Ambroxol Treatment Suppresses the Proliferation of Chlamydia pneumoniae in Murine Lungs.

Ambroxol (Ax) is used as a mucolytics in the treatment of respiratory tract infections. Ax, at a general dose for humans, does not alter Chlamydia pneumoniae growth in mice. Therefore, we aimed to investigate the potential anti-chlamydial effect of Ax at a concentration four timed higher than that used in human medicine. Mice were infected with C. pneumoniae and 5-mg/kg Ax was administered orally. The number of recoverable C. pneumoniae inclusion-forming units (IFUs) in Ax-treated mice was significantly lower than that in untreated mice. mRNA expression levels of several cytokines, including interleukin 12 (IL-12), IL-23, IL-17F, interferon gamma (IFN-γ), and surfactant protein (SP)-A, increased in infected mice treated with Ax. The IFN-γ protein expression levels were also significantly higher in infected and Ax-treated mice. Furthermore, the in vitro results suggested that the ERK 1/2 activity was decreased, which is essential for the C. pneumoniae replication. SP-A and SP-D treatments significantly decreased the number of viable C. pneumoniae IFUs and significantly increased the attachment of C. pneumoniae to macrophage cells. Based on our results, a dose of 5 mg/kg of Ax exhibited an anti-chlamydial effect in mice, probably an immunomodulating effect, and may be used as supporting drug in respiratory infections caused by C. pneumoniae.

Azithromycin-liposomes as a novel approach for localized therapy of cervicovaginal bacterial infections.

BACKGROUND: Efficient localized cervicovaginal antibacterial therapy, enabling the delivery of antibiotic to the site of action at lower doses while escaping systemic drug effects and reducing the risk of developing microbial resistance, is attracting considerable attention. Liposomes have been shown to allow sustained drug release into vaginal mucosa and improve delivery of antibiotics to bacterial cells and biofilms. Azithromycin (AZI), a potent broad-spectrum macrolide antibiotic, has not yet been investigated for localized therapy of cervicovaginal infections, although it is administered orally for the treatment of sexually transmitted diseases. Encapsulation of AZI in liposomes could improve its solubility, antibacterial activity, and allow the prolonged drug release in the cervicovaginal tissue, while avoiding systemic side effects. PURPOSE: The objective of this study was to develop AZI-liposomes and explore their potentials for treating cervicovaginal infections. METHODS: AZI-liposomes that differed in bilayer elasticity/rigidity and surface charge were prepared and evaluated under simulated cervicovaginal conditions to yield optimized liposomes, which were assessed for antibacterial activity against several planktonic and biofilm-forming Escherichia coli strains and intracellular Chlamydia trachomatis, ex vivo AZI vaginal deposition/penetration, and in vitro cytotoxicity toward cervical cells. RESULTS: Negatively charged liposomes with rigid bilayers (CL-3), propylene glycol liposomes (PGL-2) and deformable propylene glycol liposomes (DPGL-2) were efficient against planktonic E. coli ATCC 700928 and K-12. CL-3 was superior for preventing the formation of E. coli ATCC 700928 and K-12 biofilms, with IC50 values (concentrations that inhibit biofilm viability by 50%) up to 8-fold lower than those of the control (free AZI). DPGL-2 was the most promising for eradication of already formed E. coli biofilms and for treating C. trachomatis infections. All AZI-liposomes were biocompatible with cervical cells and improved localization of the drug inside vaginal tissue compared with the control. CONCLUSION: The performed studies confirm the potentials of AZI-liposomes for localized cervicovaginal therapy.

Chlamydia pneumoniae Infection Exacerbates Atherosclerosis in ApoB100only/LDLR-/- Mouse Strain.

AIMS: Hyperlipidaemia model animals have been used to elucidate the role of Chlamydia pneumoniae (Cpn) infection in atherosclerosis. The aims of this study were to investigate the proatherogenic effect of multiple Cpn infections in ApoB100only/LDLR-/- mice which based on lipid profile can be regarded as the most suitable mouse model of human hypercholesterolemia and to compare the lesion development to that in a major atherosclerosis model ApoE-/- mice. METHODS AND RESULTS: Aorta samples of ApoB100only/LDLR-/- mice infected three times with Cpn were subjected to morphometric analyses. Morphometric evaluation disclosed that Cpn infections exacerbated atherosclerosis development in the aortic root and descending aorta of the mice fed with normal diet. Viable Cpn was detected in the ascending aorta by RT-PCR. Chlamydial 16SrRNA expression showed the presence of viable Cpn in the aorta of infected animals. A similar rate of acceleration of atherosclerosis was observed when the infection protocol was applied in ApoB100only/LDLR-/- and in ApoE-/- mice. CONCLUSION: Similar to ApoE-/- mice, ApoB100only/LDLR-/- mice with more human-relevant serum lipoprotein composition develop increased atherosclerosis after Cpn infections; thus this mouse strain can be used as a model of infection-related atherosclerosis enhancement and can provide further evidence for the proatherogenic influence of Cpn in mice.

Chryseobacterium gleum - a novel bacterium species detected in neonatal respiratory tract infections.

We report three patients with early neonatal infections. All patients had respiratory tract involvement with increased inflammation markers. Chryseobacterium gleum was cultured from the stomach content aspirated on arrival at the Neonatal intensive Care Unit and it was identified with the help of a Microflex™ MALDI Biotyper mass spectrometer (Bruker-Daltonik, Fremont, CA). Recovery could be achieved with ciprofloxacin treatment. We consider our cases a possible new clinical presentation of a rare human pathogen.

Construction of a highly flexible and comprehensive gene collection representing the ORFeome of the human pathogen Chlamydia pneumoniae.

BACKGROUND: The Gram-negative bacterium Chlamydia pneumoniae (Cpn) is the leading intracellular human pathogen responsible for respiratory infections such as pneumonia and bronchitis. Basic and applied research in pathogen biology, especially the elaboration of new mechanism-based anti-pathogen strategies, target discovery and drug development, rely heavily on the availability of the entire set of pathogen open reading frames, the ORFeome. The ORFeome of Cpn will enable genome- and proteome-wide systematic analysis of Cpn, which will improve our understanding of the molecular networks and mechanisms underlying and governing its pathogenesis. RESULTS: Here we report the construction of a comprehensive gene collection covering 98.5% of the 1052 predicted and verified ORFs of Cpn (Chlamydia pneumoniae strain CWL029) in Gateway(®) 'entry' vectors. Based on genomic DNA isolated from the vascular chlamydial strain CV-6, we constructed an ORFeome library that contains 869 unique Gateway(®) entry clones (83% coverage) and an additional 168 PCR-verified 'pooled' entry clones, reaching an overall coverage of ~98.5% of the predicted CWL029 ORFs. The high quality of the ORFeome library was verified by PCR-gel electrophoresis and DNA sequencing, and its functionality was demonstrated by expressing panels of recombinant proteins in Escherichia coli and by genome-wide protein interaction analysis for a test set of three Cpn virulence factors in a yeast 2-hybrid system. The ORFeome is available in different configurations of resource stocks, PCR-products, purified plasmid DNA, and living cultures of E. coli harboring the desired entry clone or pooled entry clones. All resources are available in 96-well microtiterplates. CONCLUSION: This first ORFeome library for Cpn provides an essential new tool for this important pathogen. The high coverage of entry clones will enable a systems biology approach for Cpn or host-pathogen analysis. The high yield of recombinant proteins and the promising interactors for Cpn virulence factors described here demonstrate the possibilities for proteome-wide studies.