Zika virus (ZIKV) infection is a public health emergency and host innate immunity is essential for the control of virus infection. The NLRP3 inflammasome plays a key role in host innate immune ...responses by activating caspase-1 to facilitate interleukin-1β (IL-1β) secretion. Here we report that ZIKV stimulates IL-1β secretion in infected patients, human PBMCs and macrophages, mice, and mice BMDCs. The knockdown of NLRP3 in cells and knockout of NLRP3 in mice inhibit ZIKV-mediated IL-1β secretion, indicating an essential role for NLRP3 in ZIKV-induced IL-1β activation. Moreover, ZIKV NS5 protein is required for NLRP3 activation and IL-1β secretion by binding with NLRP3 to facilitate the inflammasome complex assembly. Finally, ZIKV infection in mice activates IL-1β secretion, leading to inflammatory responses in the mice brain, spleen, liver, and kidney. Thus we reveal a mechanism by which ZIKV induces inflammatory responses by facilitating NLRP3 inflammasome complex assembly and IL-1β activation.
One of the fundamental reactions of the innate immune responses to pathogen infection is the release of pro-inflammatory cytokines, including IL-1β, processed by the NLRP3 inflammasome. The ...stimulator of interferon genes (STING) has the essential roles in innate immune response against pathogen infections. Here we reveal a distinct mechanism by which STING regulates the NLRP3 inflammasome activation, IL-1β secretion, and inflammatory responses in human cell lines, mice primary cells, and mice. Interestingly, upon HSV-1 infection and cytosolic DNA stimulation, STING binds to NLRP3 and promotes the inflammasome activation through two approaches. First, STING recruits NLRP3 and facilitates NLRP3 localization in the endoplasmic reticulum, thereby facilitating the inflammasome formation. Second, STING interacts with NLRP3 and attenuates K48- and K63-linked polyubiquitination of NLRP3, thereby promoting the inflammasome activation. Collectively, we demonstrate that the cGAS-STING-NLRP3 signaling is essential for host defense against HSV-1 infection.
In this study, we searched Pubmed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), and WanFang from inception to 21 November 2018 for studies reporting TM infection in people ...living with HIV/AIDS (PLWHA). Our meta-analysis included studies investigating the prevalence of TM infection in PLWHA. Reviews, duplicate studies, and animal studies were excluded. A random effects model was used to estimate pooled prevalence, and meta-regression analysis was conducted to explore potential factors for heterogeneity. 159,064 patients with HIV infection in 33 eligible studies were included in our meta-analysis. The pooled prevalence of TM infection in PLWHA was 3.6%. Vietnam had the highest prevalence (6.4%), followed by Thailand (3.9%), China (3.3%), India (3.2%) and Malaysia (2.1%). In China, TM infection was most prevalent in South China (15.0%), while the burden in Southwest China was not very heavy (0.3%). CD4+ T-cell counts below 200 cells/mm.sup.3 contributed to the increased risk of TM infection in PLWHA (OR 12.68, 95%CI: 9.58-16.77). However, access to ART did not significantly decrease the risk of TM infection in PLWHA. The burden of TM infection in Asia is heavy, and varies from region to region. PLWHA in lower latitude areas are more likely to suffer from TM infection. Optimization of diagnostic tools and universal screening for TM in vulnerable people to ensure early case detection and prompt antifungal treatment should be considered.
Abstract
Background
College students were the key group we should pay more attention for acquired immune deficiency syndrome (AIDS) prevention and control in recent years in China. Few studies of HIV ...non-occupational post-exposure prophylaxis (nPEP) knowledge and service acceptance had been conducted among them in China. This study conducted a cross-sectional survey to understand the service acceptance of nPEP and its influencing factors among college students in the three cities of China.
Methods
A questionnaire survey was conducted to collect information on socio-demographic, behavioral characteristic, HIV/AIDS knowledge, nPEP knowledge, acceptance of nPEP services among the college students in Beijing, Shenzhen, and Kunming of China from March to April of 2019. Each participant completed an anonymous questionnaire on line by computer-assisted or mobile phone-assisted self-interview with informed consent. Multivariable logistic regression analyses identified predictors for service acceptance of nPEP.
Results
A total of 4698 students were surveyed with the average age of 20 years old. 98.0% (4605/4698) of them were undergraduates, 21.8%(1022/4698) had sexual intercourse; 48.6% (2282/4698) heard of nPEP, among which 4.95%(113/2282) received nPEP services. The awareness rate of HIV/AIDS knowledge was 85.6% (5495/4698) with the differences statistically significant between the three cities. The awareness rate of nPEP knowledge was 16.5% (774/4698). There were significant differences in receiving nPEP services among students of different ages, genders, sexual behaviors, and knowledge of HIV/AIDS by univariate analysis. Multivariable analyses indicated that age group of 18 and under (
OR
= 2.551, 95%
CI
= 1.153–5.646), male (
OR
= 3.131, 95%
CI
= 1.866–5.253), homosexual behavior (
OR
= 4.661,95%
CI
= 2.658–8.172), heterosexual behavior (
OR
= 1.676, 95%
CI
= 1.040–2.947), no awareness of AIDS knowledge (
OR
= 3.882, 95%
CI
= 2.371–6.356) and nPEP (
OR
= 4.788, 95%
CI
= 2.50–9.169) knowledge, were associated with the service acceptance of nPEP among the college students.
Conclusion
The low acceptance of nPEP services was mainly affected by low level of nPEP knowledge among the college students. Further publicity and education of nPEP knowledge were necessary, as well as promotion of knowledge of HIV/AIDS prevention and treatment. More attention should be paid to the factors associated with acceptance of nPEP services.
Hepatitis B virus (HBV) chronically infects 296 million individuals and there is no cure. As an important step of viral life cycle, the mechanisms of HBV egress remain poorly elucidated. With ...proteomic approach to identify capsid protein (HBc) associated host factors and siRNA screen, we uncovered tumor susceptibility gene 101 (TSG101). Knockdown of TSG101 in HBV-producing cells, HBV-infected cells and HBV transgenic mice suppressed HBV release. Co-immunoprecipitation and site mutagenesis revealed that VFND motif in TSG101 and Lys-96 ubiquitination in HBc were essential for TSG101-HBc interaction. In vitro ubiquitination experiment demonstrated that UbcH6 and NEDD4 were potential E2 ubiquitin-conjugating enzyme and E3 ligase that catalyzed HBc ubiquitination, respectively. PPAY motif in HBc and Cys-867 in NEDD4 were required for HBc ubiquitination, TSG101-HBc interaction and HBV egress. Transmission electron microscopy confirmed that TSG101 or NEDD4 knockdown reduces HBV particles count in multivesicular bodies (MVBs). Our work indicates that TSG101 recognition for NEDD4 ubiquitylated HBc is critical for MVBs mediated HBV egress.
Extracellular adenosine triphosphate (ATP), a key danger-associated molecular pattern (DAMP) molecule, is released to the extracellular medium during inflammation by injured parenchymal cells, dying ...leukocytes, and activated platelets. ATP directly activates the plasma membrane channel P2X7 receptor (P2X7R), leading to an intracellular influx of K
, a key trigger inducing NLRP3 inflammasome activation. However, the mechanism underlying P2X7R-mediated activation of NLRP3 inflammasome is poorly understood, and additional molecular mediators have not been identified. Here, we demonstrate that Paxillin is the molecule connecting the P2X7 receptor and NLRP3 inflammasome through protein interactions.
We show a distinct mechanism by which Paxillin promotes ATP-induced activation of the P2X7 receptor and NLRP3 inflammasome. Extracellular ATP induces Paxillin phosphorylation and then facilitates Paxillin-NLRP3 interaction. Interestingly, Paxillin enhances NLRP3 deubiquitination and activates NLRP3 inflammasome upon ATP treatment and K
efflux. Moreover, we demonstrated that USP13 is a key enzyme for Paxillin-mediated NLRP3 deubiquitination upon ATP treatment. Notably, extracellular ATP promotes Paxillin and NLRP3 migration from the cytosol to the plasma membrane and facilitates P2X7R-Paxillin interaction and PaxillinNLRP3 association, resulting in the formation of the P2X7R-Paxillin-NLRP3 complex. Functionally, Paxillin is essential for ATP-induced NLRP3 inflammasome activation in mouse BMDMs and BMDCs as well as in human PBMCs and THP-1-differentiated macrophages.
We have identified paxillin as a mediator of NLRP3 inflammasome activation. Paxillin plays key roles in ATP-induced activation of the P2X7 receptor and NLRP3 inflammasome by facilitating the formation of the P2X7R-Paxillin-NLRP3 complex.
Modulating the precise self-assembly of functional biomacromolecules is a critical challenge in biotechnology. Herein, functional biomacromolecule-assembled hierarchical hybrid nanoarchitectures in a ...spatially controlled fashion are synthesized, achieving the biorecognition behavior and signal amplification in the immunoassay simultaneously. Biomacromolecules with sequential assembly on the scaffold through the biomineralization process show significantly enhanced stability, bioactivity, and utilization efficiency, allowing tuning of their functions by modifying their size and composition. The hierarchically hybrid nanoarchitectures show great potential in construction of ultrasensitive immunoassay platforms, achieving a three order-of-magnitude increase in sensitivity. Notably, the well-designed HRP@Ab2 nanoarchitectures allow for optical immunoassays with a detection range from picogram mL–1 to microgram mL–1 on demand, providing great promise for quantitative analysis of both low-abundance and high-residue targets for biomedical applications.
During host-virus co-evolution, cells develop innate immune systems to inhibit virus invasion, while viruses employ strategies to suppress immune responses and maintain infection. Here, we reveal ...that Zika virus (ZIKV), a re-emerging arbovirus causing public concerns and devastating complications, restricts host immune responses through a distinct mechanism. ZIKV nonstructural protein 5 (NS5) interacts with the host retinoic acid-inducible gene I (RIG-I), an essential signaling molecule for defending pathogen infections. NS5 subsequently represses K63-linked polyubiquitination of RIG-I, attenuates the phosphorylation and nuclear translocation of interferon regulatory factor 3 (IRF3), and inhibits the expression and production of interferon-β (IFN-β), thereby restricting the RIG-I signaling pathway. Interestingly, we demonstrate that the methyltransferase (MTase) domain of NS5 is required for the repression of RIG-I ubiquitination, IRF3 activation, and IFN-β production. Detailed studies further reveal that the conservative active site D146 of NS5 is critical for the suppression of the RIG-I signaling. Therefore, we uncover an essential role of NS5 conservative site D146 in ZIKV-mediated repression of innate immune system, illustrate a distinct mechanism by which ZIKV evades host immune responses, and discover a potential target for anti-viral infection.
The digital economy is considered as an effective measure to mitigate the negative economic impact of the Corona Virus Disease 2019 (COVID-19) epidemic. However, few studies evaluated the role of ...digital economy on the economic growth of countries along the "Belt and Road" and the impact of COVID-19 on their digital industries. This study constructed a comprehensive evaluation index system and applied a panel data regression model to empirically analyze the impact of digital economy on the economic growth of countries along the "Belt and Road" before COVID-19. Then, a Global Trade Analysis Project (GTAP) model was used to examine the impact of COVID-19 on their digital industries and trade pattern. Our results show that although there is an obvious regional imbalance in the digital economy development in countries along the "Belt and Road", the digital economy has a significantly positive effect on their economic growth. The main impact mechanism is through promoting industrial structure upgrading, the total employment and restructuring of employment. Furthermore, COVID-19 has generally boosted the demand for the digital industries, and the impact from the demand side is much larger than that from the supply side. Specifically, the digital industries in Armenia, Israel, Latvia and Estonia have shown great growth potential during the epidemic. On the contrast, COVID-19 has brought adverse impacts to the digital industries in Ukraine, Egypt, Turkey, and the Philippines. The development strategies are proposed to bridge the "digital divide" of countries along the "Belt and Road," and to strengthen the driving effect of the digital economy on industrial upgrading, employment and trade in the post-COVID-19 era.
The widespread use of antiretroviral therapy (ART) has raised concerns about the emergence of HIV transmitted drug resistance (TDR). Acute HIV infection (AHI) was the most appropriate time to detect ...the spread of TDR. In this meta-analysis, our purpose was to evaluate the level of TDR in ART-naive patients with primary HIV infection (PHI)/AHI/early HIV infection (EHI) and to describe the critical drug-resistant mutations.
We systematically searched the literature between January 1, 2008, and April 30, 2021, in PubMed, Web of Science, Embase, and the Cochrane Library. To evaluate the overall prevalence of TDR, we extracted raw data and analyzed prevalence estimates using Stata SE.
The data of this meta-analysis come from 12 observational studies, covering 3,558 ART-naive individuals with PHI, AHI, or EHI. The overall prevalence of HIV-TDR is 9.3% (95% CI: 6.8%-11.8%, I
= 81.1%, in 11 studies). The prevalence of resistance by drug class is the highest for the nonnucleoside reverse transcriptase inhibitors (NNRTIs) at 5.7% (95% CI: 2.9%-8.5%, I
= 96.6%, in 11 studies), followed by nucleoside reverse transcriptase inhibitors (NRTIs) at 3.4% (95% CI: 1.8%-5.0%, I
= 86.3%, in 10 studies) and protease inhibitors (PIs) at 3.3% (95% CI: 2.7%-3.9%, I
= 15.6%, in 10 studies). The prevalence of TDR to integrase inhibitors (INIs) is 0.3% (95% CI: 0.1%-0.7%, I
= 95.9%, in three studies), which is the lowest among all antiretroviral drugs.
The overall prevalence of TDR is at a moderate level among AHI patients who have never received ART. This emphasizes the importance of baseline drug resistance testing for public health surveillance and guiding the choice of ART. In addition, the prevalence of TDR to NNRTIs is the highest, while the TDR to INIs is the lowest. This may guide the selection of clinical antiretroviral drugs.
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