Synergistic effect of Dermatophagoides pteronyssinus allergen and Escherichia coli lipopolysaccharide on human blood cells

Inactivation of microorganisms on fabrics using plasma-activated nebulized mist driven by different plasma gases

The disinfection of fabrics is crucial in preventing the spread of infectious diseases caused by pathogenic microorganisms to maintain public health. A previous study proved that plasma-activated nebulized mist (PANM) could effectively inactivate microorganisms both in aerosol and attached to the surface. In this study, the PANM driven by different plasma gases were employed to inactivate microorganisms on diverse fabrics. The PANM could efficiently inactivate a variety of microorganisms, including bacteria, fungi, and viruses, contaminating different fabrics, and even across covering layers of different fabrics. The mites residing on the cotton fabrics both uncovered and covered with various types of fabrics were also effectively inactivated by the PANM. After 30 times repeated treatments of the PANM, notable changes were observed in the color of several fabrics while the structural integrity and mechanical strength of the fabrics were unaffected and maintained similarly to the untreated fabrics with slight changes in elemental composition. Additionally, only trace amounts of nitrate remained in the fabrics after the PANM treatment. Therefore, the PANM treatment supplied an efficient, broad-spectrum, and environmentally friendly strategy for industrial and household disinfection of fabrics.

Co-Activation of Human Whole Blood Cells with Lipopolysaccharides and an Allergen

The investigation of common inflammation mechanisms caused by exogenic compounds of microbial origin and allergens is one of the most important tasks in current biomedical science. The main manifestations of immune cell activation caused by pro-inflammatory agents are changes in receptor quantity on the surface of immune cells and the production of cytokines and chemokines by blood cells. The levels of expression of TLR4, CD14, and CD11b in the monocytes and neutrophils of human whole blood in response to LPS E. coli, Der p 2 allergen, or their combination reflect different functional activities in these cells, while the composition and amount of produced cytokines reflect the biological activity of the studied agonists. The activity of Der p 2 allergen in ex vivo experiments on whole blood samples is significantly lower compared with its activity in vitro in isolated PBMC cells, which should be taken into account when transferring the results obtained for isolated cells to whole blood cells. LPS R. capsulatus PG significantly decreases the synthesis of MyD88-dependent NF-κB-regulated cytokines activated by LPS E. coli, Der p 2, or their combination. This indirectly indicates the general mechanisms of cell activation caused by these structures and the unified mechanism of the protective action of LPS R. capsulatus PG against both endotoxin and a combination of endotoxin and the allergen.

The Allergenic Activity of Blo t 2, a Blomia tropicalis IgE-Binding Molecule

Only few allergens derived from house dust mite (HDM) species have been evaluated in terms of their potential to induce allergic inflammation. In this study, we aimed to evaluate different aspects of the allergenicity and allergenic activity of Blo t 2, a Blomia tropicalis allergen. Blo t 2 was produced as a recombinant protein in Escherichia coli. Its allergenic activity was tested in humans by skin prick test and basophil activation assays, and in mice, by passive cutaneous anaphylaxis and a model of allergic airway inflammation. Sensitization rate to Blo t 2 (54.3%) was similar to that found to Blo t 21 (57.2%) and higher than to Der p 2 (37.5%). Most Blo t 2-sensitized patients showed a low intensity response (99.5%). Blo t 2 elicited CD203c upregulation and allergen induced skin inflammation. Additionally, immunized animals produced anti-Blo t 2 IgE antibodies and passive transfer of their serum to non-immunized animals induced skin inflammation after allergen exposure. Immunized animals developed bronchial hyperreactivity and a strong inflammatory lung reaction (eosinophils and neutrophils). These results confirm the allergenic activity of Blo t 2 and supports its clinical relevance.

Participation of MAPK and PI3K in Regulation of Cytokine Secretion by Peripheral Blood Monocular Cells in Response to Escherichia coli LPS and rDer p 2 Combination

Search for the effective approaches to treat acute inflammation caused by combination of allergens and infectious agents is an important task for public health worldwide. House dust mites Dermatophagoides pteronyssinus are the source of allergens of the Der p groups and of microbial compounds, in particular, lipopolysaccharides (LPS). LPS and Der p 2 induce secretion of pro-inflammatory cytokines via activation of kinases p38 MAPK, MEK1/2, and PI3K. Participation of these kinases in the regulation of cells response to combined exposure to LPS and Der p 2 has not been sufficiently studied. We studied the effects of kinases (p38 MAPK, MEK1/2, and PI3K) inhibition on secretion of cytokines (TNF, IL-8, and IL-6) by peripheral blood mononuclear cells (PBMC) of healthy volunteers in response to E. coli LPS and rDer p 2. Contribution of kinases to the regulation of cell response to different agents (rDer p 2 and/or LPS) was revealed. It was found that p38 MAPK plays a key role in the regulation of secretion TNF by PBMC in response to the combination of LPS and rDer p 2. MEK1/2-dependent signaling is the main pathway for the synthesis of TNF and IL-8 in response to LPS and rDer p 2. PI3K-dependent signaling negatively regulates TNF production during rDer p 2-induced cell activation, but is not involved in the response to the combination of LPS and rDer p 2. PI3K-dependent signaling in the regulation of PBMC cytokine synthesis is most pronounced in response to their activation by rDer p 2. Understanding the mechanisms of immune cell responses to combinations of inflammatory agents could facilitate the search for new intracellular targets for anti-inflammatory therapy.

Systematic Characterization of the Group 2 House Dust Mite Allergen in Dermatophagoides microceras

Background

Allergic asthma, a chronic airway inflammatory disease, is a critical public health problem. Indoor house dust mites (HDMs) could cause allergic asthma. The prevalence of sensitization to Dermatophagoides microceras (Der m) was approximately 80% and is related to the immunoglobulin E crossing-reactivity of mites belonging to the same genus, Dermatophagoides pteronyssinus (Der p) and Dermatophagoides farina (Der f). However, studies on Der m are scant.

Methods

We used integrated OMICs approaches to identify and characterize the group 2 mite allergen-like protein in Der m (Der m 2). We established a Der m 2-induced allergic asthma mouse model and treated the mice with a fungal immunomodulatory protein (FIP-fve) isolated from Flammulina veluptipes to evaluate the allergenicity of Der m 2 and the immunomodulatory effects of FIP-fve.

Results

By performing de novo draft genome assembly and comparative genome analysis, we identified the putative 144-amino acid Der m 2 in silico and further confirmed its existence through liquid chromatography–tandem mass spectrometry. Der m 2 is a lipopolysaccharides (LPS)-binding protein. Thus, we examined the LPS-binding activity of recombinant Der m 2 by performing molecular docking analysis, co-immunoprecipitation (Co-IP), and a pull-down assay. Der m 2 elicited the production of pro-inflammatory cytokines, interleukin (IL)-6, and IL-8 in BEAS-2B cells, a human bronchial epithelial cell line, and induced airway hyperresponsiveness in mice. Furthermore, in mice sensitized with Der m 2, the administration of FIP-fve in either the earlier stage or the late stage, FIP-fve alleviated allergic asthma by moderating airway inflammation and remodeling.

Conclusions

Der m 2 induced inflammatory responses in cell and mouse models. FIP-fve alleviated inflammation in Der m 2-induced asthma in mice by exerting an immunomodulatory effect.