Immune responses associated with mpox viral clearance in men with and without HIV in Spain: a multisite, observational, prospective cohort study.

Background: Since the emergence of the global mpox outbreak in May, 2022, more than 90 000 cases have been diagnosed across 110 countries, disproportionately affecting people with HIV. The durability of mpox-specific immunity is unclear and reinfections have been reported. We aimed to compare mpox immune responses up to 6 months after diagnosis in participants with and without HIV and assess their effect on disease severity and viral clearance dynamics.

Preclinical development of humanized monoclonal antibodies against CD169 as a broad antiviral therapeutic strategy.

New therapies to treat or prevent viral infections are essential, as recently observed during the COVID-19 pandemic. Here, we propose a therapeutic strategy based on monoclonal antibodies that block the specific interaction between the host receptor Siglec-1/CD169 and gangliosides embedded in the viral envelope. Antibodies are an excellent option for treating infectious diseases based on their high specificity, strong targeting affinity, and relatively low toxicity.

Immunization with V987H-stabilized Spike glycoprotein protects K18-hACE2 mice and golden Syrian hamsters upon SARS-CoV-2 infection.

Safe and effective severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines are crucial to fight against the coronavirus disease 2019 pandemic. Most vaccines are based on a mutated version of the Spike glycoprotein [K986P/V987P (S-2P)] with improved stability, yield and immunogenicity. However, S-2P is still produced at low levels.

Plitidepsin as an Immunomodulator against Respiratory Viral Infections.

Plitidepsin is a host-targeted compound known for inducing a strong anti-SARS-CoV-2 activity, as well as for having the capacity of reducing lung inflammation. Because IL-6 is one of the main cytokines involved in acute respiratory distress syndrome, the effect of plitidepsin in IL-6 secretion in different in vitro and in vivo experimental models was studied. A strong plitidepsin-mediated reduction of IL-6 was found in human monocyte-derived macrophages exposed to nonproductive SARS-CoV-2.

Novel Spike-stabilized trimers with improved production protect K18-hACE2 mice and golden Syrian hamsters from the highly pathogenic SARS-CoV-2 Beta variant.

Most COVID-19 vaccines are based on the SARS-CoV-2 Spike glycoprotein (S) or their subunits. However, S shows some structural instability that limits its immunogenicity and production, hampering the development of recombinant S-based vaccines. The introduction of the K986P and V987P (S-2P) mutations increases the production and immunogenicity of the recombinant S trimer, suggesting that these two parameters are related.

β-Cyclodextrins as affordable antivirals to treat coronavirus infection.

The SARS-CoV-2 pandemic made evident that there are only a few drugs against coronavirus. Here we aimed to identify a cost-effective antiviral with broad spectrum activity and high safety profile. Starting from a list of 116 drug candidates, we used molecular modelling tools to rank the 44 most promising inhibitors.

induces trained immunity in vitro.

The COVID-19 pandemic posed a global health crisis, with new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants weakening vaccine-driven protection. Trained immunity could help tackle COVID-19 disease. Our objective was to analyze whether heat-killed (hkMm), an environmental mycobacterium, induces trained immunity and confers protection against SARS-CoV-2 infection.

Cyanovirin-N binds to select SARS-CoV-2 spike oligosaccharides outside of the receptor binding domain and blocks infection by SARS-CoV-2.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an enveloped positive stranded RNA virus which has caused the recent deadly pandemic called COVID-19. The SARS-CoV-2 virion is coated with a heavily glycosylated Spike glycoprotein which is responsible for attachment and entry into target cells. One, as yet unexploited strategy for preventing SARS-CoV-2 infections, is the targeting of the glycans on Spike.

Randomized clinical trial to assess the impact of oral intervention with cetylpyridinium chloride to reduce salivary SARS-CoV-2 viral load.

Aim: Aerosols released from the oral cavity help spread the SARS-CoV-2 virus. The use of a mouthwash formulated with an antiviral agent could reduce the viral load in saliva, helping to lower the spread of the virus. The aim of this study was to assess the efficacy of a mouthwash with 0.

Limited Humoral and Specific T-Cell Responses After SARS-CoV-2 Vaccination in PWH With Poor Immune Reconstitution.

Background: We analyzed humoral and cellular immune responses induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) messenger RNA (mRNA) vaccines in people with human immunodeficiency virus (HIV; PWH) who had CD4+ T-cell counts <200/µL (HIV<200 group).

Methods: This prospective cohort study included 58 PWH in the HIV<200 group, 36 with CD4+ T-cell counts >500/µL (HIV>500 group), and 33 HIV-1-negative controls (control group). Antibodies against the SARS-CoV-2 spike protein (anti-S immunoglobulin [Ig] G) and the receptor-binding domain (anti-RBD IgG) were quantified before and 4 weeks after the first and the second doses of BNT162b2 or mRNA-1273 (at week 8).

Role of Siglecs in viral infections: A double-edged sword interaction.

Sialic-acid-binding immunoglobulin-like lectins are cell surface immune receptors known as Siglecs that play a paramount role as modulators of immunity. In recent years, research has underscored how the underlaying biology of this family of receptors influences the outcome of viral infections. While Siglecs are needed to promote effective antiviral immune responses, they can also pave the way to viral dissemination within tissues.

Cetylpyridinium Chloride Mouthwash to Reduce Shedding of Infectious SARS-CoV-2: A Double-Blind Randomized Clinical Trial.

The airborne transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) via respiratory fluids and droplets suggests that mouthwashes containing substances with virucidal activity can help reduce viral spread. We conducted a multicenter, double-blind, placebo-controlled, randomized trial to assess the virucidal activity of cetylpyridinium chloride (CPC) mouthwashes. Outpatients who tested positive for SARS-CoV-2 infection with or without symptoms were randomized to perform washes and gargles for 1 min with 15 mL of either colored distilled water or 0.

Performance of SARS-CoV-2 Antigen-Detecting Rapid Diagnostic Tests for Omicron and Other Variants of Concern.

The SARS-CoV-2 antigen-detecting rapid diagnostic test (Ag-RDTs) is an easy-to-use diagnostic tool to identify the contagious individuals and reduce the new infections. However, to be effective, Ag-RDTs require the detection of distinct variants of concern (VOC) with high analytical sensitivity. Here, we found that the VOC diverge at the nucleocapsid protein used by four commercial Ag-RDTs for the viral detection.

Heterogeneous Infectivity and Pathogenesis of SARS-CoV-2 Variants Beta, Delta and Omicron in Transgenic K18-hACE2 and Wildtype Mice.

The emerging SARS-CoV-2 variants of concern (VOCs) may display enhanced transmissibility, more severity and/or immune evasion; however, the pathogenesis of these new VOCs in experimental SARS-CoV-2 models or the potential infection of other animal species is not completely understood. Here we infected K18-hACE2 transgenic mice with B.1, B.

Unraveling the antiviral activity of plitidepsin against SARS-CoV-2 by subcellular and morphological analysis.

The pandemic caused by the new coronavirus SARS-CoV-2 has made evident the need for broad-spectrum, efficient antiviral treatments to combat emerging and re-emerging viruses. Plitidepsin is an antitumor agent of marine origin that has also shown a potent pre-clinical efficacy against SARS-CoV-2. Plitidepsin targets the host protein eEF1A (eukaryotic translation elongation factor 1 alpha) and affects viral infection at an early, post-entry step.

Physicochemical characterization of the recombinant lectin scytovirin and microbicidal activity of the SD1 domain produced in rice against HIV-1.

Rice-produced SD1 retains its physicochemical properties and provides efficient pre-exposure HIV-1 prophylaxis against infection in vitro. Scytovirin (SVN) is an HIV-neutralizing lectin that features two structural domains (SD1 and SD2) that bind to HIV-1 envelope glycoproteins. We expressed SD1 in rice seeds as a potential large-scale production platform and confirmed that rice-derived SD1 binds the HIV-1 envelope glycoprotein gp120 in vitro.

HIV-1 -Infection Mediated by DCs: The Tip of the Iceberg of Cell-to-Cell Viral Transmission.

HIV-1 cell-to-cell transmission is key for an effective viral replication that evades immunity. This highly infectious mechanism is orchestrated by different cellular targets that utilize a wide variety of processes to efficiently transfer HIV-1 particles. Dendritic cells (DCs) are the most potent antigen presenting cells that initiate antiviral immune responses, but are also the cells with highest capacity to transfer HIV-1.

Mouthwashes with CPC Reduce the Infectivity of SARS-CoV-2 Variants In Vitro.

Oral mouthwashes decrease the infectivity of several respiratory viruses including SARS-CoV-2. However, the precise agents with antiviral activity in these oral rinses and their exact mechanism of action remain unknown. Here we show that cetylpyridinium chloride (CPC), a quaternary ammonium compound in many oral mouthwashes, reduces SARS-CoV-2 infectivity by inhibiting the viral fusion step with target cells after disrupting the integrity of the viral envelope.

Same-day SARS-CoV-2 antigen test screening in an indoor mass-gathering live music event: a randomised controlled trial.

Background: The banning of mass-gathering indoor events to prevent SARS-CoV-2 spread has had an important effect on local economies. Despite growing evidence on the suitability of antigen-detecting rapid diagnostic tests (Ag-RDT) for mass screening at the event entry, this strategy has not been assessed under controlled conditions. We aimed to assess the effectiveness of a prevention strategy during a live indoor concert.

Identification of Plitidepsin as Potent Inhibitor of SARS-CoV-2-Induced Cytopathic Effect After a Drug Repurposing Screen.

There is an urgent need to identify therapeutics for the treatment of Coronavirus disease 2019 (COVID-19). Although different antivirals are given for the clinical management of SARS-CoV-2 infection, their efficacy is still under evaluation. Here, we have screened existing drugs approved for human use in a variety of diseases, to compare how they counteract SARS-CoV-2-induced cytopathic effect and viral replication Among the potential 72 antivirals tested herein that were previously proposed to inhibit SARS-CoV-2 infection, only 18 % had an IC below 25 µM or 10 IU/ml.

SARS-CoV-2 Cellular Infection and Therapeutic Opportunities: Lessons Learned from Ebola Virus.

Viruses rely on the cellular machinery to replicate and propagate within newly infected individuals. Thus, viral entry into the host cell sets up the stage for productive infection and disease progression. Different viruses exploit distinct cellular receptors for viral entry; however, numerous viral internalization mechanisms are shared by very diverse viral families.