The raging COVID-19 pandemic caused by SARS-CoV-2 has so far claimed the lives of 7 million people and continues to infect many more. Further, virus evolution has caused mutations that have compromised public health interventions like vaccination regimes and monoclonal antibody and convalescent sera treatments. In response, unprecedented large-scale whole genome viral surveillance approaches have been devised to keep track of the evolution and transmission patterns of the virus within and across populations.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
March 2025
Platelets, known for maintaining blood balance, also participate in antimicrobial defense. Upon severeacute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, platelets become hyperactivated, releasing molecules such as cytokines, granule contents, and bioactive lipids. The key effector biolipids produced by platelets include 12-hydroxyeicosatetraenoic acid (12-HETE) and 12-hydroxyeicosatrienoic acid (12-HETrE), produced by 12-lipoxygenase (12-LOX), and prostaglandins and thromboxane, produced by cyclooxygenase-1.
View Article and Find Full Text PDFEpidemiological investigations consistently demonstrate an overrepresentation of the elderly in COVID-19 hospitalizations and fatalities, making the advanced age as a major predictor of disease severity. Despite this, a comprehensive understanding of the cellular and molecular mechanisms explaining how old age represents a major risk factor remain elusive. To investigate this, we compared SARS-CoV-2 infection outcomes in young adults (2 months) and geriatric (15-22 months) mice.
View Article and Find Full Text PDFThe Coronavirus Disease 2019 (COVID-19), caused by virus SARS-CoV-2, is characterized by massive inflammation and immune system imbalance. Despite the implementation of vaccination protocols, the accessibility of treatment remains uneven. Furthermore, the persistent threat of new variants underscores the urgent need for expanded research into therapeutic options for SARS-CoV-2.
View Article and Find Full Text PDFMegakaryocytes (MKs), integral to platelet production, predominantly reside in the bone marrow (BM) and undergo regulated fragmentation within sinusoid vessels to release platelets into the bloodstream. Inflammatory states and infections influence MK transcription, potentially affecting platelet functionality. Notably, COVID-19 has been associated with altered platelet transcriptomes.
View Article and Find Full Text PDFThe scientific and medical community faced an unprecedented global health hazard that led to nearly 7 million deaths attributable to the rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In spite of the development of efficient vaccines against SARS-CoV-2, many people remain at risk of developing severe symptoms as the virus continues to spread without beneficial patient therapy. The hyper-inflammatory response to SARS-CoV-2 infection progressing to acute respiratory distress syndrome remains an unmet medical need for improving patient care.
View Article and Find Full Text PDFThe persistence of SARS-CoV-2 despite the development of vaccines and a degree of herd immunity is partly due to viral evolution reducing vaccine and treatment efficacy. Serial infections of wild-type (WT) SARS-CoV-2 in Balb/c mice yield mouse-adapted strains with greater infectivity and mortality. We investigate if passaging unmodified B.
View Article and Find Full Text PDFA vaccine candidate to SARS-CoV-2 was constructed by coupling the viral receptor binding domain (RBD) to the surface of the papaya mosaic virus (PapMV) nanoparticle (nano) to generate the RBD-PapMV vaccine. Immunization of mice with the coupled RBD-PapMV vaccine enhanced the antibody titers and the T-cell mediated immune response directed to the RBD antigen as compared to immunization with the non-coupled vaccine formulation (RBD + PapMV nano). Anti-RBD antibodies, generated in vaccinated animals, neutralized SARS-CoV-2 infection in vitro against the ancestral, Delta and the Omicron variants.
View Article and Find Full Text PDFFront Immunol
July 2022
Coronavirus disease 19 (COVID-19) is the clinical manifestation of severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) infection. A hallmark of COVID-19 is a lung inflammation characterized by an abundant leukocyte infiltrate, elevated levels of cytokines/chemokines, lipid mediators of inflammation (LMI) and microthrombotic events. Animal models are useful for understanding the pathophysiological events leading to COVID-19.
View Article and Find Full Text PDFPlatelets are hyperactivated in coronavirus disease 2019 (COVID-19). However, the mechanisms promoting platelet activation by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are not well understood. This may be due to inherent challenges in discriminating the contribution of viral vs host components produced by infected cells.
View Article and Find Full Text PDFJ Allergy Clin Immunol
August 2021
Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can lead to a variety of clinical outcomes, ranging from the absence of symptoms to severe acute respiratory disease and ultimately death. A feature of patients with severe coronavirus disease 2019 (COVID-19) is the abundance of inflammatory cytokines in the blood. Elevated levels of cytokines are predictive of infection severity and clinical outcome.
View Article and Find Full Text PDFSevere acute respiratory syndrome coronavirus 2 is responsible for coronavirus disease 2019 (COVID-19). While COVID-19 is often benign, a subset of patients develops severe multilobar pneumonia that can progress to an acute respiratory distress syndrome. There is no cure for severe COVID-19 and few treatments significantly improved clinical outcome.
View Article and Find Full Text PDFNeurotensin (NT) is a tridecapeptide displaying interesting antinociceptive properties through its action on its receptors, NTS1 and NTS2. Neurotensin-like compounds have been shown to exert better antinociceptive properties than morphine at equimolar doses. In this article, we characterized the molecular effects of a novel neurotensin (8-13) (NT(8-13)) analog containing an unnatural amino acid.
View Article and Find Full Text PDFNeurotensin (NT) exerts naloxone-insensitive antinociceptive action through its binding to both NTS and NTS receptors and NT analogs provide stronger pain relief than morphine on a molecular basis. Here, we examined the analgesic/adverse effect profile of a new NT(8-13) derivative denoted JMV2009, in which the Pro residue was substituted by a silicon-containing unnatural amino acid silaproline. We first report the synthesis and in vitro characterization (receptor-binding affinity, functional activity and stability) of JMV2009.
View Article and Find Full Text PDFApproximately 1% of people worldwide carry a copy of the human herpesvirus 6A or 6B (HHV-6A/B) in every cell of their body. This condition is referred to as inherited chromosomally integrated HHV-6A/B (iciHHV-6A/B). The mechanisms leading to iciHHV-6A/B chromosomal integration are yet to be identified.
View Article and Find Full Text PDFHuman herpesviruses 6A and 6B (HHV-6A and HHV-6B) are human viruses capable of chromosomal integration. Approximately 1% of the human population carries one copy of HHV-6A/B integrated into every cell in their body, referred to as inherited chromosomally integrated human herpesvirus 6A/B (iciHHV-6A/B). Whether iciHHV-6A/B is transcriptionally active and how it shapes the immunological response are still unclear.
View Article and Find Full Text PDFFront Microbiol
June 2019
Human herpesvirus-6A (HHV-6A) and 6B (HHV-6B) are two closely related betaherpesviruses that are associated with various diseases including seizures and encephalitis. The HHV-6A/B genomes have been shown to be present in an integrated state in the telomeres of latently infected cells. In addition, integration of HHV-6A/B in germ cells has resulted in individuals harboring this inherited chromosomally integrated HHV-6A/B (iciHHV-6) in every cell of their body.
View Article and Find Full Text PDFEM66 is a peptide derived from the chromogranin, secretogranin II (SG-II). Recent findings in mice indicate that EM66 is a novel anorexigenic neuropeptide that regulates hypothalamic feeding behavior, at least in part, by activating the POMC neurons of the arcuate nucleus. The present study aimed to investigate the mechanism of action of EM66 in the control of feeding behavior and, more specifically, its potential interactions with the NPY and POMC systems in rat.
View Article and Find Full Text PDFCancer Epidemiol Biomarkers Prev
March 2017
Inherited chromosomally integrated human herpesvirus 6 (iciHHV-6) is a condition observed in approximately 1% of the population. Whether such a genetic alteration predisposes to cancer development in currently unknown. Two studies were conducted to determine whether iciHHV-6 is associated with cancer development.
View Article and Find Full Text PDFInherited chromosomally integrated human herpesvirus-6 (iciHHV-6) results in the germ-line transmission of the HHV-6 genome. Every somatic cell of iciHHV-6+ individuals contains the HHV-6 genome integrated in the telomere of chromosomes. Whether having iciHHV-6 predisposes humans to diseases remains undefined.
View Article and Find Full Text PDFHuman herpesvirus-6A (HHV-6A) and HHV-6B integrate their genomes into the telomeres of human chromosomes, however, the mechanisms leading to integration remain unknown. HHV-6A/B encode a protein that has been proposed to be involved in integration termed U94, an ortholog of adeno-associated virus type 2 (AAV-2) Rep68 integrase. In this report, we addressed whether purified recombinant maltose-binding protein (MBP)-U94 fusion proteins of HHV-6A/B possess biological functions compatible with viral integration.
View Article and Find Full Text PDFContext: Anorexia nervosa (AN) presents an adaptive appetite regulating profile including high levels of ghrelin and 26RFa (orexigenic) and low levels of leptin and PYY (anorexigenic). However, this adaptive mechanism is not effective in promoting food intake. The NPY/proopiomelanocortin (POMC) system plays a crucial role in the regulation of feeding behavior as NPY is the most potent orexigenic neuropeptide identified so far and as the POMC-derived peptide α-MSH drastically reduces food intake, and this peptidergic system has not been thoroughly studied in AN.
View Article and Find Full Text PDFHuman herpesvirus 6B (HHV-6B) is a ubiquitous pathogen with frequent reactivation observed in immunocompromised patients such as BM transplant (BMT) recipients. Adoptive immunotherapy is a promising therapeutic avenue for the treatment of opportunistic infections, including herpesviruses. While T-cell immunotherapy can successfully control CMV and EBV reactivations in BMT recipients, such therapy is not available for HHV-6 infections, in part due to a lack of identified protective CD8(+) T-cell epitopes.
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