transforming-growth-factor-beta and Haemophilus-Infections

Pneumonia, the most typical and frequent lower respiratory tract infection (LRTI), is a leading cause of health problems in the United States. Bacteria represent the most prevailing cause of pneumonia in both children and adults. Although pneumonia with a single bacterial infection is common, a significant portion of patients with pneumonia is polymicrobial. This infection is often complexed with other physiological factors such as cytokines and growth factors. Nontypeable Haemophilus influenzae (NTHi) is the most frequently recovered Gram-negative bacterial pathogen in the respiratory system and induces strong inflammatory responses. NTHi also synergizes with other respiratory pathogens, such as Streptococcus pneumoniae and respiratory viruses and pro-inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α). It is noteworthy that NTHi not only synergizes with growth factors such as transforming growth factor-beta (TGF-β), but also utilizes growth factor receptors such as TGF-β receptor and epidermal growth factor receptor (EGFR), to enhance inflammatory responses. Although appropriate inflammation is a protective response against invading pathogens, an uncontrolled inflammatory response is often detrimental to the host. Thus, inflammation must be tightly regulated. The human immune system has evolved strategies for controlling overactive inflammatory response. One such important mechanism is via regulation of negative feedback regulators for inflammation. CYLD, a multifunctional deubiquitinase, was originally reported as a tumor suppressor, but was recently identified as a negative regulator for nuclear factor-kappa B (NF-κB) signaling. It is induced by NTHi and TNF-α via a NF-κB-dependent mechanism, thereby serving as an inducible negative feedback regulator for tightly controlling inflammation in NTHi infection.

Topics: Animals; Deubiquitinating Enzyme CYLD; ErbB Receptors; Feedback, Physiological; Haemophilus Infections; Haemophilus influenzae; Humans; NF-kappa B; Pneumococcal Infections; Pneumonia, Bacterial; Respiratory System; Signal Transduction; Streptococcus pneumoniae; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha; Tumor Suppressor Proteins; Ubiquitin-Protein Ligases

Non-typeable

Topics: Aged; Bronchi; Cadherins; Cell Transdifferentiation; Cells, Cultured; Collagen Type IV; Female; Haemophilus Infections; Haemophilus influenzae; Humans; Male; Middle Aged; Pulmonary Disease, Chronic Obstructive; Respiratory Mucosa; Transforming Growth Factor beta; Up-Regulation; Vimentin

Nontypeable Haemophilus influenzae (NTHi) is associated with chronic otitis media (COM). In this study, we generated a murine model of COM by using eustachian tube (ET) obstruction and NTHi (10(7) CFU) inoculation into the tympanic bulla, and we investigated the relationship between regulatory T cells (Treg) and chronic inflammation in the middle ear. Middle ear effusions (MEEs) and middle ear mucosae (MEM) were collected at days 3 and 14 and at 1 and 2 months after inoculation. Untreated mice served as controls. MEEs were used for bacterial counts and to measure the concentrations of cytokines. MEM were collected for histological evaluation and flow cytometric analysis. Inflammation of the MEM was prolonged throughout this study, and the incidence of NTHi culture-positive MEE was 38% at 2 months after inoculation. The levels of interleukin-1β (IL-β), tumor necrosis factor alpha, IL-10, and transforming growth factor β were increased in the middle ear for up to 2 months after inoculation. CD4(+) CD25(+) FoxP3(+) Treg accumulated in the middle ear, and the percentage of Treg in the MEM increased for up to 2 months after inoculation. Treg depletion induced a 99.9% reduction of bacterial counts in MEEs and also significantly reduced the ratio of NTHi culture-positive MEE. The levels of these cytokines were also reduced in MEEs. In summary, we developed a murine model of COM, and our findings indicate that Treg confer infectious tolerance to NTHi in the middle ear.

Topics: Animals; Chronic Disease; Disease Models, Animal; Ear, Middle; Eustachian Tube; Haemophilus Infections; Haemophilus influenzae; Inflammation; Interleukin-10; Interleukin-1beta; Lymphocyte Count; Mice; Mice, Inbred BALB C; Mucous Membrane; Otitis Media with Effusion; T-Lymphocytes, Regulatory; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Granulation tissue is common in otitis media (OM), yet little is known about the signaling pathways in the formation of granulation tissue in response to infections. In this study, we sought to investigate the activation of the transforming growth factor beta (TGF-beta) signaling pathway in the formation of granulation tissue in response to middle ear pathogens.. Rat OM models were made by inoculating pneumococcus type 6A or nontypeable Haemophilus influenzae into the middle ear cavity or by obstructing the eustachian tube. Various pathway activities in the middle ear mucosa were analyzed with microarrays.. The TGF-beta signaling pathway was highly regulated in the middle ear cleft with bacterial OM, but not in the ears with eustachian tube obstruction. In ears with bacterial OM, the TGF-beta signaling pathway products were higher in Haemophilus-infected ears than in pneumococcus-infected ears.. Bacterial OM triggers granulation tissue to thrive in the middle ear cleft of rats. Nontypeable H influenzae is more potent than pneumococcus type 6A in the formation of granulation tissue. Eustachian tube obstruction alone did not contribute to granulation tissue formation in the middle ear.

Topics: Animals; Collagen; Down-Regulation; Ear, Middle; Epithelial Cells; Eustachian Tube; Fibroblasts; Fibronectins; Gene Expression Profiling; Granulation Tissue; Haemophilus Infections; Microarray Analysis; Models, Animal; Otitis Media; Pneumococcal Infections; Rats; Rats, Sprague-Dawley; Receptors, Transforming Growth Factor beta; Reverse Transcriptase Polymerase Chain Reaction; RNA; Signal Transduction; Smad Proteins, Receptor-Regulated; Transforming Growth Factor beta; Up-Regulation

alpha-Defensins, antimicrobial peptides produced mainly by neutrophils, have been reported to be associated with a wide variety of lung diseases, including idiopathic pulmonary fibrosis (IPF), cystic fibrosis (CF), and diffuse panbronchiolitis (DPB). In each disease, alpha-defensins are located in different areas, such as around the alveolar septa in IPF and around the airways in CF and DPB, suggesting that alpha-defensins play different roles. Meanwhile, growth factors are known to contribute to IPF, CF, and DPB. alpha-Defensins are known to induce interleukin (IL)-8 in airway epithelial cells, but the effects of alpha-defensins on the release of growth factors from various components in the lung have not been sufficiently investigated. In the present study, the in vitro effects of human neutrophil peptide (HNP)-1 (a subtype of alpha-defensin) on the expressions of IL-8 and growth factors in lung fibroblasts, bronchial epithelial cells, and alveolar epithelial cells were examined. HNP-1 mainly enhanced the expression of IL-8 in epithelial cells, whereas it enhanced transforming growth factor-beta and vascular endothelial growth factor expressions in lung fibroblasts. These results suggest that alpha-defensins play different roles in the pathogenesis of IPF, CF, and DPB according to the location in the lung where the alpha-defensins are mainly produced.

Topics: alpha-Defensins; Bronchiolitis; Cells, Cultured; Cystic Fibrosis; Epithelial Cells; Fibroblasts; Haemophilus Infections; Humans; Idiopathic Pulmonary Fibrosis; Interleukin-8; Lung; Transforming Growth Factor beta; Vascular Endothelial Growth Factors

Transforming growth factor-beta (TGF-beta) family members are multifunctional growth factors involved in regulating diverse biological processes. Despite the critical role for TGF-beta in regulating cell proliferation, differentiation, migration and development, its role in regulating NF-kappaB-dependent inflammatory response still remains unclear. Here, we show that TGF-beta1 induces acetylation of NF-kappaB p65 subunit to synergistically enhance bacterium nontypeable Haemophilus influenzae-induced NF-kappaB activation and inflammatory response in vitro and in vivo. The TGF-beta1-induced acetylation of p65 is mediated via a Smad3/4-PKA-p300-dependent signaling pathway. Acetylation of p65 at lysine 221 by TGF-beta1 is critical for synergistic enhancement of bacteria-induced DNA-binding activity, NF-kappaB activation, NF-kappaB-dependent transcription of TNF-alpha and IL-1beta and interstitial polymorphonuclear neutrophil infiltration in vitro and in vivo. These studies provide new insights into the novel regulation of NF-kappaB by TGF-beta signaling.

Topics: Acetylation; Blotting, Western; Chromatin Immunoprecipitation; Electrophoretic Mobility Shift Assay; Gene Expression Regulation; Haemophilus Infections; Haemophilus influenzae; HeLa Cells; Humans; Immunoprecipitation; Luciferases; Reverse Transcriptase Polymerase Chain Reaction; RNA Interference; Signal Transduction; Smad3 Protein; Transcription Factor RelA; Transforming Growth Factor beta

Streptococcus pneumoniae and Haemophilus influenzae are human pathogens that often asymptomatically colonize the mucosal surface of the upper respiratory tract, but also occasionally cause invasive disease. The ability of these species to traverse the epithelium of the airway mucosa was modeled in vitro using polarized respiratory epithelial cells in culture. Migration across the epithelial barrier was preceded by loss of transepithelial resistance. Membrane products of S. pneumoniae that included lipoteichoic acid induced disruption of the epithelial barrier in a Toll-like receptor 2-dependent manner. This result correlates with a recent genetic study that associates increased TLR2 signaling with increased rates of invasive pneumococcal disease in humans. Loss of transepithelial resistance by the TLR2 ligand correlated with activation of p38 MAP kinase and transforming growth factor (TGF)-beta signaling. Activation of p38 MAPK and TGF-beta signaling in epithelial cells upon nasal infection with S. pneumoniae was also demonstrated in vivo. Inhibition of either p38 MAPK or TGF-beta signaling was sufficient to inhibit the migration of S. pneumoniae or H. influenzae. Our data shows that diverse bacteria utilize common mechanisms, including MAPK and TGF-beta signaling pathways to disrupt epithelial barriers and promote invasion.

Topics: Animals; Caco-2 Cells; Cell Membrane; Cell Polarity; Epithelial Cells; Female; Haemophilus Infections; Haemophilus influenzae; Humans; Lipopolysaccharides; MAP Kinase Signaling System; Mice; Models, Biological; p38 Mitogen-Activated Protein Kinases; Pneumococcal Infections; Respiratory Mucosa; Streptococcus pneumoniae; Teichoic Acids; Toll-Like Receptor 2; Transforming Growth Factor beta

Acute otitis media (AOM) is the most common reason for outpatient antimicrobial therapy. Mixed infections pose a potential problem, since the first-line drug used for the treatment of AOM, amoxicillin, can be neutralized by beta-lactamase-producing pathogens of the upper respiratory tract. To study the effects of a 5-day course of amoxicillin on a mixed middle ear infection, rats were challenged with Streptococcus pneumoniae alone or in combination with beta-lactamase-producing nontypeable Haemophilus influenzae. Amoxicillin was introduced at the clinical peak of the infection. Local and systemic changes were monitored by otomicroscopy, bacterial culture, and analysis of histological changes and the expression of the transforming growth factor beta (TGF-beta) gene. beta-Lactamase-producing H. influenzae did not demonstrate an ability to protect S. pneumoniae. Amoxicillin eradicated the pneumococci in all treated animals but increased to some degree the ability of H. influenzae to persist at the site of infection. Thus, only an insignificant acceleration of the resolution of the AOM caused by a mixture of pathogens was observed during treatment. Moderate to major morphological changes could not be avoided by treatment of the mixed infections, but a slight downregulation of TGF-beta expression was observed. In contrast to infections caused by a single pathogen, the mixed infections induced white plaques in the tympanic membrane at a remarkably high frequency independent of treatment. These experimental findings constitute support for further studies of antimicrobial drugs and AOM caused by bacteria with and without mechanisms of antibiotic resistance.

Topics: Amoxicillin; Animals; beta-Lactamases; Culture Media; Ear, Middle; Haemophilus Infections; Haemophilus influenzae; Male; Otitis Media; Penicillins; Pneumococcal Infections; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction; Streptococcus pneumoniae; Transforming Growth Factor beta; Treatment Outcome

We investigated the functions of tonsillar mononuclear cells (TMC) regarding whether a Haemophilus parainfluenzae (HP) outer membranes antigen (HPOM) enhances IgA-related cytokine (IFN-gamma, IL-10. and TGF-beta) production in vitro by TMC in IgA nephropathy (IgAN) patients. In addition, we examined the effect of synthetic oligodeoxynucleotide and HPOM stimulation by TMC on IgA production, whether the constant region antisense to IgA inhibits the production of IgA in vitro by TMC. Eighteen patients with IgAN and 25 patients with chronic tonsillitis (CT) from 6 to 45 years (mean age of 20.9 years) participated in this study. TMC were obtained from resected tonsils, and total and HP-specific IgA levels, along with the concentration of TGF-beta, IL-10 and IFN-gamma in the supernatant of stimulated TMC were measured by ELISA. Isolated TMC were cultured with HPOM in the presence of 23 oligodeoxynucleotides (ODNs), and the induction of total IgA and HP-specific IgA in the supernatant was also measured using ELISA. To investigate the inhibition of IgA production, TMC were cultured with HPOM and antisence to IgA. We found that IgA-related cytokine (IFN-gamma, IL-10, and TGF-beta) production by unstimulated or stimulated TMC was higher in IgAN patients than CT patients. Two types of synthetic oligodeoxynucleotides produced higher HP-specific IgA than with HPOM stimulation alone. HPOM and antisence IgA inhibited the production of total IgA and HP-specific IgA in dose-depend manner. In conclusion, IFN-gamma, TGF-beta, and IL-10 influence each other in the pathogenesis of IgAN, and infection by not only HP but other bacteria or viruses which possess specific DNA sequences such as CpG motifs induce the production of HP-specific IgA by TMC.

Topics: Adolescent; Adult; Bacterial Outer Membrane Proteins; Cells, Cultured; Child; Female; Glomerulonephritis, IGA; Haemophilus Infections; Haemophilus influenzae; Humans; Immunoglobulin A; Interferon-gamma; Interleukin-10; Leukocytes, Mononuclear; Male; Middle Aged; Oligodeoxyribonucleotides, Antisense; Palatine Tonsil; Tonsillitis; Transforming Growth Factor beta

Acute otitis media (AOM) elicits potent inflammatory responses from the cells of the middle ear mucosa as well as from infiltrating leukocytes. To explore host responses during experimental AOM induced by Streptococcus pneumoniae type 3 and nontypeable Haemophilus influenzae (NTHi), otomicroscopy findings and expression of cytokine genes in the middle ear were monitored up to 1 month postinoculation. The mucosa and infiltrating cells responded rapidly to the bacterial challenge. Otomicroscopically, AOM appeared 1 day after NTHi inoculation and 3 days after pneumococcus inoculation. Pneumococcal AOM was more severe than NTHi otitis, but in general, lower transcript levels were detected in pneumococcus-infected than in NTHi-infected animals. Interleukin-6 (IL-6) mRNA levels peaked at 3 to 6 h for both pneumococcus-infected and NTHi-infected animals. IL-1alpha, tumor necrosis factor alpha, and IL-10 mRNA levels peaked at 6 h for NTHi otitis and 1 to 3 days for pneumococcal otitis. Comparing otomicroscopy with expression profiles, it would appear that the majority of cytokine mRNAs had passed their peak before the AOM diagnosis could be made clinically. Only transforming growth factor beta mRNA followed a slower time course, peaking very late and continuing expression even after the AOM was otomicroscopically resolved. IL-2 and IL-4 mRNAs were not detected in any animal at any time. Most of the investigated cytokines are very early markers for AOM and may be involved in initiation of inflammation, but they would be poor targets for pharmacological manipulation since their levels decline before clinical signs appear.

Topics: Acute Disease; Animals; Base Sequence; Cytokines; Disease Models, Animal; DNA Primers; Gene Expression; Haemophilus Infections; Haemophilus influenzae; Humans; Interleukins; Kinetics; Male; Otitis Media; Pneumococcal Infections; Rats; Rats, Sprague-Dawley; RNA, Messenger; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha