Analysis of Beyfortus® (Nirsevimab) Immunization Campaign: Effectiveness, Biases, and ADE Risks in RSV Prevention.

Respiratory infections with respiratory syncytial virus (RSV) account for an important part of hospital admissions for acute respiratory infections. Nirsevimab has been developed to reduce the hospital burden of RSV infections. Compared with the product previously used, it has a stronger binding capacity to RSV F protein and a high affinity for FcRn (neonatal receptor for the Fc fragment of IgG), which extends its lifespan. Nirsevimab has been shown to be highly effective in reducing hospitalization rates of RSV infections but a large or unknown number of treated subjects have been excluded in clinical and post-marketing studies. However, analysis of these studies cannot exclude that, in rare cases, nirsevimab facilitates and worsens RSV infection (or other respiratory infections). This could be attributable to antibody-dependent enhancement (ADE) which has been observed with RSV F protein antibodies in inactivated vaccine trials. This risk has been incompletely assessed in pre-clinical and clinical trials (incomplete exploration of nirsevimab effector functions and pharmacokinetics). ADE by disruption of the immune system (not studied and due to FcRn binding) could explain why there is no reduction in all-cause hospital admissions in treated age groups. Given the high price of nirsevimab, the cost-effectiveness of mass immunization campaigns may therefore be debated from an economic as well as a scientific point of view.

Vaccination strategies for patients under monoclonal antibody and other biological treatments: an updated comprehensive review based on EMA authorisations to January 2024.

INTRODUCTION: Monoclonal antibodies (mAbs) and other biological agents are being increasingly approved in the last years with very different indications. Their highly heterogeneous immunosuppressive effects, mechanisms of action and pharmacokinetics require comprehensive individualized vaccination schedules. AREAS COVERED: Vaccination for immunocompromised patients. Prevention and treatment with mAbs and other biological therapies. EXPERT OPINION: Current recommendations on vaccine schedules for patients under mAbs or other biological treatments are based on expert opinions and are not individualized according to each vaccine and treatment. No studies are focusing on the high heterogeneity of these agents, which are exponentially developed and used for many different indications. Recent paradigm changes in vaccine development (boosted by the COVID-19 pandemic) and in the mAbs use for prophylactic purposes (changing 'vaccination' by 'immunization' schedules) has been witnessed in the last years. We aimed at collecting all mAbs used for treatment or prevention, approved as of 1 January 2024, by the EMA. Based on available data on mAbs and vaccines, we propose a comprehensive guide for personalizing vaccination. Recent vaccine developments and current population strategies (e.g. zoster vaccination or prophylactic nirsevimab) are discussed. This review aims to be a practical guideline for professionals working in vaccine consultations for immunosuppressed patients.

Immunotherapy for Parkinson's Disease and Alzheimer's Disease: A Promising Disease-Modifying Therapy.

Alzheimer's disease (AD) and Parkinson's disease (PD) are two neurodegenerative diseases posing a significant disease burden due to their increasing prevalence and socio-economic cost. Traditional therapeutic approaches for these diseases exist but provide limited symptomatic relief without addressing the underlying pathologies. This review examines the potential of immunotherapy, specifically monoclonal antibodies (mAbs), as disease-modifying treatments for AD and PD. We analyze the pathological mechanisms of AD and PD, focusing on the roles of amyloid-beta (Aß), tau (τ), and alpha-synuclein (α-syn) proteins. We discuss the latest advancements in mAb therapies targeting these proteins, evaluating their efficacy in clinical trials and preclinical studies. We also explore the challenges faced in translating these therapies from bench to bedside, including issues related to safety, specificity, and clinical trial design. Additionally, we highlight future directions for research, emphasizing the need for combination therapies, improved biomarkers, and personalized treatment strategies. This review aims to provide insights into the current state and future potential of antibody-based immunotherapy in modifying the course of AD and PD, ultimately improving patient outcomes and quality of life.

Calcitonin Gene-Related Peptide Monoclonal Antibodies: Key Lessons from Real-World Evidence.

BACKGROUND: The advent of monoclonal antibodies (mAbs) targeting the calcitonin gene-related peptide (CGRP) pathway has transformed the management of migraine, offering newfound optimism for clinicians and individuals with episodic migraine (EM) and chronic migraine (CM). While randomized controlled trials (RCTs) have provided crucial insights into the effectiveness and safety profiles of these treatments, their translation into real-world clinical practice remains a challenge. OBJECTIVE: This review aims to conduct a comprehensive assessment of real-world studies, offering valuable insights tailored for practical application in clinical settings. METHODS: We conducted a comprehensive literature search in PubMed, SCOPUS, and MEDLINE for real-life studies on erenumab, fremanezumab, and galcanezumab. Abstracts underwent rigorous screening by two reviewers for relevance. Data extraction from selected articles was performed using a standardized form, with verification by a second reviewer. Data synthesis was narrative, following PRISMA guidelines. RESULTS: Our search included 61 pertinent studies conducted between 2019 and 1 March 2024. Real-world study designs demonstrated notable variability in the selection and inclusion of migraine patients, influenced by factors such as attack frequency, data collection criteria, and primary/secondary objectives. Key findings commonly reported considerable improvements in efficacy outcomes (migraine frequency, analgesic use, pain severity, and disability), high responder rates, and optimal safety and tolerability profiles. CONCLUSIONS: Real-world evidence underscores the role of anti-CGRP mAbs as targeted therapies for both CM and EM patients. The overall results indicate that the effectiveness and tolerability of anti-CGRP mAbs in real-world applications may exceed those observed in RCTs, an extraordinary finding in clinical neurology.

Immunofluorescent detection of protein CoAlation in mammalian cells under oxidative stress.

Previously, we reported the generation and characterisation of highly specific anti-CoA monoclonal antibodies capable of recognizing CoA in various immunological assays. Utilizing these antibodies in conjunction with mass spectrometry, we identified a wide array of cellular proteins modified by CoA in bacteria and mammalian cells. Furthermore, our findings demonstrated that such modifications could be induced by oxidative or metabolic stress. This study advances the utility of anti-CoA monoclonal antibodies in analysing protein CoAlation, highlighting their effectiveness in immunofluorescent assay. Our data corroborates a significant increase in cellular protein CoAlation induced by oxidative agents. Additionally, we observed that hydrogen-peroxide induced protein CoAlation is predominantly associated with mitochondrial proteins.

Filling the data gap on CGRP mAb therapy in low- to middle-income countries in Southeast Asia: insights from a real-world study in Thailand.

BACKGROUND: Most real-world data on CGRP mAbs have been published from high-income countries such as the USA, Western countries, Japan, Korea, and Singapore. However, data from low- and middle-income countries in Southeast Asia is lacking. This is the first real-world study from Thailand to describe the efficacy of CGRP mAbs therapy in migraine patients and to analyze the response trends between episodic migraine and chronic migraine. METHODS: We conducted a single-center, real-world retrospective chart review study with an observation period of 6 months after CGRP mAbs initiation. We aim to compare treatment responses to CGRP mAbs between EM and CM patients. RESULTS: A total of 47 Thai patients were enrolled (median [IQR] age 37.2 [28.6-50.4] years; 85.1%F, 44.7% EM; 70.2% galcanezumab). There was no difference in baseline characteristics and migraine disability assessment (MIDAS) between EM and CM. The overall ≥ 30%, ≥ 50%, and ≥ 70% monthly migraine day reduction rates at 6 months were 89.0%, 71.6%, and 58.5% with higher responders in EM. There was a significant decrease in monthly headache days (MHDs) over time (adjusted ß = -0.42, p < 0.001) and a significant decrease in MIDAS score over time after the initiation of CGRP mAbs (adjusted ß = -1.12, p = 0.003). However, there were no differences between the two diagnoses. There was no significant decrease in the number of abortive medication pills used over time after the initiation of CGRP mAbs. CM had a significantly steeper trend compared to those with EM. CONCLUSION: The first real-world study in Thailand demonstrated that CGRP mAbs therapy had efficacy for migraine treatment, as evidenced by a reduction in MHDs, decreased disability, and reduced use of abortive medications. Additionally, the response pattern to CGRP mAbs therapy was similar between EM and CM in terms of MHDs reduction and MIDAS score improvement.

Unlocking Trehalose's versatility: A comprehensive Journey from biosynthesis to therapeutic applications.

For over forty years, a sugar of rare configuration known as trehalose (two molecules of glucose linked at their 1-carbons), has been recognised for more than just its roles as a storage compound. The ability of trehalose to protect an extensive range of biological materials, for instance cell lines, tissues, proteins and DNA, has sparked considerable interest in the biotechnology and pharmaceutical industries. Currently, trehalose is now being investigated as a promising therapeutic candidate for human use, as it has shown potential to reduce disease severity in various experimental models. Despite its diverse biological effects, the precise mechanism underlying this observation remain unclear. Therefore, this review delves into the significance of trehalose biosynthesis pathway in the development of novel drug, investigates the inhibitors of trehalose synthesis and evaluates the binding efficiency of T6P with TPS1. Additionally, it also emphasizes the knowledge about the protective effect of trehalose on modulation of autophagy, combating viral infections, addressing the conditions like cancer and neurodegenerative diseases based on the recent advancement. Furthermore, review also highlight the trehalose's emerging role as a surfactant in delivering monoclonal antibodies that will further broadening its potential application in biomedicines.

Evaluation of Anti-CAR Linker mAbs for CAR T Monitoring after BiTEs/bsAbs and CAR T-Cell Pretreatment.

For the monitoring of chimeric antigen receptor (CAR) T-cell therapies, antigen-based CAR detection methods are usually applied. However, for each target-antigen, a separate detection system is required. Furthermore, when monitored CAR T-cells in the blood of patients treated with bispecific antibodies or T-cell engagers (bsAbs/BiTEs) recognize the same antigen, these methods produce false-positive results in clinical diagnostics. Anti-CAR-linker monoclonal antibodies (mAbs) targeting the linker sequence between the variable domains of the antigen binding CAR fragment promise a universal and unbiased CAR detection. To test this, we analyzed clinical specimens of all BCMA- and CD19-targeting CAR T-cell products currently approved for clinical use. We found a highly specific and sensitive CAR detection using anti-CAR-linker mAb in blood cells from patients treated with Ide-cel, Tisa-cel, Axi-cel, Brexu-cel, and Liso-cel. For Ide-cel and Tisa-cel, the sensitivity was significantly lower compared to that for antigen-based CAR detection assays. Strikingly, the specificity of anti-CAR linker mAb was not affected by the simultaneous presence of bispecific blinatumomab or teclistamab for Axi-cel, Brexu-cel, Liso-cel, or Ide-cel, respectively. Cilta-cel (containing a monomeric G4S-CAR linker) could not be detected by anti-CAR linker mAb. In conclusion, anti-CAR-linker mAbs are highly specific and useful for CAR T-cell monitoring but are not universally applicable.

Identification and characterization of linear epitopes of monoclonal antibodies against the capsid proteins of small ruminant lentiviruses.

Maedi-visna virus (MVV) and caprine arthritis encephalitis virus (CAEV) are members of a group of genetically highly homologous lentiviruses collectively referred to as small ruminant lentiviruses (SRLVs). SRLVs can infect sheep, goats and other small ruminants, causing multisystemic disease with progressive and persistent inflammatory changes, severely reducing animal productivity and impeding animal trade. The capsid protein of SRLVs, p28, is highly conserved among strains and is a commonly used marker for the detection of SRLVs. In this study, two monoclonal antibodies (mAbs), designated G8F7 and A10C12, against p28 were generated using a recombinant p28 protein expressed in Escherichia coli as an immunogen. Functional analysis showed that these two monoclonal antibodies could be used in iELISA, immunofluorescence assays (IFA) and western blot assays to detect p28 or Gag precursor proteins of SRLVs. Two linear epitopes, 61GNRAQKELIQGKLNEEA77 (E61-77) and 187CQKQMDRVLGTRVQQATVEEKMQACR212 (E187-212), which are recognized by G8F7 and A10C12, respectively, were identified through truncation of the GST-fused p28. Amino acid sequence alignment showed that the epitope E61-77 is conserved among SRLVs, with a dominant mutation site (K72R) that does not disrupt recognition by G8F7. E187-212 was found to exhibit variability among SRLVs, but the majority of mutant epitopes are recognized by A10C12, with the exception of a mutant epitope from an isolate with undefined subtypes from Ovis aries, which was not recognized. These findings may facilitate future study of SRLVs and promote the development of methods for the detection of these viruses.

Development and characterization of monoclonal antibodies recognizing nucleocapsid protein of multiple SARS-CoV-2 variants.

Rapid antigen test (RAT) is widely used for SARS-CoV-2 infection diagnostics. However, test sensitivity has decreased recently due to the emergence of the Omicron variant and its sublineages. Here we developed a panel of SARS-CoV-2 nucleocapsid protein (NP) specific mouse monoclonal antibodies (mAbs) and assessed their sensitivity and specificity to important SARS-CoV-2 variants. We identified seven mAbs that exhibited strong reactivity to SARS-CoV-2 variants and recombinant NP (rNP) by Western immunoblot or ELISA. Their specificity to SARS-CoV-2 was confirmed by negative or low reactivity to rNPs from SARS-CoV-1, MERS, and common human coronaviruses (HCoV-HKU1, HCoV-CO43, HCoV-NL63, and HCoV-229E). These seven mAbs were further tested by immunoplaque assay against selected variants of concern (VOCs), including two Omicron sublineages, and five mAbs (F461G13, F461G7, F459G7, F457G3, and F461G6), showed strong reactions, warranting further suitability testing for the development of diagnostic assay.

A Medical Claims Database Study of Factors Associated with Medication Adherence and Treatment Persistence in Patients Receiving PCSK9 Monoclonal Antibodies.

AIM: To investigate medication adherence and treatment persistence in patients receiving proprotein convertase subtilisin/kexin type 9 (PCSK9) monoclonal antibodies (mAbs) in Japan. METHODS: Using an anonymized claims database from January 2015 to December 2021, data on adult patients at high risk for atherosclerotic cardiovascular disease or with a history of coronary artery disease (CAD) who had at least 1 prescription for PCSK9-mAbs were retrieved. RESULTS: In total, 276 patients were analyzed. The cumulative treatment persistence rate after 1 year was 67.0%. A multivariate analysis revealed that better adherence to oral low-density lipoprotein cholesterol (LDL-C)-lowering therapy in the year before starting PCSK9-mAbs (adjusted odds ratio [OR] 2.16) and a history of CAD for secondary prevention (adjusted OR 2.44) were associated with better adherence to PCSK9-mAbs in the first year. Better adherence to oral LDL-C-lowering therapy in the year before starting PCSK9-mAbs (adjusted OR 2.32) and a history of CAD for secondary prevention (adjusted OR 3.03) were also associated with a lower rate of discontinuation of PCSK9-mAbs. Age, sex, comorbidity, number of tablets taken daily (all medications), and number of hospital or clinic visits in the year prior to starting PCSK9-mAbs did not affect the persistence rate or adherence to PCSK9-mAbs in the multivariate analyses. CONCLUSION: Better adherence to oral LDL-C-lowering therapy and secondary prevention were identified as factors associated with better medication adherence and treatment persistence in patients receiving PCSK9-mAbs within the first year.

Advances in Systemic Lupus Erythematosus Treatment With Monoclonal Antibodies: A Mini-Review.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that affects multiple organs and systems. It is characterized by the production of abnormal antibodies that attack healthy cells and tissues. The disease presents a wide range of symptoms and severity, from mild to severe. Diagnosis can be complex, but the classification criteria of the American College of Rheumatology (ACR) help to facilitate it. Incidence and prevalence vary considerably worldwide, mainly affecting adult women between the third and fourth decades of life, although it can also occur in childhood. The prognosis of SLE has improved over time, but there is still a risk of irreversible organ damage. Treatment is individualized for each patient and is based on immunosuppression and the use of corticosteroids. Biological therapies, such as monoclonal antibodies, have emerged as a more specific alternative. Methotrexate, antimalarials, glucocorticoids, immunosuppressants, and monoclonal antibodies are some of the medications used to treat SLE. New therapeutic strategies are currently being developed, such as targeted therapies, immunomodulators, and biological agents. Treatment adherence, monitoring, and regular follow-up are important aspects of SLE management. This article aims to describe the characteristics of the new monoclonal antibody therapies that exist for the management of SLE.

NK Cell Degranulation Triggered by Rituximab Identifies Potential Markers of Subpopulations with Enhanced Cytotoxicity toward Malignant B Cells.

A promising strategy in cancer immunotherapy is to restore or enhance the cytotoxicity of NK cells, among others, by activating the mechanism of antibody-dependent cellular cytotoxicity (ADCC). Monoclonal antibodies targeting tumor antigens, such as rituximab (targeting CD20), induce NK cell-mediated ADCC and have been used to treat B cell malignancies, such as non-Hodgkin lymphoma, but not always successfully. The aim of this study was to analyze the gene expression profile of the NK cells involved in the cytolytic response stimulated by rituximab. NK cells were co-cultured with rituximab-opsonized Raji cells. Sorting into responder and non-responder groups was based on the presence of CD107a, which is a degranulation marker. RNA-seq results showed that the KIT and TNFSF4 genes were strongly down-regulated in the degranulating population of NK cells (responders); this was further confirmed by qRT-PCR. Both genes encode surface proteins with cellular signaling abilities, namely c-KIT and the OX40 ligand. Consistent with our findings, c-KIT was previously reported to correlate inversely with cytokine production by activated NK cells. The significance of these findings for cancer immunotherapy seems essential, as the pharmacological inhibition of c-KIT and OX40L, or gene ablation, could be further tested for the enhancement of the anti-tumor activity of NK cells in response to rituximab.

Impact of ligand structure and base bead pore size on host cell protein removal during monoclonal antibody purification using multimodal chromatography resin.

Despite advancements in therapeutic monoclonal antibodies (mAbs) and cell line engineering, separating host cell proteins (HCPs) from mAbs during downstream purification remains challenging. Therefore, in this study, we developed a novel multimodal chromatography (MMC) resin to enhance HCP removal during mAb polishing processes. We evaluated the impact of both ligand structure and pore size of the MMC resin by purifying a post-protein A chromatography solution in flow-through mode. We observed that the efficiency of HCP clearance depended on the hydrophobic moiety structure of the ligand and predicted the mAb purification capability of MMC through linear salt-gradient elution experiments involving a mixture of transferrin, bovine serum albumin (BSA), and pepsin. Our findings revealed that the prototype immobilized 1,12-dodecanediamine via the formyl group exhibited the best performance attributed to its long alkyl chain. Furthermore, an investigation of effects of base bead pore size on HCP capacity using cellulose base beads of five different pore sizes showed that larger pore resin base beads had the highest HCP removal capacity. Specifically, MMC resins with a pore diameter exceeding 440 nm reduced the HCP level by three orders of magnitude under high mAb loading conditions (> 1000 mg/mL-resin). The MMC resin developed in this study, along with the insights gained into ligand structure and pore size, not only enhances mAb polishing efficiency but also contributes to improving downstream processes in mAb biopharmaceutical production.

Receptor tyrosine kinase-like orphan receptor serves as a potential target in cancer immunotherapy.

Receptor tyrosine kinase-like orphan receptor (ROR), consisting of ROR1 and ROR2, is a conserved family of receptor tyrosine kinase superfamily that plays crucial roles during embryonic development with limited expression in adult normal tissues. However, it is overexpressed in a range of hematological malignancies and solid tumors and functions in cellular processes including cell survival, polarity, and migration, serving as a potential target in cancer immunotherapy. This review summarizes the expression and structure of ROR in developmental morphogenesis and its function in cancers associated with Wnt5a signaling and highlights the cancer immunotherapy strategies targeting ROR.

Evaluating the Effectiveness, Tolerability, and Safety of Eptinezumab in High-Frequency and Chronic Migraine in Real World: EMBRACE-The First Italian Multicenter, Prospective, Real-Life Study.

We conducted a multicenter, prospective study (EMBRACE) evaluating the real-life effectiveness, safety, and tolerability of eptinezumab (100 mg/300 mg)-a monoclonal antibody targeting the calcitonin-gene-related peptide (anti-CGRP mAb)-in high-frequency episodic migraine (HFEM) or chronic migraine (CM). The primary endpoint was the change in monthly migraine days (MMD) for HFEM or monthly headache days (MHD) for CM at weeks 9-12 compared to baseline. The secondary endpoints included changes in monthly analgesic intake (MAI), Numerical Rating Scale (NRS), Headache Impact Test (HIT-6), Migraine Disability Assessment Scale (MIDAS), Migraine Interictal Burden Scale (MIBS-4), and responder rates. The safety analysis involved 44 subjects; the effectiveness analysis included 26 individuals. Eptinezumab was well-tolerated. In CM patients, eptinezumab significantly reduced MHD (-16.1 ± 9.9, p < 0.001), MAI, NRS, HIT-6, MIDAS, and MIBS-4. In HFEM patients, it significantly reduced NRS, HIT-6, MIDAS, and MIBS-4, though reductions in MMD (-3.3 ± 4.5) and MAI were not statistically significant. Overall, ≥50% and ≥75% response rates were 61.5% and 30.8%, respectively (60% and 30% in non-responders to subcutaneous anti-CGRP mAbs). The clinical change was rated as much or very much improved by 61.0% of the patients. Eptinezumab demonstrated high effectiveness, safety, and tolerability in real-life among hard-to-treat migraine patients with multiple treatment failures, including anti-CGRP mAbs.

Dissecting human monoclonal antibody responses from mRNA- and protein-based XBB.1.5 COVID-19 monovalent vaccines.

The emergence of highly contagious and immune-evasive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has required reformulation of coronavirus disease 2019 (COVID-19) vaccines to target those new variants specifically. While previous infections and booster vaccinations can enhance variant neutralization, it is unclear whether the monovalent version, administered using either mRNA or protein-based vaccine platforms, can elicit de novo B-cell responses specific for Omicron XBB.1.5 variants. Here, we dissected the genetic antibody repertoire of 603 individual plasmablasts derived from five individuals who received a monovalent XBB.1.5 vaccination either with mRNA (Moderna or Pfizer/BioNtech) or adjuvanted protein (Novavax). From these sequences, we expressed 100 human monoclonal antibodies and determined binding, affinity and protective potential against several SARS-CoV-2 variants, including JN.1. We then select two vaccine-induced XBB.1.5 mAbs, M2 and M39. M2 mAb was a de novo, antibody, i.e., specific for XBB.1.5 but not ancestral SARS-CoV-2. M39 bound and neutralized both XBB.1.5 and JN.1 strains. Our high-resolution cryo-electron microscopy (EM) structures of M2 and M39 in complex with the XBB.1.5 spike glycoprotein defined the epitopes engaged and revealed the molecular determinants for the mAbs' specificity. These data show, at the molecular level, that monovalent, variant-specific vaccines can elicit functional antibodies, and shed light on potential functional and genetic differences of mAbs induced by vaccinations with different vaccine platforms.\.

The efficacy of antivirals, corticosteroids, and monoclonal antibodies as acute COVID-19 treatments in reducing the incidence of long COVID: a systematic review and meta-analysis.

BACKGROUND: Whether treatment during acute COVID-19 results in protective efficacy against long COVID incidence remains unclear. OBJECTIVES: To assess the relationship between acute COVID-19 treatments of antivirals, corticosteroids, and monoclonal antibodies (mAbs) and long COVID incidence, and their effects in different populations and individual symptoms. METHODS: A systematic review and meta-analysis. DATA SOURCES: Searches were conducted up to January 29, 2024 in PubMed, Medline, Web of Science, and Embase. STUDY ELIGIBILITY CRITERIA: Articles that reported long COVID incidence post-acute COVID with a follow-up of at least 30 days with no language restrictions. PARTICIPANTS: Patients with a COVID-19 diagnosis history. INTERVENTIONS: Patients treated with antivirals, corticosteroids or mAbs. ASSESSMENT OF RISK OF BIAS: Quality assessment was based on the Newcastle-Ottawa scale, risk of bias in nonrandomized studies of interventions-I and Cochrane risk of bias tool. METHODS OF DATA SYNTHESIS: Basic characteristics were documented for each study. Random forest model and meta-regression were used to evaluate the correlation between treatments and long COVID. RESULTS: Our search identified 2363 records, 32 of which were included in the qualitative synthesis and 25 included into the meta-analysis. Effect size from 14 papers investigating acute COVID-19 antiviral treatment concluded its protective efficacy against long COVID (OR, 0.61; 95% CI, 0.48-0.79; p 0.0002); however, corticosteroid (OR, 1.57; 95% CI, 0.80-3.09; p 0.1913), and mAbs treatments (OR, 0.94; 95% CI, 0.56-1.56; p 0.8012) did not generate such effect. Subsequent subgroup analysis revealed that antivirals provided stronger protection in the aged, male, unvaccinated and nondiabetic populations. Furthermore, antivirals effectively reduced 8 out of the 22 analysed long COVID symptoms. CONCLUSIONS: Our meta-analysis determined that antivirals reduced long COVID incidence across populations and should thus be recommended for acute COVID-19 treatment. There was no relationship between mAbs treatment and long COVID, but studies should be conducted to clarify acute COVID-19 corticosteroids' potential harmful effects on the post-acute phase of COVID-19.

Identification of a linear B-cell epitope on the "puff" loop of the Senecavirus A VP2 protein involved in receptor binding.

Senecavirus A (SVA) is an important emerging swine pathogen that causes vesicular lesions in swine and acute death in newborn piglets. VP2 plays a significant role in the production of antibodies, which can be used in development of diagnostic tools and vaccines. Herein, the aim of the current study was to identify B-cell epitopes (BCEs) of SVA for generation of epitope-based SVA marker vaccine. Three monoclonal antibodies (mAbs), named 2E4, 1B8, and 2C7, against the SVA VP2 protein were obtained, and two novel linear BCEs, 177SLGTYYR183 and 266SPYFNGL272, were identified by peptide scanning. The epitope 177SLGTYYR183 was recognized by the mAb 1B8 and was fully exposed on the VP2 surface, and alanine scanning analysis revealed that it contained a high continuity of key amino acids. Importantly, we confirmed that 177SLGTYYR183 locates on "the puff" region within the VP2 EF loop, and contains three key amino acid residues involved in receptor binding. Moreover, a single mutation, Y182A, blocked the interaction of the mutant virus with the mAb 1B8, indicating that this mutation is the pivotal point for antibody recognition. In summary, the BCEs that identified in this study could be used to develop diagnostic tools and an epitope-based SVA marker vaccine.