Background: CpG-oligonucleotides (CpG-ODN), which induce signaling through Toll-like receptor 9 (TLR9), are currently under investigation as adjuvants in therapy against infections and cancer. CpG-ODN function as Th-1 adjuvants and are able to activate dendritic cells. In humans TLR9 has been described to be strongly expressed in B-lymphocytes, monocytes, plasmacytoid dendritic cells and at low levels in human respiratory cells. We determined whether a direct interaction of bacterial DNA with the tumor cells themselves is possible and investigated the expression and function of TLR9 in human malignant solid tumors and cell lines. TLR9 expression by malignant tumor cells, would affect treatment approaches using CpG-ODN on the one hand, and, on the other hand, provide additional novel information about the role of tumor cells in tumor-immunology.

Backround: Cigarette smoke exposure including biologically active lipopolysaccharide (LPS) in the particulate phase of cigarette smoke induces activation of alveolar macrophages (AM) and alveolar epithelial cells leading to production of inflammatory mediators. This represents a crucial mechanism in the pathogenesis of chronic obstructive pulmonary disease (COPD). Respiratory pathogens are a major cause of exacerbations leading to recurrent cycles of injury and repair. The interaction between pathogen-associated molecular patterns and the host is mediated by pattern recognition receptors (PRR's). In the present study we characterized the expression of Toll-like receptor (TLR)-2, TLR4 and CD14 on human AM compared to autologous monocytes obtained from patients with COPD, healthy smokers and non-smokers. Methods:The study population consisted of 14 COPD patients without evidence for acute exacerbation, 10 healthy smokers and 17 healthy non-smokers stratified according to age. The expression of TLR2, TLR4 and CD14 surface molecules on human AM compared to autologous monocytes was assessed ex vivo using FACS analysis. In situ hybridization was performed on bronchoalveolar lavage (BAL) cells by application of the new developed HOPE-fixative. Results:The expression of TLR2, TLR4 and CD14 on AM from COPD patients, smokers and nonsmokers was reduced as compared to autologous monocytes. Comparing AM we detected a reduced expression of TLR2 in COPD patients and smokers. In addition TLR2 mRNA and protein expression was increased after LPS stimulation on non-smokers AM in contrast to smokers and COPD patients. Conclusion:Our data suggest a smoke related change in the phenotype of AM's and the cellular response to microbial stimulation which may be associated with impairment of host defenses in the lower respiratory tract. BackroundCOPD patients appear to have underlying pathologic abnormalities which facilitate bacterial colonisation and result in an increased rate of respiratory infections.

The introduction of electronic cigarettes has led to widespread discussion on the cardiovascular risks compared to conventional smoking. We therefore conducted a randomized cross-over study of the acute use of three tobacco products, including a control group using a nicotine-free liquid. Fifteen active smokers were studied during and after smoking either a cigarette or an electronic cigarette with or without nicotine (eGo-T CE4 vaporizer). Subjects were blinded to the nicotine content of the electronic cigarette and were followed up for 2 hours after smoking a cigarette or vaping an electronic cigarette. Peripheral and central blood pressures as well as parameters of arterial stiffness were measured by a Mobil-O-Graph® device. The peripheral systolic blood pressure rose significantly for approximately 45 minutes after vaping nicotine-containing liquid ( p<0.05) and for approximately 15 minutes after smoking a conventional cigarette ( p<0.01), whereas nicotine-free liquids did not lead to significant changes during the first hour of follow-up. Likewise, heart rate remained elevated approximately 45 minutes after vaping an electronic cigarette with nicotine-containing liquid and over the first 30 minutes after smoking a cigarette in contrast to controls. Elevation of pulse wave velocity was independent from mean arterial pressure as well as heart rate in the electronic cigarette and cigarette groups. In this first of its kind trial, we observed changes in peripheral and central blood pressure and also in pulse wave velocity after smoking a cigarette as well as after vaping a nicotine-containing electronic cigarette. These findings may be associated with an increased long-term cardiovascular risk.

Rationale Nontypeable Haemophilus influenzae (NTHi) is the most common cause for bacterial exacerbations in chronic obstructive pulmonary disease (COPD). Recent investigations suggest the participation of the inflammasome in the pathomechanism of airway inflammation. The inflammasome is a cytosolic protein complex important for early inflammatory responses, by processing Interleukin-1β (IL-1β) to its active form.ObjectivesSince inflammasome activation has been described for a variety of inflammatory diseases, we investigated whether this pathway plays a role in NTHi infection of the airways.MethodsA murine macrophage cell line (RAW 264.7), human alveolar macrophages and human lung tissue (HLT) were stimulated with viable or non-viable NTHi and/or nigericin, a potassium ionophore. Secreted cytokines were measured with ELISA and participating proteins detected via Western Blot or immunohistochemistry.Measurements and Main ResultsWestern Blot analysis of cells and immunohistochemistry of lung tissue detected the inflammasome key components NLRP3 and caspase-1 after stimulation, leading to a significant induction of IL-1β expression (RAW: control at the lower detection limit vs. NTHi 505±111pg/ml, p<0.01). Inhibition of caspase-1 in human lung tissue led to a significant reduction of IL-1β and IL-18 levels (IL-1β: NTHi 24 h 17423±3198pg/ml vs. NTHi+Z-YVAD-FMK 6961±1751pg/ml, p<0.01).ConclusionOur data demonstrate the upregulation of the NRLP3-inflammasome during NTHi-induced inflammation in respiratory cells and tissues. Our findings concerning caspase-1 dependent IL-1β release suggest a role for the inflammasome in respiratory tract infections with NTHi which may be relevant for the pathogenesis of bacterial exacerbations in COPD.