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American Journal of Transplantation :... Jun 2024Solid organ transplant recipients require ongoing immunosuppression to prevent acute rejection, which puts them at risk of opportunistic infections. Viral infections are... (Review)
Review
Solid organ transplant recipients require ongoing immunosuppression to prevent acute rejection, which puts them at risk of opportunistic infections. Viral infections are particularly challenging to prevent and treat as many establish latency and thus cannot be eliminated, whereas targets for small molecule antiviral medications are limited. Resistance to antivirals and unacceptable toxicity also complicate treatment. Virus-specific T cell therapies aim to restore host-specific immunity to opportunistic viruses that is lacking due to ongoing immunosuppressive therapy. This minireview will provide a state-of-the-art update of the current virus-specific T cell pipeline and translational research that is likely to lead to further treatment options for viral infections in solid organ transplant recipients.
PubMed: 38857784
DOI: 10.1016/j.ajt.2024.05.019 -
PLOS Global Public Health 2024The COVID-19 pandemic had an unprecedented impact on global mental health and well-being, including across the Asia-Pacific. Efforts to mitigate virus spread led to...
The COVID-19 pandemic had an unprecedented impact on global mental health and well-being, including across the Asia-Pacific. Efforts to mitigate virus spread led to far-reaching disruption in the delivery of health and social services. In response, there was a rapid shift to the use of digital mental health (DMH) approaches. Though these technologies helped to improve access to care for many, there was also substantial risk of access barriers leading to increased inequities in access to mental health care, particularly among at-risk and equity-deserving populations. The objective of this study was to conduct a needs assessment and identify priorities related to equitable DMH access among at-risk and equity-deserving populations in the Asia Pacific region during the first year of the COVID-19 pandemic. The study consisted of a modified Delphi consensus methodology including two rounds of online surveys and online consultations with stakeholders from across the region. Study participants included policy makers, clinicians and service providers, and people with lived experience of mental health conditions. Results demonstrate that vulnerabilities to negative mental health impacts and access barriers were compounded during the pandemic. Access barriers included a lack of linguistically and culturally appropriate DMH options, low mental health literacy and poor access to technological infrastructure and devices, low levels of awareness and trust of DMH options, and lack of policies and guidelines to support effective and equitable delivery of DMH. Recommendations to improve equitable access include ensuring that diverse people with lived experience are engaged in research, co-design and policy development, the development and implementation of evidence-based and equity-informed guidelines and frameworks, clear communication about DMH evidence and availability, and the integration of DMH into broader health systems. Study results can inform the development and implementation of equitable DMH as its use becomes more widespread across health systems.
PubMed: 38857265
DOI: 10.1371/journal.pgph.0002661 -
BioRxiv : the Preprint Server For... Jun 2024Targeted protein degradation has been widely adopted as a new approach to eliminate both established and previously recalcitrant therapeutic targets. Here we report the...
Targeted protein degradation has been widely adopted as a new approach to eliminate both established and previously recalcitrant therapeutic targets. Here we report the development of small molecule degraders of the envelope (E) protein of dengue virus. We developed two classes of bivalent E-degraders, linking two previously reported E-binding small molecules, GNF-2 and CVM-2-12-2, to a glutarimide-based recruiter of the CRL4 ligase to effect proteosome-mediated degradation of the E protein. ZXH-2-107 (based on GNF-2) is an E degrader with ABL inhibition while ZXH-8-004 (based on CVM-2-12-2) is a selective and potent E-degrader. These two compounds provide proof-of-concept that difficult-to-drug targets such as a viral envelope protein can be effectively eliminated using a bivalent degrader and provide starting points for the future development of a new class antiviral drugs.
PubMed: 38854003
DOI: 10.1101/2024.06.01.596987 -
Virus Research Aug 2024The human JC polyomavirus (JCV) is a widespread, neurotropic, opportunistic pathogen responsible for progressive multifocal leukoencephalopathy (PML) as well as other...
The human JC polyomavirus (JCV) is a widespread, neurotropic, opportunistic pathogen responsible for progressive multifocal leukoencephalopathy (PML) as well as other diseases in immunosuppressed individuals, including granule cell neuronopathy, JCV-associated nephropathy, encephalitis, and meningitis in rare cases. JCV classification is still unclear, where the ICTV (International Committee on Taxonomy of Viruses) has grouped all the strains into human polyomavirus 2, with no classification on clade and subclade levels. Therefore, JCV strains were previously classified using different genomic regions, e.g., full-length, VP1, and the V-T intergenic region etc., and the strains were grouped into several types related to various geographic locations and human ethnicities. However, neither of these classifications and nomenclature contemplates all the groups described so far. Herein, we evaluated all the available full-length coding genomes, VP1, and large T antigen nucleotide sequences of JCV reported during 1993-2023 and classified them into four major phylogenetic clades, i.e., GI-GIV, where GI is further grouped into two types GI.1 and GI.2 with five sub-clades each (GI.1/GI.2 a-e), GII into three (GII a-c), GIII as a separate clade, and GIV into seven sub-clades (GIV a-g). Similarly, the phylogeographic network analysis indicated four major clusters corresponding to GI-GIV clades, each with multiple subclusters and mutational sub-branches corresponding to the subclades. GI and GIV clusters are connected via GI.1-e reported from Europe and America, GII, GIII and GIV clusters are connected by GII-b and GII-c strains reported from Africa, while GIV cluster strains are connected to the Russia-Italy JCV haplotype. Furthermore, we identified JCV-variant-GS/B-Germany-1997 (GenBank ID: AF004350.1) as an inter-genotype recombinant having major and minor parents in the GI.1-e and GII-a clades, respectively. Additionally, the amino acid variability analysis revealed high entropy across all proteins. The large T antigen exhibited the highest variability, while the small t antigen showed the lowest variability. Our phylogenetic and phylogeographic analyses provide a new approach to genotyping and sub-genotyping and present a comprehensive classification system of JCV strains based on their genetic characteristics and geographic distribution, while the genetic recombination and amino acid variability can help identify pathogenicity and develop effective preventive and control measures against JCV infections.
Topics: JC Virus; Phylogeography; Humans; Phylogeny; Genome, Viral; Leukoencephalopathy, Progressive Multifocal; Polyomavirus Infections; Genetic Variation; Cluster Analysis
PubMed: 38848817
DOI: 10.1016/j.virusres.2024.199414 -
Biochimica Et Biophysica Acta.... Aug 2024This study aims to investigate the role of claudin-5 (Cldn5) in cardiac structural integrity. Proteomic analysis was performed to screen the protein profiles in enlarged...
This study aims to investigate the role of claudin-5 (Cldn5) in cardiac structural integrity. Proteomic analysis was performed to screen the protein profiles in enlarged left atrium from atrial fibrillation (AF) patients. Cldn5 shRNA adeno-associated virus (AAV) or siRNA was injected into the mouse left ventricle or added into HL1 cells respectively to knockdown Cldn5 in cardiomyocytes to observe whether the change of Cldn5 influences cardiac morphology and function, and affects those protein expressions stem from the proteomic analysis. Mitochondrial density and membrane potential were also measured by Mitotracker staining and JC-1 staining under the confocal microscope in HL1 cells. Cldn5 was reduced in cardiomyocytes from the left atrial appendage of AF patients compared to non-AF donors. Proteomic analysis showed 83 proteins were less abundant and 102 proteins were more abundant in AF patients. KEGG pathway analysis showed less abundant CACNA2D2, CACNB2, MYL2 and MAP6 were highly associated with dilated cardiomyopathy. Cldn5 shRNA AAV injection caused severe cardiac atrophy, dilation and myocardial dysfunction in mice. The decreases in mitochondrial numbers and mitochondrial membrane potentials in HL1 cells were observed after Cldn5 knockdown. We demonstrated for the first time the mechanism of Cldn5 downregulation-induced myocyte atrophy and myocardial dysfunction might be associated with the downregulation of CACNA2D2, CACNB2, MYL2 and MAP6, and mitochondrial dysfunction in cardiomyocytes.
Topics: Animals; Female; Humans; Male; Mice; Atrial Fibrillation; Cell Line; Claudin-5; Membrane Potential, Mitochondrial; Mice, Inbred C57BL; Myocytes, Cardiac; Proteomics
PubMed: 38838411
DOI: 10.1016/j.bbadis.2024.167274 -
CEN Case Reports Jun 2024Progressive multifocal leukoencephalopathy (PML), a severe demyelinating disease of the central nervous system, is caused by the reactivation of the polyomavirus JC...
Progressive multifocal leukoencephalopathy (PML), a severe demyelinating disease of the central nervous system, is caused by the reactivation of the polyomavirus JC virus (JCV). It favors the cerebrum and typically occurs in patients with immunodeficiencies, with a progressive course and fatal outcome in the majority of cases. However, the cerebellar form of PML, characterized by isolated posterior fossa lesions, such as those in the cerebellum or brainstem at disease onset, is rare, and reports of its occurrence in peritoneal dialysis (PD) patients are lacking. In this paper, we describe a rare case of a cerebellar form of PML in a PD patient. A 64-year-old man undergoing PD was referred to our hospital for anorexia, nausea, and vomiting in the past month. He had finger-to-nose test abnormalities, gaze-directed nystagmus, and scanning speech. He was diagnosed with the cerebellar form of PML based on his progressive cerebellar symptoms, the typical magnetic resonance imaging findings, and the presence of JCV-DNA in the cerebrospinal fluid polymerase chain reaction test. He developed nocturnal delirium, aggravated disquiet, and died of pneumonia on the 69th day. Clinicians should consider the cerebellar form of PML as a differential diagnosis if PD patients develop progressive cerebellar symptoms.
PubMed: 38824484
DOI: 10.1007/s13730-024-00896-w -
EBioMedicine Jun 2024Tight-fitting masks and respirators, in manikin studies, improved aerosol source control compared to loose-fitting masks. Whether this translates to humans is not known.
Relative efficacy of masks and respirators as source control for viral aerosol shedding from people infected with SARS-CoV-2: a controlled human exhaled breath aerosol experimental study.
BACKGROUND
Tight-fitting masks and respirators, in manikin studies, improved aerosol source control compared to loose-fitting masks. Whether this translates to humans is not known.
METHODS
We compared efficacy of masks (cloth and surgical) and respirators (KN95 and N95) as source control for SARS-CoV-2 viral load in exhaled breath of volunteers with COVID-19 using a controlled human experimental study. Volunteers (N = 44, 43% female) provided paired unmasked and masked breath samples allowing computation of source-control factors.
FINDINGS
All masks and respirators significantly reduced exhaled viral load, without fit tests or training. A duckbill N95 reduced exhaled viral load by 98% (95% CI: 97%-99%), and significantly outperformed a KN95 (p < 0.001) as well as cloth and surgical masks. Cloth masks outperformed a surgical mask (p = 0.027) and the tested KN95 (p = 0.014).
INTERPRETATION
These results suggest that N95 respirators could be the standard of care in nursing homes and healthcare settings when respiratory viral infections are prevalent in the community and healthcare-associated transmission risk is elevated.
FUNDING
Defense Advanced Research Projects Agency, National Institute of Allergy and Infectious Diseases, Centers for Disease Control and Prevention, the Bill & Melinda Gates Foundation, and The Flu Lab.
Topics: Humans; COVID-19; Female; Masks; SARS-CoV-2; Male; Viral Load; Adult; N95 Respirators; Middle Aged; Virus Shedding; Aerosols; Respiratory Aerosols and Droplets; Exhalation; Breath Tests
PubMed: 38821778
DOI: 10.1016/j.ebiom.2024.105157 -
ELife May 2024Nonstructural protein 5 (Nsp5) is the main protease of SARS-CoV-2 that cleaves viral polyproteins into individual polypeptides necessary for viral replication. Here, we...
Nonstructural protein 5 (Nsp5) is the main protease of SARS-CoV-2 that cleaves viral polyproteins into individual polypeptides necessary for viral replication. Here, we show that Nsp5 binds and cleaves human tRNA methyltransferase 1 (TRMT1), a host enzyme required for a prevalent post-transcriptional modification in tRNAs. Human cells infected with SARS-CoV-2 exhibit a decrease in TRMT1 protein levels and TRMT1-catalyzed tRNA modifications, consistent with TRMT1 cleavage and inactivation by Nsp5. Nsp5 cleaves TRMT1 at a specific position that matches the consensus sequence of SARS-CoV-2 polyprotein cleavage sites, and a single mutation within the sequence inhibits Nsp5-dependent proteolysis of TRMT1. The TRMT1 cleavage fragments exhibit altered RNA binding activity and are unable to rescue tRNA modification in TRMT1-deficient human cells. Compared to wild-type human cells, TRMT1-deficient human cells infected with SARS-CoV-2 exhibit reduced levels of intracellular viral RNA. These findings provide evidence that Nsp5-dependent cleavage of TRMT1 and perturbation of tRNA modification patterns contribute to the cellular pathogenesis of SARS-CoV-2 infection.
Topics: Humans; Coronavirus 3C Proteases; COVID-19; HEK293 Cells; Proteolysis; RNA, Transfer; SARS-CoV-2; tRNA Methyltransferases; Viral Nonstructural Proteins; Virus Replication
PubMed: 38814682
DOI: 10.7554/eLife.90316 -
Microbial Pathogenesis Jul 2024Cimicifugae rhizoma is a traditional Chinese herbal medicine in China, and modern pharmacological research showed that it has obvious antiviral activity. Many...
Cimicifugae rhizoma is a traditional Chinese herbal medicine in China, and modern pharmacological research showed that it has obvious antiviral activity. Many polysaccharides have been proved to have immune enhancement and antiviral activity, but there are few studies on the biological activity of Cimicifuga rhizoma polysaccharide (CRP). The aim was to explore the character of CRP and its effects on improving immune activity and inhibiting transmissible gastroenteritis virus (TGEV). The monosaccharide composition, molecular weight, fourier transform infrared spectra and electron microscopy analysis of CRP was measured. The effect of CRP on immune activity in lymphocytes and RAW264.7 cells were studied by colorimetry, FITC-OVA fluorescent staining and ELISA. The effect of CRP on TGEV-infected PK-15 cells was determined using Real-time PCR, Hoechst fluorescence staining, trypan blue staining, acridine orange staining, Annexin V-FITC/PI fluorescent staining, DCFH-DA loading probe, and JC-1 staining. Network pharmacology was used to predict the targets of CRP in enhancing immunity and anti-TGEV, and molecular docking was used to further analyze the binding mode between CPR and core targets. The results showed that CRP was mainly composed of glucose and galactose, and its molecular weight was 64.28 kDa. The content of iNOS and NO in CRP group were significantly higher than the control group. CRP (125 and 62.5 μg/mL) could significantly enhance the phagocytic capacity of RAW264.7 cells, and imprive the content of IL-1β content compared with control group. 250 μg/mL of CRP possessed the significant inhibitory effect on TGEV, which could significantly reduce the apoptosis compared to TGVE group and inhibit the decrease in mitochondrial membrane potential compared to TGVE group. The mRNA expression of TGEV N gene in CRP groups was significantly lower than TGEV group. PPI showed that the core targets of immune-enhancing were AKT1, MMP9, HSP90AA1, etc., and the core targets of TGE were CASP3, MMP9, EGFR, etc. Molecular docking show that CRP has binding potential with target. These results indicated that CRP possessed the better immune enhancement effect and anti-TGEV activity.
Topics: Animals; Mice; Polysaccharides; Molecular Docking Simulation; RAW 264.7 Cells; Transmissible gastroenteritis virus; Antiviral Agents; Rhizome; Interleukin-1beta; Molecular Weight; Nitric Oxide Synthase Type II; Cell Line; Lymphocytes; Apoptosis; Drugs, Chinese Herbal; Spectroscopy, Fourier Transform Infrared; Monosaccharides; Nitric Oxide; Immunologic Factors
PubMed: 38810768
DOI: 10.1016/j.micpath.2024.106719 -
ELife May 2024Human H3N2 influenza viruses are subject to rapid antigenic evolution which translates into frequent updates of the composition of seasonal influenza vaccines. Despite...
Human H3N2 influenza viruses are subject to rapid antigenic evolution which translates into frequent updates of the composition of seasonal influenza vaccines. Despite these updates, the effectiveness of influenza vaccines against H3N2-associated disease is suboptimal. Seasonal influenza vaccines primarily induce hemagglutinin-specific antibody responses. However, antibodies directed against influenza neuraminidase (NA) also contribute to protection. Here, we analysed the antigenic diversity of a panel of N2 NAs derived from human H3N2 viruses that circulated between 2009 and 2017. The antigenic breadth of these NAs was determined based on the NA inhibition (NAI) of a broad panel of ferret and mouse immune sera that were raised by infection and recombinant N2 NA immunisation. This assessment allowed us to distinguish at least four antigenic groups in the N2 NAs derived from human H3N2 viruses that circulated between 2009 and 2017. Computational analysis further revealed that the amino acid residues in N2 NA that have a major impact on susceptibility to NAI by immune sera are in proximity of the catalytic site. Finally, a machine learning method was developed that allowed to accurately predict the impact of mutations that are present in our N2 NA panel on NAI. These findings have important implications for the renewed interest to develop improved influenza vaccines based on the inclusion of a protective NA antigen formulation.
Topics: Neuraminidase; Influenza A Virus, H3N2 Subtype; Humans; Animals; Ferrets; Antigens, Viral; Mice; Influenza, Human; Antibodies, Viral; Influenza Vaccines; Antigenic Variation; Viral Proteins; Orthomyxoviridae Infections
PubMed: 38805550
DOI: 10.7554/eLife.90782