Social issues and emerging debates in tourism and hospitality

The authors specifically frame tourists' decision making using Schmoll's tourism consumer choice model and propose spiritual tourism experiences as alternatives to drug use along the Hummus Trail. A review of research into social tourism: Launching the annals of tourism research curated collection on social tourism. The maturing field of tourism research has also birthed affiliated research streams such as tourism geographies, tourism economics, and tourism and medical interventions (e.g. Wen et al., [17]). The tourism and hospitality industry has earned global recognition thanks to its unprecedented growth prior to the COVID-19 pandemic. [Extracted from the article] Copyright of Anatolia: An International Journal of Tourism & Hospitality Research is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

FBXO11 amplifies type I interferon signaling to exert antiviral effects by facilitating the assemble of TRAF3-TBK1-IRF3 complex.

As the key component of host innate antiviral immunity, type I interferons (IFN-Is) exert multiple antiviral effects by inducing hundreds of IFN-stimulated genes. However, the precise mechanism involved in host sensing of IFN-I signaling priming is particularly complex and remains incompletely resolved. This research identified F-box protein 11 (FBXO11), a component of the E3-ubiquitin ligase SKP/Cullin/F-box complex, acted as an important regulator of IFN-I signaling priming and antiviral process against several RNA/DNA viruses. FBXO11 functioned as an essential enhancer of IFN-I signaling by promoting the phosphorylation of TBK1 and IRF3. Mechanistically, FBXO11 facilitated the assembly of TRAF3-TBK1-IRF3 complex by mediating the K63 ubiquitination of TRAF3 in a NEDD8-dependent manner to amplify the activation of IFN-I signaling. Consistently, the NEDD8-activating enzyme inhibitor MLN4921 could act as a blocker for FBXO11-TRAF3-IFN-I axis of signaling. More significantly, examination of clinical samples of chronic hepatitis B virus (HBV) infection and public transcriptome database of severe acute respiratory syndrome coronavirus-2-, HBV-, and hepatitis C virus-infected human samples revealed that FBXO11 expression was positively correlated with the stage of disease course. Taken together, these findings suggest that FBXO11 is an amplifier of antiviral immune responses and might serve as a potential therapeutic target for a number of different viral diseases.

Multiple SARS-CoV-2 Variants Exhibit Variable Target Cell Infectivity and Ability to Evade Antibody Neutralization.

The continuous emergence of SARS-coronavirus 2 (SARS-CoV-2) variants, especially the variants of concern (VOC), exacerbated the impact of the coronavirus disease 2019 (COVID-19) pandemic. As the key of viral entry into host cells, the spike (S) protein is the major target of therapeutic monoclonal antibodies (mAbs) and polyclonal antibodies elicited by infection or vaccination. However, the mutations of S protein in variants may change the infectivity and antigenicity of SARS-CoV-2, leading to the immune escape from those neutralizing antibodies. To characterize the mutations of S protein in newly emerging variants, the proteolytic property and binding affinity with receptor were assessed, and the vesicular stomatitis virus (VSV)-based pseudovirus system was used to assess the infectivity and immune escape. We found that some SARS-CoV-2 variants have changed significantly in viral infectivity; especially, B.1.617.2 is more likely to infect less susceptible cells than D614G, and the virus infection process can be completed in a shorter time. In addition, neutralizing mAbs and vaccinated sera partially or completely failed to inhibit host cell entry mediated by the S protein of certain SARS-CoV-2 variants. However, SARS-CoV-2 variant S protein-mediated viral infection can still be blocked by protease inhibitors and endocytosis inhibitors. This work provides a deeper understanding of the rise and evolution of SARS-CoV-2 variants and their immune evasion.

Corrigendum: Characterization of SARS-CoV-2 Variants N501Y.V1 and N501Y.V2 Spike on Viral Infectivity.

[This corrects the article DOI: 10.3389/fcimb.2021.720357.].

Characterization of SARS-CoV-2 Variants N501Y.V1 and N501Y.V2 Spike on Viral Infectivity.

SARS-coronavirus 2 (SARS-CoV-2), pathogen of coronavirus disease 2019 (COVID-19), is constantly evolving to adapt to the host and evade antiviral immunity. The newly emerging variants N501Y.V1 (B.1.1.7) and N501Y.V2 (B.1.351), first reported in the United Kingdom and South Africa respectively, raised concerns due to the unusually rapid global spread. The mutations in spike (S) protein may contribute to the rapid spread of these variants. Here, with a vesicular stomatitis virus (VSV)-based pseudotype system, we demonstrated that the pseudovirus bearing N501Y.V2 S protein has higher infection efficiency than pseudovirus with wildtype (WT) and D614G S protein. Moreover, pseudovirus with N501Y.V1 or N501Y.V2 S protein has better thermal stability than WT and D614G, suggesting these mutations of variants may increase the stability of SARS-CoV-2 S protein and virion. However, the pseudovirus bearing N501Y.V1 or N501Y.V2 S protein has similar sensitivity to inhibitors of protease and endocytosis with WT and D614G. These findings could be of value in preventing the spread of virus and developing drugs for emerging SARS-CoV-2 variants.

Direct inhibitory effect on viral entry of influenza A and SARS-CoV-2 viruses by azithromycin.

OBJECTIVES: Using strategy of drug repurposing, antiviral agents against influenza A virus (IAV) and newly emerging SARS-coronavirus 2 (SARS-CoV-2, also as 2019-nCoV) could be quickly screened out. MATERIALS AND METHODS: A previously reported engineered replication-competent PR8 strain carrying luciferase reporter gene (IAV-luc) and multiple pseudotyped IAV and SARS-CoV-2 virus was used. To specifically evaluate the pH change of vesicles containing IAV, we constructed an A549 cell line with endosomal and lysosomal expression of pHluorin2. RESULTS: Here, we identified azithromycin (AZ) as an effective inhibitor against multiple IAV and SARS-CoV-2 strains. We found that AZ treatment could potently inhibit IAV infection in vitro. Moreover, using pseudotyped virus model, AZ could also markedly block the entry of SARS-CoV-2 in HEK293T-ACE2 and Caco2 cells. Mechanistic studies further revealed that such effect was independent of interferon signalling. AZ treatment neither impaired the binding and internalization of IAV virions, nor the viral replication, but rather inhibited the fusion between viral and vacuolar membranes. Using a NPC1-pHluorin2 reporter cell line, we confirmed that AZ treatment could alkalize the vesicles containing IAV virions, thereby preventing pH-dependent membrane fusion. CONCLUSIONS: Overall, our findings demonstrate that AZ can exert broad-spectrum antiviral effects against IAV and SARS-CoV-2, and could be served as a potential clinical anti-SARS-CoV-2 drug in emergency as well as a promising lead compound for the development of next-generation anti-IAV drugs.