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La infección por el virus SARS-CoV-2, conocida como COVID-19, ha causado alta morbilidad y mortalidad en el mundo. Después de haber descifrado el código genético del virus y haber desarrollado un gran trabajo investigativo en la creación de vacunas, con diversas estrategias de acción, se ha logrado disminuir la morbi mortalidad. Fue necesario acelerar el proceso de producción de vacunas, lo cual estuvo facilitado por el avanzado conocimiento científico en el campo de la genética y la virología, para brindar a la especie humana una protección eficaz y segura contra la agresiva y progresiva infección. Las vacunas se clasifican de acuerdo con su mecanismo de acción, existen vacunas basadas en vectores virales que no se replican, vacunas recombinantes, otras basadas en virus atenuados y virus inactivos, y (la gran novedad de la ciencia actual) las vacunas basadas en ARN mensajero y ADN. Estas últimas han demostrado una gran eficacia y seguridad en la prevención de la infección por el SARS-CoV-2, también han impactado de manera fuerte, por lo que han reducido la infección y la mortalidad en la población. En consecuencia, cada día que pasa desde que se inició el periodo de vacunación mundial, se evidencia una reducción en la curva de contagio y mortalidad por COVID-19.
The infection produced by the SARS-CoV-2 virus, known as COVID-19, has caused high morbidity and mortality across the world. After having deciphered the virus's genoma and carried out investigative endeavors that led to the creation of a variety of vaccines with different mechanisms of action, it has been possible to decrease the morbidity and mortality associated with the virus. It was necessary to accelerate the vaccine production process, which was facilitated by advanced scientific knowledge within the disciplines of genetics and virology, in order to provide the human species with a safe and effective form of protection against the aggressive and progressive infection. Vaccines are classified differently depending on their action mechanisms: there are some based on non-replicating viral vectors, recombinant vaccines, ones that are based on attenuated or inactivated viruses, and (the greatest novelty of current scientific developments) vaccines based on DNA and messenger RNA. The latter has demonstrated significant efficacy and safety in the prevention of the SARS-CoV-2 infection as observed in preliminary studies, and they have meaningfully impacted the population by reducing the rates of infection and mortality. As a result, decreased levels of spread of and mortality from COVID-19 have been evidenced across the globe following the beginning of the vaccine distribution period.
A infecção pelo vírus SARS-CoV-2, conhecido como COVID-19, tem causado elevada morbidade e mortalidade no mundo. Depois de ter decifrado o código genético do virus e de ter realizado um grande trabalho de investigação na criação de vacinas, com diversas estratégias de ação, a morbilidade e a mortalidade foram reduzidas. Foi necessário acelerar o processo de produção de vacinas, facilitado por conhecimentos científicos avançados no domínio da genética e da virologia, para proporcionar à espécie humana uma proteção eficaz e segura contra a infecção agressiva e progressiva. As vacinas são classificadas de acordo com seu mecanismo de ação, existem vacinas baseadas em vetores virais que não se replicam, vacinas recombinantes, outras baseadas em virus atenuados e vírus inativos, e (a grande novidade da ciência atual) vacinas baseadas em RNA mensageiro e ADN. Estas últimas demonstraram grande eficácia e segurança na prevenção da infecção por SARS-CoV-2, mas também tiveram um forte impacto, razão pela qual reduziram a infecção e a mortalidade na população. Consequentemente, a cada dia que passa desde o início do período global de vacinação, fica evidente uma redução na curva de contágio e mortalidade por COVID-19.
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HumanosRESUMO
Objective To summarize and analyze the difficulties and key points in the measurement of gross α and gross β radioactivity in water based on the results of national measurement capability comparison assessment, and provide the basis and reference for the future work and the development of new local standards. Methods The research team participated in the comparison assessment for measurement of the gross radioactivity in water samples organized by National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention. According to the comparison assessment results and the content in the national standard GB/T 5750.13—2023 (published draft), the steps of spike recovery involved during the measurement were analyzed and discussed. Two different formulas used for spike recovery calculation were analyzed for their impact on the final measurement results. Results When the spike recovery F(derived) derived from the formulas was used for result calculation, the spike recovery ranged as follows: gross α: 63.00%−84.60%, and gross β: 95.0%−99.1%; 3/6 of the comparison results were determined as excellent and 3/6 as pass as a whole (among them, 4 were excellent and 2 were pass for both single gross α assessment items and single gross β assessment items). When the spike recovery F from the GB/T 5750.13—2023 (published draft) was used for result calculation, the spike recovery ranged as follows: gross α: 39.69%−71.57%, and gross β: 90.25%−98.21%; 5/6 of the comparison results were determined as fail and 1/6 as pass (among them, 5 were fail and 1 was pass for single gross α assessment items; 5 were excellent and 1 was pass for single gross β assessment items). When two different formulas were used for spike recovery calculation, there was a significant difference in gross α radioactivity measurement (t = 4.27, P = 0.03 < 0.05), but there was no significant difference in gross β radioactivity measurement (t = 0.667, P = 0.524 > 0.05). Conclusion In the measurement of gross α and gross β radioactivity in water, appropriate reference to the spike recovery has a great influence on the measurement results. Therefore, quality control should be strengthened to further ensure the accuracy of measurement.
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The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a serious impact on global public health and the economy. SARS-CoV-2 infiltrates host cells via its surface spike protein, which binds to angiotensin-converting enzyme 2 on the host cell membrane. As a result, small molecules targeting spike protein have emerged as a hotspot in anti-SARS-CoV-2 drug research. Activity screening is an important step in seeking small molecule drugs. Therefore, this article aims to review the biological activity evaluation methods of small molecule inhibitors targeting SARS-CoV-2 spike protein, with the goal of laying the foundation for the discovery of new anti-SARS-CoV-2 drugs.
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Resumen Este artículo no tiene como objetivo el presentar una descripción detallada de cada una de las encefalopatías epilépticas y del desarrollo, sino más bien discutir cam bios recientes en la terminología y criterios diagnósticos de ciertas encefalopatías, en base a una revisión actua lizada de los últimos 10 años. Se analizan cambios importantes en definiciones de síndromes específicos y nuevos tratamientos que han demostrado eficacia en el manejo de crisis convulsivas en estos pacientes. En conclusión: Las nuevas terapias de modulación genética, contribuirán no solo a reducir la carga de crisis epilépticas, sino también a mejorar el pronóstico cognitivo, y por lo tanto la calidad de vida.
Abstract It is not the intend of this article to present a de tailed description of each developmental and epileptic encephalopathy, but to discuss recent changes in the terminology and diagnostic criteria of specific disorders, based on an updated review of the last 10 years. Important changes in the definitions of specific syn dromes and new treatments that have shown efficacy in the management of seizures in these patients are analyzed. In conclusion: New gene modulation therapy will likely improve not only seizure frequency, but also cog nitive outcome and therefore quality of life.
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Objective:To explore risk factors for clinical onset in children with uncontrolled self-limited epilepsy with centrotemporal spikes (SeLECTS) managed by 2 anti-seizure medications (ASMs).Methods:A total of 112 children with SeLECTS who were diagnosed at the Department of Pediatric Neurology of the Third Affiliated Hospital of Zhengzhou University from January 2018 to May 2021 were retrospectively reviewed.All of them were treated with conventional ASMs, and regularly followed up for 1-2 years.Types of therapeutic drugs, clinical seizure control status, presence of new seizure forms, electroencephalogram (EEG) were reviewed at follow-up visits.According to whether the seizures were controlled after the use of no more than 2 ASMs, patients were divided into poor response group (43 cases) and good response group (69 cases), and their clinical data and EEG characteristics were compared.Multivariate Logistic regression analysis was used to explore the risk factors for seizures that were uncontrolled by 2 ASMs. Results:There were significant differences in the age of onset ( χ2=8.919, P=0.003), seizure form ( χ2=4.218, P=0.040), seizure frequency ( Z=-7.664, P<0.001), EEG background slowing ( χ2=10.284, P=0.001), emergence of electrical status epilepticus during slow-wave sleep (ESES)( χ2=11.921, P=0.001), discharge generalization ( χ2=25.377, P<0.001), and presence of epileptic encephalopathy with spike-and-wave activation in sleep (EE-SWAS)( χ2=54.334, P<0.001) between groups.Multivariate Logistic regression analysis showed that seizure frequency ( P<0.001, OR=0.086, 95% CI: 0.022-0.329), discharge generalization ( P=0.006, OR=9.942, 95% CI: 1.918-51.527) and EEG background slowing ( P=0.041, OR=6.648, 95% CI: 1.077-41.038) were the 3 main risk factors associated with poor response to short-term medications of ASMs. Conclusions:Seizures are easily controlled in most SeLECTS patients medicated with ASMs with a favorable prognosis.Seizure frequency, discharge generalization and EEG background slowing are risk factors for the poor response to short-term pharmacotherapy in children with SeLECTS.
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Objective:To understand the genome sequence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and spike protein variations during different epidemic periods in Wuxi City.Methods:Nucleic acid was extracted from the nasopharyngeal swab samples of six local cases of coronavirus disease 2019 (COVID-19) (from January to February, 2020) and 13 imported cases of COVID-19 (from March to September, 2021) in Wuxi City, and the whole genome was amplified to construct the sequencing library. The second-generation sequencer was used for sequencing. The CLC Genomics Workbench (21 version) software was used to analyze the offline data with NC_045512.2 as the reference strain, and MEGA 7.0 software was used to construct the phylogenetic tree.Identification of type was conducted by Nextstrain typing method and phylogenetic assignment of named global outbreak lineages (Pangolin) typing method.Results:There were five subtypes in Nextstrain and seven subtypes in Pangolin of the nineteen patients with COVID-19. Compared with NC_045512.2, the median nucleotide mutation sites were 29 (range 0 to 42) and amino acid mutation sites were 20 (range 0 to 34). The six local and 13 imported cases had no common nucleotide mutation sites and were in different evolutionary branches. The sequences of the six local cases were highly homologous with the reference strain sequences (NC_045512.2) at the early stage of the pandemic, and the evolutionary distance was close to that of the reference strain. The 13 imported cases were obviously divided into three evolutionary branches (Alpha, Beta, Delta variant).The four Beta variants shared eight amino acid mutation sites in spike protein, and the two Alpha variants shared eight amino acid mutation sites in spike protein, and the seven Delta variants shared five amino acid mutation sites in spike protein.Conclusions:New mutations of SARS-CoV-2 are constantly emerging during the epidemic. The increase of the nucleotide sites number may result in the change of spike protein amino acid. Therefore, the whole-genome sequencing analysis plays an important role in the accurate tracing of epidemic origin and adjustment of prevention and control measures.
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Objective:To observe the inhibition of SARS-CoV-2 spike protein (S-protein) on the proliferation of human retinal pigment epithelium (RPE) cells.Methods:SARS-CoV-2 S-protein gene fragment expression plasmid (p3xflag-S) was constructed and transfected into human RPE, HEK293 cells. DNA sequencing was used for identification, and the expression of Flag-S was detected by Western blot. HEK293 cells were divided into the cells 1, 2, 3 and 4 and transfected with GFP11 plasmid and vector, GFP1-10 plasmid and vector, transfected with GFP11 and pCMV-HA-ACE2 plasmid, GFP1-10 and p3xflag-S plasmid. Cell 1 was co-cultured with cell 2 (control group 1), cell 2 with cell 3 (control group 2), cell 3 with cell 4 (observation group), and cell 1 mixed with cells 2, 3 and 4 (control group 3). Bright-field microscopy and fluorescence microscopy were used to observe cell fusion. RPE cells were divided into control group and overexpression S-protein group. The cell cycle was detected by flow cytometry; the cell proliferation level was detected by Counting Kit 8 (CCK-8); and the S-protein expression level in RPE cells was detected by Western blot. The Student’s t-test was performed for comparison between groups. Results:DNA sequence assay showed that S-protein cDNA was fused with flag-tagged protein. Western blot assay showed that S-protein-related expression was elevated in transfected HEK293 cells compared with untransfected p3xflag-S cells. Large, multinucleated fused cell clusters were visible under bright-field microscopy; multiple nuclear with distinct green fluorescence were visible in the fused cells under fluorescence microscopy. Western blot assay showed elevated S-protein-related expression in transfected p3xflag-S plasmid RPE cells compared to untransfected p3xflag-S plasmid RPE cells. CCK-8 results showed that the proliferative capacity of RPE cells in the S-protein overexpression group was significantly reduced compared with the control group, with statistically significant differences ( t=22.70, 16.75, 23.38; P<0.000 1). The results of flow cytometry showed that the G1 phase cells in the control and overexpression S-protein groups were 41.1 % and 67.0%, respectively; compared with the control group, the G1 phase cells in the overexpression S-protein group were significantly higher, and the difference was statistically significant ( t=4.76, P=0.018). The apoptosis rate was significantly increased in the S-protein overexpression group compared with the control group, and the difference was statistically significant ( t=4.91, P=0.008). Conclusion:Overexpression of the SARS-CoV-2 spike protein reduced the proliferation of human RPE cells.
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@#Since the first case of corona virus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the end of 2019, the virus has spread rapidly around the world and has become a global public health problem. In the process of this virus epidemic, compared with the general population, cancer patients are considered to be highly susceptible people, especially the lung cancer patients. Some studies have shown that angiotensin converting enzyme 2 (ACE2) may be the pathway for SARS-CoV-2 to infect the host. At the same time, ACE2 is often abnormally expressed in non-small cell lung cancer. Therefore, understanding the respective mechanisms of ACE2 in COVID-19 and non-small cell lung cancer has extremely important reference value for the study of vaccines and therapeutic drugs, and also provides meaningful guidance for the protection of patients with lung cancer during the epidemic. This article reviews the possible invasive mechanism of ACE2 in SARS-CoV-2 and its abnormal expression in non-small cell lung cancer.
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OBJECTIVE@#Late 2019 witnessed the outbreak and widespread transmission of coronavirus disease 2019 (COVID-19), a new, highly contagious disease caused by novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Consequently, considerable attention has been paid to the development of new diagnostic tools for the early detection of SARS-CoV-2.@*METHODS@#In this study, a new poly-N-isopropylacrylamide microgel-based electrochemical sensor was explored to detect the SARS-CoV-2 spike protein (S protein) in human saliva. The microgel was composed of a copolymer of N-isopropylacrylamide and acrylic acid, and gold nanoparticles were encapsulated within the microgel through facile and economical fabrication. The electrochemical performance of the sensor was evaluated through differential pulse voltammetry.@*RESULTS@#Under optimal experimental conditions, the linear range of the sensor was 10 -13-10 -9 mg/mL, whereas the detection limit was 9.55 fg/mL. Furthermore, the S protein was instilled in artificial saliva as the infected human saliva model, and the sensing platform showed satisfactory detection capability.@*CONCLUSION@#The sensing platform exhibited excellent specificity and sensitivity in detecting spike protein, indicating its potential application for the time-saving and inexpensive detection of SARS-CoV-2.
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Humanos , Microgéis , Glicoproteína da Espícula de Coronavírus , COVID-19/diagnóstico , Ouro , Nanopartículas Metálicas , SARS-CoV-2RESUMO
@#Objective To construct a single-chain fragment variable(scFv)phage display library against receptor-binding domain(RBD)of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)spike protein(S)to screen specific scFv and identify the function.Methods m RNA was extracted from spleen cells of mice immunized with RBD protein and reversely transcribed into c DNA,with which as template,genes of the hight chain fragment of variable(VH)and light chain fragment of variable(VL)of scFv were amplified and then assembled into scFv gene fragment through splicing overlap extension PCR(SOE-PCR).The scFv gene fragment was inserted to phage vector to construct scFv phage display library.After four rounds of biopanning,the scFv gene with strong binding ability to RBD was screened and expressed recombinantly,purified and identified for biological activity.Results The constructed scFv phage library showed a titer of 6.0×10(11)pfu/m L.After four rounds of biopanning,four scFv strains with strong binding to RBD were selected,namely scFv11,scFv12,scFv25and scFv28.scFv was mainly expressed in the form of inclusion body with a relative molecular mass of about 27 000,a concentration of 2.4 mg/m L and a purity of about 90%,which bound specifically to mouse monoclonal antibody against His labeled by HRP after purification.All four scFv strains bound specifically to RBD recombinant protein,among which the other 3 scFv strains bound to the S protein of wild type and multiple mutant strains except scFv28.All four strains showed dose-dependent interaction with RBD,with affinity dynamic fitting dissociation constants(K_Ds)8.9,5.92,10.67and 2.36 nmol/L,and steady-state fitting dissociation constants(K_Ds)of 5.3,6.5,8.7 and 5.8 nmol/L,respectively.scFv11,scFv12 and scFv25 simultaneously identified three independent RBD polypeptides,including RBD2(S(11)pfu/m L.After four rounds of biopanning,four scFv strains with strong binding to RBD were selected,namely scFv11,scFv12,scFv25and scFv28.scFv was mainly expressed in the form of inclusion body with a relative molecular mass of about 27 000,a concentration of 2.4 mg/m L and a purity of about 90%,which bound specifically to mouse monoclonal antibody against His labeled by HRP after purification.All four scFv strains bound specifically to RBD recombinant protein,among which the other 3 scFv strains bound to the S protein of wild type and multiple mutant strains except scFv28.All four strains showed dose-dependent interaction with RBD,with affinity dynamic fitting dissociation constants(K_Ds)8.9,5.92,10.67and 2.36 nmol/L,and steady-state fitting dissociation constants(K_Ds)of 5.3,6.5,8.7 and 5.8 nmol/L,respectively.scFv11,scFv12 and scFv25 simultaneously identified three independent RBD polypeptides,including RBD2(S(334～353)),RBD9(S(334～353)),RBD9(S(439～458))and RBD13(S(439～458))and RBD13(S(499～518)).Homologous model of scFv constructed by online server SWISS-MODEL showed a good quality and was used for molecular docking.The interface at which scFv11 interacted with RBD only partially coincided with the interaction interface of human angiotensin converting enzyme 2(ACE2)and RBD,and the interaction interfaces of scFv12 and scFv25 with RBD were quite different from that of ACE2.Conclusion In this study,scFv specifically bound to SARS-Co V-2 RBD was screened and prepared through constructing scFv phage library against SARS-CoV-2 RBD,which provided experimental basis for further development of anti-SARS-CoV-2 drugs and detection reagents.
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Via an insufficient coat protein complex I (COPI) retrieval signal, the majority of SARS-CoV-2 spike (S) is resident in host early secretory organelles and a tiny amount is leaked out in cell surface. Only surface-exposed S can be recognized by B cell receptor (BCR) or anti-S therapeutic monoclonal antibodies (mAbs) that is the trigger step for B cell activation after S mRNA vaccination or infected cell clearance by S mAbs. Now, a drug strategy to promote S host surface exposure is absent. Here, we first combined structural and biochemical analysis to characterize S COPI sorting signals. A potent S COPI sorting inhibitor was then invented, evidently capable of promoting S surface exposure and facilitating infected cell clearance by S antibody-dependent cellular cytotoxicity (ADCC). Importantly, with the inhibitor as a probe, we revealed Omicron BA.1 S is less cell surface exposed than prototypes because of a constellation of S folding mutations, possibly corresponding to its ER chaperone association. Our findings not only suggest COPI is a druggable target against COVID-19, but also highlight SARS-CoV-2 evolution mechanism driven by S folding and trafficking mutations.
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Objective:To analyze the video electroencephalogram (VEEG) and clinical features of simultaneous or sequential onset of childhood absence epilepsy (CAE) and childhood benign epilepsy with centrotemporal spikes (BECTS).Methods:Seven patients with simultaneous or sequential onset of CAE and BECTS admitted to Neurology Center, Beijing Tiantan Hospital from January 2016 to July 2023 were chosen. The clinical features, VEEG, treatments and prognoses of these patients were retrospectively analyzed. PubMed database was searched for articles on simultaneous or sequential onset of CAE and BECTS from January 2002 to July 2023, and studies with 3 or more cases of simultaneous or sequential onset of CAE and BECTS were included. Clinical characteristics of these patients in various studies were compared.Results:(1) The mean onset age in these 7 patients was 6.28 years, ranged from 4 to 8 years. CAE was recorded in 2 patients without clinical manifestation of BECTS during the course of disease progression; simultaneous or sequential onset of CAE and BECTS was recorded in 5 patients. Of the 7 patients, 2 effectively accepted valproate sodium (VPA) monotherapy, and 5 required additional antiepileptic drugs. Although all patients had well-controlled seizures and no developmental delays, 3 had learning disabilities, 3 had attention deficit hyperactivity disorder (ADHD), and 2 had anxiety. Wechsler Intelligence Scale for Children-III (WAIS-III) showed that 1 patient had below average intelligence and 6 had average intelligence. VEEG of all 7 patients showed simultaneous or sequential absence seizures and centrotemporal spikes. (2) Four studies were included in PubMed database. Combined with our study, these 5 sutdies indicated significant differences in onset age in patients with simultaneous or sequential onset of CAE and BECTS ( P<0.05), but no significant differences in simultaneous VEEG manifestations occurred or not and disease comorbidities or not in CAE and BECTS patients ( P>0.05). Conclusion:Patients with simultaneous or sequential onset of CAE and BECTS have different onset age, good overall prognosis and good response to anti-epileptic drugs, and trend to have complicated cognitive impairment.
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Objective To establish a"quality-quantity"double standard control method of Schizonepeta Spike based on the reference material without relying on multiple reference substances.Methods HPLC technology was used to establish the characteristic atlas of Schizonepeta Spike based on the reference traditional Chinese medicinal materials.The chemical constituents of common peaks were identified by Q-TOF-MS technology,and the authenticity of Schizonepeta Spike was determined by the similarity of characteristic peaks of the reference traditional Chinese medicinal materials and the tested traditional Chinese medicinal materials.The relative content of each characteristic peak in different batches of the tested traditional Chinese medicinal materials was calculated by accurate quantition of pulegone.The"Average value-Standard deviation"was taken as the lower limit of the relative content of characteristic peak chemical components relative to pulegone,and the quality of Schizonepeta Spike was determined according to the lower limit of the relative content of characteristic peak.Results The characteristic atlas and content determination method met the requirements of methodology investigation.A total of 11 common chromatographic peaks were determined,and 6 chemical components were identified,which were luteolin,hesperidin,luteolin-7-O-glucuronide,luteolin,geranyl,pulegone.The similarity between the tested traditional Chinese medicinal materials and reference traditional Chinese medicinal materials was greater than 0.90.The lower limit of relative content of chemical components of Schizonepeta Spike characteristic peak was defined.Conclusion The method can identify Schizonepeta Spike clearly and quickly without many reference substances,and provide reference for quality control of Schizonepeta Spike.
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@#Electrical status epilepticus is a special electroencephalogram phenomenon，which means that the spike and slow waves are almost continuously emitted during the wake-sleep phases. Related concepts are epileptic encephalopathy with electrical status epilepticus during slow wave sleep，electrical status epilepticus in sleep，and subclinical electrographic seizures. The above related concepts are widely used in clinical practice，but there is a lack of unified criteria. There are abuses and misuses of these concepts. Clarifying related concepts is of great significance for scientific research and clinical practice.
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@#Objective Spike and wave index (SWI) is of great importance for the diagnosis of electrical status epilepticus during sleep (ESES) in children patients. This study intended to compare four commonly used SWI methods with full night SWI to evaluate their performances. Methods Fifteen patients diagnosed with ESES by electroencephalogram initial report (SWI≥50%) were retrospectively analyzed,and SWI was calculated for the full night sleep(SWI),the first sleep cycle (SWI1),the first 5 minutes of the first sleep cycle (SWI15 min),the first 10 minutes (SWI10 min) and the first 15 minutes (SWI15 min). Wilcox paired test was used to compare SWI with other four SWI methods respectively. Results The SWI of all four methods was significantly different from the full night SWI (p-values of 0.003、0.002、0.002和0.001,respectively,α=0.0125). Among the 15 patients,14 (93.3%) had the trend that SWI decreased with sleep cycles overnight. Conclusion None of the four methods of SWI is a good substitute for full night SWI. The SWI tends to decrease with sleep cycles overnight,and using the first sleep cycle or anepoch of it to calculate SWI is likely to be overestimated.
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COVID-19 is caused by coronavirus SARS-CoV-2. Current systemic vaccines generally provide limited protection against viral replication and shedding within the airway. Recombinant VSV (rVSV) is an effective vector which inducing potent and comprehensive immunities. Currently, there are two clinical trials investigating COVID-19 vaccines based on VSV vectors. These vaccines were developed with spike protein of WA1 which administrated intramuscularly. Although intranasal route is ideal for activating mucosal immunity with VSV vector, safety is of concern. Thus, a highly attenuated rVSV with three amino acids mutations in matrix protein (VSVMT) was developed to construct safe mucosal vaccines against multiple SARS-CoV-2 variants of concern. It demonstrated that spike protein mutant lacking 21 amino acids in its cytoplasmic domain could rescue rVSV efficiently. VSVMT indicated improved safeness compared with wild-type VSV as the vector encoding SARS-CoV-2 spike protein. With a single-dosed intranasal inoculation of rVSVΔGMT-SΔ21, potent SARS-CoV-2 specific neutralization antibodies could be stimulated in animals, particularly in term of mucosal and cellular immunity. Strikingly, the chimeric VSV encoding SΔ21 of Delta-variant can induce more potent immune responses compared with those encoding SΔ21 of Omicron- or WA1-strain. VSVMT is a promising platform to develop a mucosal vaccine for countering COVID-19.
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@#Chikungunya virus (CHIKV) is a neglected tropical pathogen that causes fever and long-lasting severe arthralgia. Despite its high morbidity, there is still no licensed specific therapeutic option for it. This study proposes a multi-epitope subunit vaccine candidate for CHIKV, designed using computational methods. It was based on the E2 spike glycoprotein in CHIKV, from which T- and B-cell epitopes were predicted and then refined. The pan HLA DR-binding epitope (PADRE) was added to this refined construct, then simulated compared with the native protein, where it was predicted to elicit more than twice the number of antibody titers. Thus, this construct is potentially effective against CHIKV, which further experimentation using live models would be able to verify. This study also demonstrates the feasibility of using rational tools in the future to further optimize vaccine design.
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Background & objectives: COVID-19 has been a global pandemic since early 2020. It has diverse clinical manifestations, but consistent immunological and metabolic correlates of disease severity and protection are not clear. This study was undertaken to compare seropositivity rate, antibody levels against nucleocapsid and spike proteins, virus neutralization and metabolites between adult and child COVID-19 patients. Methods: Plasma samples from naïve control (n=14) and reverse transcription (RT)-PCR positive COVID-19 participants (n=132) were tested for reactivity with nucleocapsid and spike proteins by ELISA, neutralization of SARS-CoV-2 infectivity in Vero cells and metabolites by 1H nuclear magnetic resonance (NMR) spectroscopy. Results: An ELISA platform was developed using nucleocapsid and spike proteins for COVID-19 serosurvey. The participants showed greater seropositivity for nucleocapsid (72%) than spike (55.3%), and males showed higher seropositivity than females for both the proteins. Antibody levels to both the proteins were higher in intensive care unit (ICU) than ward patients. Children showed lower seropositivity and antibody levels than adults. In contrast to ICU adults (81.3%), ICU children (33.3%) showed lower seropositivity for spike. Notably, the neutralization efficiency correlated with levels of anti-nucleocapsid antibodies. The levels of plasma metabolites were perturbed differentially in COVID-19 patients as compared with the naive controls. Interpretation & conclusions: Our results reflect the complexity of human immune response and metabolome to SARS-CoV-2 infection. While innate and cellular immune responses are likely to be a major determinant of disease severity and protection, antibodies to multiple viral proteins likely affect COVID-19 pathogenesis. In children, not adults, lower seropositivity rate for spike was associated with disease severity
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SARS-CoV-2 pandemic has become a major threat to human healthcare and world economy. Due to the rapid spreading and deadly nature of infection, we are in a situation to develop quick therapeutics to combat SARS-CoV-2. In this study, we have adopted a multi-level scoring approach to identify multi-targeting potency of bioactive compounds in selected medicinal plants and compared its efficacy with two reference drugs, Nafamostat and Acalabrutinib which are under clinical trials to treat SARS-CoV-2. In particular, we employ molecular docking and implicit solvent free energy calculations (as implemented in the Molecular Mechanics -Generalized Born Surface Area approach) and QM fragmentation approach for validating the potency of bioactive compounds from the selected medicinal plants against four di?erent viral targets and one human receptor (Angiotensin-converting enzyme 2 -ACE-2) which facilitates the SARS-CoV-2entry into the cell. The protein targets considered for the study are viral 3CL main protease (3CLpro), papain-like protease (PLpro), RNA dependent RNA polymerase (RdRp), and viral spike protein-human hACE-2 complex (Spike:hACE2)including human protein target (hACE-2). Herein, thereliable multi-level scoring approach was used to validate the mechanism behind the multi-targeting potency of selected phytochemicals from medicinal plants. The present study evidenced that the phytochemicals Chebulagic acid, Stigmosterol, Repandusinic acid and Geranin exhibited efficient inhibitory activity against PLpro while Chebulagic acid was highly active against 3CLpro. Chebulagic acid andGeranin also showed excellent target specific activity against RdRp.Luteolin, Quercetin, Chrysoeriol and Repandusinic acid inhibited the interaction of viral spike protein with human ACE-2 receptor. Moreover Piperlonguminine and Piperine displayed significant inhibitory activity against human ACE-2 receptor. Therefore, the identified compounds namely Chebulagic acid, Geranin and Repandusinic acid can serve as potent multi-targeting phytomedicine for treating COVID-19
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Resumen El coronavirus del Síndrome Respiratorio Agudo Grave 2 (SARS-CoV-2) posee diversas proteínas estructurales que incluyen la proteína spike (S), principal blanco de las vacunas actuales. Existen diversas metodologías para la medición de anticuerpos contra ésta que brindan información acerca de la respuesta inmune frente a la vacunación. El objetivo de este trabajo fue determinar la correlación entre quimioluminiscencia (CLIA) y enzimoinmunoanálisis de adsorción (ELISA) para la medición de anticuerpos IgG anti-proteína S (IgG anti-S). Se recolectaron resultados serológicos de 169 individuos y se determinaron los niveles de anticuerpos por ambas metodologías. Del total de muestras, 106 arrojaron un resultado positivo por ambas metodologías y 15 resultaron discordantes (CLIA+, ELISA-), con índice Kappa de 0,80. La correlación entre ambas metodologías fue buena. Este estudio podría aportar al manejo y seguimiento de la población vacunada, con la finalidad de obtener un valor de corte para evaluar la aplicación de una dosis adicional.
Abstract Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) has several structural proteins including the spike (S) protein, which is the main target of current vaccines. There are various methodologies for the measurement of antibodies against it that provide information about the immune response to vaccination. The objective of this study was to determine the correlation between chemiluminescence (CLIA) and enzyme-linked immunoassay (ELISA) for the measurement of IgG anti-S protein (IgG anti-S) antibodies. Serological results were collected from 169 individuals and antibody levels were determined by both methodologies. Out of the total samples, 106 were positive by both methodologies and 15 were discordant (CLIA+, ELISA-), with a Kappa index of 0.80. The correlation between both methodologies was good. This study could contribute to the management and follow-up of the vaccinated population, in order to obtain a cut-off value to evaluate the application of an additional dose.
Resumo O coronavírus da Síndrome Respiratória Aguda Grave 2 (SARS-CoV-2) possui várias proteínas estruturais, incluindo a proteína spike (S), principal alvo das vacinas atuais. Existem várias metodologias para medir anticorpos contra ela que fornecem informações sobre a resposta imune diante da vacinação. O objetivo deste trabalho foi determinar a correlação entre quimioluminescência (CLIA) e enzimoimunoanálise de absorção (ELISA) para a medição de anticorpos IgG anti-proteína S (IgG anti-S). Foram coletados resultados sorológicos de 169 indivíduos e os níveis de anticorpos foram determinados por ambas as metodologias. Do total de amostras, 106 deram resultados positivos nas duas metodologias e 15 foram discordantes (CLIA+, ELISA-), com índice Kappa de 0,80. A correlação entre as duas metodologias foi boa. Este estudo poderia contribuir para a gestão e seguimento da população vacinada, visando a obter um valor de corte para avaliar a aplicação de uma dose adicional.