TCR Transgenic Mice: A Valuable Tool for Studying Viral Immunopathogenesis Mechanisms.

Viral infectious diseases are a significant burden on public health and the global economy, and new viral threats emerge continuously. Since CD4+ and CD8+ T cell responses are essential to eliminating viruses, it is important to understand the underlying mechanisms of anti-viral T cell-mediated immunopathogenesis during viral infections. Remarkable progress in transgenic (Tg) techniques has enabled scientists to more readily understand the mechanisms of viral pathogenesis. T cell receptor (TCR) Tg mice are extremely useful in studying T cell-mediated immune responses because the majority of T cells in these mice express specific TCRs for partner antigens. In this review, we discuss the important studies utilizing TCR Tg mice to unveil underlying mechanisms of T cell-mediated immunopathogenesis during viral infections.

In-Situ Upgrading of Organosolv Lignin- and Cellulose-Derived Pyrolyzates Over Ce-MCM-41 Catalyst.

Lignocellulosic biomass, principally consisting of cellulose, hemicellulose and lignin, is a main renewable source for the production of biofuels and valuable chemicals. For instance, the polyaromatic structure of lignin fraction of biomass makes it a high potential feedstock for the production of valuable aromatic chemicals such as phenolic compounds. In this work, selective conversion of the organosolv lignin-derived pyrolyzates to alkylphenols was carried out using Ce-MCM-41 as In-Situ catalyst. Catalytic fast pyrolysis of the organosolv lignin was carried out on a tandem micro-pyrolyzer coupled with gas chromatography and mass spectrometry (GC-MS) detectors. The refined pyrolytic vapor was mainly consisting of phenolics (phenol, alkylphenols, guaiacol and alkylguaiacols), monoaromatic hydrocarbons (benzene, toluene and xylenes), esters (formic acid ethyl ester, acetic acid methyl ester and hexadecanoic acid methyl ester), aldehydes (formaldehyde and methylbenzaldehyde), acids (hydroxyacetic acid and benzoic acids), furans (2-methylfuran and dihydrofuran) and ethanol. Our data showed that the selectivity of products was influenced by pyrolysis temperature (500, 550 and 600 °C). Maximum selectivity of alkylphenols (10.3%) was obtained at 550 °C. Besides In-Situ pyrolysis of organosolve lignin, the In-Situ upgrading of the cellulose-derived pyrolyzates was carried out using Ce-MCM-41 at 550 °C. In-Situ pyrolysis of cellulose using Ce-MCM-41 could obtain high selectivity of aldehydes (11.4%), furans (9.6%) and ketones (3.2%).

In-Situ Catalytic Pyrolysis of Waste Lignin Over Desilicated Beta.

Desilicated Beta (DeBeta) was applied as the catalyst to the catalytic pyrolysis of waste lignin for the formation of aromatic hydrocarbon, and its performance was compared with that of the unmodified Beta. Large amounts of oxygen containing pyrolyzates were efficiently converted to stable aromatic hydrocarbons over both Beta and DeBeta catalysts. Compared to Beta, DeBeta exhibited the higher performance for the formation of aromatic hydrocarbons due to the enhanced diffusion efficiency through the mesopore.

Hydrodeoxygenation of Pyrolysis Bio-Oil Over Ni Impregnated Mesoporous Materials.

The catalytic hydrodeoxygenation (HDO) of bio-oil over Ni-supported mesoporous materials was performed using a high pressure autoclave reactor. The actual pyrolysis oil of cork oak wood was used as a sample, and Ni/Al-SBA-15 and Ni/Al-MSU-F were used as catalysts. In addition, supercritical ethanol was added as solvent. Both Ni-supported mesoporous catalysts showed efficient HDO reaction ability. A higher heating value and pH of bio-oil were achieved by the HDO reaction over both catalysts and upgraded bio-oil had a lower viscosity. Compared to Ni/Al-MSU-F, Ni/Al- SBA-15 produced more upgraded bio-oil with a lower oxygen content and higher heating value via a catalytic HDO process.

Application of mesoporous Al-MCM-48 material to the conversion of lignin.

Al-MCM-48 was applied to the catalytic pyrolysis of lignin for the first time. The pyrolysis reaction and in-situ product were analyzed by pyrolysis gas chromatography/mass spectrometry. The main products of the non-catalytic pyrolysis of lignin were phenols. The use of Al-MCM-48 increased the production of light phenols considerably. The yields of high-value-added compounds, such as hydrocarbons and aromatics, were also increased by catalytic upgrading. Al-MCM-48 is believed to promote cracking, aromatization and deoxygenation, such as decarbonylation. On the other hand, Si-MCM-48, which has no acid sites, showed lower deoxygenation efficiency than Al-MCM-48. Al-MCM-48 could be regenerated by calcining in air.

Apigenin's Therapeutic Potential Against Viral Infection.

Several antiviral drugs are clinically approved to treat influenza that is a highly prevalent acute respiratory disease. However, emerging drug-resistant virus strains undermine treatment efficacy, highlighting the exigency for novel antiviral drugs to counter these drug-resistant strains. Plants and their derivates have been historically utilized as medicinal remedies, and extensive studies have evidenced the antiviral potential of phytochemicals. Notably, apigenin is a predominant flavonoid with minimal toxicity and substantial therapeutic effects in various disease models. Despite its many anti-inflammatory, anti-oxidant, anti-cancer, anti-bacterial, and other beneficial bioactivities, existing reviews have yet to focus on apigenin's antiviral effects. Therefore, this review elucidates apigenin's therapeutic and antiviral properties in vitro and in vivo, discussing its mode of action and future prospects. Apigenin's remarkable inhibition by modulating multiple mechanisms against viruses has promising potential for novel plant-derived antiviral drugs and further clinical study developments.

Disruption of type I interferon pathway and reduced production of IFN-α by parabens in virus-infected dendritic cells.

BACKGROUND: Parabens are widely used preservatives commonly found in foods, cosmetics, and industrial products. Several studies have examined the effects of parabens on human health owing to widespread and continuous exposure to them in daily life. However, little is known about their immune-regulatory effects. OBJECTIVE: Here, we aimed to investigate whether methylparaben, ethylparaben, and propylparaben affect the function of dendritic cells (DCs) as the most potent antigen-presenting cells that play a critical role in the initiation of adaptive immune responses. METHODS: Bone-marrow derived DCs (BMDCs) were treated with three types of parabens (methylparaben, ethylparaben, and propylparaben) for 12 h. Subsequently, the transcriptomic profile was analyzed using RNA sequencing with further gene set enrichment analysis based on commonly regulated differentially expressed genes (DEGs). To test whether parabens suppress the production of type-I interferons (IFN-I) in BMDCs during viral infection, BMDCs or paraben-treated BMDCs were infected with Lymphocytic Choriomeningitis Virus (LCMV) at 10 multiplicity of infection (MOI) and measured the production of IFN-α1. RESULTS: Transcriptomic analyses revealed that all three types of parabens reduced the transcription levels of genes in virus infection-associated pathways, such as IFN-I responses in BMDCs. Furthermore, parabens considerably reduced IFN-α1 production in the virus-infected BMDCs. CONCLUSION: Our study is the first to show that parabens may modulate anti-viral immune responses by regulating DCs.

Galectin-4 increases the ability of M2 macrophages to enhance antiviral CD4+ T-cell responses.

Galectin-4 (Gal-4) is a ß-galactoside-binding protein belonging to the galectin family. Although Gal-4 is known to be involved in several physiologic processes of the gastrointestinal tract, its immunomodulatory roles remain unclear. In this study, we investigated whether Gal-4 influences the function of M1 and M2 macrophages. Gal-4 treatment drove more robust changes in the gene expression of M2 macrophages compared to M1 macrophages. Antiviral immune response-related genes were significantly upregulated in Gal-4-treated M2 macrophages. Gal-4 significantly enhanced the immunostimulatory activity of M2 macrophages upon Toll-like receptor 7 stimulation or infection with lymphocytic choriomeningitis virus (LCMV). Moreover, the antibody production against LCMV infection and the antiviral CD4+ T-cell responses, but not the antiviral CD8+ T-cell responses, were greatly increased by Gal-4-treated M2 macrophages in vivo. The present results indicate that Gal-4 enhances the ability of M2 macrophages to promote antiviral CD4+ T-cell responses. Thus, Gal-4 could be used to boost antiviral immune responses.

Anti-influenza A virus activity by Agrimonia pilosa and Galla rhois extract mixture.

Influenza A virus (IAV) continues to threaten human health. To date, two classes of antiviral drugs have been approved to treat IAV infection, but the continuous emergence of the drug-resistant IAV mutant reinforces the need to develop new antiviral drugs. In this study, we aimed to investigate the anti-IAV activity of an aqueous mixture of Agrimonia pilosa and Galla rhois extracts (APRG64). We demonstrated that APRG64 significantly reduced the IAV-induced cytopathic effect, the transcription/expression of viral proteins, and the production of infectious viral particles. Among nine major components of APRG64, apigenin was identified as the main ingredient responsible for the anti-IAV activity. Interestingly, APRG64 and apigenin inhibited the cell attachment and entry of virus and polymerase activity. Importantly, intranasal administration of APRG64 or apigenin strongly reduced viral loads in the lungs of IAV-infected mice. Furthermore, oral administration of APRG64 significantly reduced the level of viral RNAs and the expression level of pro-inflammatory cytokines in the lungs, which protected mice from IAV-induced mortality. In conclusion, APRG64 could be an attractive antiviral drug to treat IAV infection.

Inhibition of KIF20A suppresses the replication of influenza A virus by inhibiting viral entry.

The influenza A virus (IAV) has caused several pandemics, and therefore there are many ongoing efforts to identify novel antiviral therapeutic strategies including vaccines and antiviral drugs. However, influenza viruses continuously undergo antigenic drift and shift, resulting in the emergence of mutated viruses. In turn, this decreases the efficiency of existing vaccines and antiviral drugs to control IAV infection. Therefore, this study sought to identify alternative therapeutic strategies targeting host cell factors rather than viruses to avoid infection by mutated viruses. Particularly, we investigated the role of KIF20A that is one of kinesin superfamily proteins in the replication of IAV. The KIF20A increased viral protein levels in IAV-infected cells by regulating the initial entry stage during viral infection. Furthermore, the KIF20A inhibitor significantly suppressed viral replication, which protected mice from morbidity and mortality. Therefore, our findings demonstrated that KIF20A is highly involved in the viral replication process and viral propagation both in vitro and in vivo, and could thus be used as a target for the development of novel antiviral drugs.

Catalytic Conversion of Pinus densiflora Over Mesoporous Catalysts Using Pyrolysis Process.

Catalytic pyrolysis experiments were conducted to investigate the possibility of obtaining valuable chemicals from Pinus densiflora, a native Korean tree species occupying 21.4% of the total area under forests in South Korea. Two representative mesoporous catalysts, Al-MCM-41 and Al-MSU-F, as well as hierarchical mesoporous MFI (Meso-MFI) that has both mesopores and micropores, were used as catalysts. Compared to non-catalytic pyrolysis, catalytic pyrolysis was shown to reduce the fractions of levoglucosan, phenolics, and acids in bio-oil, while increasing the fractions of aromatics, PAHs, and furans. Meso-MFI with strong acid sites showed a high selectivity toward aromatics and PAHs, whereas Al-MCM-41 and Al-MSU-F with weak acid sites exhibited a high selectivity toward furanic compounds. The results of this study indicate that choosing a catalyst with an adequate quantity of acidic sites with the required strength is critical for enhancing the production of desired chemicals from Pinus densiflora.