ABSTRACT
BACKGROUND: Nasal and paranasal sinus abnormalities may be related to nasolacrimal duct obstructive disease but are strongly debated. Data of acute disease stage are lacking. OBJECTIVE: The purpose of this study was to determine if there are correlations between radiologic signs of sinus inflammation and acute dacryocystitis (AD). METHODS: This cross-sectional controlled study was conducted at Wenzhou, Zhejiang Province, China from February 2021 to November 2023. Forty-four consecutive patients with AD and 50 consecutive patients with orbital tumors (the control group), who completed preoperative computed tomography scans, were enrolled to evaluate the extent of their inflammatory sinonasal disease by the modified Lund-Mackay score system. RESULTS: The inflammation signs of the paranasal sinuses (total mean sinus scores, 95% CI [0.00, 2.00]; P < 0.001), namely the anterior ethmoid sinus(95% CI [0.00, 1.00]; P < 0.001), the posterior ethmoid sinus(95% CI [0.00, 0.00]; P = 0.003), the frontal sinus (95% CI [0.00, 0.00]; P = 0.02), and the ostiomeatal complex (P < 0.001) were more extensive in patients with AD when compared with the controls. The disease course was negatively correlated with the anterior ethmoid (P = 0.03) and frontal scores (P = 0.01). The symptom of eyelid swelling was positively correlated with the anterior ethmoid (P = 0.03), ostiomeatal complex (P = 0.004), and total sinus scores (P = 0.005). CONCLUSION: Inflammatory sinus disease was found to be more frequent in patients with AD, which was gradually alleviated with the prolongation of the disease course. The mutual spread of inflammation particularly in the acute course may play an important role in lacrimal duct obstructive disease.
ABSTRACT
The commensal microbiota of the mosquito gut plays a complex role in determining the vector competence for arboviruses. In this study, we identified a bacterium from the gut of field Aedes albopictus mosquitoes named Rosenbergiella sp. YN46 (Rosenbergiella_YN46) that rendered mosquitoes refractory to infection with dengue and Zika viruses. Inoculation of 1.6 × 103 colony forming units (CFUs) of Rosenbergiella_YN46 into A. albopictus mosquitoes effectively prevents viral infection. Mechanistically, this bacterium secretes glucose dehydrogenase (RyGDH), which acidifies the gut lumen of fed mosquitoes, causing irreversible conformational changes in the flavivirus envelope protein that prevent viral entry into cells. In semifield conditions, Rosenbergiella_YN46 exhibits effective transstadial transmission in field mosquitoes, which blocks transmission of dengue virus by newly emerged adult mosquitoes. The prevalence of Rosenbergiella_YN46 is greater in mosquitoes from low-dengue areas (52.9 to ~91.7%) than in those from dengue-endemic regions (0 to ~6.7%). Rosenbergiella_YN46 may offer an effective and safe lead for flavivirus biocontrol.
Subject(s)
Aedes , Dengue Virus , Mosquito Vectors , Symbiosis , Zika Virus , Animals , Aedes/microbiology , Aedes/virology , Dengue Virus/physiology , Mosquito Vectors/virology , Mosquito Vectors/microbiology , Zika Virus/physiology , Dengue/transmission , Dengue/virology , Dengue/prevention & control , Gastrointestinal Microbiome , Acetobacteraceae/physiology , Female , Viral Envelope Proteins/metabolism , Viral Envelope Proteins/genetics , Flavivirus/physiology , Flavivirus/genetics , Zika Virus Infection/transmission , Zika Virus Infection/virologyABSTRACT
Mosquito-borne flaviviruses such as dengue (DENV) and Zika (ZIKV) cause hundreds of millions of infections annually. The single-stranded RNA genome of flaviviruses is translated into a polyprotein, which is cleaved equally into individual functional proteins. While structural proteins are packaged into progeny virions and released, most of the nonstructural proteins remain intracellular and could become cytotoxic if accumulated over time. However, the mechanism by which nonstructural proteins are maintained at the levels optimal for cellular fitness and viral replication remains unknown. Here, we identified that the ubiquitin E3 ligase HRD1 is essential for flaviviruses infections in both mammalian hosts and mosquitoes. HRD1 directly interacts with flavivirus NS4A and ubiquitylates a conserved lysine residue for ER-associated degradation. This mechanism avoids excessive accumulation of NS4A, which otherwise interrupts the expression of processed flavivirus proteins in the ER. Furthermore, a small-molecule inhibitor of HRD1 named LS-102 effectively interrupts DENV2 infection in both mice and Aedes aegypti mosquitoes, and significantly disturbs DENV transmission from the infected hosts to mosquitoes owing to reduced viremia. Taken together, this study demonstrates that flaviviruses have evolved a sophisticated mechanism to exploit the ubiquitination system to balance the homeostasis of viral proteins for their own advantage and provides a potential therapeutic target to interrupt flavivirus infection and transmission.
Subject(s)
Aedes , Flavivirus Infections , Flavivirus , Zika Virus Infection , Zika Virus , Animals , Mice , Flavivirus/genetics , Zika Virus/genetics , Ubiquitin/metabolism , Ligases/metabolism , Viral Proteins/metabolism , MammalsABSTRACT
A full understanding of the inactivated COVID-19 vaccine-mediated antibody responses to SARS-CoV-2 circulating variants will inform vaccine effectiveness and vaccination development strategies. Here, we offer insights into the inactivated vaccine-induced antibody responses after prime-boost vaccination at both the polyclonal and monoclonal levels. We characterized the VDJ sequence of 118 monoclonal antibodies (mAbs) and found that 20 neutralizing mAbs showed varied potency and breadth against a range of variants including XBB.1.5, BQ.1.1, and BN.1. Bispecific antibodies (bsAbs) based on nonoverlapping mAbs exhibited enhanced neutralizing potency and breadth against the most antibody-evasive strains, such as XBB.1.5, BQ.1.1, and BN.1. The passive transfer of mAbs or their bsAb effectively protected female hACE2 transgenic mice from challenge with an infectious Delta or Omicron BA.2 variant. The neutralization mechanisms of these antibodies were determined by structural characterization. Overall, a broad spectrum of potent and distinct neutralizing antibodies can be induced in individuals immunized with the SARS-CoV-2 inactivated vaccine BBIBP-CorV, suggesting the application potential of inactivated vaccines and these antibodies for preventing infection by SARS-CoV-2 circulating variants.
Subject(s)
COVID-19 Vaccines , COVID-19 , Female , Animals , Mice , Humans , SARS-CoV-2/genetics , COVID-19/prevention & control , Antibodies, Monoclonal , Antibodies, Neutralizing , Mice, Transgenic , Vaccines, Inactivated , Antibodies, ViralABSTRACT
Ebola virus (EBOV) is an enveloped negative-sense RNA virus and a member of the filovirus family. Nucleoprotein (NP) expression alone leads to the formation of inclusion bodies (IBs), which are critical for viral RNA synthesis. The matrix protein, VP40, not only plays a critical role in virus assembly/budding, but also can regulate transcription and replication of the viral genome. However, the molecular mechanism by which VP40 regulates viral RNA synthesis and virion assembly/budding is unknown. Here, we show that within IBs the N-terminus of NP recruits VP40 and is required for VLP-containing NP release. Furthermore, we find four point mutations (L692A, P697A, P698A and W699A) within the C-terminal hydrophobic core of NP result in a stronger VP40-NP interaction within IBs, sequestering VP40 within IBs, reducing VP40-VLP egress, abolishing the incorporation of NC-like structures into VP40-VLP, and inhibiting viral RNA synthesis, suggesting that the interaction of N-terminus of NP with VP40 induces a conformational change in the C-terminus of NP. Consequently, the C-terminal hydrophobic core of NP is exposed and binds VP40, thereby inhibiting RNA synthesis and initiating virion assembly/budding.
Subject(s)
Ebolavirus/physiology , Nucleocapsid Proteins/metabolism , RNA, Viral/metabolism , Viral Matrix Proteins/metabolism , Virion/metabolism , Virus Assembly , HEK293 Cells , HeLa Cells , Humans , Nucleocapsid Proteins/genetics , RNA, Viral/genetics , Viral Matrix Proteins/genetics , Virion/geneticsABSTRACT
The final stage of Ebola virus (EBOV) replication is budding from host cells, where the matrix protein VP40 is essential for driving this process. Many post-translational modifications such as ubiquitination are involved in VP40 egress, but acetylation has not been studied yet. Here, we characterize NEDD4 is acetylated at a conserved Lys667 mediated by the acetyltransferase P300 which drives VP40 egress process. Importantly, P300-mediated NEDD4 acetylation promotes NEDD4-VP40 interaction which enhances NEDD4 E3 ligase activity and is essential for the activation of VP40 ubiquitination and subsequent egress. Finally, we find that Zaire ebolavirus production is dramatically reduced in P300 knockout cell lines, suggesting that P300-mediated NEDD4 acetylation may have a physiological effect on Ebola virus life cycle. Thus, our study identifies an acetylation-dependent regulatory mechanism that governs VP40 ubiquitination and provides insights into how acetylation controls EBOV VP40 egress.
Subject(s)
Hemorrhagic Fever, Ebola/metabolism , Nedd4 Ubiquitin Protein Ligases/metabolism , Viral Matrix Proteins/metabolism , Virus Release/physiology , p300-CBP Transcription Factors/metabolism , Acetylation , Cell Line , Ebolavirus/physiology , HumansABSTRACT
Enterovirus 71 (EV71) belonging to the Picornaviridae family is considered the most frequently detected causative agent in hand-foot-and-mouth disease (HFMD) and is a serious threat to public health in the Asia-Pacific region. There are currently no approved vaccines or effective drugs for EV71. In this study, using recombinant vesicular stomatitis virus (rVSV) expressing viral VP1 protein (mVP1) of EV71 as a control, we generated two types of rVSVs that can form EV71 virus-like particles (VLPs). First, we co-infected two rVSVs singly expressing P1 (mP1) and 3CD (m3CD) of EV71. Second, we inserted P1 and 3CD into one VSV backbone to generate an rVSV expressing P1 and 3CD together (mP1-3CD). When P1 and 3CD were expressed in the cells either co-infected with mP1 and m3CD (mP1/m3CD) or infected with mP1-3CD, P1 was cleaved by 3CD and produced VP1, VP3, and VP0 to form VLPs. Furthermore, mice immunized with mP1/m3CD or mP1-3CD showed higher humoral and cellular immunity responses than mice immunized with mVP1. Finally, the rVSVs expressing the EV71 proteins were evaluated in mice to determine their potential to protect against a lethal EV71 virus challenge, and among all the rVSVs, the mP1-3CD was shown to be the most promising vaccine candidate for EV71 protection.