Aerosol inhalation of Mycobacterium vaccae ameliorates airway structural remodeling in chronic asthma mouse model.

Background: Airway remodeling is accepted to be a determining component within the natural history of asthma. Nebulized inhalation of Mycobacterium vaccae (M. vaccae) has a protective effect on asthmatic mice. However, little is known regarding the effect of M. vaccae on airway structural remodeling in asthmatic mice. The purpose of this study was to explore the effect and the underlying mechanism of M. vaccae aerosol inhalation on airway structural remodeling in an asthma mouse model. Methods: Chronic asthma mouse models were established by ovalbumin induction. The number of inflammatory cells in bronchoalveolar lavage fluid (BALF), pathological alterations in lung tissue, and levels of associated cytokines (IL-5, IL-13, TNF-α, and ovalbumin-specific immunoglobulin E [OVA-sIgE]) were all assessed after M. vaccae therapy. The relative expression of interleukin (IL)-1ß, tumor necrosis factor-alpha (TNF-α), nuclear factor kappa B (NF-κB), and Wnt1-induced signaling protein 1 (WISP1) mRNA were detected. Western blotting and immunohistochemistry detected the expression of Wnt/ß-catenin pathway-related proteins in lung tissue. Results: M. vaccae aerosol inhalation relieved airway inflammation, airway hyper-responsiveness, and airway remodeling. M. vaccae reduced the levels of IL-5, IL-13, TNF-α, and OVA-sIgE in and downregulated the expression of IL-1ß, TNF-α, NF-κB, and WISP1 mRNA in the pulmonary. In addition, M. vaccae inhibited the expression of ß-catenin, WISP1, and Wnt1 protein and upregulated the expression of glycogen synthase kinase-3beta (GSK-3ß). Conclusion: Nebulized inhalation of M. vaccae can reduce airway remodeling during asthma.

Transcriptomic Analysis Reveals a Link Between Hippo Signaling Pathway and Macrophages in Lungs of Mice with OVA-Induced Allergic Asthma.

PURPOSE: The Hippo signaling pathway participates in the restriction of cell proliferation and organ growth. Activated macrophages have been implicated in the pathogenesis of allergic asthma. Recent studies have shown that Hippo signaling pathway may also be involved in the regulation of asthma. However, the link between Hippo signaling pathway and macrophages in the context of allergic asthma has not been investigated. The purpose of this study was to explore the link between Hippo signaling pathway and macrophages using a mice model of OVA-induced allergic asthma. METHODS: Mice models of asthma were established. Lung tissues were collected from mice and pooled for mRNA sequencing and bioinformatics analysis. The relative mRNA expression of Hippo signalling pathway-related proteins Yap1, Lef1 and Ctgf was also measured. Double immunofluorescence staining was performed on lung tissues to evaluate macrophage marker F4/80 expression and Yap1/Lef1/Ctgf expression. RESULTS: Results of the RNA-Seq of lung tissues demonstrated that the Hippo signaling pathway was down-regulated in OVA-induced allergic asthma. Using the cytoHubba tool kits in Cytoscape, the following top 10 hub genes of Hippo signalling pathway were identified: Yap1, Lef1, Ctgf, Ccnd1, Axin2, Smad7, Wnt4, Wnt3a, Pard6b, and Wwc1. Using the seq-ImmuCC (http://218.4.234.74:3200/immune/), a negative correlation was found between macrophages and Hippo signaling pathway activity (R2 = 0.93). The mRNA expression levels of pulmonary Yap1, Lef1, and Ctgf were down-regulated in the mice model of OVA-induced allergic asthma. Moreover, double-stained immunofluorescence for F4/80 and Yap1, Lef1, Ctgf in mouse lung sections respectively revealed that macrophage proliferation was correlated with downregulation of the Hippo signaling pathway in the mice model of OVA-induced allergic asthma. CONCLUSION: These results demonstrated that the Hippo signaling pathway was down-regulated in asthma mice, and the proliferation of macrophages was associated with downregulation of the Hippo signaling pathway. These findings reveal novel insights into the pathogenesis and treatment of asthma.

IL-27 mediates anti-inflammatory effect in cigarette smoke induced emphysema by negatively regulating IFN-γ producing cytotoxic CD8+ T cells in mice.

Chronic airway inflammation mediated by CD8+ T lymphocytes contributes to the pathogenesis of Chronic obstructive pulmonary disease (COPD). Deciphering the fingerprint of the chronic inflammation orchestrated by CD8+ T cells may allow the development of novel approaches to COPD management. Here, the expression of IL-27 and IFN-γ+ CD8+ Tc1 cells were evaluated in patients with COPD and in cigarette smoke-exposed mice. The production of IL-27 by marrow-derived dendritic cells (mDCs) in response to cigarette smoke extract (CSE) was assessed. The role of IL-27 in IFN-γ+ CD8+ Tc1 cells was explored. We demonstrated that elevated IL-27 was accompanied by an exaggerated IFN-γ+ CD8+ Tc1 response in a smoking mouse model of emphysema. We noted that lung dendritic cells were one of the main sources of IL-27 during chronic cigarette smoke exposure. Moreover, CSE directly induced the production of IL-27 by mDCs in vitro. IL-27 negatively regulated the differentiation of IFN-γ+ CD8+ Tc1 cells isolated from cigarette smoke-exposed mice in a STAT1- and STAT3-independent manner. Systemic administration of recombinant IL-27 attenuated IFN-γ+ CD8+ Tc1 response in the late phase of cigarette smoke exposure. Our results uncovered that IL-27 negatively regulates IFN-γ+ CD8+ Tc1 response in the late stage of chronic cigarette smoke exposure, which may provide a new strategy for the anti-inflammatory treatment of smoking-related COPD/emphysema.

Effects of Mycobacterium vaccae Aerosol Inhalation on Airway Inflammation in Asthma Mouse Model.

Background:Mycobacterium vaccae vaccine, a composition of Mycobacterium proteins, has been known to have bidirectional immunomodulatory functions. Recent studies have shown that M. vaccae has a therapeutic potential for treating asthma. However, little is known regarding the effect of M. vaccae aerosol inhalation during allergen sensitization or challenge on asthma. The purpose of this study was to explore the effect and the underlying mechanism of M. vaccae aerosol inhalation during allergen sensitization or challenge on airway inflammation in an asthma mouse model. Methods: Asthma mouse models were established. Mice received aerosol inhalation with M. vaccae once daily during allergen sensitization or challenge for 5 days successively. Airway responsiveness, bronchoalveolar lavage fluid (BALF) cell count, histology, and cytokine concentrations (IL-4, IFN-γ, IL-10, and IL-17) were measured. The relative mRNA expression of ASC, caspase-1, TNF-α, and IL-1ß was also determined. Expression of pulmonary NLRP3 and nuclear factor kappa B (NF-κB) protein was measured using immunohistochemistry and Western blot. Results:M. vaccae aerosol inhalation suppressed airway hyperresponsiveness and inflammation, reduced levels of IL-4, upregulated expression of IFN-γ and IL-10 in BALF, inhibited mRNA expression of pulmonary ASC, caspase-1, TNF-α, and IL-1ß, and also inhibited expression of pulmonary NLRP3 and NF-κB protein during allergen sensitization or challenge. Conclusion:M. vaccae aerosol inhalation can suppress airway hyperresponsiveness and inflammation during allergen sensitization or challenge, and may be a promising approach for asthma therapy.

Mycobacterium vaccae Nebulization in the Treatment of COVID-19: A Randomized, Double-Blind, Placebo-Controlled Trial.

Background: Severe acute respiratory syndrome coronavirus 2 infection is associated with strong infectiousness and has no effective therapy. We aimed to explore the efficacy and safety of Mycobacterium vaccae nebulization in the treatment of Coronavirus Disease 2019 (COVID-19). Methods: In this randomized, double-blind, placebo-controlled clinical trial, we included 31 adult patients with moderate COVID-19 who were admitted to the Fourth People's Hospital of Nanning (Nanning, China) between January 22, 2020 and February 17, 2020. Patients were randomly divided into two groups: group A (standard care group) and group B (M. vaccae in combination with standard care group). The primary outcome was the time interval from admission to viral RNA negative conversion (oropharyngeal swabs were used in this study). Secondary outcomes included chest computed tomography (CT), mortality, length of hospital stay, complications during treatment, and so on. Patients were followed up to 4 weeks after discharge (reexamination of viral RNA, chest CT, etc.). Results: Nucleic acid test negative conversion time in group B was shorter than that in group A (2.9 days [2.7-8.7] vs. 6.8 days [3.3-13.8]; p = 0.045). No death and no conversion to severe or critical cases were observed in both groups. Two weeks after discharge, neither "relapse" nor "return to positive" cases were found. Four weeks after discharge, it was found that there was no case of " relapse " or "return to positive" in group B, and 1 patient in group A showed "return to positive", but there was no clinical manifestation and imaging progression. No adverse reactions related to M. vaccae were found during observation period. Conclusion:M. vaccae treatment might shorten the time interval from admission to viral RNA negative conversion, which might be beneficial to the prevention and treatment of COVID-19. Clinical Trial Registration: ChiCTR2000030016.

Afforestation suppresses Oncomelania hupensis snail density through influencing algae in beaches of the Dongting Lake.

BACKGROUND: Oncomelania snails serve as the sole intermediate host for Schistosoma japonicum, one of the most important neglected tropical diseases in the world. Afforestation suppression of the Oncomelania hupensis snail has been a long-term effective national strategy to decrease snail density in China. Many previous studies have made clear that vegetation (biotic factors) and soil (abiotic factors) were the basic requirements for snail survival on beaches. Moreover, a lot of research on snail control has been focused on the specific influencing environmental factors for snail survival, such as the vegetation community structure, species composition, diversity index, and the physical and chemical properties of the soil. Most of the existing research has studied the influence of a single factor on snail population density. Conversely, there have been only a few studies focused on the food sources and food composition of the snails. The current research situation on snail control has indicated that the mechanisms underlying ecological snail control have not been systematically characterized. The question of whether biotic or abiotic factors were more important in influencing snail survival remains unclear. Afforestation on beaches has significantly suppressed snail density in China so far. In this study, we proposed that the reduction of snail density was not affected by a single factor but by the interactions of multiple related factors introduced by afforestation. Moreover, different biotic and abiotic factors have significantly different effects on snail control. Therefore the goal of this study was to evaluate the relative importance and interactions of related biotic and abiotic factors on snail density. Methods: Four major vegetation communities: Sedge, Reed, Artificial poplar (3 years of age) and Artificial poplar (5 years of age), on the beaches of the Yangtze River in China were selected for vegetation and snail surveys, as well as for soil sampling. Structural Equation Model (SEM) analysis was used to assess the interactions of biotic and abiotic factors in the context of snail ecology. The soil properties were considered as abiotic factors, while algae of Chlorophyta, Cyanophyta and Bacillariophyta phyla were considered to be biotic factors. In the path analysis, the total effect between the variables was the sum of the direct and indirect effects. RESULTS: The snail density had significant correlations with soil properties, such as water content, bulk density, capillary porosity and pH value, as well as with all three types of soil algae, Chlorophyta, Cyanophyta, and Bacillariophyta. Snail density had a direct negative relationship with capillary porosity and soil bulk density, an indirect negative relationship with soil pH value and an indirect positive relationship with soil water content via soil algae. Meanwhile, as an important food source for the snail, the Chlorophyta, Cyanophyta and Bacillariophyta algae had a significant positive correlation with snail density. High soil pH had a negative impact on Chlorophyta, Bacillariophyta, while soil water content had a positive impact on Chlorophyta, and soil bulk density had a negative impact on Cyanophyta. In addition, the soil pH value and soil bulk density both had negative correlations with soil water content. CONCLUSION: Afforestation of the beach environment can significantly reduce the snail population density by altering ecological factors. Soil algae (biological factors) might be the key element that drives ecological snail control. As important habitat determinants, the impact of the properties of the soil (non-biological factors) on the snail population was largely mediated through soil algae.

Mycobacterium vaccae nebulization protects Balb/c mice against bronchial asthma through neural mechanisms.

OBJECTIVES: Bronchial asthma can be effectively controlled but not be cured, its etiology and pathogenesis are still unclear, and there are no effective preventive measures. The key characteristic of asthma is chronic airway inflammation, and recent research has found that airway neurogenic inflammation plays an important role in asthma. We previously found that Mycobacterium vaccae nebulization protects against asthma. Therefore, this objective of this study is to explore the effect of M. vaccae nebulization on asthmatic neural mechanisms. METHODS: A total 18 of female Balb/c mice were randomized into normal, asthma control, and M. vaccae nebulization (Neb.group) groups, and mice in the Neb.group were nebulized with M. vaccae one month before the asthmatic model was established. Then, 1 month later, the mice were sensitized and challenged with ovalbumin. Twenty-four hours after the last challenge, mouse airway responsiveness; pulmonary brain-derived neurotropic factor (BDNF), neurofilament-medium length (NF-M, using NF09 antibody), and acetylcholine expression; and nerve growth factor (NGF) mRNA level were determined. RESULTS: We found that the BDNF, NF09, acetylcholine expression, and NGF mRNA level were decreased in the Neb.group compared with levels in the asthma control group. CONCLUSION: M. vaccae nebulization may protected in Balb/c mice against bronchial asthma through neural mechanisms.

Regulation of γδT17 cells by Mycobacterium vaccae through interference with Notch/Jagged1 signaling pathway.

The objective of this study was to investigate the effect of Mycobacterium vaccae on Jagged 1 and gamma delta T17 (γδT17) cells in asthmatic mice. An asthma mouse model was established through immunization with ovalbumin (OVA). Gamma-secretase inhibitor (DAPT) was used to block the Notch signaling pathway. M. vaccae was used to treat asthma, and related indicators were measured. Blocking Notch signaling inhibited the production of γδT17 cells and secretion of cytokine interleukin (IL)-17, which was accompanied by a decrease in Jagged1 mRNA and protein expression in the treated asthma group compared with the untreated asthma group. Similarly, treatment with M. vaccae inhibited Jagged1 expression and γδT17 cell production, which was associated with decreased airway inflammation and reactivity. The Notch signaling pathway may play a role in the pathogenesis of asthma through the induction of Jagged1 receptor. On the other hand, the inhibitory effect of M. vaccae on Jagged1 receptor in γδT17 cells could be used for the prevention and treatment of asthma.

Inhalation of nebulized Mycobacterium vaccae can protect against allergic bronchial asthma in mice by regulating the TGF-ß/Smad signal transduction pathway.

BACKGROUND: Mycobacterium vaccae nebulization imparted protective effect against allergic asthma in a mouse model. The TGF-ß/Smad signal transduction pathway plays an important role in allergic bronchial asthma. However, the effect of M. vaccae nebulization on the TGF-ß/Smad signal transduction pathway in mouse models of allergic asthma remains unclear. This study investigated the preventive effect of M. vaccae nebulization during bronchial asthma in a mouse model and elucidate the implication of TGF-ß/Smad signal transduction pathway in the process. METHODS: In total, 24 female Balb/c mice were randomized to normal control (group A), asthma control (group B), and M. vaccae nebulization (group C) groups. Both groups B and C were sensitized using ovalbumin for establishment of the asthmatic model; group A received phosphate-buffered solution. Prior to the establishment of asthma, Group C was nebulized with M. vaccae. Airway responsiveness was measured in all the groups, using a noninvasive lung function machine before and 24 h after establishment of the asthmatic model. The animals were then harvested, and bronchoalveolar lavage fluid (BALF) and lung tissue were collected. The total cell counts in BALF was estimated. Protein expression of TGF-ß1, TßR1, Smad1, and Smad7 was detected by immunohistochemistry. The population of CD3 + γδT, IL-13 + CD3 + T, TGF-ß + CD3 + T, IL-13 + CD3 + γδT, and TGF-ß+ CD3+ γδT cells were detected by flow cytometry. One-way analysis of variance for within-group comparisons, the least significant difference t-test or Student-Newman-Keuls test for intergroup comparisons, and the nonparametric rank sum test for analysis of airway inflammation scores were used in the study. RESULTS: The eosinophil count; protein expression of TGF-ß1, TßR1, and Smad1; and percentages of CD3 + γδT and IL-13 + CD3 + T cells were significantly lower in the M. vaccae nebulization group than in the asthma control group (P < 0.01). There were significant intergroup differences in the percentages of TGF-ß + CD3 + T and IL-13 + CD3 + γδT cells (P < 0.05). CONCLUSIONS: Mycobacterium vaccae nebulization could confer protection against allergic bronchial asthma by reducing airway responsiveness and alleviating airway inflammation in mice. The underlying mechanism might be attributed its effect on the deregulated expression of TGF-ß1, TßR1, Smad1, and Smad7 of the TGF-ß/Smad signal transduction pathway.

One-Week Nebulization of Mycobacterium vaccae Can Protect Against Pulmonary Respiratory Syncytial Virus Infection in Balb/c Mice.

Background: Respiratory syncytial virus (RSV) infection is the most common cause of acute lower respiratory tract infection in children, leading to their death. Currently, no effective prevention and treatment methods for RSV infection are available. RSV and many other unknown viruses pose a serious threat to human health. Our previous study demonstrated that Mycobacterium vaccae nebulization can protect against allergic asthma. As RSV infection and asthma are closely related, we hypothesized that M. vaccae could protect against pulmonary RSV infection. Therefore, we evaluated the effect of M. vaccae on RSV infection in Balb/c mice. Methods: The mice were randomized into three groups: normal, RSV, and M. vaccae. One week before the RSV infection model was established, the mice in the M. vaccae group were nebulized with M. vaccae. On the fourth day after RSV infection, airway responsiveness, airway inflammation, pulmonary RSV infection, mRNA levels of pulmonary toll-like receptor (TLR) 7 and TLR8, and pulmonary NF09, acetylcholine, and epidermal growth factor regulator (EGFR) expression levels in all mice were measured. Results: The airway inflammation in the M. vaccae group was alleviated compared with that in the RSV group. In the M. vaccae group, the pulmonary mRNA level of RSV and the pulmonary expression levels of NF09, acetylcholine, and EGFR were decreased considerably, whereas the mRNA levels of TLR7 and TLR8 were increased significantly. Conclusions: One-week nebulization of M. vaccae can protect against RSV infection in Balb/c mice. The mechanism involves the regulation of neurotransmitters and expression of TLR7, TLR8, and EGFR.

Regulation of γδT17 cells by Mycobacterium vaccae through interference with Notch/Jagged1 signaling pathway

The objective of this study was to investigate the effect of Mycobacterium vaccae on Jagged 1 and gamma delta T17 (γδT17) cells in asthmatic mice. An asthma mouse model was established through immunization with ovalbumin (OVA). Gamma-secretase inhibitor (DAPT) was used to block the Notch signaling pathway. M. vaccae was used to treat asthma, and related indicators were measured. Blocking Notch signaling inhibited the production of γδT17 cells and secretion of cytokine interleukin (IL)-17, which was accompanied by a decrease in Jagged1 mRNA and protein expression in the treated asthma group compared with the untreated asthma group. Similarly, treatment with M. vaccae inhibited Jagged1 expression and γδT17 cell production, which was associated with decreased airway inflammation and reactivity. The Notch signaling pathway may play a role in the pathogenesis of asthma through the induction of Jagged1 receptor. On the other hand, the inhibitory effect of M. vaccae on Jagged1 receptor in γδT17 cells could be used for the prevention and treatment of asthma.

SWOT analysis on snail control measures applied in the national schistosomiasis control programme in the People's Republic of China.

BACKGROUND: Snail control is an important component in the national schistosomiasis control programme in China, by application of chemical molluscicides, forestry projects, agriculture projects and water conservancy projects in recent decades. However, there are still wide areas of snail inhabited in China which remains a great challenge to achieve the goal of schistosomiasis elimination by 2025. Therefore, a SWOT (strengths, weaknesses, opportunities and threats) analysis on snail control measures is required for precision schistosomiasis control. METHODS: The SWOT approach, which is a well-known structured analysis tool, was used to identify and evaluate the specific characteristics of four types of snail control measures in China, including chemical mollusciciding, forestry, agriculture, and water conservancy projects. The analysis were carried out based on the information collection from literature review, of research papers, books, annual report database of national schistosomiasis control programme in China, reports from the academic forums, and so on. RESULTS: For chemical mollusciciding, application strategy needs to focus on specific local settings, such as stage of schistosomiasis control, environmental factors, and limitations from external policies and internal deficiencies. Regarding forestry projects, the optimal strategies are to cooperate with other national forestry programmes to share the investment costs and pay attention on wetland protection. In agriculture projects, it is necessary to develop related cash crop industries and combine with national farmland consolidation projects simultaneously to increase the total economic benefits. Concerning water conservancy projects, the main purpose is to control snail migration from snail area to snail-free areas nationwide. CONCLUSIONS: Integrated strategies for various measures application and a top-level designed cooperation mechanism will be the necessary to eliminate snail and schistosomiasis in China.

[GIS platform for real-time monitoring and early warning of forestry schistosomiasis-control project: a case study in Renshou County, Sichuan Province].

OBJECTIVE: To real-timely monitor the environment in the forestry schistosomiasis control project (CFSCP) area and to early warn the status of Oncomelania hupensis snails in the schistosomiasis endemic area. METHODS: Based on ArcGIS Engine 10.1 software, the Geographic Information System (GIS) platform of the forestry schistosomiasis project of real-time monitoring, early warning and emergency management in Renshou County, Sichuan Province, was designed and established. RESULTS: The functions of the platform mainly included real-time monitoring of the environment in CFSCP area, and early warning of the crisis status of 0. hupensis snails, as well as editing the map of snail distribution, query, spatial analysis and other GIS functions. CONCLUSION: This platform could provide the scientific support to the forestry administrative department of the CFSCP area.

Obesity enhances Th2 inflammatory response via natural killer T cells in a murine model of allergic asthma.

BACKGROUND: Obesity increases the incidence of asthma, but mechanism between asthma and obesity isn't utterly understood. NKT cells are intermediary activist between the innate and adaptive immune. It may play an equally important role in both obesity and asthma. We studied an obese mouse model of allergic asthma to test whether NKT cells act as a linkage in the development of obesity with asthma. METHODS: Balb/c mice were divided into control group (A), asthma model group (B), the obesity group (C) and obesity with asthma group (D), asthma model made by OVA. Obesity was induced. AHR were measured; HE staining of lung was made; NKT cells were detected and IL-4 and IFN-γ concentration were determined. RESULTS: Lung histology showed airway inflammatory in obesity with asthma are significant than in asthma. IL-4 levels were increased compared with the control group. IFN-γ levels were decreased compared with the control group. More CD69+NKT cells of asthma group and obese asthma group correlated to the enhancement of airway inflammation and AHR. IFN-γ+NKT cells vary in different states not paralleling with CD69+NKT cells. CONCLUSION: The activity level of NKT cells in obesity with asthma mice enhances Th2 Inflammatory response by regulating IL-4 and IFN-γ secretion. The activation of NKT enhanced asthma TH2 inflammatory responce. NKT cells play an important role in the development of asthma in obesity.

[Mollusicidal effects of some species of plants in hilly and mountainous areas].

OBJECTIVE: To valuate the mollusicidal effects of some plants cultivated in the hilly and mountainous areas on Oncomelania hupensis and screen the plants against O. hupensis snails. METHODS: The mollusicidal effects of water extracts of plant materials were tested in laboratory. RESULT: The LC50 of all the species in 24 h, 48 h, and 120 h reached the middle noxious level against O. hupensis snails. According to the taxis of LC50(s) in 120 h, Eucalyptus camaldulensis was best with a LC50 of 0.013%, and Ailanthus altissima, Zanthoxylum bungeanum, Juglans regia, Melia azedarach, Nerium indicum, Pterocarva stenobtera, Cinnamomum camphora, Vetiveria zizanioides, and Citrus reticulata were the second with LC50 (s) between 0.020% and 0.370%, and Zingiber officinale had a lower effect on snail control with a LC50 of above 0.500%. There was a correlation between the death rate of snails and soak time. CONCLUSION: The resources of snail-restrained plants are very abundant, and four plants, such as Eucalyptus camaldulensis, Ailanthus altissima, Cinnamomum camphora, and Vetiveria zizanioides have some mollusicidal effect.

[Progress in researches on active constituents and molluscicidal activity of Sapium sebiferum].

Sapium sebiferum contains a variety of organic acids, flavonoids and phenolic substances, which were linked with the functions of poisoning Oncomelania. Sapium sebiferum is a good plant material of inhibiting Oncomelania. This paper reviews the variety, resources and active ingredients of Sapium sebiferum, and the researches of Sapium sebiferum inhibiting Oncomelania, and forecasts the development of Sapium sebiferum as an inhibiting Oncomelania forest in order to provide the evidence for its penetrating research and development.