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Journal of Virology Jun 2024Ebola virus glycoprotein (EBOV GP) is one of the most heavily O-glycosylated viral glycoproteins, yet we still lack a fundamental understanding of the structure of its...
Targeting host O-linked glycan biosynthesis affects Ebola virus replication efficiency and reveals differential GalNAc-T acceptor site preferences on the Ebola virus glycoprotein.
Ebola virus glycoprotein (EBOV GP) is one of the most heavily O-glycosylated viral glycoproteins, yet we still lack a fundamental understanding of the structure of its large O-glycosylated mucin-like domain and to what degree the host O-glycosylation capacity influences EBOV replication. Using tandem mass spectrometry, we identified 47 O-glycosites on EBOV GP and found similar glycosylation signatures on virus-like particle- and cell lysate-derived GP. Furthermore, we performed quantitative differential O-glycoproteomics on proteins produced in wild-type HEK293 cells and cell lines ablated for the three key initiators of O-linked glycosylation, GalNAc-T1, -T2, and -T3. The data show that 12 out of the 47 O-glycosylated sites were regulated, predominantly by GalNAc-T1. Using the glycoengineered cell lines for authentic EBOV propagation, we demonstrate the importance of O-linked glycan initiation and elongation for the production of viral particles and the titers of progeny virus. The mapped O-glycan positions and structures allowed to generate molecular dynamics simulations probing the largely unknown spatial arrangements of the mucin-like domain. The data highlight targeting or as a possible way to modulate O-glycan density on EBOV GP for novel vaccine designs and tailored intervention approaches.IMPORTANCEEbola virus glycoprotein acquires its extensive glycan shield in the host cell, where it is decorated with N-linked glycans and mucin-type O-linked glycans. The latter is initiated by a family of polypeptide GalNAc-transferases that have different preferences for optimal peptide substrates resulting in a spectrum of both very selective and redundant substrates for each isoform. In this work, we map the exact locations of O-glycans on Ebola virus glycoprotein and identify subsets of sites preferentially initiated by one of the three key isoforms of GalNAc-Ts, demonstrating that each enzyme contributes to the glycan shield integrity. We further show that altering host O-glycosylation capacity has detrimental effects on Ebola virus replication, with both isoform-specific initiation and elongation playing a role. The combined structural and functional data highlight glycoengineered cell lines as useful tools for investigating molecular mechanisms imposed by specific glycans and for steering the immune responses in future vaccine designs.
Topics: Ebolavirus; Humans; Virus Replication; HEK293 Cells; Glycosylation; Polysaccharides; Viral Envelope Proteins; Hemorrhagic Fever, Ebola; N-Acetylgalactosaminyltransferases; Glycoproteins; Polypeptide N-acetylgalactosaminyltransferase
PubMed: 38757972
DOI: 10.1128/jvi.00524-24 -
Veterinaria Italiana Mar 2024This study was conducted to estimate the seroprevalence of Peste des petits ruminants virus (PPRV) and to determine the virus distribution in unvaccinated goats in the...
This study was conducted to estimate the seroprevalence of Peste des petits ruminants virus (PPRV) and to determine the virus distribution in unvaccinated goats in the Pantnagar region of Uttarakhand state, India. A total of 212 serum samples from goats were collected randomly from various villages in three districts (Udhamsingh Nagar, Nainital, and Almora) of Uttarakhand. Serum samples were tested for anti-PPRV antibodies by a commercially available kit. RNA was extracted from the clinical samples and it was subjected to one-step RT-PCR, followed by virus isolation from positive samples. A total of 41 animals from various villages were found to be seropositive with a prevalence rate of 19.33%. PPR outbreaks were also reported from the Tarai region of Uttarakhand, and detection by PCR confirmed PPRV in 8 goats. Two representative swab samples were subjected to virus isolation in Vero cells and both samples showed typical cytopathic effects. The present study shows that PPRV is circulating in the Tarai region of Uttarakhand and mass vaccination for PPR must be followed in this region to increase herd immunity to a protective level. To the best of our knowledge, this is the first investigation of PPRV seroprevalence in unvaccinated goats of Uttarakhand, India.
Topics: Animals; Peste-des-Petits-Ruminants; India; Peste-des-petits-ruminants virus; Goats; Goat Diseases; Seroepidemiologic Studies
PubMed: 38757513
DOI: 10.12834/VetIt.2988.21721.3 -
Euro Surveillance : Bulletin Europeen... May 2024
Letter to the editor: Atypical age distribution and high disease severity in children with RSV infections during two irregular epidemic seasons throughout the COVID-19 pandemic.
Topics: Humans; COVID-19; Respiratory Syncytial Virus Infections; SARS-CoV-2; Child, Preschool; Infant; Child; Severity of Illness Index; Age Distribution; Seasons; Male; Female; Pandemics; Respiratory Syncytial Virus, Human; Adolescent
PubMed: 38757287
DOI: 10.2807/1560-7917.ES.2024.29.20.2400269 -
Influenza and Other Respiratory Viruses May 2024Data available for RSV and influenza infections among children < 2 years in Mongolia are limited. We present data from four districts of Ulaanbaatar from April 2015...
BACKGROUND
Data available for RSV and influenza infections among children < 2 years in Mongolia are limited. We present data from four districts of Ulaanbaatar from April 2015 to June 2021.
METHODS
This study was nested in an enhanced surveillance project evaluating pneumococcal conjugate vaccine (PCV13) impact on the incidence of hospitalized lower respiratory tract infections (LRTIs). Our study was restricted to children aged < 2 years with arterial O saturation < 93% and children with radiological pneumonia. Nasopharyngeal (NP) swabs collected at admission were tested for RSV and influenza using qRT-PCR. NP swabs of all patients with radiological pneumonia and of a subset of randomly selected NP swabs were tested for S. pneumoniae (S.p.) by qPCR and for serotypes by culture and DNA microarray.
RESULTS
Among 5705 patients, 2113 (37.0%) and 386 (6.8%) had RSV and influenza infections, respectively. Children aged 2-6 months had a higher percentage of very severe RSV infection compared to those older than 6 months (42.2% versus 31.4%, p-value Fisher's exact = 0.001). S.p. carriage was detected in 1073/2281 (47.0%) patients. Among S.p. carriage cases, 363/1073 (33.8%) had S.p. and RSV codetection, and 82/1073 (7.6%) had S.p. and influenza codetection. S.p. codetection with RSV/influenza was not associated with more severe LRTIs, compared to only RSV/influenza cases.
CONCLUSION
In Mongolia, RSV is an important pathogen causing more severe LRTI in children under 6 months of age. Codetection of RSV or influenza virus and S.p. was not associated with increased severity.
Topics: Humans; Mongolia; Respiratory Syncytial Virus Infections; Infant; Influenza, Human; Female; Male; Respiratory Syncytial Virus, Human; Child, Preschool; Nasopharynx; Infant, Newborn; Incidence; Hospitalization; Streptococcus pneumoniae; Respiratory Tract Infections
PubMed: 38757258
DOI: 10.1111/irv.13303 -
Indian Journal of Medical Ethics 2024As the world grapples with the constant threat of new pathogens, the role of government oversight in research and response efforts has become a topic of considerable...
As the world grapples with the constant threat of new pathogens, the role of government oversight in research and response efforts has become a topic of considerable debate in the academic community. In the recently released "SOP [standard operating procedure] for Nipah virus research in Kerala for studies involving human participants / human samples" by the Government of Kerala, the SOP, apart from administrative permission, requires the proposal to be cleared by the Institutional Research Committee at a Government Medical College, and the inclusion of an investigator from a government institution [1]. In these challenging times, it is crucial to weigh the pros and cons of stringent administrative controls to ensure an effective and ethical approach to tackling emerging infectious diseases.
Topics: Humans; Communicable Diseases, Emerging; India; Biomedical Research; Government Regulation; Nipah Virus; Henipavirus Infections; Ethics Committees, Research
PubMed: 38755764
DOI: 10.20529/IJME.2024.016 -
Nature Communications May 2024Cell plasticity theoretically extends to all possible cell types, but naturally decreases as cells differentiate, whereas injury-repair re-engages the developmental...
Cell plasticity theoretically extends to all possible cell types, but naturally decreases as cells differentiate, whereas injury-repair re-engages the developmental plasticity. Here we show that the lung alveolar type 2 (AT2)-specific transcription factor (TF), CEBPA, restricts AT2 cell plasticity in the mouse lung. AT2 cells undergo transcriptional and epigenetic maturation postnatally. Without CEBPA, both neonatal and mature AT2 cells reduce the AT2 program, but only the former reactivate the SOX9 progenitor program. Sendai virus infection bestows mature AT2 cells with neonatal plasticity where Cebpa mutant, but not wild type, AT2 cells express SOX9, as well as more readily proliferate and form KRT8/CLDN4+ transitional cells. CEBPA promotes the AT2 program by recruiting the lung lineage TF NKX2-1. The temporal change in CEBPA-dependent plasticity reflects AT2 cell developmental history. The ontogeny of AT2 cell plasticity and its transcriptional and epigenetic mechanisms have implications in lung regeneration and cancer.
Topics: Animals; Cell Plasticity; Mice; Alveolar Epithelial Cells; Thyroid Nuclear Factor 1; SOX9 Transcription Factor; CCAAT-Enhancer-Binding Proteins; Cell Differentiation; Epigenesis, Genetic; Mice, Inbred C57BL; Lung Injury; Regeneration; Sendai virus; Cell Proliferation; Mice, Knockout; Lung
PubMed: 38755149
DOI: 10.1038/s41467-024-48632-3 -
Nature Communications May 2024Human Ebola virus (EBOV) outbreaks caused by persistent EBOV infection raises questions on the role of zoonotic spillover in filovirus epidemiology. To characterise...
Human Ebola virus (EBOV) outbreaks caused by persistent EBOV infection raises questions on the role of zoonotic spillover in filovirus epidemiology. To characterise filovirus zoonotic exposure, we collected cross-sectional serum samples from bushmeat hunters (n = 498) in Macenta Prefecture Guinea, adjacent to the index site of the 2013 EBOV-Makona spillover event. We identified distinct immune signatures (20/498, 4.0%) to multiple EBOV antigens (GP, NP, VP40) using stepwise ELISA and Western blot analysis and, live EBOV neutralisation (5/20; 25%). Using comparative serological data from PCR-confirmed survivors of the 2013-2016 EBOV outbreak, we demonstrated that most signatures (15/20) were not plausibly explained by prior EBOV-Makona exposure. Subsequent data-driven modelling of EBOV immunological outcomes to remote-sensing environmental data also revealed consistent associations with intact closed canopy forest. Together our findings suggest exposure to other closely related filoviruses prior to the 2013-2016 West Africa epidemic and highlight future surveillance priorities.
Topics: Humans; Animals; Guinea; Ebolavirus; Hemorrhagic Fever, Ebola; Adult; Male; Antibodies, Viral; Middle Aged; Zoonoses; Female; Cross-Sectional Studies; Disease Outbreaks; Young Adult; Aged; Enzyme-Linked Immunosorbent Assay; Viral Zoonoses; Antigens, Viral
PubMed: 38755147
DOI: 10.1038/s41467-024-48587-5 -
Journal of Autoimmunity Jun 2024Neonatal Fc receptor (FcRn) recycles immunoglobulin G, and inhibition of FcRn is used clinically for treatment of autoimmune diseases. In this work, using the vesicular...
Neonatal Fc receptor (FcRn) recycles immunoglobulin G, and inhibition of FcRn is used clinically for treatment of autoimmune diseases. In this work, using the vesicular stomatitis virus (VSV) mouse infection model system, we determined the role of FcRn during virus infection. While induction of neutralizing antibodies and long-term protection of these antibodies was hardly affected in FcRn deficient mice, FcRn deficiency limited the amount of natural IgG (VSV-specific) antibodies. Lack of natural antibodies (nAbs) limited early control of VSV in macrophages, accelerated propagation of virus in several organs, led to the spread of VSV to the neural tissue resulting in fatal outcomes. Adoptive transfer of natural IgG into FcRn deficient mice limited early propagation of VSV in FcRn deficient mice and enhanced survival of FcRn knockout mice. In line with this, vaccination of FcRn mice with very low dose of VSV prior to infection similarly prevented death after infection. In conclusion we determined the importance of nAbs during VSV infection. Lack of FcRn limited nAbs and thereby enhanced the susceptibility to virus infection.
Topics: Animals; Mice; Immunoglobulin G; Receptors, Fc; Mice, Knockout; Histocompatibility Antigens Class I; Vesicular Stomatitis; Antibodies, Viral; Antibodies, Neutralizing; Vesiculovirus; Vesicular stomatitis Indiana virus; Disease Models, Animal; Adoptive Transfer; Macrophages; Mice, Inbred C57BL
PubMed: 38754237
DOI: 10.1016/j.jaut.2024.103230 -
Influenza and Other Respiratory Viruses May 2024Respiratory syncytial virus (RSV) is a substantial cause of infant morbidity and mortality due to seasonal peaks of bronchiolitis across the United States. Clinical and...
Geographic Progression of Infant Respiratory Syncytial Virus Associated Bronchiolitis Across the United States Before and Since the Onset of COVID-19: Results From Four Health Systems, 2015-2023.
BACKGROUND
Respiratory syncytial virus (RSV) is a substantial cause of infant morbidity and mortality due to seasonal peaks of bronchiolitis across the United States. Clinical and viral surveillance plays a pivotal role in helping hospital systems prepare for expected surges in RSV bronchiolitis. Existing surveillance efforts have shown a geographic pattern of RSV positivity across the United States, with cases typically starting in the southeast and spreading north and west. Public health measures implemented due to the COVID-19 pandemic disrupted viral transmission across the nation and altered the expected seasonality of RSV. The impact of these changes on the geographic progression of infant RSV bronchiolitis across the United States has not been described.
METHODS
Here, we used clinical and viral surveillance data from four health care systems located in different regions of the United States to describe the geographic progression of infant RSV bronchiolitis across the country from 2015 to 2023.
RESULTS
Prior to widespread circulation of SARS-CoV-2, infant RSV bronchiolitis followed an established geographic pattern associated with seasonal epidemics originating in Florida and spreading north (North Carolina and New York) and later westward (Nevada). Although public health and social measures implemented during the COVID-19 pandemic disrupted the seasonality of RSV disease, infant RSV bronchiolitis epidemics progressed across the nation in a pattern identical to the prepandemic era.
CONCLUSIONS
Our findings highlight the importance of ongoing clinical and viral surveillance to optimally track the onset of RSV epidemics and allow health care systems to prepare for expected RSV bronchiolitis surges.
Topics: Humans; COVID-19; United States; Infant; Respiratory Syncytial Virus Infections; Bronchiolitis; Respiratory Syncytial Virus, Human; Seasons; SARS-CoV-2; Infant, Newborn; Female; Male
PubMed: 38751165
DOI: 10.1111/irv.13298 -
Breast Cancer Research : BCR May 2024Metastatic breast cancer is a leading cause of cancer death in woman. Current treatment options are often associated with adverse side effects and poor outcomes,...
BACKGROUND
Metastatic breast cancer is a leading cause of cancer death in woman. Current treatment options are often associated with adverse side effects and poor outcomes, demonstrating the need for effective new treatments. Immunotherapies can provide durable outcomes in many cancers; however, limited success has been achieved in metastatic triple negative breast cancer. We tested whether combining different immunotherapies can target metastatic triple negative breast cancer in pre-clinical models.
METHODS
Using primary and metastatic 4T1 triple negative mammary carcinoma models, we examined the therapeutic effects of oncolytic vesicular stomatitis virus (VSVΔM51) engineered to express reovirus-derived fusion associated small transmembrane proteins p14 (VSV-p14) or p15 (VSV-p15). These viruses were delivered alone or in combination with natural killer T (NKT) cell activation therapy mediated by adoptive transfer of α-galactosylceramide-loaded dendritic cells.
RESULTS
Treatment of primary 4T1 tumors with VSV-p14 or VSV-p15 alone increased immunogenic tumor cell death, attenuated tumor growth, and enhanced immune cell infiltration and activation compared to control oncolytic virus (VSV-GFP) treatments and untreated mice. When combined with NKT cell activation therapy, oncolytic VSV-p14 and VSV-p15 reduced metastatic lung burden to undetectable levels in all mice and generated immune memory as evidenced by enhanced in vitro recall responses (tumor killing and cytokine production) and impaired tumor growth upon rechallenge.
CONCLUSION
Combining NKT cell immunotherapy with enhanced oncolytic virotherapy increased anti-tumor immune targeting of lung metastasis and presents a promising treatment strategy for metastatic breast cancer.
Topics: Animals; Female; Mice; Natural Killer T-Cells; Oncolytic Virotherapy; Humans; Cell Line, Tumor; Oncolytic Viruses; Immunotherapy; Vesicular stomatitis Indiana virus; Triple Negative Breast Neoplasms; Combined Modality Therapy; Neoplasm Metastasis; Vesiculovirus; Dendritic Cells; Breast Neoplasms; Disease Models, Animal
PubMed: 38750591
DOI: 10.1186/s13058-024-01818-5