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Idiopathic pulmonary fibrosis (IPF) is a devastating lung disease with a median survival of 3 yr. IPF deteriorates upon viral or bacterial lung infection although pulmonary infection (pneumonia) in healthy lungs rarely induces fibrosis. Bacterial lipopolysaccharide (LPS) activates Toll like receptor 4 (TLR4) initiating proinflammatory pathways. As TLR4 has already been linked to hepatic fibrosis and scleroderma we now investigated the role of TLR4 in IPF fibroblasts. Lung tissue sections from patients with IPF were analyzed for TLR4 expression. Isolated normal human lung fibroblasts (NL FB) and IPF fibroblasts (IPF FB) were exposed to LPS and transforming growth factor ß (TGF ß) before expression analysis of receptors profibrotic mediators and cytokines. TLR4 is expressed in fibroblast foci of IPF lungs as well as in primary NL FB and IPF FB. As a model for a gram negative pneumonia in the nonfibrotic lung NL FB and IPF FB were coexposed to LPS and TGF ß. Whereas NL FB produced significantly less connective tissue growth factor upon costimulation compared with TGF ß stimulation alone IPF FB showed significantly increased profibrotic markers compared with control fibroblasts after costimulation. Although levels of antifibrotic prostaglandin E2 were elevated after costimulation they were not responsible for this effect. However significant downregulation of TGF ß receptor type 1 in control fibroblasts seems to contribute to the reduced profibrotic response in our in vitro model. Normal and IPF fibroblasts thus differ in their profibrotic response upon LPS induced TLR4 stimulation.

Emilie Seydoux,1,2Barbara Rothen-Rutishauser,1,3Izabela M Nita,1Sandor Balog,3Amiq Gazdhar,1Philip A Stumbles,4,5Alke Petri-Fink,3,6Fabian Blank,1,*Christophe von Garnier1,*1Department of Respiratory Medicine, Inselspital, Bern University Hospital, Department of Clinical Research, University of Bern, 2Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland; 3Adolphe Merkle Institute, University of Fribourg, Fribourg, Switzerland; 4School of Veterinary and Life Sciences, Molecular and Biomedical Sciences, Murdoch University,Perth, WA, Australia; 5Telethon Kids Institute, Perth, WA, Australia; 6Department of Chemistry, University of Fribourg, Fribourg, Switzerland*These authors contributed equally to the manuscriptIntroduction: Nanosized particles may enable therapeutic modulation of immune responses by targeting dendritic cell (DC) networks in accessible organs such as the lung. To date, however, the effects of nanoparticles on DC function and downstream immune responses remain poorly understood.Methods: Bone marrow–derived DCs (BMDCs) were exposed in vitro to 20or 1,000nm polystyrene (PS) particles. Particle uptake kinetics, cell surface marker expression, soluble protein antigen uptake and degradation, as well as in vitro CD4+ T-cell proliferation and cytokine production were analyzed by flow cytometry. In addition, co-localization of particles within the lysosomal compartment, lysosomal permeability, and endoplasmic reticulum stress were analyzed.Results: The frequency of PS particle–positive CD11c+/CD11b+ BMDCs reached an early plateau after 20minutes and was significantly higher for 20nm than for 1,000nm PS particles at all time-points analyzed. PS particles did not alter cell viability or modify expression of the surface markers CD11b, CD11c, MHC class II, CD40, and CD86. Although particle exposure did not modulate antigen uptake, 20nm PS particles decreased the capacity of BMDCs to degrade soluble antigen, without affecting their ability to induce antigen-specific CD4+ T-cell proliferation. Co-localization studies between PS particles and lysosomes using laser scanning confocal microscopy detected a significantly higher frequency of co-localized 20nm particles as compared with their 1,000nm counterparts. Neither size of PS particle caused lysosomal leakage, expression of endoplasmic reticulum stress gene markers, or changes in cytokines profiles.Conclusion: These data indicate that although supposedly inert PS nanoparticles did not induce DC activation or alteration in CD4+ T-cell stimulating capacity, 20nm (but not 1,000nm) PS particles may reduce antigen degradation through interference in the lysosomal compartment. These findings emphasize the importance of performing in-depth analysis of DC function when developing novel approaches for immune modulation with nanoparticles.Keywords: polystyrene particles, nanoparticles, immune modulation, mouse dendritic cells, CD4+ T-cells

A group of polysaccharides, called galactomannans I, were precipitated as their insoluble copper complexes from aqueous solutions of the crude polysaccharides obtained from each of the organisms designated in the title. The five galactomannans I were homogeneous under conditions of electrophoresis and ultracentrifugation and had high positive specific rotations. The major constituent monosaccharide was D-mannose; amounts of D-galactose ranged from nil for the polysaccharide from T. rubrum to 13% for that from T. schönleinii. Methylation and hydrolysis of the five galactomannans I yielded varying amounts of the following: 2,3,5,6-tetra-O-methyl-D-galactose (not present in the products from T. rubrum), 2,3,4,6-tetra-O-methyl-D-mannose, 2,3,4-tri-O-methyl-D-mannose, 2,4,6-tri-O-methyl-D-mannose, 3,4-di-O-methyl-D-mannose, and 3,5-di-O-methyl-D-mannose. Periodate oxidation results agreed with the methylation studies. The gross structural features of each galactomannan I appear to be the same, namely, a basic chain of 1 → 6 linked α-D-mannopyranose units for approximately every 22 of which there is a 1 → 3 linked α-D-mannopyranose residue. Branch points occur along the 1 → 6 linked chain at the C2 positions of the D-mannopyranose units and once in every 45 units at the C2 position of a 1 → 6 linked D-mannofuranose residue. The D-galactose in the polysaccharides is present exclusively as non-reducing terminal furanose units; non-reducing terminal units of D-mannopyranose are also present. The variations in the identities and relative amounts of the non-reducing terminal units were the only apparent differences in the gross structural features within this group of polysaccharides.

A simple and practical filter paper strip method for the in vitro assay of fungistatic agents (substances and ointments) has been described. The method involves a modified diffusion technique and can be applied to both water soluble and water insoluble compounds. It is sensitive, contamination is rare, and both pathogenic and nonpathogenic fungi can be used as test organisms. Several organisms can be tested simultaneously. The results are quantitative and reproducible.

Recent findings are reported about certain aspects of the structure and function of the mammalian and avian lungs that include(a) the architecture of the air capillaries (ACs) and the blood capillaries (BCs); (b) the pulmonary blood capillary circulatory dynamics; (c) the adaptive molecular, cellular, biochemical,compositional, and developmental characteristics of the surfactant system; (d) the mechanisms of the translocation of fine and ultra fine particles across the airway epithelial barrier; and (e) the particle-cell interactions in the pulmonary airways. In the lung of the Muscovy duck Cairina moschata, at least, the ACs are rotund structures that are interconnected by narrow cylindrical sections, while the BCs comprise segments that are almost as long as they are wide. In contrast to the mammalian pulmonary BCs, which are highly compliant, those of birds practically behave like rigid tubes. Diving pressure has been a very powerful directional selection force that has influenced phenotypic changes in surfactant composition and function in lungs of marine mammals. After nanosized particulates are deposited on the respiratory tract of healthy human subjects, some reach organs such as the brain with potentially serious health implications. Finally, in the mammalian lung, dendritic cells of the pulmonary airways are powerful agents in engulfing deposited particles, and in birds, macrophages and erythrocytes are ardent phagocytizing cellular agents. The morphology of the lung that allows it to perform different functions - including gas exchange, ventilation of the lung by being compliant, defense, and secretion of important pharmacological factors - is reflected in its "compromise design." Refereed/Peer-reviewed