The coronavirus disease 2019 (COVID-19) pandemic is an exceptional public health crisis that demands the timely creation of new therapeutics and viral detection. Owing to their high specificity and ...reliability, monoclonal antibodies (mAbs) have emerged as powerful tools to treat and detect numerous diseases. Hence, many researchers have begun to urgently develop Ab-based kits for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Ab drugs for use as COVID-19 therapeutic agents. The detailed structure of the SARS-CoV-2 spike protein is known, and since this protein is key for viral infection, its receptor-binding domain (RBD) has become a major target for therapeutic Ab development. Because SARS-CoV-2 is an RNA virus with a high mutation rate, especially under the selective pressure of aggressively deployed prophylactic vaccines and neutralizing Abs, the use of Ab cocktails is expected to be an important strategy for effective COVID-19 treatment. Moreover, SARS-CoV-2 infection may stimulate an overactive immune response, resulting in a cytokine storm that drives severe disease progression. Abs to combat cytokine storms have also been under intense development as treatments for COVID-19. In addition to their use as drugs, Abs are currently being utilized in SARS-CoV-2 detection tests, including antigen and immunoglobulin tests. Such Ab-based detection tests are crucial surveillance tools that can be used to prevent the spread of COVID-19. Herein, we highlight some key points regarding mAb-based detection tests and treatments for the COVID-19 pandemic.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The novel coronavirus disease (COVID-19) pandemic remains a global public health crisis, presenting a broad range of challenges. To help address some of the main problems, the scientific community ...has designed vaccines, diagnostic tools and therapeutics for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The rapid pace of technology development, especially with regard to vaccines, represents a stunning and historic scientific achievement. Nevertheless, many challenges remain to be overcome, such as improving vaccine and drug treatment efficacies for emergent mutant strains of SARS-CoV-2. Outbreaks of more infectious variants continue to diminish the utility of available vaccines and drugs. Thus, the effectiveness of vaccines and drugs against the most current variants is a primary consideration in the continual analyses of clinical data that supports updated regulatory decisions. The first two vaccines granted Emergency Use Authorizations (EUAs), BNT162b2 and mRNA-1273, still show more than 60% protection efficacy against the most widespread current SARS-CoV-2 variant, Omicron. This variant carries more than 30 mutations in the spike protein, which has largely abrogated the neutralizing effects of therapeutic antibodies. Fortunately, some neutralizing antibodies and antiviral COVID-19 drugs treatments have shown continued clinical benefits. In this review, we provide a framework for understanding the ongoing development efforts for different types of vaccines and therapeutics, including small molecule and antibody drugs. The ripple effects of newly emergent variants, including updates to vaccines and drug repurposing efforts, are summarized. In addition, we summarize the clinical trials supporting the development and distribution of vaccines, small molecule drugs, and therapeutic antibodies with broad-spectrum activity against SARS-CoV-2 strains.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Mitigation strategies of the coronavirus disease 2019 (COVID-19) pandemic have been greatly hindered by the continuous emergence of SARS-CoV-2 variants. New sensitive, rapid diagnostic tests for the ...wide-spectrum detection of viral variants are needed. We generated a panel of 41 monoclonal antibodies against the SARS-CoV-2 nucleocapsid protein (NP) by using mice hybridoma techniques. Of these mAbs, nine exhibited high binding activities and were applied in latex-based lateral flow immunoassays (LFIAs). The LFIAs utilizing NP-mAb-7 and -40 had the best sensitivity and lowest limit of detection: 8 pg for purified NP and 625 TCID50/mL for the authentic virus (hCoV-19/Taiwan/4/2020). The specificity tests showed that the NP-mAb-40/7 LFIA strips did not cross-react with five human coronavirus strains or 20 other common respiratory pathogens. Importantly, we found that 10 NP mutants, including alpha (B.1.1.7), beta (B.1.351), gamma (P.1), and delta (B.1.617.2) variants, could be detected by NP-mAb-40/7 LFIA strips. A clinical study (n = 60) of the NP-mAb-40/7 LFIA strips demonstrated a specificity of 100% and sensitivity of 90% in infected individuals with cycle threshold (Ct) values < 29.5. These anti-NP mAbs have strong potential for use in the clinical detection of SARS-CoV-2 infection, whether the virus is wild-type or a variant of concern.
Nucleic acid-based therapeutics have demonstrated their efficacy in the treatment of various diseases and vaccine development. Antisense oligonucleotide (ASO) technology exploits a single-strand ...short oligonucleotide to either cause target RNA degradation or sterically block the binding of cellular factors or machineries to the target RNA. Chemical modification or bioconjugation of ASOs can enhance both its pharmacokinetic and pharmacodynamic performance, and it enables customization for a specific clinical purpose. ASO-based therapies have been used for treatment of genetic disorders, cancer and viral infections. In particular, ASOs can be rapidly developed for newly emerging virus and their reemerging variants. This review discusses ASO modifications and delivery options as well as the design of antiviral ASOs. A better understanding of the viral life cycle and virus-host interactions as well as advances in oligonucleotide technology will benefit the development of ASO-based antiviral therapies.
Out-of-hospital cardiac arrest (OHCA) affects over 360,000 adults in the United States each year with a 50-80% mortality prior to reaching medical care. Despite aggressive supportive care and ...targeted temperature management (TTM), half of adults do not live to hospital discharge and nearly one-third of survivors have significant neurologic injury. The current treatment approach following cardiac arrest resuscitation consists primarily of supportive care and possible TTM. While these current treatments are commonly used, mortality remains high, and survivors often develop lasting neurologic and cardiac sequela well after resuscitation. Hence, there is a critical need for further therapeutic development of adjunctive therapies. While select therapeutics have been experimentally investigated, one promising agent that has shown benefit is CO. While CO has traditionally been thought of as a cellular poison, there is both experimental and clinical evidence that demonstrate benefit and safety in ischemia with lower doses related to improved cardiac/neurologic outcomes. While CO is well known for its poisonous effects, CO is a generated physiologically in cells through the breakdown of heme oxygenase (HO) enzymes and has potent antioxidant and anti-inflammatory activities. While CO has been studied in myocardial infarction itself, the role of CO in cardiac arrest and post-arrest care as a therapeutic is less defined. Currently, the standard of care for post-arrest patients consists primarily of supportive care and TTM. Despite current standard of care, the neurological prognosis following cardiac arrest and return of spontaneous circulation (ROSC) remains poor with patients often left with severe disability due to brain injury primarily affecting the cortex and hippocampus. Thus, investigations of novel therapies to mitigate post-arrest injury are clearly warranted. The primary objective of this proposed study is to combine our expertise in swine models of CO and cardiac arrest for future investigations on the cellular protective effects of low dose CO. We will combine our innovative multi-modal diagnostic platform to assess cerebral metabolism and changes in mitochondrial function in swine that undergo cardiac arrest with therapeutic application of CO.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Patients with severe COVID‐19 often suffer from lymphopenia, which is linked to T‐cell sequestration, cytokine storm, and mortality. However, it remains largely unknown how severe acute respiratory ...syndrome coronavirus 2 (SARS‐CoV‐2) induces lymphopenia. Here, we studied the transcriptomic profile and epigenomic alterations involved in cytokine production by SARS‐CoV‐2‐infected cells. We adopted a reverse time‐order gene coexpression network approach to analyze time‐series RNA‐sequencing data, revealing epigenetic modifications at the late stage of viral egress. Furthermore, we identified SARS‐CoV‐2‐activated nuclear factor‐κB (NF‐κB) and interferon regulatory factor 1 (IRF1) pathways contributing to viral infection and COVID‐19 severity through epigenetic analysis of H3K4me3 chromatin immunoprecipitation sequencing. Cross‐referencing our transcriptomic and epigenomic data sets revealed that coupling NF‐κB and IRF1 pathways mediate programmed death ligand‐1 (PD‐L1) immunosuppressive programs. Interestingly, we observed higher PD‐L1 expression in Omicron‐infected cells than SARS‐CoV‐2 infected cells. Blocking PD‐L1 at an early stage of virally‐infected AAV‐hACE2 mice significantly recovered lymphocyte counts and lowered inflammatory cytokine levels. Our findings indicate that targeting the SARS‐CoV‐2‐mediated NF‐κB and IRF1‐PD‐L1 axis may represent an alternative strategy to reduce COVID‐19 severity.
This study investigates wave height transformation caused by either a single high-crest or a series of low-crest submerged rectangular breakwaters through laboratory experiments and numerical ...simulations. The series configuration induces Bragg reflection without wave breaking, while the single breakwater leads to wave breaking. Numerical models, employing two-dimensional RANS equations coupled with the k-ε turbulence model, are validated against experimental data. The analysis encompasses wave height transformations, wave reflection and transmission coefficients, and the flow field linked to different breakwater arrangements. Results indicate that the four-breakwater series prominently demonstrates Bragg reflection, resulting in reduced transmission wave height. Conversely, the single high-crest submerged breakwater induces wave breaking, dissipating more turbulence energy and yielding a similar transmission wave height. Additionally, the wave run-up height on the rear slope behind breakwaters is lower in the single breakwater scenario under identical incident wave conditions.
•Compares wave height at single high-crest vs. series of low-crest breakwaters.•Four breakwaters exhibit Bragg reflection, significantly reducing transmission height.•Single breakwater induces wave breaking, resulting in similar transmission height.•Under identical wave conditions, run-up on the rear slope is lower in single breakwater.•Practical configurations inducing wave breaking may enhance coastal protection.
Abstract
Background
Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), an RNA virus with a high mutation rate. Importantly, several ...currently circulating SARS-CoV-2 variants are associated with loss of efficacy for both vaccines and neutralizing antibodies.
Methods
We analyzed the binding activity of six highly potent antibodies to the spike proteins of SARS-CoV-2 variants, assessed their neutralizing abilities with pseudovirus and authentic SARS-CoV-2 variants and evaluate efficacy of antibody cocktail in Delta SARS-CoV-2-infected hamster models as prophylactic and post-infection treatments.
Results
The tested RBD-chAbs, except RBD-chAb-25, maintained binding ability to spike proteins from SARS-CoV-2 variants. However, only RBD-chAb-45 and -51 retained neutralizing activities; RBD-chAb-1, -15, -25 and -28 exhibited diminished neutralization for all SARS-CoV-2 variants. Notably, several cocktails of our antibodies showed low IC
50
values (3.35–27.06 ng/ml) against the SARS-CoV-2 variant pseudoviruses including United Kingdom variant B.1.1.7 (Alpha), South Africa variant B.1.351 (Beta), Brazil variant P1 (Gamma), California variant B.1.429 (Epsilon), New York variant B.1.526 (Iota), and India variants, B.1.617.1 (Kappa) and B.1.617.2 (Delta). RBD-chAb-45, and -51 showed PRNT
50
values 4.93–37.54 ng/ml when used as single treatments or in combination with RBD-chAb-15 or -28, according to plaque assays with authentic Alpha, Gamma and Delta SARS-CoV-2 variants. Furthermore, the antibody cocktail of RBD-chAb-15 and -45 exhibited potent prophylactic and therapeutic effects in Delta SARS-CoV-2 variant-infected hamsters.
Conclusions
The cocktail of RBD-chAbs exhibited potent neutralizing activities against SARS-CoV-2 variants. These antibody cocktails are highly promising candidate tools for controlling new SARS-CoV-2 variants, including Delta.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Background Stevens-Johnson syndrome (SJS) and its related disease, toxic epidermal necrolysis (TEN), are life-threatening drug hypersensitivities with robust immune responses to drugs. Despite the ...strong HLA predisposition to drug hypersensitivities, such as HLA-B∗1502 to carbamazepine (CBZ)–induced SJS/TEN, it remains unknown whether particular T-cell receptors (TCRs) participate in recognition of small drug/peptide–HLA complexes. Objective Using the strong HLA predisposition in patients with CBZ-induced SJS/TEN as a model, we aimed to study the use of TCR repertoire in patients with drug hypersensitivity. Method We enrolled patients with CBZ-SJS/TEN, tolerant control subjects, and healthy subjects who had no history of CBZ exposure. We isolated PBMCs from the subjects, cultured CBZ-specific T cells, and globally investigated the expression level and third complementarity-determining region length distribution of the TCR profile. We further assessed the pathogenic role of the disease-specific clonotype using real-time PCR–based tests and functional analysis. Results On drug stimulation, CBZ-specific CD8+ T cells were expanded in vitro and activated to release granulysin. Notably, VB-11-ISGSY was identified as the most predominant clonotype and shared among different subjects. This clonotype was present in 16 (84%) of 19 patients with SJS/TEN, absent in all 17 tolerant patients, and present at a low frequency in healthy subjects (4/29 14%). CBZ-specific cytotoxicity could be primed in vitro in the PBMCs of healthy subjects who are carriers of HLA-B∗1502 and VB-11-ISGSY; this cytotoxicity could be blocked by an anti–TCR-VB-11 antibody. Furthermore, a single T-cell clone expressing VA-22-FISGTY/VB-11-ISGSY showed significant cytotoxicity against HLA-B∗1502–positive antigen-presenting cells and CBZ. Conclusion This study establishes the key role of the TCR in the pathogenic mechanism of SJS/TEN, explains why some HLA-B∗1502 carriers are tolerant to CBZ, and provides a biomarker profile for drug hypersensitivity.
PDF
