Inactivated influenza virus vaccine is efficient and reduces IL-4 and IL-6 in allergic asthma mice

Combining metabolomics with network pharmacology to reveal the therapeutic mechanism of Dingchuan Decoction in rats with OVA-induced allergic asthma

Dingchuan Decoction (DCD) is a traditional Chinese medicine prescription commonly used in the treatment of asthma, but the mechanism of DCD in treating asthma has not yet been determined. In this study, we employed a combination of metabolomics and network pharmacology to investigate the mechanism of DCD in treating asthma. An allergic asthma rat model was induced by ovalbumin (OVA). Metabolomics based on 1H NMR and UHPLC-MS was used to identify differential metabolites and obtain the major metabolic pathways and potential targets. Network pharmacology was utilized to explore potential targets of DCD for asthma treatment. Finally, the results of metabolomics and network pharmacology were integrated to obtain the key targets and metabolic pathways of DCD for the therapy of asthma, and molecular docking was utilized to validate the key targets. A total of 76 important metabolites and 231 potential targets were identified through metabolomics. Using network pharmacology, 184 potential therapeutic targets were obtained. These 184 targets were overlaid with the 231 potential targets obtained through metabolomics and were analyzed in conjunction with metabolic pathways. Ultimately, the key targets were identified as aldehyde dehydrogenase 2 (ALDH2) and amine oxidase copper-containing 3 (AOC3), and the relevant metabolic pathways affected were glycolysis and gluconeogenesis as well as arginine and proline metabolism. Molecular docking showed that the key targets had high affinity with the relevant active ingredients in DCD, which further demonstrated that DCD may exert therapeutic effects by acting on the key targets. The present study demonstrated that DCD can alleviate OVA-induced allergic asthma and that DCD may have a therapeutic effect by regulating intestinal flora and polyamine metabolism through its effects on ALDH2 and AOC3.

Screening of Bioactive Fraction of Radix Paeoniae Alba and Enhancing Anti-Allergic Asthma by Stir-Frying Through Regulating PI3K/AKT Signaling Pathway

Allergic asthma is a common respiratory inflammation disease. The crude Radix Paeoniae Alba (RPA) and its processed products have been used frequently as antipyretic and anti-inflammatory agents in traditional medicine. To evaluate the effect of honey and bran processing, different fractions of RPA were used for treating anti-allergic asthma in the ovalbumin (OVA)-induced mice model, and then, the most effective fraction of RPA and stir-frying Radix Paeoniae Alba with honey and bran (FRPA) for treating anti-allergic asthma were compared mutually for pharmacological effects. The results showed that the treatment of the dichloromethane fraction of RPA significantly improved the pathological condition of lung tissues, decreased the number of eosinophils and other cells in bronchoalveolar lavage fluid (BALF), and the increased the expression of various inflammatory factors. Furthermore, the study discovered that the lung pathological conditions, compared with the high dose of dichloromethane RPA fraction, could be ameliorated by high dose of dichloromethane FRPA fraction treatment. Moreover, the expression of inflammatory factors and the phosphorylation of the PI3K/AKT signaling pathway could be diminished by FRPA. Finally, the contents of compounds with a significant difference in the FRPA dichloromethane fraction were paeoniflorin, ethyl gallate, pentagalloylglucose, galloylpaeoniflorin, and others by UPLC/Q-TOF-MS analysis. These findings suggest that the dichloromethane fraction of FRPA has an enhancement effect on anti-allergic asthma and provide the experimental basis for exploring the processed mechanism of RPA.

Influenza in High-Risk Hosts-Lessons Learned from Animal Models

Factoring significantly into the global burden of influenza disease are high-risk populations that suffer the bulk of infections. Classically, the very young, very old, and pregnant women have been identified as high-risk populations; however, recent research has uncovered several other conditions that contribute to severe infection. By using varied animal models, researchers have identified molecular mechanisms underpinning the increased likelihood for infection due to obesity and malnourishment, as well as insight into the role sex hormones play in antiviral immunity in males, in females, and across the life span. Additionally, novel comorbidity models have helped elucidate the role of chronic infectious and genetic diseases in influenza virus pathogenesis. Animal models play a vital role in understanding the contribution of host factors to influenza severity and immunity. An in-depth understanding of these host factors represents an important step in reducing the burden of influenza among the growing number of people living with one or more chronic medical conditions.

Association between influenza vaccination and reduced risks of major adverse cardiovascular events in elderly patients

BACKGROUND

This study was conducted to determine the protective effect of influenza vaccine against primary major adverse cardiovascular events (MACEs) in elderly patients, especially those with influenza-like illness (ILI).

METHODS

This retrospective, population-based case-control study of an elderly population (age≥65 years) was conducted using Taiwan's National Health Insurance Research Database (2000-2013). One control was selected for each MACE case (n=80,363 each), matched according to age, year of study entry, and predisposing factors for MACEs. ILI and MACEs (myocardial infarction [MI] and ischemic stroke) were defined according to the International Classification of Diseases, Ninth Revision, Clinical Modification. Odds ratios (ORs) were calculated for the association between MACEs and vaccination.

RESULTS

Influenza vaccination received in the previous year was associated with reduced risks of primary MACEs overall (adjusted OR [aOR] 0.80, 95% CI 0.78-0.82, P<.001), MI (aOR 0.80, 95% CI 0.76-0.84, P<.001), and ischemic stroke (aOR 0.80, 95% CI 0.77-0.82, P<.001). ILI diagnosed in the previous year was associated with increased risks of MACEs (aOR 1.24, 95% CI 1.18-1.29, P<.001), MI (aOR 1.46, 95% CI 1.34-1.59, P<.001), and ischemic stroke (aOR 1.16, 95% CI 1.10-1.22, P<.001). Vaccination attenuated the heightened risks associated with ILI (MACEs: aOR 0.99, 95% CI 0.92-1.07, P=.834; MI: aOR 1.05, 95% CI 0.92-1.21, P=.440; ischemic stroke: aOR 0.96, 95% CI 0.89-1.05, P=.398).

CONCLUSIONS

Results of this study suggest that influenza vaccination is associated with reduced primary MACE risks in the elderly population, including those with ILI.

An Adenovirus-Vectored Influenza Vaccine Induces Durable Cross-Protective Hemagglutinin Stalk Antibody Responses in Mice

Currently licensed vaccines against the influenza A virus (IAV) need to be updated annually to match the constantly evolving antigenicity of the influenza virus glycoproteins, hemagglutinin (HA), and neuramidiase (NA). Attempts to develop universal vaccines that provide broad protection have resulted in some success. Herein, we have shown that a replication-deficient adenovirus expressing H5/M2e induced significant humoral immunity against the conserved HA stalk. Compared to the humoral responses induced by an inactivated influenza vaccine, the humoral responses induced by the adenovirus-vectored vaccine against the conserved stalk domain mediated cross-protection against heterosubtypic influenza viruses. Importantly, virus inactivation by formaldehyde significantly reduced the binding of monoclonal antibodies (mAbs) to the conserved nucleoprotein (NP), M2e, and HA stalk. These results suggest that inactivation by formaldehyde significantly alters the antigenicity of the HA stalk, and suggest that the conformation of the intact HA stalk provided by vector-based vaccines is important for induction of HA stalk-binding Abs. Our study provides insight into the mechanism by which a vector-based vaccine induces broad protection by stimulation of cross-protective Abs targeting conserved domains of viral proteins. The findings support further strategies to develop a vectored vaccine as a universal influenza vaccine for the control of influenza epidemics and unpredicted pandemics.

MAIT cells are activated during human viral infections

Mucosal-associated invariant T (MAIT) cells are abundant in humans and recognize bacterial ligands. Here, we demonstrate that MAIT cells are also activated during human viral infections in vivo. MAIT cells activation was observed during infection with dengue virus, hepatitis C virus and influenza virus. This activation—driving cytokine release and Granzyme B upregulation—is TCR-independent but dependent on IL-18 in synergy with IL-12, IL-15 and/or interferon-α/β. IL-18 levels and MAIT cell activation correlate with disease severity in acute dengue infection. Furthermore, HCV treatment with interferon-α leads to specific MAIT cell activation in vivo in parallel with an enhanced therapeutic response. Moreover, TCR-independent activation of MAIT cells leads to a reduction of HCV replication in vitro mediated by IFN-γ. Together these data demonstrate MAIT cells are activated following viral infections, and suggest a potential role in both host defence and immunopathology.

Mucosal Associated Invariant T cells have been implicated in response to bacterial pathogens. Here the authors show that in human viral infections, these cells are activated by IL-18 in cooperation with other pro-inflammatory cytokines, producing interferon gamma and granzyme B.

Inactivated influenza virus vaccine is efficient and reduces IL-4 and IL-6 in allergic asthma mice

Background

Allergic asthma is a globally respiratory inflammatory disease. Influenza virus is a respiratory pathogen that causes yearly epidemics and results in high rates of morbidity and mortality. Patients with allergic asthma had a more severe symptom and a higher mortality when they were infected with influenza virus. Hence, influenza vaccination is recommended for patients with asthma.

Objectives

We evaluated the efficacy and effects of influenza vaccination on allergic asthma in a mouse model.

Methods

Ovalbumin‐immunized mice were inoculated with inactivated influenza virus A/Puerto Rico/8/34 (PR8) as vaccines and morbidity or mortality and allergic asthma features of these mice were analyzed.

Results

Mice inoculated with inactivated PR8 induced high levels of anti‐PR8 IgG2a and upregulation of Toll‐like receptor (TLR) 7. Vaccinated allergic mice were healthy when they were challenged with live influenza virus while none of non‐vaccinated allergic mice survived. Furthermore, inactivated influenza virus vaccine induced neither extra airway inflammation nor asthma features such as IgE, airway hyper‐reactivity, and eosinophilia in allergic mice. Particularly, decreased frequency of immune cell infiltrated airways and Th2 cytokines IL‐4 and IL‐6 production in the bronchoalveolar lavage fluid were noted in vaccinated allergic mice. These results suggested that inactivated influenza virus vaccine is efficient to protect allergic mice from further influenza infection, and it does not exacerbate but reduces IL‐4 and IL‐6 of allergic asthma.

Conclusion

Influenza vaccination is essential and efficient for allergic subjects to protect influenza virus infection.