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Acute Pneumonia. MANDELL, DOUGLAS, AND BENNETT'S PRINCIPLES AND PRACTICE OF INFECTIOUS DISEASES 2015. [PMCID: PMC7151914 DOI: 10.1016/b978-1-4557-4801-3.00069-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Chen L, Guo S, Wu L, Hao C, Xu W, Zhang J. Effects of recombinant IL-17F intranasal inoculation againstStreptococcus pneumoniaeinfection in a murine model. Biotechnol Appl Biochem 2014; 62:393-400. [PMID: 25196250 DOI: 10.1002/bab.1286] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Accepted: 08/30/2014] [Indexed: 11/06/2022]
Affiliation(s)
- Ling Chen
- Department of Pediatrics; Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University; Shanghai 200233 People's Republic of China
| | - Sheng Guo
- Department of Pediatrics; Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University; Shanghai 200233 People's Republic of China
| | - Liangxia Wu
- Department of Pediatrics; Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University; Shanghai 200233 People's Republic of China
| | - Chunli Hao
- Department of Pediatrics; Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University; Shanghai 200233 People's Republic of China
| | - Wanting Xu
- Department of Pediatrics; Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University; Shanghai 200233 People's Republic of China
| | - Jianhua Zhang
- Department of Pediatrics; Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University; Shanghai 200233 People's Republic of China
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Mukherjee S, Weimer KE, Seok SC, Ray WC, Jayaprakash C, Vieland VJ, Swords WE, Das J. Host-to-host variation of ecological interactions in polymicrobial infections. Phys Biol 2014; 12:016003. [PMID: 25473880 DOI: 10.1088/1478-3975/12/1/016003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Host-to-host variability with respect to interactions between microorganisms and multicellular hosts are commonly observed in infection and in homeostasis. However, the majority of mechanistic models used to analyze host-microorganism relationships, as well as most of the ecological theories proposed to explain coevolution of hosts and microbes, are based on averages across a host population. By assuming that observed variations are random and independent, these models overlook the role of differences between hosts. Here, we analyze mechanisms underlying host-to-host variations of bacterial infection kinetics, using the well characterized experimental infection model of polymicrobial otitis media (OM) in chinchillas, in combination with population dynamic models and a maximum entropy (MaxEnt) based inference scheme. We find that the nature of the interactions between bacterial species critically regulates host-to-host variations in these interactions. Surprisingly, seemingly unrelated phenomena, such as the efficiency of individual bacterial species in utilizing nutrients for growth, and the microbe-specific host immune response, can become interdependent in a host population. The latter finding suggests a potential mechanism that could lead to selection of specific strains of bacterial species during the coevolution of the host immune response and the bacterial species.
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Affiliation(s)
- Sayak Mukherjee
- Battelle Center for Mathematical Medicine, The Research Institute at the Nationwide Children's Hospital and, The Ohio State University, 700 Children's Drive, Columbus, OH 43205, USA. Departments of Pediatrics, The Ohio State University, 700 Children's Drive, Columbus, OH 43205, USA
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Zhang YZ, Qie JY, Zhang QH. Incidence and mortality prognosis of dysnatremias in neurologic critically ill patients. Eur Neurol 2014; 73:29-36. [PMID: 25377050 DOI: 10.1159/000368353] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 09/14/2014] [Indexed: 11/19/2022]
Abstract
BACKGROUND Dysnatremia, which is associated with increased mortality in general intensive care units (ICU), has not been thoroughly studied in neurologic ICU (NICU). METHODS Prevalence of dysnatremia was retrospectively assessed. The multivariable binary logistic regression model was used to determine the influence of dysnatremia on mortality. RESULTS Of 519 patients, 106 (20.4%) were admitted with hyponatremia and 177 (34.10%) with hypernatremia. Hypernatremia was detected in 69 (13.29%) patients on admission to NICU and in 108 patients (20.81%) during the ICU stay. However, the incidence of dysnatremia did not differ across the neurological categories (p = 0.4690). ICU stay in patients with acquired hypernatremia (22.3 ± 25.35 days) was longer than those with admission hypernatremia (13.5 ± 12.8 days) or with consistent normonatremia (16.16 ± 20.06 days). The other indicators such as Acute Physiology and Chronic Health Evaluation II, Glasgow Coma Scale score, urinary catheterization, and incidence of pneumonia were also associated with the serum sodium concentrations. Hypernatremia both on admission and acquired in NICU could significantly differentiate between survivors and nonsurvivors (p = 0.002 and <0.0001). However, only NICU-acquired hypernatremia was the independent risk factor for mortality with high sensitivity (p = 0.000). CONCLUSIONS Dysnatremia is more common in NICU, whereas only acquired-hypernatremia was independently associated with outcome.
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Affiliation(s)
- Yun-Zhou Zhang
- Neurocritical Care Unit, Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, PR China
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Chen D, Yang Z, Chen X, Huang Y, Yin B, Guo F, Zhao H, Zhao T, Qu H, Huang J, Wu Y, Gu R. The effect of Lactobacillus rhamnosus hsryfm 1301 on the intestinal microbiota of a hyperlipidemic rat model. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2014; 14:386. [PMID: 25300818 PMCID: PMC4197344 DOI: 10.1186/1472-6882-14-386] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Accepted: 09/29/2014] [Indexed: 01/01/2023]
Abstract
BACKGROUND Growing evidence indicates that intestinal microbiota regulate our metabolism. Probiotics confer health benefits that may depend on their ability to affect the gut microbiota. The objective of this study was to examine the effect of supplementation with the probiotic strain, Lactobacillus rhamnosus hsryfm 1301, on the gut microbiota in a hyperlipidemic rat model, and to explore the associations between the gut microbiota and the serum lipids. METHODS The hyperlipidemic rat model was established by feeding rats a high-fat diet for 28 d. The rats' gut microbiota were analyzed using high-throughput sequencing before and after L. rhamnosus hsryfm 1301 supplementation or its fermented milk for 28 d. The serum lipids level was also tested. RESULTS The rats' primary gut microbiota were composed of Bacteroidetes, Firmicutes, Proteobacteria, Spirochaetes and Verrucomicrobia. The abundance and diversity of the gut microbiota generally decreased after feeding with a high-fat diet, with a significant decrease in the relative abundance of Bacteroidetes, but with an increase in that of Firmicutes (P < 0.05). Administration of L. rhamnosus hsryfm 1301 or its fermented milk for 28 d, could recover the Bacteroidetes and Verrucomicrobia abundance and could decrease the Firmicutes abundance, which was associated with a significant reduction in the serum lipids' level in the hyperlipidemic rats with high-fat diet induced. The abundance of 22 genera of gut bacteria was changed significantly after probiotic intervention for 28 d (P < 0.05). A positive correlation was observed between Ruminococcus spp. and serum triglycerides, Dorea spp. and serum cholesterol (TC) and low-density lipoprotein (LDL-C), and Enterococcus spp. and high-density lipoprotein. The Butyrivibrio spp. negatively correlated with TC and LDL-C. CONCLUSIONS Our results suggest that the lipid metabolism of hyperlipidemic rats was improved by regulating the gut microbiota with supplementation of L.rhamnosus hsryfm 1301 or its fermented milk for 28 d.
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Affiliation(s)
- Dawei Chen
- />College of Food Science and Technology, Yangzhou University, Yangzhou, 225127 Jiangsu Province China
- />Key Lab of Dairy Biotechnology and Safety Control, Yangzhou, 225127 Jiangsu Province China
| | - Zhenquan Yang
- />College of Food Science and Technology, Yangzhou University, Yangzhou, 225127 Jiangsu Province China
- />Key Lab of Dairy Biotechnology and Safety Control, Yangzhou, 225127 Jiangsu Province China
| | - Xia Chen
- />College of Food Science and Technology, Yangzhou University, Yangzhou, 225127 Jiangsu Province China
- />Key Lab of Dairy Biotechnology and Safety Control, Yangzhou, 225127 Jiangsu Province China
| | - Yujun Huang
- />College of Food Science and Technology, Yangzhou University, Yangzhou, 225127 Jiangsu Province China
- />Key Lab of Dairy Biotechnology and Safety Control, Yangzhou, 225127 Jiangsu Province China
| | - Boxing Yin
- />College of Food Science and Technology, Yangzhou University, Yangzhou, 225127 Jiangsu Province China
- />Key Lab of Dairy Biotechnology and Safety Control, Yangzhou, 225127 Jiangsu Province China
| | - Feixiang Guo
- />College of Food Science and Technology, Yangzhou University, Yangzhou, 225127 Jiangsu Province China
- />Key Lab of Dairy Biotechnology and Safety Control, Yangzhou, 225127 Jiangsu Province China
| | - Haiqing Zhao
- />College of Food Science and Technology, Yangzhou University, Yangzhou, 225127 Jiangsu Province China
- />Key Lab of Dairy Biotechnology and Safety Control, Yangzhou, 225127 Jiangsu Province China
| | - Tangyan Zhao
- />College of Food Science and Technology, Yangzhou University, Yangzhou, 225127 Jiangsu Province China
- />Key Lab of Dairy Biotechnology and Safety Control, Yangzhou, 225127 Jiangsu Province China
| | - Henxian Qu
- />College of Food Science and Technology, Yangzhou University, Yangzhou, 225127 Jiangsu Province China
- />Key Lab of Dairy Biotechnology and Safety Control, Yangzhou, 225127 Jiangsu Province China
| | - Jiadi Huang
- />Royal Dairy (Guangxi) Co., Ltd., Nanning, Guangxi 530007 China
| | - Yun Wu
- />Royal Dairy (Guangxi) Co., Ltd., Nanning, Guangxi 530007 China
| | - Ruixia Gu
- />College of Food Science and Technology, Yangzhou University, Yangzhou, 225127 Jiangsu Province China
- />Key Lab of Dairy Biotechnology and Safety Control, Yangzhou, 225127 Jiangsu Province China
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Abstract
AbstractBackground:Xylitol is a five-carbon sugar alcohol. Natural sources of xylitol include plums, strawberries and raspberries. Xylitol is commercially available in chewing gums, lozenges, syrups, nasal sprays, toothpastes, mouthwashes and other products in some countries. It has gained relative prominence in the past decade as a naturally occurring antibacterial agent.Objective:A review of contemporary literature was conducted to evaluate the efficacy of xylitol usage in ENT practice.Method:The English-language literature was searched using the following terms: xylitol, otitis media, nasal, sinusitis, dental caries and preventive therapy. The articles identified were included in this review.Results:Xylitol has no antibacterial properties of its own; rather, it appears to enhance the body's own innate immunity. Xylitol has anti-adhesive effects on micro-organisms like Streptococcus pneumoniae and Streptococcus mutans, inhibiting their growth. Xylitol has already been used for preventing otitis media, rhinosinusitis and dental caries. The worldwide spread of drug-resistant strains of pneumococci substantiates the need for new approaches to prevent ENT-related infectious diseases.Conclusion:Xylitol may be a promising agent for this purpose in ENT practice, but further experimental and clinical studies are required.
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Henderson AG, Ehre C, Button B, Abdullah LH, Cai LH, Leigh MW, DeMaria GC, Matsui H, Donaldson SH, Davis CW, Sheehan JK, Boucher RC, Kesimer M. Cystic fibrosis airway secretions exhibit mucin hyperconcentration and increased osmotic pressure. J Clin Invest 2014; 124:3047-60. [PMID: 24892808 DOI: 10.1172/jci73469] [Citation(s) in RCA: 245] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The pathogenesis of mucoinfective lung disease in cystic fibrosis (CF) patients likely involves poor mucus clearance. A recent model of mucus clearance predicts that mucus flow depends on the relative mucin concentration of the mucus layer compared with that of the periciliary layer; however, mucin concentrations have been difficult to measure in CF secretions. Here, we have shown that the concentration of mucin in CF sputum is low when measured by immunologically based techniques, and mass spectrometric analyses of CF mucins revealed mucin cleavage at antibody recognition sites. Using physical size exclusion chromatography/differential refractometry (SEC/dRI) techniques, we determined that mucin concentrations in CF secretions were higher than those in normal secretions. Measurements of partial osmotic pressures revealed that the partial osmotic pressure of CF sputum and the retained mucus in excised CF lungs were substantially greater than the partial osmotic pressure of normal secretions. Our data reveal that mucin concentration cannot be accurately measured immunologically in proteolytically active CF secretions; mucins are hyperconcentrated in CF secretions; and CF secretion osmotic pressures predict mucus layer-dependent osmotic compression of the periciliary liquid layer in CF lungs. Consequently, mucin hypersecretion likely produces mucus stasis, which contributes to key infectious and inflammatory components of CF lung disease.
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The lack of specificity of tracheal aspirates in the diagnosis of pulmonary infection in intubated children. Pediatr Crit Care Med 2014; 15:299-305. [PMID: 24614608 DOI: 10.1097/pcc.0000000000000106] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVES Ventilator-associated pneumonia is the first or second most commonly diagnosed nosocomial infection in the PICU. Centers for Disease Control diagnostic criteria include clinical signs or symptoms in conjunction with a "positive" tracheal aspirate, defined as more than 10 colony-forming units/mL of bacteria on quantitative culture and/or more than 25 polymorphonuclear neutrophils per low-power field on Gram stain. We hypothesized that tracheal aspirate cultures and Gram stains would not correlate with clinical signs and symptoms and would therefore not distinguish between colonization and infection. DESIGN Prospective observational study. SETTING PICU in an academic tertiary care center. PATIENTS Children intubated more than 48 hours. INTERVENTIONS Sequential tracheal aspirate quantitative cultures and Gram stains in conjunction with daily collection of concordant clinical signs and symptoms. MEASUREMENTS AND MAIN RESULTS Time since intubation correlated strongly (p < 0.001) with the proportion of positive (> 10 colony-forming units/mL) tracheal aspirate quantitative cultures, but Centers for Disease Control-defined clinical signs or symptoms of ventilator-associated pneumonia, either singly or in combination, did not. Use of in-line suction catheters versus new, sterile catheters to obtain tracheal aspirates was associated with significantly greater proportion of positive tracheal aspirate bacterial cultures (p < 0.001). Most subjects had more than 25 polymorphonuclear neutrophils per low-power field on Gram stain; polymorphonuclear neutrophils on Gram stain correlated with positive bacterial culture (p = 0.04). Seventy-seven percent of the bacterial isolates detected in positive quantitative cultures were "pathogens." Antibiotic use at the time tracheal aspirates were obtained was associated with a lower frequency of positive quantitative cultures only with antibiotic regimens that included cefepime. CONCLUSIONS Positive bacterial cultures of tracheal aspirates increase rapidly after intubation and usually include bacteria considered to be pathogens. Tracheal aspirate cultures and Gram stains do not appear to distinguish between infection and colonization. Antibiotic regimens that include cefepime decrease the frequency of positive cultures, but the significance of this is unclear.
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Ginsburg I, Koren E. Are cationic antimicrobial peptides also ‘double-edged swords’? Expert Rev Anti Infect Ther 2014; 6:453-62. [DOI: 10.1586/14787210.6.4.453] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Ganesan S, Comstock AT, Sajjan US. Barrier function of airway tract epithelium. Tissue Barriers 2013; 1:e24997. [PMID: 24665407 PMCID: PMC3783221 DOI: 10.4161/tisb.24997] [Citation(s) in RCA: 212] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 05/07/2013] [Accepted: 05/09/2013] [Indexed: 12/20/2022] Open
Abstract
Airway epithelium contributes significantly to the barrier function of airway tract. Mucociliary escalator, intercellular apical junctional complexes which regulate paracellular permeability and antimicrobial peptides secreted by the airway epithelial cells are the three primary components of barrier function of airway tract. These three components act cooperatively to clear inhaled pathogens, allergens and particulate matter without inducing inflammation and maintain tissue homeostasis. Therefore impairment of one or more of these essential components of barrier function may increase susceptibility to infection and promote exaggerated and prolonged innate immune responses to environmental factors including allergens and pathogens resulting in chronic inflammation. Here we review the regulation of components of barrier function with respect to chronic airways diseases.
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Affiliation(s)
- Shyamala Ganesan
- Department of Pediatrics and Communicable Diseases; University of Michigan; Ann Arbor, MI USA
| | - Adam T Comstock
- Department of Pediatrics and Communicable Diseases; University of Michigan; Ann Arbor, MI USA
| | - Uma S Sajjan
- Department of Pediatrics and Communicable Diseases; University of Michigan; Ann Arbor, MI USA
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Borcherding JA, Chen H, Caraballo JC, Baltrusaitis J, Pezzulo AA, Zabner J, Grassian VH, Comellas AP. Coal fly ash impairs airway antimicrobial peptides and increases bacterial growth. PLoS One 2013; 8:e57673. [PMID: 23469047 PMCID: PMC3585163 DOI: 10.1371/journal.pone.0057673] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Accepted: 01/24/2013] [Indexed: 12/22/2022] Open
Abstract
Air pollution is a risk factor for respiratory infections, and one of its main components is particulate matter (PM), which is comprised of a number of particles that contain iron, such as coal fly ash (CFA). Since free iron concentrations are extremely low in airway surface liquid (ASL), we hypothesize that CFA impairs antimicrobial peptides (AMP) function and can be a source of iron to bacteria. We tested this hypothesis in vivo by instilling mice with Pseudomonas aeruginosa (PA01) and CFA and determine the percentage of bacterial clearance. In addition, we tested bacterial clearance in cell culture by exposing primary human airway epithelial cells to PA01 and CFA and determining the AMP activity and bacterial growth in vitro. We report that CFA is a bioavailable source of iron for bacteria. We show that CFA interferes with bacterial clearance in vivo and in primary human airway epithelial cultures. Also, we demonstrate that CFA inhibits AMP activity in vitro, which we propose as a mechanism of our cell culture and in vivo results. Furthermore, PA01 uses CFA as an iron source with a direct correlation between CFA iron dissolution and bacterial growth. CFA concentrations used are very relevant to human daily exposures, thus posing a potential public health risk for susceptible subjects. Although CFA provides a source of bioavailable iron for bacteria, not all CFA particles have the same biological effects, and their propensity for iron dissolution is an important factor. CFA impairs lung innate immune mechanisms of bacterial clearance, specifically AMP activity. We expect that identifying the PM mechanisms of respiratory infections will translate into public health policies aimed at controlling, not only concentration of PM exposure, but physicochemical characteristics that will potentially cause respiratory infections in susceptible individuals and populations.
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Affiliation(s)
- Jennifer A. Borcherding
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Haihan Chen
- Department of Chemical and Biochemical Engineering, Iowa City, Iowa, United States of America
| | - Juan C. Caraballo
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Jonas Baltrusaitis
- Central Microscopy Research Facility, University of Iowa, Iowa City, Iowa, United States of America
| | - Alejandro A. Pezzulo
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Joseph Zabner
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Vicki H. Grassian
- Department of Chemistry, University of Iowa, Iowa City, Iowa, United States of America
| | - Alejandro P. Comellas
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
- * E-mail:
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Zecconi A, Scali F. Staphylococcus aureus virulence factors in evasion from innate immune defenses in human and animal diseases. Immunol Lett 2013; 150:12-22. [PMID: 23376548 DOI: 10.1016/j.imlet.2013.01.004] [Citation(s) in RCA: 149] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 12/09/2012] [Accepted: 01/08/2013] [Indexed: 01/04/2023]
Abstract
In the last decades, Staphylococcus aureus acquired a dramatic relevance in human and veterinary medicine for different reasons, one of them represented by the increasing prevalence of antibiotic resistant strains. However, antibiotic resistance is not the only weapon in the arsenal of S. aureus. Indeed, these bacteria have plenty of virulence factors, including a vast ability to evade host immune defenses. The innate immune system represents the first line of defense against invading pathogens. This system consists of three major effector mechanisms: antimicrobial peptides and enzymes, the complement system and phagocytes. In this review, we focused on S. aureus virulence factors involved in the immune evasion in the first phases of infection: TLR recognition avoidance, adhesins affecting immune response and resistance to host defenses peptides and polypeptides. Studies of innate immune defenses and their role against S. aureus are important in human and veterinary medicine given the problems related to S. aureus antimicrobial resistance. Moreover, due to the pathogen ability to manipulate the immune response, these data are needed to develop efficacious vaccines or molecules against S. aureus.
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Affiliation(s)
- Alfonso Zecconi
- Università degli Studi di Milano, Dip. Scienze Veterinarie e Sanità Pubblica, Via Celoria 10, 20133 Milano, Italy.
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63
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Park SI, Yoe SM. Overexpression and purification of recombinant lysozyme fromAgrius convolvuliexpressed as inclusion body inEscherichia coli. Anim Cells Syst (Seoul) 2012. [DOI: 10.1080/19768354.2012.706638] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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Wen S, Cao G, Bao T, Cheng L, Li H, Du C, Tu Y, Li Q, Jian R, Zhao P, Wuriliga. Modulation of ovine SBD-1 expression by 17beta-estradiol in ovine oviduct epithelial cells. BMC Vet Res 2012; 8:143. [PMID: 22920556 PMCID: PMC3487956 DOI: 10.1186/1746-6148-8-143] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Accepted: 08/10/2012] [Indexed: 12/02/2022] Open
Abstract
Background Mucosal epithelia, including those of the oviduct, secrete antimicrobial innate immune molecules (AIIMS). These have bactericidal/bacteriostatic functions against a variety of pathogens. Among the AIIMs, sheep β-defensin-1 (SBD-1) is one of the most potent. Even though the SBD-1 is an important AIIM and it is regulated closely by estrogenic hormone, the regulation mechanism of 17β-estradiol has not been clearly established. We investigated the effects of E2 and agonist or inhibitor on ovine oviduct epithelial cells in regard to SBD-1 expression using reverse transcription quantitative PCR (RT-qPCR). In addition, three different pathways were inhibited separately or simultaneously to confirm the effect of different inhibitors in the regulation mechanism. Results 17beta-estradiol (E2) induced release of SBD-1 in ovine oviduct epithelial cells. SBD-1 expression was mediated through G-protein-coupled receptor 30 (GPR30) and Estrogen Receptors (ERs) activation in ovine oviduct epithelial cell. Inhibition of gene expression of protein kinase A (PKA), protein kinase C (PKC), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) led to a decreased SBD-1 expression. Conclusions Taken together, E2-induced up-regulation of SBD-1 expressions were GPR30-dependent during prophase and ERs-dependent during later-stage in ovine oviduct epithelial cells, and we assume that the effect was completed by the PKA, PKC, and NF-κB pathways simultaneous.
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Affiliation(s)
- Shiyong Wen
- College of Veterinary, Inner Mongolia Agricultural University, Huhhot, 010018, People's Republic of China
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65
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Nathe KE, Mancuso CJ, Parad R, Van Marter LJ, Martin CR, Stoler-Barak L, Philbin VJ, Phillips MF, Palmer CD, Levy O. Innate immune activation in neonatal tracheal aspirates suggests endotoxin-driven inflammation. Pediatr Res 2012; 72:203-11. [PMID: 22580716 PMCID: PMC3406551 DOI: 10.1038/pr.2012.61] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Tracheal aspirates (TAs) from critically ill neonates accumulate bacterial endotoxin and demonstrate mobilization of endotoxin-binding proteins, but the potential bioactivity of endotoxin in TAs is unknown. We characterized innate immune activation in TAs of mechanically ventilated neonates. METHODS Innate immune activation in TAs of mechanically ventilated neonates was characterized using a targeted 84-gene quantitative real-time (qRT) PCR array. Protein expression of cytokines was confirmed by multiplex assay. Expression and localization of the endotoxin-inducible antimicrobial protein Calgranulin C (S100A12) was assessed by flow cytometry. Endotoxin levels were measured in TA supernatants using the Limulus amoebocyte lysate assay. RESULTS Analyses by qRT-PCR demonstrated expression of pattern recognition receptors, Toll-like receptor-nuclear factor κB and inflammasome pathways, cytokines/chemokines and their receptors, and anti-infective proteins in TA cells. Endotoxin positivity increased with postnatal age. As compared with endotoxin-negative TAs, endotoxin-positive TAs demonstrated significantly greater tumor necrosis factor (TNF), interleukin (IL)-6, IL-10, and serpin peptidase inhibitor, clade E, member 1 (SERPINE1) mRNA, and IL-10, TNF, and IL-1β protein. Expression of S100A12 protein was localized to TA neutrophils. CONCLUSION Correlation of endotoxin with TA inflammatory responses suggests endotoxin bioactivity and the possibility that endotoxin antagonists could mitigate pulmonary inflammation and its sequelae in this vulnerable population.
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Affiliation(s)
- Katheryn E. Nathe
- Department of Medicine, Children's Hospital Boston, Boston, Massachusetts,Department of Newborn Medicine, Brigham and Women's Hospital, Boston, Massachusetts,Department of Pediatrics, Massachusetts General Hospital for Children at North Shore Medical Center, Salem, Massachusetts,Harvard Medical School, Boston, Massachusetts
| | - Christy J. Mancuso
- Department of Medicine, Children's Hospital Boston, Boston, Massachusetts
| | - Richard Parad
- Department of Medicine, Children's Hospital Boston, Boston, Massachusetts,Department of Newborn Medicine, Brigham and Women's Hospital, Boston, Massachusetts,Harvard Medical School, Boston, Massachusetts
| | - Linda J. Van Marter
- Department of Medicine, Children's Hospital Boston, Boston, Massachusetts,Department of Newborn Medicine, Brigham and Women's Hospital, Boston, Massachusetts,Harvard Medical School, Boston, Massachusetts
| | - Camilia R. Martin
- Harvard Medical School, Boston, Massachusetts,Department of Neonatology Beth Israel Deaconess Medical Center, Boston, Massachusetts
| | - Liat Stoler-Barak
- Department of Medicine, Children's Hospital Boston, Boston, Massachusetts
| | - Victoria J. Philbin
- Department of Medicine, Children's Hospital Boston, Boston, Massachusetts,Harvard Medical School, Boston, Massachusetts
| | - Michele F. Phillips
- Department of Newborn Medicine, Brigham and Women's Hospital, Boston, Massachusetts
| | - Christine D. Palmer
- Department of Medicine, Children's Hospital Boston, Boston, Massachusetts,Harvard Medical School, Boston, Massachusetts
| | - Ofer Levy
- Department of Medicine, Children's Hospital Boston, Boston, Massachusetts,Harvard Medical School, Boston, Massachusetts,()
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Yang IV, Luna LG, Cotter J, Talbert J, Leach SM, Kidd R, Turner J, Kummer N, Kervitsky D, Brown KK, Boon K, Schwarz MI, Schwartz DA, Steele MP. The peripheral blood transcriptome identifies the presence and extent of disease in idiopathic pulmonary fibrosis. PLoS One 2012; 7:e37708. [PMID: 22761659 PMCID: PMC3382229 DOI: 10.1371/journal.pone.0037708] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Accepted: 04/23/2012] [Indexed: 01/05/2023] Open
Abstract
Rationale Peripheral blood biomarkers are needed to identify and determine the extent of idiopathic pulmonary fibrosis (IPF). Current physiologic and radiographic prognostic indicators diagnose IPF too late in the course of disease. We hypothesize that peripheral blood biomarkers will identify disease in its early stages, and facilitate monitoring for disease progression. Methods Gene expression profiles of peripheral blood RNA from 130 IPF patients were collected on Agilent microarrays. Significance analysis of microarrays (SAM) with a false discovery rate (FDR) of 1% was utilized to identify genes that were differentially-expressed in samples categorized based on percent predicted DLCO and FVC. Main Measurements and Results At 1% FDR, 1428 genes were differentially-expressed in mild IPF (DLCO >65%) compared to controls and 2790 transcripts were differentially- expressed in severe IPF (DLCO >35%) compared to controls. When categorized by percent predicted DLCO, SAM demonstrated 13 differentially-expressed transcripts between mild and severe IPF (< 5% FDR). These include CAMP, CEACAM6, CTSG, DEFA3 and A4, OLFM4, HLTF, PACSIN1, GABBR1, IGHM, and 3 unknown genes. Principal component analysis (PCA) was performed to determine outliers based on severity of disease, and demonstrated 1 mild case to be clinically misclassified as a severe case of IPF. No differentially-expressed transcripts were identified between mild and severe IPF when categorized by percent predicted FVC. Conclusions These results demonstrate that the peripheral blood transcriptome has the potential to distinguish normal individuals from patients with IPF, as well as extent of disease when samples were classified by percent predicted DLCO, but not FVC.
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Affiliation(s)
- Ivana V. Yang
- Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado, United States of America
- Department of Medicine; University of Colorado, Denver, Aurora, Colorado, United States of America
| | - Leah G. Luna
- Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado, United States of America
| | - Jennifer Cotter
- Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado, United States of America
| | - Janet Talbert
- Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado, United States of America
| | - Sonia M. Leach
- Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado, United States of America
| | - Raven Kidd
- Pulmonary, Allergy, Critical Care Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Julia Turner
- Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado, United States of America
| | - Nathan Kummer
- Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado, United States of America
| | - Dolly Kervitsky
- Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado, United States of America
- Interstitial Lung Disease Laboratory, National Jewish Health, Denver, Colorado, United States of America
| | - Kevin K. Brown
- Interstitial Lung Disease Laboratory, National Jewish Health, Denver, Colorado, United States of America
| | - Kathy Boon
- Excerpta Medica, Amsterdam, The Netherlands
| | - Marvin I. Schwarz
- Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado, United States of America
- Department of Medicine; University of Colorado, Denver, Aurora, Colorado, United States of America
| | - David A. Schwartz
- Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado, United States of America
- Department of Medicine; University of Colorado, Denver, Aurora, Colorado, United States of America
| | - Mark P. Steele
- Excerpta Medica, Amsterdam, The Netherlands
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
- * E-mail:
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Alexander DB, Iigo M, Yamauchi K, Suzui M, Tsuda H. Lactoferrin: an alternative view of its role in human biological fluids. Biochem Cell Biol 2012; 90:279-306. [PMID: 22553915 DOI: 10.1139/o2012-013] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Lactoferrin is a major component of biologically important mucosal fluids and of the specific granules of neutrophils. Understanding its biological function is essential for understanding neutrophil- and mucosal-mediated immunity. In this review, we reevaluate the in vivo functions of human lactoferrin (hLF) emphasizing in vivo studies and in vitro studies performed in biologically relevant fluids. We discuss the evidence in the literature that supports (or does not support) proposed roles for hLF in mucosal immunity and in neutrophil function. We argue that the current literature supports a microbiostatic role, but not a microbicidal role, for hLF in vivo. The literature also supports a role for hLF in inhibiting colonization and infection of epithelial surfaces by microorganisms and in protecting tissues from neutrophil-mediated damage. Using this information, we briefly discuss hLF in the context of the complex biological fluids in which it is found.
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Affiliation(s)
- David B Alexander
- Laboratory of Nanotoxicology Project, Nagoya City University, 3-1 Tanabedohri, Mizuho-ku, Nagoya 467-8603, Japan.
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Deletion of aquaporin 5 aggravates acute lung injury induced by Pseudomonas aeruginosa. ACTA ACUST UNITED AC 2011; 71:1305-11. [PMID: 21502879 DOI: 10.1097/ta.0b013e3182128528] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
BACKGROUND Aquaporin (AQP) is a membrane protein that facilitates osmotic water transport. Aquaporin 5 (AQP5) expresses at type I alveolar epithelia of apical membrane that confers high osmotic water permeability. Osmosis or stretch challenge in alveoli significantly up-regulates AQP5 expression, which suggests that AQP5 may play a role in the maintenance of epithelia barrier function. Pseudomonas aeruginosa (PA), a leading gram-negative bacterial frequently isolated from ventilation-associated pneumonia patients, disrupts alveolar and airway epithelial cells and subsequently leads to blood dissemination. In this study, we hypothesized that AQP5 might be protective in acute lung injury induced by PA, and deletion of AQP5 might lead to aggravated lung injury. METHODS Lung injury model was induced by intratracheal instillation of PA (1 × 10(6) colony-forming unit) in wild-type and AQP5 knockout mice, 2 hours and 6 hours later, blood and lung lysate were cultured to detect blood dissemination, bronchoalveolar lavage fluid and lung tissue were collected for histology analysis. Lung injury assessment, wet/dry weight ratio, protein leakage, and Evan's blue dye extravasation were evaluated for pulmonary barrier function. RESULTS AQP5 deficiency led to increased bacterial blood dissemination and aggravated lung injury during PA infection, and AQP5 deletion also reduced mucin production in lung. Moreover, AQP5 deficiency showed declined activation of mitogen-activated protein kinase and nuclear factor-kappa B pathways in lungs before and after PA infection. CONCLUSION Our data demonstrated that AQP5 plays a protective role in the maintenance of pulmonary barrier function against PA infection.
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El-Sherbiny IM, Smyth HDC. Controlled release pulmonary administration of curcumin using swellable biocompatible microparticles. Mol Pharm 2011; 9:269-80. [PMID: 22136259 DOI: 10.1021/mp200351y] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This study involves a promising approach to achieve sustained pulmonary drug delivery. Dry powder particulate carriers were engineered to allow simultaneous aerosol lung delivery, evasion of macrophage uptake, and sustained drug release through a controlled polymeric architecture. Chitosan grafted with PEG was synthesized and characterized (FTIR, EA, DSC and 2D-XRD). Then, a series of respirable amphiphilic hydrogel microparticles were developed via spray drying of curcumin-loaded PLGA nanoparticles with chitosan-grafted-PEG or chitosan. The nanoparticles and microparticles were fully characterized using an array of physicochemical analytical methods including particle size, surface morphology, dynamic swelling, density, moisture content and biodegradation rates. The PLGA nanoparticles and the hydrogel microspheres encapsulating the curcumin-loaded PLGA nanoparticles showed average size of 221-243 nm and 3.1-3.9 μm, respectively. The developed carriers attained high swelling within a few minutes and showed low moisture content as dry powders (0.9-1.8%), desirable biodegradation rates, high drug loading (up to 97%), and good sustained release. An aerosolization study was conducted using a next generation impactor, and promising aerosolization characteristics were shown. In vitro macrophage uptake studies, cytotoxicity and in vitro TNF-α assays were performed for the investigated particles. These assays revealed promising biointeractions for the respirable/swellable nano-micro particles developed in this study as potential carriers for sustained pulmonary drug delivery.
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Affiliation(s)
- Ibrahim M El-Sherbiny
- Polymer Laboratory, Chemistry Department, Faculty of Science, Mansoura University, ET-35516 Mansoura, Egypt
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70
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Shin DM, Jo EK. Antimicrobial Peptides in Innate Immunity against Mycobacteria. Immune Netw 2011; 11:245-52. [PMID: 22194707 PMCID: PMC3242998 DOI: 10.4110/in.2011.11.5.245] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Revised: 09/16/2011] [Accepted: 09/23/2011] [Indexed: 01/14/2023] Open
Abstract
Antimicrobial peptides/proteins are ancient and naturallyoccurring antibiotics in innate immune responses in a variety of organisms. Additionally, these peptides have been recognized as important signaling molecules in regulation of both innate and adaptive immunity. During mycobacterial infection, antimicrobial peptides including cathelicidin, defensin, and hepcidin have antimicrobial activities against mycobacteria, making them promising candidates for future drug development. Additionally, antimicrobial peptides act as immunomodulators in infectious and inflammatory conditions. Multiple crucial functions of cathelicidins in antimycobacterial immune defense have been characterized not only in terms of direct killing of mycobacteria but also as innate immune regulators, i.e., in secretion of cytokines and chemokines, and mediating autophagy activation. Defensin families are also important during mycobacterial infection and contribute to antimycobacterial defense and inhibition of mycobacterial growth both in vitro and in vivo. Hepcidin, although its role in mycobacterial infection has not yet been characterized, exerts antimycobacterial effects in activated macrophages. The present review focuses on recent efforts to elucidate the roles of host defense peptides in innate immunity to mycobacteria.
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Affiliation(s)
- Dong-Min Shin
- Department of Microbiology and Infection Signaling Network Research Center, Chungnam National University, School of Medicine, Daejeon 301-747, Korea
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Reilly C, Cervenka T, Hertz MI, Becker T, Wendt CH. Human neutrophil peptide in lung chronic allograft dysfunction. Biomarkers 2011; 16:663-9. [PMID: 21988113 DOI: 10.3109/1354750x.2011.623789] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CONTEXT Our previous case-control study identified human neutrophil peptide (HNP) as a potential biomarker for bronchiolitis obliterans syndrome (BOS) in lung transplant recipients. OBJECTIVE To prospectively validate HNP as a biomarker for BOS. MATERIALS AND METHODS HNP was measured by ELISA in bronchoalveolar lavage (BAL) fluid in lung transplant recipients. RESULTS The first HNP measurement after reaching baseline pulmonary function was predictive of developing BOS ≥2 (p = 0.0419). HNP remained elevated in those that developed BOS. The effect of potential confounders did not significantly impact BOS-free survival time. CONCLUSION HNP levels are elevated early and persistently in those that develop BOS.
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Affiliation(s)
- Cavan Reilly
- Department of Biostatistics, University of Minnesota, Minneapolis, MN, USA
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Foreman A, Jervis-Bardy J, Wormald PJ. Do biofilms contribute to the initiation and recalcitrance of chronic rhinosinusitis? Laryngoscope 2011; 121:1085-91. [PMID: 21520128 DOI: 10.1002/lary.21438] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Chronic rhinosinusitis is a common disease whose underlying aetiopathogenesis has not been completely understood. Amongst a range of other potential environmental triggers in this disease, a role has recently been proposed for bacterial biofilms. Adopting the biofilm paradigm to explain the initiation and maintenance of this disease may help to clarify previous inconsistencies in this disease that have resulted in the role of bacteria being questioned. Of particular interest is the association of bacterial biofilms with recalcitrant disease states. Over the last five years, research has progressed rapidly since biofilms were first identified on the surface of diseased sinonasal mucosa. Their presence there has now been associated with more severe disease that is often recalcitrant to current management paradigms. Technological advances are allowing accurate characterization of the bacterial and fungal species within these biofilms, which would appear to be an important step in improving our understanding of how these bacterial communities might interact with the host to cause disease. This is an unanswered, yet highly important, question in this field of research that will undoubtedly be an area of investigation in the near future. As the body of evidence suggesting biofilms may be involved in this disease grows, research interest has switched to the development of antibiofilm therapies. Given the unique properties of bacteria existing in this form, biofilm eradication strategies will need to incorporate novel medical therapies into established surgical practices as we attempt to improve the outcomes of our most difficult patients.
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Affiliation(s)
- Andrew Foreman
- Department of Surgery-Otorhinolaryngology, Head and Neck Surgery, University of Adelaide and Flinders University, Adelaide, Australia
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Gemcitabine-loaded chitosan microspheres. Characterization and biological in vitro evaluation. Biomed Microdevices 2011; 13:799-807. [DOI: 10.1007/s10544-011-9550-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Shelburne CP, Abraham SN. The mast cell in innate and adaptive immunity. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 716:162-85. [PMID: 21713657 DOI: 10.1007/978-1-4419-9533-9_10] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Mast cells (MCs) were once considered only as effector cells in pathogenic IgE- and IgG-mediated responses such as allergy. However, developments over the last 15 years have suggested that MCs have evolved in vertebrates as beneficial effector cells that are involved in the very first inflammatory responses generated during infection. This pro-inflammatory environment has been demonstrated to be important for initiating innate responses in many different models of infection and more recently, in the development of adaptive immunity as well. Interestingly this latter finding has led to the discovery that small MC-activating compounds can behave as adjuvants in vaccine formulations. Thus, our continued understanding of the MC in the context of infectious disease is likely to not only expand our scope of the MC in the normal processes of immunity, but provide new therapeutic targets to combat disease.
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Benakanakere MR, Zhao J, Galicia JC, Martin M, Kinane DF. Sphingosine kinase-1 is required for toll mediated beta-defensin 2 induction in human oral keratinocytes. PLoS One 2010; 5:e11512. [PMID: 20634980 PMCID: PMC2901390 DOI: 10.1371/journal.pone.0011512] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Accepted: 06/18/2010] [Indexed: 12/23/2022] Open
Abstract
Background Host defense against invading pathogens is triggered by various receptors including toll-like receptors (TLRs). Activation of TLRs is a pivotal step in the initiation of innate, inflammatory, and antimicrobial defense mechanisms. Human β-defensin 2 (HBD-2) is a cationic antimicrobial peptide secreted upon Gram-negative bacterial perturbation in many cells. Stimulation of various TLRs has been shown to induce HBD-2 in oral keratinocytes, yet the underlying cellular mechanisms of this induction are poorly understood. Principal Findings Here we demonstrate that HBD-2 induction is mediated by the Sphingosine kinase-1 (Sphk-1) and augmented by the inhibition of Glycogen Synthase Kinase-3β (GSK-3β) via the Phosphoinositide 3-kinase (PI3K) dependent pathway. HBD-2 secretion was dose dependently inhibited by a pharmacological inhibitor of Sphk-1. Interestingly, inhibition of GSK-3β by SB 216763 or by RNA interference, augmented HBD-2 induction. Overexpression of Sphk-1 with concomitant inhibition of GSK-3β enhanced the induction of β-defensin-2 in oral keratinocytes. Ectopic expression of constitutively active GSK-3β (S9A) abrogated HBD-2 whereas kinase inactive GSK-3β (R85A) induced higher amounts of HBD-2. Conclusions/Significance These data implicate Sphk-1 in HBD-2 regulation in oral keratinocytes which also involves the activation of PI3K, AKT, GSK-3β and ERK 1/2. Thus we reveal the intricate relationship and pathways of toll-signaling molecules regulating HBD-2 which may have therapeutic potential.
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Affiliation(s)
- Manjunatha R. Benakanakere
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Jiawei Zhao
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Johnah C. Galicia
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Michael Martin
- School of Dentistry, Oral Health and Systemic Disease Center, University of Louisville, Louisville, Kentucky, United States of America
| | - Denis F. Kinane
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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Klebsiella pneumoniae capsule polysaccharide impedes the expression of beta-defensins by airway epithelial cells. Infect Immun 2009; 78:1135-46. [PMID: 20008534 DOI: 10.1128/iai.00940-09] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Human beta-defensins (hBDs) contribute to the protection of the respiratory tract against pathogens. It is reasonable to postulate that pathogens have developed countermeasures to resist them. Klebsiella pneumoniae capsule polysaccharide (CPS), but not the lipopolysaccharide O antigen, mediated resistance against hBD1 and hBD2. hBD3 was the most potent hBD against Klebsiella. We investigated the possibility that as a strategy for survival in the lung, K. pneumoniae may not activate the expression of hBDs. Infection of A549 and normal human bronchial cells with 52145-Deltawca(K2), a CPS mutant, increased the expression of hBD2 and hBD3. Neither the wild type nor the lipopolysaccharide O antigen mutant increased the expression of hBDs. In vivo, 52145-Deltawca(K2) induced higher levels of mBD4 and mBD14, possible mouse orthologues of hBD2 and hBD3, respectively, than the wild type. 52145-Deltawca(K2)-dependent upregulation of hBD2 occurred via NF-kappaB and mitogen-activated protein kinases (MAPKs) p44/42, Jun N-terminal protein kinase (JNK)-dependent pathways. The increase in hBD3 expression was dependent on the MAPK JNK. 52145-Deltawca(K2) engaged Toll-like receptors 2 and 4 (TLR2 and TLR4) to activate hBD2, whereas hBD3 expression was dependent on NOD1. K. pneumoniae induced the expression of CYLD and MKP-1, which act as negative regulators for 52145-Deltawca(K2)-induced expression of hBDs. Bacterial engagement of pattern recognition receptors induced CYLD and MKP-1, which may initiate the attenuation of proinflammatory pathways. The results of this study indicate that K. pneumoniae CPS not only protects the pathogen from the bactericidal action of defensins but also impedes their expression. These features of K. pneumoniae CPS may facilitate pathogen survival in the hostile environment of the lung.
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Benincasa M, Mattiuzzo M, Herasimenka Y, Cescutti P, Rizzo R, Gennaro R. Activity of antimicrobial peptides in the presence of polysaccharides produced by pulmonary pathogens. J Pept Sci 2009; 15:595-600. [PMID: 19466693 DOI: 10.1002/psc.1142] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Antimicrobial peptides (AMPs) are secreted in the airway and contribute to initial defence against inhaled pathogens. Infections of the respiratory tract are a major cause of morbidity and mortality in preterm newborns and in patients with cystic fibrosis (CF). In this latter group, the state of chronic lung infection is due to the ability of bacteria to grow as mucoid biofilm, a condition characterised by overproduction and release of polysaccharides (PSs). In this study, we investigate the effect of PSs produced by lung pathogens such as Pseudomonas aeruginosa, Klebsiella pneumoniae and members of the Burkholderia cepacia complex on the antibacterial activity of structurally different peptides. The AMPs tested in this study include the cathelicidin LL-37 and the beta-defensin hBD-3 from humans, both released at the alveolar level, as well as peptides from other mammals, i.e. SMAP-29, PG-1 and Bac7(1-35). Susceptibility assays, time killing and membrane permeabilization kinetics experiments were carried out to establish whether PSs produced by lung pathogens may be involved in the poor defence reaction of infected lungs and thus explain infection persistence. All the PSs investigated inhibited, albeit to a different extent, the antibacterial activity of the peptides tested, suggesting that their presence in the lungs of patients with CF may contribute to the decreased defence response of this district upon infection by PS-producing microorganisms. The results also show that inhibition of the antibacterial activity is not simply due to ionic interaction between the negatively charged PSs and the cationic AMPs, but it also involves other structural features of both interactors.
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Affiliation(s)
- M Benincasa
- Department of Life Sciences, University of Trieste, I-34127 Trieste, Italy
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Klebsiella pneumoniae AcrAB efflux pump contributes to antimicrobial resistance and virulence. Antimicrob Agents Chemother 2009; 54:177-83. [PMID: 19858254 DOI: 10.1128/aac.00715-09] [Citation(s) in RCA: 271] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Respiratory infections caused by Klebsiella pneumoniae are characterized by high rates of mortality and morbidity. Management of these infections is often difficult, due to the high frequency of strains that are resistant to multiple antimicrobial agents. Multidrug efflux pumps play a major role as a mechanism of antimicrobial resistance in Gram-negative pathogens. In the present study, we investigated the role of the K. pneumoniae AcrRAB operon in antimicrobial resistance and virulence by using isogenic knockouts deficient in the AcrB component and the AcrR repressor, both derived from the virulent strain 52145R. We demonstrated that the AcrB knockout was more susceptible, not only to quinolones, but also to other antimicrobial agents, including beta-lactams, than the wild-type strain and the AcrR knockout. We further showed that the AcrB knockout was more susceptible to antimicrobial agents present in human bronchoalveolar lavage fluid and to human antimicrobial peptides than the wild-type strain and the AcrR knockout. Finally, the AcrB knockout exhibited a reduced capacity to cause pneumonia in a murine model, in contrast to the wild-type strain. The results of this study suggest that, in addition to contributing to the multidrug resistance phenotype, the AcrAB efflux pump may represent a novel virulence factor required for K. pneumoniae to resist innate immune defense mechanisms of the lung, thus facilitating the onset of pneumonia.
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Efficacy and safety of normal saline instillation: a systematic review. Physiotherapy 2009; 95:241-50. [PMID: 19892088 DOI: 10.1016/j.physio.2009.06.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Accepted: 06/16/2009] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To investigate the efficacy and safety of the technique of instillation of normal saline prior to suction of airways in intubated patients. DATA SOURCES Databases searched included: MEDLINE, CINAHL, EMBASE, Cochrane Controlled Trials Register and Full text clinicians' health journals @ Ovid from the earliest time to March 2009. Citation tracking of relevant primary and review articles. REVIEW METHODS All randomised controlled trials, crossover trials, quasi- and full systematic reviews were screened. From 65 articles screened, 17 articles (two quasi-systematic reviews and 15 empirical studies) met the eligibility criteria and were included for data extraction. The outcomes in the reviewed studies included oxygenation, lung mechanics, sputum yield, dyspnoea, tube patency and ventilator-associated pneumonia. Effect sizes and 95% confidence intervals were calculated. RESULTS Studies were mainly of low methodological quality due to factors such as lack of assessor blinding and within-group-only statistics. Overall, there was a positive effect favouring the use of saline to increase sputum yield (d=0.50, 95% confidence interval 0.10 to 0.90). Due to heterogeneity of methodology, it was not possible to perform meta-analyses on haemodynamics, oxygenation, tube patency and ventilator-associated pneumonia. Overall, while a decrease was found in oxygen saturation measured by pulse oximetry (SpO(2)) following instillation of normal saline compared with no saline, this was of limited clinical significance. CONCLUSIONS The results of this review reflect the poor quality of available articles on instillation of normal saline prior to suction of artificial airways. There is little evidence of benefit but also minimal evidence of safety risks. Controlled trials of better quality and more clinically relevant outcomes need to be performed before this technique is either accepted or rejected.
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Durairaj L, Mohamad Z, Launspach JL, Ashare A, Choi JY, Rajagopal S, Doern GV, Zabner J. Patterns and density of early tracheal colonization in intensive care unit patients. J Crit Care 2009; 24:114-21. [PMID: 19272547 DOI: 10.1016/j.jcrc.2008.10.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2007] [Revised: 07/14/2008] [Accepted: 10/21/2008] [Indexed: 11/28/2022]
Abstract
OBJECTIVE The study aimed to describe the patterns and density of early tracheal colonization among intubated patients and to correlate colonization status with levels of antimicrobial peptides and inflammatory cytokines. DESIGN The was a prospective cohort study. SETTING The study was conducted in medical and cardiovascular intensive care units of a tertiary referral hospital. PATIENTS Seventy-four adult patients admitted between March 2003 and May 2006 were recruited for the study. INTERVENTIONS Tracheal aspirates were collected daily for the first 4 days of intubation using standardized, sterile technique and sent for quantitative culture and cytokines, lactoferrin and lysozyme measurements. MEASUREMENTS AND MAIN RESULTS The mean acute physiology and chronic health evaluation (APACHE II) score in this cohort was 24 +/- 7. Proportion of subjects colonized by any microorganism increased over the first 4 days of intubation (47%, 60%, 70%, 70%, P = .08), but density of colonization for bacteria or yeast did not change significantly. No known risk factors predicted tracheal colonization on day 1 of intubation. Several patterns of colonization were observed (persistent, transient, new colonization, and clearance of initial colonization).The most common organisms cultured were Candida albicans and coagulase-negative Staphylococcus. Levels of cytokines, lactoferrin, or lysozyme did not change over time and were not correlated with tracheal colonization status. Four subjects (6%) had ventilator-associated pneumonia. CONCLUSIONS The density of tracheal colonization did not change significantly over the first 4 days of intubation in medical intensive care unit patients. There was no correlation between tracheal colonization and the levels of antimicrobial peptides or cytokines. Several different patterns of colonization may have to be considered while planning interventions to reduce airway colonization.
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Affiliation(s)
- Lakshmi Durairaj
- Department of Medicine, University of Iowa Carver College of Medicine, Iowa City, IA 52242, USA.
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NATHE KATHERYNE, PARAD RICHARD, VAN MARTER LINDAJ, LUND CARAA, SUTER EUGÉNIEE, HERNANDEZ-DIAZ SONIA, BOUSH ELIZABETHBG, IKONOMU EVA, MOREY JOANN, ZEMAN ALENKAM, MCNAMARA MEAGHAN, LEVY OFER, Levy O. Endotoxin-directed innate immunity in tracheal aspirates of mechanically ventilated human neonates. Pediatr Res 2009; 66:191-6. [PMID: 19390484 PMCID: PMC3992717 DOI: 10.1203/pdr.0b013e3181aa33d7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Mechanical ventilation of preterm infants is associated with pulmonary inflammation. Intubated infants often develop bacterial tracheal colonization, but little is known about endotoxin in tracheal aspirates (TAs) or the mobilization of innate immunity toward endotoxin, a potent stimulus that contributes to inflammatory disease. We characterized mobilization of endotoxin-directed innate immunity in TAs from an observational cohort of mechanically ventilated neonates. TA supernatants (n = 42; GA = 23-40 wk, postnatal age = 1-71 d) were assayed for endotoxin (Limulus amoebocyte lysate assay) and endotoxin-modulating proteins: bactericidal/ permeability-increasing protein (BPI), LPS-binding protein (LBP), and soluble cell differentiation antigen 14 (sCD14). TA cellular BPI was measured by ELISA, Western blot, flow cytometry, and bactericidal assay. TA mRNAs encoding endotoxin-modulating proteins were measured by quantitative real-time PCR (qRT-PCR). Endotoxin in TA supernatants was proportional to both postnatal age and polymorphonuclear leukocytes (PMN). Neonatal TAs were rich in PMN containing BPI and expressed mRNAs encoding Toll-like receptor (TLR) 4, CD14, and myeloid differentiation protein 2 (MD-2). Extracellular BPI was consistently detectable and correlated with TA PMN and GA. Both extracellular- and cellular-BPI increased during the first postnatal week. TA extracellular BPI, LBP, and sCD14 were positively correlated. TAs from intubated neonates demonstrate endotoxin accumulation and mobilization of endotoxin-directed innate immunity, potentially contributing to pulmonary inflammation.
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Affiliation(s)
- KATHERYN E. NATHE
- Division of Newborn Medicine, Children's Hospital Boston, Boston, MA 02115, USA, Department of Newborn Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA, Harvard Medical School, Boston, MA 02115, USA
| | - RICHARD PARAD
- Division of Newborn Medicine, Children's Hospital Boston, Boston, MA 02115, USA, Department of Newborn Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA, Harvard Medical School, Boston, MA 02115, USA
| | - LINDA J. VAN MARTER
- Division of Newborn Medicine, Children's Hospital Boston, Boston, MA 02115, USA, Department of Newborn Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA, Harvard Medical School, Boston, MA 02115, USA
| | - CARA A. LUND
- Division of Infectious Diseases, Children's Hospital Boston, Boston, MA 02115, USA
| | - EUGÉNIE E. SUTER
- Division of Infectious Diseases, Children's Hospital Boston, Boston, MA 02115, USA
| | - SONIA HERNANDEZ-DIAZ
- Division of Pharmacoepidemiology, Harvard School of Public Health, Boston, MA, 02115, USA., Harvard Medical School, Boston, MA 02115, USA
| | | | - EVA IKONOMU
- Division of Infectious Diseases, Children's Hospital Boston, Boston, MA 02115, USA
| | - JO ANN MOREY
- Department of Newborn Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - ALENKA M. ZEMAN
- Department of Newborn Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - MEAGHAN MCNAMARA
- Department of Newborn Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - OFER LEVY
- Division of Infectious Diseases, Children's Hospital Boston, Boston, MA 02115, USA, Harvard Medical School, Boston, MA 02115, USA,Correspondence and requests for reprints should be addressed to: Ofer Levy M.D., Ph.D. Harvard Medical School Department of Medicine, Division of Infectious Diseases Children's Hospital Boston 300 Longwood Avenue, Enders 854 Boston, MA 02115 Office phone: (617) 919-2904 FAX: (617) 730-0255
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82
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Hersh CP, DeMeo DL, Raby BA, Litonjua AA, Sylvia JS, Sparrow D, Reilly JJ, Silverman EK. Genetic Linkage and Association Analysis of COPD-Related Traits on Chromosome 8p. COPD 2009; 3:189-94. [PMID: 17361499 DOI: 10.1080/15412550601009321] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Genome-wide linkage analysis in the Boston Early-Onset Chronic Obstructive Pulmonary Disease (COPD) Study has demonstrated significant evidence of linkage to chromosome 8p for forced expiratory volume in 1 second, an important COPD-related phenotype. In this study, we sought to fine map the linkage peak and to test variants in two candidate genes for association with COPD and related traits. In a variance component linkage analysis on chromosome 8, including seven additional short tandem repeat markers, the logarithm of the odds of linkage score was reduced from 3.30 to 1.80 (at 1 cM). Five single nucleotide polymorphisms (SNPs) in Defensin Beta-1 (DEFB1) were genotyped in the Boston Early-Onset COPD Study families; none was significantly associated. Four SNPs and an insertion-deletion polymorphism in Macrophage Scavenger Receptor-1 (MSR1) were also genotyped in the family-based study. A coding variant (Pro275Ala) was marginally associated with two qualitative airflow obstruction traits (p < or = 0.02). This SNP showed a trend toward association in a case-control study comparing participants in the National Emphysema Treatment Trial to smoker controls (p = 0.07). Despite the reduced support for linkage upon further analysis, it remains possible that chromosome 8p contains a gene that influences COPD susceptibility. There is marginal, though not convincing, evidence for association with MSR1.
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Affiliation(s)
- Craig P Hersh
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA.
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83
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Sagel SD, Sontag MK, Accurso FJ. Relationship between antimicrobial proteins and airway inflammation and infection in cystic fibrosis. Pediatr Pulmonol 2009; 44:402-9. [PMID: 19283840 DOI: 10.1002/ppul.21028] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Antimicrobial proteins are important in lung defense and are potential therapeutic agents in chronic airways infection such as seen in cystic fibrosis (CF). In preparation for future clinical studies, we sought (1) to determine levels of three antimicrobial proteins [lactoferrin, lysozyme, and secretory leukoprotease inhibitor (SLPI)] in the CF airway and (2) to examine the relationships between these antimicrobial proteins and airway inflammation and infection. We examined bronchoalveolar lavage fluid (BALF) from 45 individuals with CF and 23 disease control individuals. Airway inflammation was measured through BALF neutrophil counts and neutrophil elastase activity. Infection was assessed through quantitative counts of CF-related bacterial pathogens. BALF lysozyme activity and lactoferrin levels were elevated in individuals with CF compared to controls whereas SLPI levels were not different between the groups. Among the CF subjects, lysozyme activity and lactoferrin increased with age while SLPI decreased with age. Lysozyme activity and lactoferrin concentrations correlated positively with neutrophil counts but not with bacterial colony counts. SLPI levels were inversely related to both neutrophil counts and bacterial colony counts. This study provides information concerning the levels of antimicrobial proteins present in the CF airway that are relevant to future clinical trials of these compounds and demonstrates clear relationships between antimicrobial protein-specific levels and airway inflammation and infection.
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Affiliation(s)
- Scott D Sagel
- Department of Pediatrics, The Children's Hospital and University of Colorado Denver School of Medicine, Aurora, Colorado 80045, USA.
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84
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Lopera D, Aristizabal BH, Restrepo A, Cano LE, González A. Lysozyme plays a dual role against the dimorphic fungus Paracoccidioides brasiliensis. Rev Inst Med Trop Sao Paulo 2008; 50:169-75. [PMID: 18604417 DOI: 10.1590/s0036-46652008000300008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2007] [Accepted: 04/14/2008] [Indexed: 11/22/2022] Open
Abstract
In order to determine the role of lysozyme, an antimicrobial peptide belonging to the innate immune system, against the dimorphic fungus Paracoccidioides brasiliensis, co-cultures of the MH-S murine alveolar macrophages cell line with P. brasiliensis conidia were done; assays to evaluate the effect of physiological and inflammatory concentrations of lysozyme directly on the fungus life cycle were also undertaken. We observed that TNF-alpha-activated macrophages significantly inhibited the conidia to yeast transition (p = 0.0043) and exerted an important fungicidal effect (p = 0.0044), killing 27% more fungal propagules in comparison with controls. Nonetheless, after adding a selective inhibitor of lysozyme, the fungicidal effect was reverted. When P. brasiliensis propagules were exposed directly to different concentrations of lysozyme, a dual effect was observed. Physiologic concentrations of the enzyme facilitated the conidia-to-yeast transition process (p < 0.05). On the contrary, inflammatory concentrations impaired the normal temperature-dependent fungal transition (p < 0.0001). When yeast cells were exposed to lysozyme, irrespective of concentration, the multiple-budding ability was badly impaired (p < 0.0001). In addition, ultra-structural changes such as subcellular degradation, fusion of lipid vacuoles, lamellar structures and interruption of the fibrillar layer were observed in lysozyme exposed conidia. These results suggest that lysozyme appears to exert a dual role as part of the anti-P. brasiliensis defense mechanisms.
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Affiliation(s)
- Damaris Lopera
- Medical and Experimental Mycology Group, Corporación para Investigaciones Biológicas, Carrera 72A No. 78B-141, Medellín, Colombia
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85
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Méndez-Samperio P. Role of antimicrobial peptides in host defense against mycobacterial infections. Peptides 2008; 29:1836-41. [PMID: 18582513 DOI: 10.1016/j.peptides.2008.05.024] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Revised: 05/28/2008] [Accepted: 05/30/2008] [Indexed: 11/28/2022]
Abstract
Worldwide, tuberculosis remains the most important infectious disease causing morbidity and death. Currently, at least one-third of the world's population is infected with Mycobacterium tuberculosis. In addition, the World Health Organization estimates that about 8-10 million new tuberculosis cases occur annually worldwide and this incidence is currently increasing. Moreover, multidrug-resistant tuberculosis has been increasing in incidence in many areas during the past decade. These situations underscore the importance of the development of new therapeutic agents against mycobacterial infectious diseases. In this article, it is review current progress in the understanding of antimicrobial peptides as potential candidates to develop an alternative/adjunct therapeutic strategy against tuberculosis. This immunoadjunctive therapy might be evaluated in the context of possible drug resistance. This review also summarizes the knowledge about the functions of antimicrobial peptides in the pulmonary innate host defense system and their role in mycobacterial infection, and at the same time outlines recent advances in our understanding of the combined effect of antimicrobial peptides and anti-tuberculosis drugs against intracellular mycobacteria. A concerted effort should now focus on the clinical application of antimicrobial peptides for their practical use.
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Affiliation(s)
- Patricia Méndez-Samperio
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, México, D.F. 11340, Mexico.
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86
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Abstract
OBJECTIVE/HYPOTHESIS The diverse antipathogenic action of lactoferrin has been well characterized. In addition, it is the human body's only known antimicrobial peptide with antibiofilm properties. The purpose of this study was to examine the nasal mucosal expression of lactoferrin in the biofilm-mediated disease, chronic rhinosinusitis (CRS). STUDY DESIGN/METHODS Nasal biopsies from 41 CRS patients and 21 healthy controls were analyzed using confocal scanning laser microscopy (CSLM) and scanning electron microscopy (SEM) for the presence of biofilms. The messenger ribonucleic acid (mRNA) and protein level of lactoferrin in this tissue were also determined by quantitative real-time reverse-transcriptase polymerase chain reaction (qRT-PCR) and enzyme linked immunosorbent assay (ELISA), respectively. RESULTS Lactoferrin expression in chronic rhinosinusitis patients at both mRNA and protein level was downregulated relative to controls. Biofilm-positive CRS patients showed a much greater reduction in lactoferrin expression than biofilm-negative patients; mRNA median fold change biofilm positive = 0.03 (interquartile range 0.005-0.15) and biofilm-negative CRS median fold change = 0.49 (interquartile range 0.15-0.81) with median lactoferrin protein expression biofilm-positive patients' median lactoferrin protein expression = 32.58 ng/mL (interquartile range 8.67-59.9 ng/mL) and biofilm-negative patients' median lactoferrin expression = 114.40 ng/mL (interquartile range 75.41-163.1 ng/mL). CONCLUSIONS Genetic, transcriptional, or translational deficiencies in lactoferrin synthesis may reduce the functional level of this important antimicrobial/antibiofilm peptide in the nasal secretions of CRS patients, predisposing certain individuals to bacterial colonization, biofilm development, and recalcitrant sinus disease.
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87
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Omsland A, Miranda KM, Friedman RL, Boitano S. Bordetella bronchiseptica responses to physiological reactive nitrogen and oxygen stresses. FEMS Microbiol Lett 2008; 284:92-101. [PMID: 18462394 DOI: 10.1111/j.1574-6968.2008.01181.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Bordetella bronchiseptica can establish prolonged airway infection consistent with a highly developed ability to evade mammalian host immune responses. Upon initial interaction with the host upper respiratory tract mucosa, B. bronchiseptica are subjected to antimicrobial reactive nitrogen species (RNS) and reactive oxygen species (ROS), effector molecules of the innate immune system. However, the responses of B. bronchiseptica to redox species at physiologically relevant concentrations (nM-microM) have not been investigated. Using predicted physiological concentrations of nitric oxide (NO), superoxide and hydrogen peroxide (H2O2) on low numbers of CFU of B. bronchiseptica, all redox active species displayed dose-dependent antimicrobial activity. Susceptibility to individual redox active species was significantly increased upon introduction of a second species at subantimicrobial concentrations. An increased bacteriostatic activity of NO was observed relative to H2O2. The understanding of Bordetella responses to physiologically relevant levels of exogenous RNS and ROS will aid in defining the role of endogenous production of these molecules in host innate immunity against Bordetella and other respiratory pathogens.
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Affiliation(s)
- Anders Omsland
- Department of Cell Biology and Anatomy, Arizona Health Sciences Center, University of Arizona, AZ 85724-5030, USA
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88
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Chen J, Ryu S, Gharib SA, Goodlett DR, Schnapp LM. Exploration of the normal human bronchoalveolar lavage fluid proteome. Proteomics Clin Appl 2008; 2:585-95. [PMID: 21136857 PMCID: PMC4432467 DOI: 10.1002/prca.200780006] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2007] [Indexed: 12/19/2022]
Abstract
We obtained insight into normal lung function by proteome analysis of bronchoalveolar lavage fluid (BALF) from six normal human subjects using a "Lyse-N-Go' shotgun proteomic protocol. Intra-sample variation was calculated using three different label-free methods, (i) protein sequence coverage; (ii) peptide spectral counts and (iii) peptide single-ion current areas (PICA), which generates protein expression data by summation of the area under the curve for a given peptide single-ion current trace and then adding values for all peptides from that same parent protein. PICA gave the least intra-subject variability and was used to calculate differences in protein expression between the six subjects. We observed an average threefold inter-sample variability, which affects analysis of changes in protein expression that occur in different diseases. We detected 167 unique proteins with >100 proteins detected in each of the six individual BAL samples, 42 of which were common to all six subjects. Gene ontology analysis demonstrated enrichment of several biological processes in the lung, reflecting its expected role in gas exchange and host defense as an immune organ. The same biological processes were enriched compared to either plasma or total genome proteome, suggesting an active enrichment of plasma proteins in the lung rather than passive capillary leak.
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Affiliation(s)
- Jinzhi Chen
- Department of Medicinal Chemistry, University of Washington, Seattle, WA, USA
| | - Soyoung Ryu
- Department of Medicinal Chemistry, University of Washington, Seattle, WA, USA
| | - Sina A. Gharib
- Division of Pulmonary and Critical Care Medicine, Harborview Medical Center, University of Washington, Seattle, WA, USA
| | - David R. Goodlett
- Department of Medicinal Chemistry, University of Washington, Seattle, WA, USA
| | - Lynn M. Schnapp
- Division of Pulmonary and Critical Care Medicine, Harborview Medical Center, University of Washington, Seattle, WA, USA
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89
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Wang Y, Shan T, Xu Z, Liu J, Feng J. Effect of lactoferrin on the growth performance, intestinal morphology, and expression of PR-39 and protegrin-1 genes in weaned piglets. J Anim Sci 2008; 84:2636-41. [PMID: 16971564 DOI: 10.2527/jas.2005-544] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A total of 90 weaned female pigs (Duroc x Landrace x Yorkshire) were used in a 15-d growth experiment to investigate the effect of lactoferrin on growth performance, intestinal morphology, and expression of PR-39 and protegrin-1 genes. The pigs were allocated on the basis of BW and litter to 3 dietary treatments in a randomized complete block design. There were 3 replicate pens per treatment, and the pigs were grouped with 10 pigs per pen. The dietary treatments were (1) basal diet; (2) basal diet + 20 mg of flavomycin/kg + 110 mg of aureomycin/kg; (3) basal diet + 1.0 g of lactoferrin/kg. Six pigs, randomly selected from each treatment (2 piglets/pen) were slaughtered for intestinal morphology and expression of PR-39 and protegrin-1 genes at the end of the experiment. Supplementation with lactoferrin improved growth performance; it increased ADG by 41.80% (P < 0.01) and efficiency of gain (G:F) by 17.20% (P < 0.05). Intestinal villus height was increased by 15.30% (P < 0.05), and crypt depth was decreased by 9.60% (P < 0.05). Supplemental lactoferrin increased the relative abundance of mRNA for PR-39 and protegrin-1 by 143% (P < 0.01) and 217% (P < 0.01), respectively. The use of lactoferrin as an additive to improve nonspecific immunity and strengthen host defenses would be good a method of defending weaned pigs from infections and weanling stress.
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Affiliation(s)
- Y Wang
- Institute of Feed Science, Zhejiang University, The Key Laboratory of Molecular Animal Nutrition, Ministry of Education, No. 164 Qiutao North Road, Hangzhou 310029, P. R. China.
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90
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Rengarajan J, Murphy E, Park A, Krone CL, Hett EC, Bloom BR, Glimcher LH, Rubin EJ. Mycobacterium tuberculosis Rv2224c modulates innate immune responses. Proc Natl Acad Sci U S A 2008; 105:264-9. [PMID: 18172199 PMCID: PMC2224198 DOI: 10.1073/pnas.0710601105] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2007] [Indexed: 01/15/2023] Open
Abstract
Tuberculosis remains a major global health problem that kills up to 2 million people annually. Central to the success of Mycobacterium tuberculosis (Mtb) as a pathogen is its ability to evade host immunity and to establish a chronic infection. Although its primary intracellular niche is within macrophages, the underlying molecular mechanisms are poorly understood. Here we show that Rv2224c, a cell envelope-associated predicted protease, is critical for Mtb virulence. Disruption of Rv2224c led to prolonged survival of infected mice and highly reduced lung pathology. Absence of Rv2224c enhanced host innate immune responses, compromised the intracellular survival of Mtb in macrophages, and increased its susceptibility to lysozyme. We provide insights into the molecular basis for Rv2224c function by showing that Rv2224c activity promotes processing and extracellular release of the Mtb protein, GroEL2. Inhibition of Rv2224c and its targets offers opportunities for therapeutic interventions and immune-modulatory strategies.
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Affiliation(s)
- Jyothi Rengarajan
- *Department of Immunology and Infectious Diseases, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115; and
| | - Elissa Murphy
- *Department of Immunology and Infectious Diseases, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115; and
| | - Arnold Park
- *Department of Immunology and Infectious Diseases, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115; and
| | - Cassandra L. Krone
- *Department of Immunology and Infectious Diseases, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115; and
| | - Erik C. Hett
- *Department of Immunology and Infectious Diseases, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115; and
| | - Barry R. Bloom
- *Department of Immunology and Infectious Diseases, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115; and
| | - Laurie H. Glimcher
- *Department of Immunology and Infectious Diseases, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115; and
- Department of Medicine, Harvard Medical School, Boston, MA 02115
| | - Eric J. Rubin
- *Department of Immunology and Infectious Diseases, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115; and
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91
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Berlutti F, Superti F, Nicoletti M, Morea C, Frioni A, Ammendolia M, Battistoni A, Valenti P. Bovine Lactoferrin Inhibits the Efficiency of Invasion of Respiratory A549 Cells of Different Iron-Regulated Morphological Forms of Pseudomonas Aeruginosa and Burkholderia Cenocepacia. Int J Immunopathol Pharmacol 2008; 21:51-9. [DOI: 10.1177/039463200802100107] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Pseudomonas aeruginosa and Burkholderia cenocepacia are two important opportunistic respiratory pathogens of cystic fibrosis (CF) patients. Infections caused by these microorganisms are particularly difficult to eradicate because they are usually highly resistant to several currently available broad-spectrum antibiotics. Lactoferrin (Lf), a glycoprotein found in physiological fluids of mammals and present at high concentrations in infected and inflamed tissues, plays an important role in the natural defence mechanism against pathogens and in immune regulation. In the present study, we evaluate the ability of bovine lactoferrin (bLf) to influence P. aeruginosa PAO1 and B. cenocepacia PV1 adhesiveness and invasiveness, using the A549 human bronchial cell line. Three different iron-induced morphological forms of bacteria (free-living, aggregates and biofilm) were assayed. The addition of bLf to cells just before infection had little influence on adhesion efficiency for all three of the morphological forms of B. cenocepacia PV1, while a slight increase in adhesion efficiency by P. aeruginosa PAO1 was noticed. Conversely, invasion of all three morphological forms of both P. aeruginosa and B. cenocepacia was strongly inhibited by the presence of bLf, independently of its degree of iron-binding activity. This is the first report demonstrating an anti-invasive property of bLf for strains of P. aeruginosa and B. cenocepacia.
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Affiliation(s)
| | - F. Superti
- Department of Technology and Health, National Institute of Health, Rome
| | - M. Nicoletti
- Department of Biomedical Sciences, University “G d'Annunzio”, Chieti
| | | | | | - M.G. Ammendolia
- Department of Technology and Health, National Institute of Health, Rome
| | - A. Battistoni
- Department of Biology, University “Tor Vergata”, Rome, Italy
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92
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Donnarumma G, Paoletti I, Buommino E, Iovene MR, Tudisco L, Cozza V, Tufano MA. Anti-inflammatory effects of moxifloxacin and human beta-defensin 2 association in human lung epithelial cell line (A549) stimulated with lipopolysaccharide. Peptides 2007; 28:2286-92. [PMID: 17996331 DOI: 10.1016/j.peptides.2007.09.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Revised: 09/12/2007] [Accepted: 09/17/2007] [Indexed: 11/19/2022]
Abstract
Epithelia in the human airways, from the nasal aperture to the alveoli, are covered in a protective film of fluid containing a number of antimicrobial proteins. Defensins are single-chain, strongly cationic peptides and are one of the most extensively studied classes of antimicrobial peptides. Moxifloxacin (MXF) is a fluoroquinolone that acts against both Gram positive and Gram negative bacteria. In this study, we evaluated the effects of HBD2, MXF and the association MXF/HBD2 on some cytokines and on the ICAM-1 expression in LPS-stimulated A549 cells. Our results suggest that by lowering the epithelial cell-derived IL-1beta, IL-6, IL-8 and ICAM-1 expression, the MXF/HBD2 association interferes with the multifunctional cytokine network evolving during inflammatory processes of the respiratory tract; this anti-inflammatory potential could be of great value in the treatment of inflammatory disorders.
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Affiliation(s)
- Giovanna Donnarumma
- Faculty of Medicine and Surgery, Second University of Naples, Department of Experimental Medicine, Microbiology and Clinical Microbiology, Via Costantinopoli 16, 80138 Naples, Italy
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93
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Mossel EC, Wang J, Jeffers S, Edeen KE, Wang S, Cosgrove GP, Funk CJ, Manzer R, Miura TA, Pearson LD, Holmes KV, Mason RJ. SARS-CoV replicates in primary human alveolar type II cell cultures but not in type I-like cells. Virology 2007; 372:127-35. [PMID: 18022664 PMCID: PMC2312501 DOI: 10.1016/j.virol.2007.09.045] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2007] [Revised: 08/03/2007] [Accepted: 09/28/2007] [Indexed: 02/07/2023]
Abstract
Severe acute respiratory syndrome (SARS) is a disease characterized by diffuse alveolar damage. We isolated human alveolar type II cells and maintained them in a highly differentiated state. Type II cell cultures supported SARS-CoV replication as evidenced by RT-PCR detection of viral subgenomic RNA and an increase in virus titer. Virus titers were maximal by 24 h and peaked at approximately 105 pfu/mL. Two cell types within the cultures were infected. One cell type was type II cells, which were positive for SP-A, SP-C, cytokeratin, a type II cell-specific monoclonal antibody, and Ep-CAM. The other cell type was composed of spindle-shaped cells that were positive for vimentin and collagen III and likely fibroblasts. Viral replication was not detected in type I-like cells or macrophages. Hence, differentiated adult human alveolar type II cells were infectible but alveolar type I-like cells and alveolar macrophages did not support productive infection.
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Affiliation(s)
- Eric C Mossel
- Colorado State University, Fort Collins, CO 80523, USA.
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94
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Immunoglobulins in nasal secretions of patients with allergic rhinitis and chronic rhinosinusitis. Eur Arch Otorhinolaryngol 2007; 265:539-42. [PMID: 17989989 DOI: 10.1007/s00405-007-0515-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2007] [Accepted: 10/18/2007] [Indexed: 10/22/2022]
Abstract
Allergic rhinitis and chronic rhinosinusitis are the most frequently encountered inflammatory reactions of the sinonasal mucosa. Nasal-associated lymphoid tissue has been suggested as an inductive site for humoral and cellular immune responses in the upper respiratory tract. Immunoglobulins are important elements in human adaptive immune responses and deficiencies of serum immunoglobulins may be associated with recurrent or refractory infections. However, the local humoral immune response to offending antigens in the nasal environment has not been well elucidated. To determine the levels of IgA and IgG subclasses antibodies in the nasal secretions of patients with allergic rhinitis and chronic rhinosinusitis, 25 patients with allergic rhinitis and 20 with chronic rhinosinusitis were included and their nasal secretions were collected to measure the levels of secretary IgA (sIgA), total IgA (tIgA), and IgG subclasses antibodies. There was a significant elevation of IgG(3) in the nasal secretions of patients with chronic rhinosinusitis. No difference was noted in the levels of sIgA, tIgA, IgG1, IgG2 and IgG4 among the three groups. The local defense mechanism of nose reacts to microorganisms and pathogenic antigens by inducing the adaptive humoral immune response to increase the amount of immunoglobulins, with IgG3 being the major up-regulated antibody.
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Christensen RD, Rigby G, Schmutz N, Lambert DK, Wiedmeier SE, Burnett J, Scoffield SH, Muelleck R, Snow K, Woodhead DD, Snow GL. ETCare: a randomized, controlled, masked trial comparing two solutions for upper airway care in the NICU. J Perinatol 2007; 27:479-84. [PMID: 17568755 DOI: 10.1038/sj.jp.7211779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Small quantities of normal saline are sometimes instilled into the endotracheal tube of intubated neonates, to assist with the removal of thick secretions and maintain patency of the endotracheal tube. However, saline is detrimental to the innate immune system of the upper airway mucosa, rapidly unfolding and inactivating antimicrobial peptides such as LL-37. We previously reported the preparation and feasibility testing of 'ETCare', a low-sodium, physiologically based solution for airway care, and we now report results of a randomized, masked, controlled, two-centered study testing ETCare vs sterile saline among 60 intubated NICU patients. STUDY DESIGN Sixty intubated NICU patients were randomized to having their airway care with ETCare vs saline. Three hypotheses were tested: (1) tolerance - patients will tolerate ETCare for airway care as well as they tolerate saline, (2) nosocomial infections - ETCare will result in fewer tracheal aspirates where organisms grow and fewer cases of nosocomial sepsis, and (3) chronic lung disuse - ETCare will result in fewer patients discharged home on supplemental O2. RESULTS Thirty NICU patients with an endotracheal tube in place were randomized to receive their airway care with ETCare, and 30 to receive their care with saline. Only the pharmacist was aware of the randomization; the two solutions were visually indistinguishable and were dispensed in identical syringes. Tolerance of the solutions was similar. The ETCare recipients had trends toward fewer positive blood cultures (odds ratios (OR), 0.48; 95% confidence interval (CI), 0.13 to 1.68), and fewer discharges home on supplemental O2 (OR, 0.43; 95% CI, 0.14 to 1.32; P=0.075). CONCLUSIONS On the basis of this study and our previous 10-patient feasibility trial, we maintain that, for airway care, intubated NICU patients tolerate ETCare as well as saline. Data from this study can be used in estimating the sample sizes needed for a phase III trial. We speculate that such a trial will demonstrate that, compared with saline, ETCare will result in fewer nosocomial infections and less chronic lung disease.
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Affiliation(s)
- R D Christensen
- Neonatal Intensive Care, McKay-Dee Hospital Center, Intermountain Healthcare, Ogden, UT 84403, USA.
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96
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Shu Q, Shi Z, Zhao Z, Chen Z, Yao H, Chen Q, Hoeft A, Stuber F, Fang X. Protection against Pseudomonas aeruginosa pneumonia and sepsis-induced lung injury by overexpression of beta-defensin-2 in rats. Shock 2006; 26:365-71. [PMID: 16980883 DOI: 10.1097/01.shk.0000224722.65929.58] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Beta-defensin-2 (BD-2), a small cationic antimicrobial peptide, was first described to be an inducible defensin at the epithelial surfaces. In vitro studies have demonstrated that it may play a pivotal role in the anti-inflammatory immune response in addition to its antimicrobial activity. The purpose of this study was to evaluate the effect of overexpression of BD-2 on lung injury to crudely investigate whether the function of BD-2 in the lung attributed to both antimicrobial action and modulation of the immune response. Recombinant adenovirus carrying an expression cassette of rat BD-2 or control adenovirus carrying empty vector was administered intratracheally to Sprague-Dawley rats 48 h before performing acute lung injury, which was induced either by Pseudomonas aeruginosa infection or by cecal ligation and double puncture (2CLP). In vivo antimicrobial activity of BD-2, histological changes of the lungs in both infectious and 2CLP models, pulmonary intracellular adhesion molecule-1 protein level, as well as the 7-day survival rate in the latter model were determined. Amounts of the P. aeruginosa in the lung with BD-2 overexpression were significantly lower compared with that in controls (2.87+/-0.76x10(4) colony-forming units [CFU]/mL vs. 2.49+/-0.74x10(6) CFU/mL, P<0.05). Overexpression of BD-2 reduced alveolar damage, interstitial edema, and infiltration of neutrophils in both models. Furthermore, in the 2CLP model, recombinant BD-2 not only significantly decreased protein levels of intracellular adhesion molecule-1 in lung tissue at 24, 36, and 72 h after 2CLP (P<0.05), but also significantly improved the survival of rats (P<0.05). The CFU of abdominal bacteria was comparable to that in the control rats (P>0.05). Therefore, overexpression of BD-2 protects against P. aeruginosa pneumonia and 2CLP-induced lung injury based on its antimicrobial and anti-inflammatory activities, respectively. Modulating the expression level of BD-2 may serve as an approach to attenuate lung injury.
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Affiliation(s)
- Qiang Shu
- Children's Hospital, School of Medicine and National Key Laboratory of Infection Disease, Zhejiang University, Hangzhou, China
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97
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Matsui H, Wagner VE, Hill DB, Schwab UE, Rogers TD, Button B, Taylor RM, Superfine R, Rubinstein M, Iglewski BH, Boucher RC. A physical linkage between cystic fibrosis airway surface dehydration and Pseudomonas aeruginosa biofilms. Proc Natl Acad Sci U S A 2006; 103:18131-6. [PMID: 17116883 PMCID: PMC1838718 DOI: 10.1073/pnas.0606428103] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Indexed: 11/18/2022] Open
Abstract
A vexing problem in cystic fibrosis (CF) pathogenesis has been to explain the high prevalence of Pseudomonas aeruginosa biofilms in CF airways. We speculated that airway surface liquid (ASL) hyperabsorption generates a concentrated airway mucus that interacts with P. aeruginosa to promote biofilms. To model CF vs. normal airway infections, normal (2.5% solids) and CF-like concentrated (8% solids) mucus were prepared, placed in flat chambers, and infected with an approximately 5 x 10(3) strain PAO1 P. aeruginosa. Although bacteria grew to 10(10) cfu/ml in both mucus concentrations, macrocolony formation was detected only in the CF-like (8% solids) mucus. Biophysical and functional measurements revealed that concentrated mucus exhibited properties that restrict bacterial motility and small molecule diffusion, resulting in high local bacterial densities with high autoinducer concentrations. These properties also rendered secondary forms of antimicrobial defense, e.g., lactoferrin, ineffective in preventing biofilm formation in a CF-like mucus environment. These data link airway surface liquid hyperabsorption to the high incidence of P. aeruginosa biofilms in CF via changes in the hydration-dependent physical-chemical properties of mucus and suggest that the thickened mucus gel model will be useful to develop therapies of P. aeruginosa biofilms in CF airways.
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Affiliation(s)
| | - Victoria E. Wagner
- Department of Microbiology and Immunology, University of Rochester, Rochester, NY 14627
| | - David B. Hill
- *Cystic Fibrosis/Pulmonary Research and Treatment Center and
| | - Ute E. Schwab
- *Cystic Fibrosis/Pulmonary Research and Treatment Center and
| | - Troy D. Rogers
- *Cystic Fibrosis/Pulmonary Research and Treatment Center and
| | - Brian Button
- *Cystic Fibrosis/Pulmonary Research and Treatment Center and
| | | | | | | | - Barbara H. Iglewski
- Department of Microbiology and Immunology, University of Rochester, Rochester, NY 14627
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98
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Fischer H, Widdicombe JH. Mechanisms of acid and base secretion by the airway epithelium. J Membr Biol 2006; 211:139-50. [PMID: 17091214 PMCID: PMC2929530 DOI: 10.1007/s00232-006-0861-0] [Citation(s) in RCA: 163] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2006] [Revised: 04/15/2006] [Indexed: 12/15/2022]
Abstract
One of the main functions of the airway epithelium is to inactivate and remove infectious particles from inhaled air and thereby prevent infection of the distal lung. This function is achieved by mucociliary and cough clearance and by antimicrobial factors present in the airway surface liquid (ASL). There are indications that airway defenses are affected by the pH of the ASL and historically, acidification of the airway surfaces has been suggested as a measure of airway disease. However, even in health, the ASL is slightly acidic, and this acidity might be part of normal airway defense. Only recently research has focused on the mechanisms responsible for acid and base secretion into the ASL. Advances resulted from research into the airway disease associated with cystic fibrosis (CF) after it was found that the CFTR Cl(-) channel conducts HCO (3) (-) and, therefore, may contribute to ASL pH. However, the acidity of the ASL indicated parallel mechanisms for H(+) secretion. Recent investigations identified several H(+) transporters in the apical membrane of the airway epithelium. These include H(+) channels and ATP-driven H(+) pumps, including a non-gastric isoform of the H(+)-K(+) ATPase and a vacuolar-type H(+) ATPase. Current knowledge of acid and base transporters and their potential roles in airway mucosal pH regulation is reviewed here.
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Affiliation(s)
- Horst Fischer
- Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA.
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99
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Moskwa P, Lorentzen D, Excoffon KJDA, Zabner J, McCray PB, Nauseef WM, Dupuy C, Bánfi B. A novel host defense system of airways is defective in cystic fibrosis. Am J Respir Crit Care Med 2006; 175:174-83. [PMID: 17082494 PMCID: PMC2720149 DOI: 10.1164/rccm.200607-1029oc] [Citation(s) in RCA: 215] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE The respiratory tract is constantly exposed to airborne microorganisms. Nevertheless, normal airways remain sterile without recruiting phagocytes. This innate immune activity has been attributed to mucociliary clearance and antimicrobial polypeptides of airway surface liquid. Defective airway immunity characterizes cystic fibrosis (CF), a disease caused by mutations in the CF transmembrane conductance regulator, a chloride channel. The pathophysiology of defective immunity in CF remains to be elucidated. OBJECTIVE We investigated the ability of non-CF and CF airway epithelia to kill bacteria through the generation of reactive oxygen species (ROS). METHODS ROS production and ROS-mediated bactericidal activity were determined on the apical surfaces of human and rat airway epithelia and on cow tracheal explants. MEASUREMENTS AND MAIN RESULTS Dual oxidase enzyme of airway epithelial cells generated sufficient H(2)O(2) to support production of bactericidal hypothiocyanite (OSCN(-)) in the presence of airway surface liquid components lactoperoxidase and thiocyanate (SCN(-)). This OSCN(-) formation eliminated Staphylococcus aureus and Pseudomonas aeruginosa on airway mucosal surfaces, whereas it was nontoxic to the host. In contrast to normal epithelia, CF epithelia failed to secrete SCN(-), thereby rendering the oxidative antimicrobial system inactive. CONCLUSIONS These data indicate a novel innate defense mechanism of airways that kills bacteria via ROS and suggest a new cellular and molecular basis for defective airway immunity in CF.
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Affiliation(s)
- Patryk Moskwa
- Department of Anatomy, University of Iowa, Coralville, IA 52241, USA
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100
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Nam HY, Ahn EK, Kim HJ, Lim Y, Lee CB, Lee KY, Vallyathan V. Diesel exhaust particles increase IL-1beta-induced human beta-defensin expression via NF-kappaB-mediated pathway in human lung epithelial cells. Part Fibre Toxicol 2006; 3:9. [PMID: 16723032 PMCID: PMC1524805 DOI: 10.1186/1743-8977-3-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2005] [Accepted: 05/25/2006] [Indexed: 02/07/2023] Open
Abstract
Background Human β-defensin (hBD)-2, antimicrobial peptide primarily induced in epithelial cells, is a key factor in the innate immune response of the respiratory tract. Several studies showed increased defensin levels in both inflammatory lung diseases, such as cystic fibrosis, diffuse panbronchiolitis, idiopathic pulmonary fibrosis and acute respiratory distress syndrome, and infectious diseases. Recently, epidemiologic studies have demonstrated acute and serious adverse effects of particulate air pollution on respiratory health, especially in people with pre-existing inflammatory lung disease. To elucidate the effect of diesel exhaust particles (DEP) on pulmonary innate immune response, we investigated the hBD-2 and interleukin-8 (IL-8) expression to DEP exposure in interleukin-1 beta (IL-1β)-stimulated A549 cells. Results IL-1β markedly up-regulated the hBD-2 promoter activity, and the subsequent DEP exposure increased dose-dependently the expression of hBD-2 and inflammatory cytokine IL-8 at the transcriptional level. In addition, DEP further induced the NF-κB activation in IL-1β-stimulated A549 cells more rapidly than in unstimulated control cells, which was showed by nuclear translocation of p65 NF-κB and degradation of IκB-α. The experiment using two NF-κB inhibitors, PDTC and MG132, confirmed that this increase of hBD-2 expression following DEP exposure was regulated through NF-κB-mediated pathway. Conclusion These results demonstrated that DEP exposure increases the expression of antimicrobial peptide and inflammatory cytokine at the transcriptional level in IL-1β-primed A549 epithelial cells and suggested that the increase is mediated at least partially through NF-κB activation. Therefore, DEP exposure may contribute to enhance the airway-responsiveness especially on the patients suffering from chronic respiratory disease.
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Affiliation(s)
- Hae Yun Nam
- Catholic Neuroscience Center, The Catholic University of Korea, Seoul 137–701, Korea
- Department of Occupational & Environmental Medicine, St. Mary's Hospital, The Catholic University of Korea, Seoul 150–713, Korea
| | - Eun-Kyung Ahn
- Department of Occupational & Environmental Medicine, St. Mary's Hospital, The Catholic University of Korea, Seoul 150–713, Korea
| | - Hyung Jung Kim
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul 135–270, Korea
| | - Young Lim
- Department of Occupational & Environmental Medicine, St. Mary's Hospital, The Catholic University of Korea, Seoul 150–713, Korea
| | - Chun Beoun Lee
- Environmental Parts R & D Center, Korea Automotive Technology Instititute, Cheonan, 330–912, Korea
| | - Kyo Young Lee
- Department of Hospital Pathology, Kangnam St. Mary's Hospital, The Catholic University of Korea, Seoul 137–701, Korea
| | - Val Vallyathan
- Exposure Assessment Branch and Pathology and Physiology Research Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, USA
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