Blocking IL-10 receptor signaling ameliorates Mycobacterium tuberculosis infection during influenza-induced exacerbation.

Epidemiological findings indicate that coinfection with influenza viruses is associated with an increased risk of death in patients suffering from tuberculosis but the underlying pathomechanisms are not well understood. In this study, we demonstrate that influenza A virus (IAV) coinfection rapidly impairs control of Mycobacterium tuberculosis (Mtb) in C57BL/6 mice. IAV coinfection was associated with significantly increased bacterial loads, reduced survival and a substantial modulation of innate and adaptive immune defenses including an impaired onset and development of Mtb-specific CD4+ T cell responses and the accumulation of macrophages with increased arginase-1 production in the lungs. Our findings strongly indicate that IAV coinfection compromises the host's ability to control Mtb infection via the production of IL-10 which was rapidly induced upon viral infection. The blockade of IL-10 receptor signaling reduced the bacterial load in coinfected mice to a level comparable with that in Mtb-only-infected animals. Taken together, our data suggest that IL-10 signaling constitutes a major pathway that enhances susceptibility to Mtb during concurrent IAV infection.

Software-aided quality control of parallel reaction monitoring based quantitation of lipid mediators.

We characterized the performance of a micro-flow LC-ESI-MS2 approach to analyze lipid mediators (LMs) and polyunsaturated fatty acids (PUFA) that was optimized for SPE free lipid extraction. Tandem mass spectrometry was exclusively performed in parallel reaction monitoring (PRM) mode using TOF and Orbitrap analyzers. This acquisition strategy allowed in addition to quantitation by specific quantifier ions to perform spectrum comparisons using full MS2 spectra information of the analyte. Consequently, we developed a dedicated software SpeCS that allows to 1) process raw peak lists, 2) generate customized spectral libraries, 3) test specificity of quantifier ions and 4) perform spectrum comparisons. The dedicated scoring algorithm is based on signal matching and Spearman's rank correlation of intensities of matched signal. The algorithm was evaluated in respect of its specificity to distinguish structural related LMs on both instrument platforms. We show how high resolution mass spectrometry is beneficial to distinguish co-eluted LM isomers and provide a generalized quality control procedure for PRM. The applicability of the approach was evaluated analyzing the lipid mediator response during M. tuberculosis infection in the mouse lung.

The Leukotriene B4 and its Receptor BLT1 Act as Critical Drivers of Neutrophil Recruitment in Murine Bullous Pemphigoid-Like Epidermolysis Bullosa Acquisita.

Recruitment of neutrophils and eosinophils into the skin is a hallmark of pemphigoid diseases. The molecular cues regulating granulocyte recruitment into the skin and the individual contributions of neutrophils and eosinophils to pemphigoid diseases are, however, poorly understood. The lipid mediator leukotriene B4 (LTB4) is a potent granulocyte chemoattractant and is abundant in the skin blister fluid of bullous pemphigoid (BP) patients, but its pathogenic significance is unknown. Using mouse models of BP-like epidermolysis bullosa acquisita and of BP, we show that LTB4 and its receptor BLT1 act as critical drivers of neutrophil entry into the skin upon antibody deposition at the dermal-epidermal junction. Mice deficient in 5-lipoxygenase, a key enzyme in LTB4 biosynthesis, or in BLT1 exhibited dramatic resistance to neutrophil recruitment and, consequently, skin inflammation. Accordingly, liquid chromatography-mass spectrometry, used to comprehensively profile lipid mediator generation in the first 48 hours after antibody deposition, showed a pronounced parallel increase in LTB4 and in neutrophils in the skin. Subsequent mechanistic studies in BP-like epidermolysis bullosa acquisita uncovered that neutrophils are necessary for skin inflammation, whereas eosinophils are dispensable, thus identifying neutrophils as major culprits of blister formation. Our results highlight LTB4/BLT1 as absolutely critical drivers of murine pemphigoid disease-like skin inflammation.

Generation and identification of anti-inflammatory peptides from bovine ß-casein using enzyme preparations from cod and hog.

BACKGROUND: The aim of the present study was to generate and identify potential anti-inflammatory peptides from bovine ß-casein with enzyme preparations from cod and hog. Furthermore, the potential of cod trypsin, derived from fishery by-products, to produce these bioactive peptides for replacement of non-food-grade tosyl phenylalanyl chloromethyl ketone (TPCK)-treated porcine trypsin enzyme preparation was evaluated. RESULTS: Potential anti-inflammatory peptides were obtained by hydrolysis of ß-casein with the tryptic enzyme preparations cod trypsin, porcine trypsin (TPCK-treated) and a porcine trypsin and chymotrypsin preparation (PTN 6.0 S). Proteolysates generated with enzyme preparations containing mainly chymotryptic activity (Cryotin, Cryotin F) did not exhibit any effect. CONCLUSION: The more chymotryptic enzyme activity is present, the lower is the potential anti-inflammatory activity of the hydrolysates in HEK(nfκb-RE) cells. Comparable peptides were produced by application of porcine trypsin (TPCK) and cod trypsin. Therefore, the enzyme preparation cod trypsin can replace the non-food-grade porcine enzyme preparation trypsin (TPCK) for the generation of potential anti-inflammatory peptides from ß-casein.

Antimonato polyoxovanadate based three-dimensional framework exhibiting ferromagnetic exchange interactions: synthesis, structural characterization, and magnetic investigation of {[Fe(C6H14N2)2]3[V15Sb6O42(H2O)]}·8H2O.

The new polyoxovanadate {[Fe(C6H14N2)2]3[V15Sb6O42(H2O)]}·8H2O (1) was obtained under solvothermal conditions using the amine that acts at the same time as the ligand, solvent, and reducing agent. The central structural motif of 1, [V15Sb6O42(H2O)](6-), is related to the {V18O42}-archetype cluster by replacing three VO5 square pyramids with three O2Sb-O-SbO2 moieties. Every [V15Sb6O42(H2O)](6-) cluster anion is expanded by six FeN4O2 octahedra, thus generating a rare three-dimensional network with differently sized pores hosting the crystal water molecules. In 1, two [V15Sb6O42(H2O)](6-) cluster anions with different orientations coexist. According to bond-valence-sum calculations, the anionic cluster can be formulated as [V(IV)15Sb(III)6O42(H2O)](6-), i.e., in line with the valence states of all other known {V15Sb6} clusters. The optical band gap of 1 was determined as 2.47 eV. Investigation of the magnetic behavior indicates dominating ferromagnetic exchange interactions between the V(4+) centers of the cluster and the Fe(2+) d(6) cations.

[V16Sb4O42(H2O){VO(C6H14N2)2}4]: a terminal expansion to a polyoxovanadate archetype.

The charge-neutral antimonatopolyoxovanadium(IV) cluster [V(IV)16Sb(III)4O42(H2O){V(IV)O(C6H14N2)2}4].10H2O.C6H14N2 was obtained under solvothermal conditions. The central cluster fragment, [V(IV) 16Sb(III)4O42], is a derivative of the [V18O42] archetype and is formed by replacing two VO5 polyhedra by two Sb2O5 units. The {V20Sb4} structure expands the {V16Sb4} motif by the addition of four square-pyramidal, terminal VO(1,2-diaminocyclohexane)2 groups. At low temperatures, the magnetic ground state is characterized by four independent S = 1/2 sites.