn State Center for Host defense, Inflammation, and Lung Disease (CHILD) Research and the Department of Pediatrics, Penn State College of Medicine, Hershey, PA, USA
| | - Willard M Freeman
- The Department of Pharmacology, Penn State College of Medicine, Hershey, PA, USA
| | - Joanna Floros
- Penn State Center for Host defense, Inflammation, and Lung Disease (CHILD) Research and the Department of Pediatrics, Penn State College of Medicine, Hershey, PA, USA.,The Department of Obstetrics and Gynecology, Penn State College of Medicine, Hershey, PA, USA
| | - David S Phelps
- Penn State Center for Host defense, Inflammation, and Lung Disease (CHILD) Research and the Department of Pediatrics, Penn State College of Medicine, Hershey, PA, USA
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17
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Umstead TM, Freeman WM, Chinchilli VM, Phelps DS. Age-related changes in the expression and oxidation of bronchoalveolar lavage proteins in the rat. Am J Physiol Lung Cell Mol Physiol 2009; 296:L14-29. [DOI: 10.1152/ajplung.90366.2008] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The incidence and severity of many lung diseases change with age. Some diseases, such as pneumonia, occur with increased frequency in children and the elderly. Proteins obtained by bronchoalveolar lavage (BAL) serve as the first line of defense against inhaled toxins and pathogens. Age-related changes in BAL protein expression and oxidative modification were examined in juvenile (1 mo), young adult (2 mo), and aged (18 mo) F344 rats using two-dimensional difference gel electrophoresis (2D-DIGE), matrix-assisted laser desorption ionization-time of flight/time of flight (MALDI-ToF/ToF) tandem mass spectrometry, and carbonyl immunoblotting. Using 2D-DIGE, we detected 563 protein spots, and MALDI-ToF/ToF identified 204 spots comprising 31 proteins; 21 changed significantly (17 increases) between juvenile and young adult or aged rats, but for 12 of these proteins, levels had a biphasic pattern, and levels in aged rats were less than in young adults. Relative carbonylation was determined by comparison of immunostaining with total protein staining on each oxidized protein blot. We found that aged rats had significantly increased oxidation in 13 proteins compared with juvenile rats. Many of the proteins altered in expression or oxidation level had functions in host defense, redox regulation, and protein metabolism. We speculate that low levels of expression of host defense proteins in juvenile rats and decreases in levels of these proteins between young adult and aged rats may predispose these groups to pneumonia. In addition, we have shown age-related increases in protein oxidation that may compromise host defense function in aged rats.
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18
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Surfactant-associated protein A provides critical immunoprotection in neonatal mice. Infect Immun 2007; 76:380-90. [PMID: 17967856 DOI: 10.1128/iai.01043-07] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The collectins surfactant-associated protein A (SP-A) and SP-D are components of innate immunity that are present before birth. Both proteins bind pathogens and assist in clearing infection. The significance of SP-A and SP-D as components of the neonatal immune system has not been investigated. To determine the role of SP-A and SP-D in neonatal immunity, wild-type, SP-A null, and SP-D null mice were bred in a bacterium-laden environment (corn dust bedding) or in a semisterile environment (cellulose fiber bedding). When reared in the corn dust bedding, SP-A null pups had significant mortality (P < 0.001) compared to both wild-type and SP-D null pups exposed to the same environment. The mortality of the SP-A null pups was associated with significant gastrointestinal tract pathology but little lung pathology. Moribund SP-A null newborn mice exhibited Bacillus sp. and Enterococcus sp. peritonitis. When the mother or newborn produced SP-A, newborn survival was significantly improved (P < 0.05) compared to the results when there was a complete absence of SP-A in both the mother and the pup. Significant sources of SP-A likely to protect a newborn include the neonatal lung and gastrointestinal tract but not the lactating mammary tissue of the mother. Furthermore, exogenous SP-A delivered by mouth to newborn SP-A null pups with SP-A null mothers improved newborn survival in the corn dust environment. Therefore, a lack of SP-D did not affect newborn survival, while SP-A produced by either the mother or the pup or oral exogenous SP-A significantly reduced newborn mortality associated with environmentally induced infection in SP-A null newborns.
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Abstract
PURPOSE OF REVIEW Recent articles of clinical and investigational interest on Gram-negative pneumonia, particularly hospital-acquired and ventilator-associated pneumonia, are reviewed. RECENT FINDINGS The high rate of respiratory infections due to Gram-negative bacteria in late-onset ventilator-associated pneumonia has been repeatedly documented. The predominant pathogens are Pseudomonas aeruginosa and Acinetobacter baumannii. On the other hand, the frequency of Gram-negative bacteria in community-acquired pneumonia and in early-onset ventilator-associated pneumonia is increasing. Patients with risk factors for infection with resistant pathogens should initially receive a combination therapy that covers a broad spectrum, and, as soon as the pathogen and the susceptibilities are available, treatment should be simplified to a more targeted one (with the possible exception of P. aeruginosa pneumonia). Adequate dosing is of great importance and the use of pharmacodynamic/pharmacokinetic principles when prescribing antibiotics increases effectiveness. The optimal duration of therapy remains unknown; several studies have supported the use of shorter courses of treatment. Alternative treatment approaches (e.g. vaccines) are under investigation. SUMMARY The increasing frequency of resistant Gram-negative bacteria and the shortage of newer antibiotics in the pipeline with activity against Gram-negative bacteria is of concern. Early effective antimicrobial treatment is a key for the resolution of infection and improved survival.
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Affiliation(s)
- Despoina Koulenti
- Critical Care Department, Joan XXIII University Hospital, University Rovira y Virgili/Institut PereVirgili, Tarragona, Spain
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20
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Kuzmenko AI, Wu H, McCormack FX. Pulmonary collectins selectively permeabilize model bacterial membranes containing rough lipopolysaccharide. Biochemistry 2006; 45:2679-85. [PMID: 16489761 PMCID: PMC3156245 DOI: 10.1021/bi0522652] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We have reported that Gram-negative organisms decorated with rough lipopolysaccharide (LPS) are particularly susceptible to the direct antimicrobial actions of the pulmonary collectins, surfactant proteins A (SP-A) and D (SP-D). In this study, we examined the lipid and LPS components required for the permeabilizing effects of the collectins on model bacterial membranes. Liposomes composed of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE), with or without rough Escherichia coli LPS (J5), smooth E. coli LPS (B5), or cholesterol, were loaded with self-quenching probes and exposed to native or oxidatively modified SP-A. Fluorescence that resulted from permeabilization of liposomes and diffusion of dyes was assessed by microscopy or fluorimetry. Human SP-A and melittin increased the permeability of J5 LPS/POPE liposomes, but not B5 LPS/POPE liposomes or control (POPE only) liposomes. At a human SP-A concentration of 100 microg/mL, the permeability of the J5 LPS/POPE membranes increased 4.4-fold (p < 0.02) compared to the control with no added SP-A. Rat SP-A and SP-D also permeabilized the J5-containing liposomes. Incorporation of cholesterol into J5 LPS/POPE liposomes at a POPE:cholesterol molar ratio of 1:0.15 blocked human SP-A or melittin-induced permeability (p < 0.05) compared to cholesterol-free liposomes. Exposure of human SP-A to surfactant lipid peroxidation blocked the permeabilizing activity of the protein. We conclude that SP-A permeabilizes phospholipid membranes in an LPS-dependent and rough LPS-specific manner, that the effect is neither SP-A- nor species-specific, and that oxidative damage to SP-A abolishes its membrane destabilizing properties. Incorporation of cholesterol into the membrane enhances resistance to permeabilization by SP-A, most likely by increasing the packing density and membrane rigidity.
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Affiliation(s)
| | | | - Francis X. McCormack
- Corresponding Author Footnote: Prof. Francis X. McCormack, University of Cincinnati, MSB Room 6053, 231 Albert Sabin Way, Cincinnati, OH 45267-0564, Tel. 513-558-4831, FAX 513-558-4858, E-mail:
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Starosta V, Rietschel E, Paul K, Baumann U, Griese M. Oxidative Changes of Bronchoalveolar Proteins in Cystic Fibrosis. Chest 2006; 129:431-437. [PMID: 16478863 DOI: 10.1378/chest.129.2.431] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Chronic bacterial infection and severe, polymorphonuclear neutrophil-dominated endobronchial inflammation are characteristic hallmarks of cystic fibrosis (CF) lung disease. The free radicals generated can be deleterious for structure and function of many proteins. The goal of this study was to investigate the degree of oxidation of pulmonary epithelial lining fluid proteins. BAL fluid (BALF) from 55 children with CF and from 11 patients in a control group were investigated by dot-blot assay for content and by two-dimensional electrophoresis and Western blotting for the pattern of distribution of oxidized proteins. The highest level of oxidative stress, as assessed by the level of protein carbonyls, was found in patients with FEV1 < 80% of predicted or with highly elevated neutrophil counts. Compared to control subjects without lung disease, CF patients with normal lung function and CF patients with a normal neutrophil count in their BALF had significantly higher protein carbonyl levels. The extent of protein oxidation was directly related to the neutrophil granulocyte count and inversely to lung function. Our data support the hypothesis that oxidative damage of pulmonary proteins during chronic and excessive neutrophilic endobronchial inflammation may contribute to the decline of lung function in CF patients.
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Affiliation(s)
- Vitaliy Starosta
- Lung Research Group, Children's Hospital of Ludwig Maximilians University, Munich
| | - Ernst Rietschel
- Department of Pediatric Pneumology and Allergology, Childrens' Hospital University of Cologne, Cologne
| | - Karl Paul
- Department of Pediatric Pneumology and Immunology, Charité, Humboldt-University, Berlin
| | - Ulrich Baumann
- Department of Pediatric Pulmonology and Neonatology, Hannover Medical School, Hannover, Germany
| | - Matthias Griese
- Lung Research Group, Children's Hospital of Ludwig Maximilians University, Munich.
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