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Abstract This work aimed to show which treatments showed efficacy against coronavirus disease 2019 (COVID-19); therefore, the results of 37 clinical trials started in 2020 and completed in 2021 are reviewed and discussed here. These were selected from databases, excluding vaccines, computational studies, in silico, in vitro, and those with hyperimmune sera from recovered patients. We found 34 drugs, one vitamin, and one herbal remedy with pharmacological activity against symptomatic COVID-19. They reduced mortality, disease progression, or recovery time. For each treatment, the identifier and type of trial, the severity of the disease, the sponsor, the country where the trial was conducted, and the trial results are presented. The drugs were classified according to their mechanism of action. Several drugs that reduced mortality also reduced inflammation in the most severe cases. These include some that are not considered anti-inflammatory, such as Aviptadil, pyridostigmine bromide, anakinra, imatinib, baricitinib, and bevacizumab, as well as the combination of ivermectin, aspirin, dexamethasone, and enoxaparin. Nigella sativa seeds with honey have also been reported to have therapeutic activity. On the other hand, tofacitinib, novaferon with ritonavir, and lopinavir were also effective, as well as in combination with antiviral therapies such as danoprevir with ritonavir. The natural products colchicine and Vitamin D3 were only effective in patients with mild-to-moderate COVID-19, as was hydroxychloroquine. Drug repositioning has been the main tool in the search for effective therapies by expanding the pharmacological options available to patients.
Resumen El objetivo del presente trabajo fue conocer qué tratamientos mostraron efectividad contra COVID-19, para lo cual se revisan y discuten los resultados de 37 estudios clínicos iniciados durante 2020 y concluidos en 2021. Estos fueron seleccionados de bases de datos, excluyendo vacunas, estudios computacionales, in silico, in vitro y con sueros hiperinmunes de pacientes recuperados. Se documentaron 34 fármacos, una vitamina y un remedio herbolario, con actividad farmacológica ante COVID-19 sintomático. Estos redujeron la mortalidad, el progreso de la enfermedad, o el tiempo de recuperación. Para cada tratamiento se presenta identificador y tipo de estudio, la gravedad de la enfermedad, patrocinador, país donde se realizó, así como sus resultados. Los fármacos se clasificaron de acuerdo con su mecanismo de acción. Varios fármacos que redujeron la mortalidad también disminuyeron la inflamación en los casos más graves. Esto incluyendo algunos no considerados antiinflamatorios, como el aviptadil, el bromuro de piridostigmina, el anakinra, el imatinib, el baricitinib y el bevacizumab, así como la combinación de ivermectina, aspirina, dexametasona y enoxaparina. También se reportaron con actividad terapéutica las semillas de Nigella sativa con miel. Además, resultaron efectivos el tofacitinib, el novaferón con ritonavir y lopinavir, así como los antivirales en terapias combinadas como el danoprevir con ritonavir. Los productos naturales colchicina y vitamina D3, solo tuvieron actividad en los pacientes en estado leve a moderado de la COVID-19, así como la hidroxicloroquina. El reposicionamiento de fármacos fue la principal herramienta para buscar terapias efectivas ampliando las opciones farmacológicas accesibles a los pacientes.
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Multisystem inflammatory syndrome in children (MIS-C) is a complex syndrome characterized by multi-organ involvement that has emerged in the context of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak. The clinical presentation of MIS-C is similar to Kawasaki disease but predominantly presents with fever and gastrointestinal symptoms, and severe cases can involve toxic shock and cardiac dysfunction. Epidemiological findings indicate that the majority of MIS-C patients test positive for SARS-CoV-2 antibodies. The pathogenesis and pathophysiology of MIS-C remain unclear, though immune dysregulation following SARS-CoV-2 infection is considered a major contributing factor. Current treatment approaches for MIS-C primarily involve intravenous immunoglobulin therapy and symptomatic supportive care. This review article provides a comprehensive overview of the definition, epidemiology, pathogenesis, clinical presentation, diagnosis, treatment, and prognosis of MIS-C.
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Niño , Humanos , COVID-19 , SARS-CoV-2 , Pandemias , Síndrome de Respuesta Inflamatoria Sistémica/terapiaRESUMEN
ObjectiveThis study explored the application of Yiqi Zengmian prescription as a vaccine adjuvant， aiming to provide a new scheme for the prevention and control of corona virus disease 2019（COVID-19） with traditional Chinese medicine （TCM）. By analyzing the compatibility and efficacy， this paper examines the compatibility effect of Yiqi Zengmian prescription， which is modified from the classic tonifying agent Si Junzitang， as a vaccine adjuvant. MethodUsing the Database of Ancient Classical Prescriptions， this paper analyzed the composition of Yiqi Zengmian prescription and probed into the theoretical basis for the compatibility of this prescription from the properties， medicine combination， and efficacy. Furthermore， the compatibility effect of this prescription with vaccines was analyzed. ResultAs a TCM prescription， Yiqi Zengmian prescription focuses on the lung and spleen and enhances the Qi in the two organs. The lung governs Qi movement. The body breathes fresh air through the lungs and exchanges the turbid gas in the lungs， and the gas circulates alternately in the lungs to ensure the normal breathing of the human body. The spleen governing transportation and transformation is the hub for Qi movement， and Qi is the embodiment of metabolic function. By regulating qi movement and enhancing the functions of Qi and blood， Yiqi Zengmian prescription can enhance the immunogenicity of the vaccine， which provides a theoretical basis for enhancing the immune effects of vaccines. ConclusionYiqi Zengmian prescription has the effects of replenishing Qi and invigorating spleen， regulating Qi and drying dampness， and enhancing immunity. The in-depth analysis of the TCM theory of Yiqi Zengmian prescription as a vaccine adjuvant and the results of clinical and laboratory studies suggest that Yiqi Zengmian prescription may enhance the induction of immune response after vaccination and maintain the immune memory. However， the mechanism of Yiqi Zengmian prescription in regulating the complex immune network remains to be elucidated.
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Objectives: In December 2019, coronavirus disease 2019 (COVID-19) was first identified in Wuhan, China, as a respiratory tract infection causing symptoms, such as fever, chills, dry cough, fatigue, and shortness of breath. Despite the low mortality rate of COVID-19, patients with comorbidities such as hypertension, cardiovascular disease, and diabetes mellitus seem to be prone to more severe symptoms and to a higher mortality rate than others. Such patients are shown to benefit from usage of monoclonal antibodies. Casirivimab-imdevimab is a cocktail made up of two non-competing, neutralizing human immunoglobulin G1 antibodies that target the receptor binding domain of the severe acute respiratory syndrome coronavirus 2 spike protein and block viral entry into human cells. We assessed the clinical profile and outcome of 42 patients who received the antibody cocktail. Materials and Methods: Casirivimab-imdevimab was administered to COVID-positive patients with mild severity. Forty-two patients who satisfied the inclusion criteria received casirivimab-imdevimab and were included in the study. Demographic and clinical data were tabulated in Microsoft Excel and statistics were run in OpenEpi software. Results: No adverse reactions were seen in any of the patients. Among the 42 patients, there were no deaths. Twentytwo (52.3%) patients improved, while 20 (47.6%) worsened after receiving the antibody cocktail. Out of 21 (50%) patients who did not have any comorbidity, 13 (30.9%) worsened after receiving the drug and 8 (19%) improved, while among those with comorbidities, 7 (16.6%) worsened and 14 (33.3%) improved (P < 0.05). Thirteen (30.9%) unvaccinated patients improved, while 14 (33.3%) worsened, whereas 6 (14.2%) fully vaccinated patients improved while only 2 (4.7%) worsened. Among the patients who were administered the cocktail within 5 days of onset of symptoms, 12 (28.5%) improved and 10 (23.8%) worsened, whereas among those who received the drug between 6 and 10 days of symptom onset, ten improved, and ten worsened. There was no statistically significant association between vaccination status and outcome, and infusion interval and outcome in these patients. Conclusion: None of the 42 patients developed any reaction to casirivimab-imdevimab. There were no deaths in the study population. About 52.3% of the patients improved and 47.6% worsened after receiving the cocktail. About 33.3% of the comorbid patients improved. There was no statistically significant association between vaccination status and outcome, and infusion interval and outcome in these patients.
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Background: Coronavirus 2019 infection (COVID 19) is an ongoing pandemic caused by pathogenic RNA viruses called severe acute respiratory syndrome coronavirus-2 (SARS-COV-2). It has affected people of all ages, with high morbidity and mortality among the elderly and immunocompromised population. Limited information is available on the effects of COVID-19 infection on pregnancy. Aim: To describe the histopathological changes in the placental tissue of SARS-CoV-2 infected term mothers with no comorbidities and to correlate with neonatal outcome. Materials and Methods: This observational study was conducted in the Department of Pathology, KMCH institute of health sciences and research, Coimbatore from May 1, 2020 to November 30, 2020 for 6 months. Placental tissues of all COVID-19-positive term mothers with no comorbidities were included in this study. Histopathological examination of placentae was carried out and clinical data of mothers and newborn babies were obtained from medical records. Results: Histopathological examination of 64 placental tissue of COVID-19 mothers showed predominantly the features of fetal vascular malperfusion like stem villi vasculature thrombus, villous congestion, and avascular villi. No significant correlation was obtained in comparison with parity and symptomatic status of the mothers. However, histopathological changes were more prominent among symptomatic patients. The newborn babies born to these mothers showed no adverse outcome. Conclusion: This study concluded that though COVID-19 infection in normal term pregnant women was associated with increased prevalence of features of fetal vascular malperfusion, there was no significant morbidity in the health status of both COVID-19 mothers and their neonates.
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Introduction: To assess the status of bi-directional screening for COVID-19, tuberculosis and diabetes among people attending Non-communicable Disease (NCD), Directly Observed Treatment Short-course (DOTS), and flu clinics of a secondary care hospital in rural northern India. Material and Methods: A cross?sectional, analytical study was conducted among the eligible (aged ?18 years) population who attended the study clinics in a rural sub-district hospital. In the flu clinic, consecutive patients were assessed for screening for TB (symptom-based) and diabetes (random blood sugar) and status of referral to DOTS and NCD clinics. Similarly, the screening for diabetes and COVID-19, Reverse Transcription-Polymerase Chain Reaction (RT-PCR) in the DOTS clinic, and TB and COVID-19 in the NCD clinic were assessed. The independent association of factors with COVID-19 positivity were assessed by calculating the adjusted prevalence ratios (aPR) at 95% confidence interval (CI). Results: Of the 405 people assessed, 279 (68.9%), 102 (25.2%), and 24 (5.9%) were from flu, NCD, and DOTS clinics, respectively. 26 (25.5%) and 22 (91.7%) of NCD and DOTS clinic patients underwent RT-PCR for COVID-19. TB screening in NCD and flu clinics was done among 4 (3.9%) and 7 (12.5%), respectively. A total of 23 (9.0%) were found positive for COVID-19, and no factors other than the presence of COVID-19 symptoms (aPR: 2.89; 95% CI: 1.33–6.29) had any independent association with COVID-19 positive status. Conclusion: The low screening for TB in NCD and flu clinics indicates the need to strengthen the implementation the TB-DM and TB-COVID-19 bidirectional screening. Similarly, the low screening or testing for COVID-19 in the NCD clinic can be improved by the implementation of systematic screening strategies like TB-DM bidirectional screening.
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Abstract BACKGROUND: Severe acute respiratory syndrome coronavirus 2 has several mechanisms of action related to inflammatory responses, especially in individuals diagnosed with obesity. This hyperinflammatory clinical profile resulting from the association between obesity and coronavirus disease 2019 (COVID-19) may be attenuated by regular physical activity. OBJECTIVE: The aim of this study was to review the evidence on the consequences of physical inactivity and physical activity on COVID-19 in patients with obesity. DESIGN AND SETTING: Narrative review at the Bahiana School of Medicine and Public Health in Salvador, Brazil. METHODS: We searched evidence on the association of COVID-19 with physical activity and obesity using the following keywords: "covid-19," "physical activity," and "obesity". The databases used were MEDLINE (PubMed), ScienceDirect, and Virtual Health Library. Studies published from 2019 to 2021 and available in Portuguese, English, and Spanish were included. The final search was conducted on September 26, 2021. RESULTS: We identified 661 studies in the database, among which 71 were considered for inclusion in the narrative review of the molecular aspects of COVID-19 and its relationship with physical activity and obesity. CONCLUSION: This literature review enabled the perception of the relationship between the molecular mechanisms of COVID-19 and obesity. Regular physical activity had various benefits for the inflammatory condition of the studied population, highlighting moderate-intensity.
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Coronavirus disease-19 (COVID-19), a global epidemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), lead to lung injury in millions of people. SARS-CoV-2 can not only cause cytokine storm, acute respiratory distress syndrome and respiratory failure in the phase of acute infection, but also have potential long-term effects on the lungs. Survivors of severe COVID-19 may develop pulmonary fibrosis, resulting in permanent lung injury. In this review we expound the occurrence and development of COVID-19-related pulmonary fibrosis, summarize the key roles of TGF-p/Smad, TGF-fV MAPK, JAK/STAT, Wnt/(3-catenin, YAP/TAZ, NF-KB and PI3K/Akt signal pathways in this process, and analyze the advantages and disadvantages of antiviral drugs, anti-fibrosis drugs, cytokine-targeted drugs, corticosteroids, spironolactone, traditional Chinese medicine prescriptions and lung transplantation in its treatment. This review may provide a reference for the study of pathological mechanism and clinical treatment of COVID-19-re-lated pulmonary fibrosis.
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@#Objective To evaluate the pharmacodynamics of human interferon(IFN)α1b against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron strain in vitro.Methods Total four drugs human IFNα1b bulk,human IFNα1b eye drops,human IFNα1b spray and Remdesivir were detected for cytotoxicity by CCK-8 assay.The inhibitory effect of human IFNα1b on SARS-CoV-2 Omicron strains(BA.5/BA.2/BA.1)was determined by qPCR.Results Human IFNα1b bulk of the maximum concentration(1 × 107IU/mL)and Remdesivir of the maximum concentration(150 μmol/L)did not achieve half cytotoxicity to Vero cells;The median cytotoxicity concentrations(CC_(50))of human IFNα1b eye drops and human IFNα1b sprays were 29 958 and 37 550 IU/mL,respectively,showing toxicity to Vero cells.The median effective concentrations(EC_(50))of human IFNα1b against virus strains BA.1,BA.2 and BA.5 after incubation for 2 h in advance were 9.30,13.38 and 12.33 IU/mL and those of Remdesivir were 0.314 7,0.291 0 and0.300 3 μmol/L.When incubation with virus simultaneously,the EC_(50)of human IFNα1b to BA.1,BA.2 and BA.5 were19.68,10.91 and 18.84 IU/mL and those of the control drug Remdesivir were 0.320 5,0.274 4 and 0.304 1 μmol/L,respectively.Conclusion At the cell level in vitro,human IFNα1b of very low activity showed a good inhibitory effect on SARS-CoV-2 Omicron strain,which was expected to be a clinical specific drug for the treatment of SARS-CoV-2 Omicron strain infection.
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@#Abstract：Objective To prepare human monoclonal antibody against spike protein（S protein）of severe acute respiratory syndrome coronavirus 2（SARS⁃CoV⁃2）by using single B cell，and determine its neutralizing activity. Methods Venous blood with high antibody level was collected from people immunized with inactivated SARS⁃CoV⁃2 vaccine（Vero cells） twice，of which peripheral blood mononuclear cells（PBMCs）were isolated by lymphocyte stratified fluid and used to isolate single B cell expressing S protein antibody by magnetic beads coupled with S1 protein. Variable region genes of IgG heavy chain and light chain were amplified by nested PCR after reverse transcription of single B cell，which were connected with CMV promoter，IgG leader sequence，IgG constant region and polyA sequence by overlapping PCR to construct antibody linear expression cassette. Linear expression cassette of the heavy chain and light chain from the same B cell was transfected to HEK293T cells to express human monoclonal antibody of SARS⁃CoV⁃2 S protein. Immunoreactivity was detected by immuno⁃ fluorescence while neutralizing activity by pseudovirus neutralization test. Results A total of 26 monoclonal antibodies against SARS⁃CoV⁃2 S protein were expressed，which showed heavy chain and light chain protein bands of IgG antibody at
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Since 2019,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)posed a great threat to human health and social economy, which has brought out hundreds of millions infection and caused millions of deaths worldwide. With the increasing research on SARS-CoV-2, angiotensin-converting enzyme 2(ACE2)has been regarded as a significant functional receptor for SARS-CoV-2 invasion. ACE2 is distributed in many tissues of human body, not only expressed in lung, cardiovascular, kidney tissues, but also in conjunctiva, cornea, uvea, retina and optic nerve tissue. More and more cases of SARS-CoV-2 infection through ocular tissues have been found; however, whether ocular ACE2 plays a role in SARS-CoV-2 infection is not completely clear. Therefore, study on expression and distribution of ACE2 in the ocular tissues can not only provide an in-depth understanding of the mechanism of SARS-CoV-2 infection, but also supply a comprehensive acquaintance with the mechanism of ACE2 action in the ocular tissues. In this paper, we review recent research progress about the expression and distribution of ACE2 in ocular tissues and hope to better understand the mechanism of ACE2 in the pathophysiological processes of ocular tissues.
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【Objective】 To analyze the results of different methods for reactive samples screened by the enzyme linked immunosorbent assay (ELISA) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in blood donors. 【Methods】 From March to April 2020, a total of 8 632 blood samples in Shenzhen were screened for SARS-CoV-2 total antibodies (TAb, including IgG, IgM, IgA) in plasma using ELISA(PC group), the antibody reactivity samples and their follow up plasma samples (FC group), and samples of disease control group(DC group) from January to April 2020 were detected using the following methods: 1) ELISA method for detecting IgG, IgM, and (or without detection) TAb; 2) pseudovirus neutralizing antibody test(pVNT); 3) western blot (WB) of SARS-CoV-2 antibody. The negative control group(NC group) from February to April 2020 performed ELISA and WB testing. 【Results】 Among the 34 total antibody positive samples, 2 were positive for pVNT test, and the total antibody, IgG and WB in the initial screening and tracking testing were positive. Thereafter, it was determined to be confirmed positive. The other 2 cases were positive for pVNT test, while the samples with positive WB results were in the follow-up stage. The TAb, IgG, and pVNT results did not conform to the dynamic evolution of antibodies, and cannot be determined as confirmed positive. 【Conclusion】 The infection status of antibody reactivity samples screened by SARS-CoV-2 ELISA can be judged by the logic of pVNT, WB and the dynamic change of antibody.
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OBJECTIVES@#To investigate the clinical characteristics of children infected with the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Chengdu of China.@*METHODS@#A retrospective analysis was conducted for the clinical data of 226 children who were infected with the Omicron variant of SARS-Cov-2 and were isolated and treated in Chengdu Shelter Hospital from August 28 to September 21, 2022. According to the presence or absence of clinical symptoms, they were divided into two groups: asymptomatic group and mild symptomatic group. The two groups were compared in terms of clinical characteristics, diagnosis and treatment, and prognosis.@*RESULTS@#Among the 226 children infected with the Omicron variant, 71 (31.4%) were asymptomatic and 155 (68.6%) had mild symptoms. Fever and cough were the most common clinical symptoms, with fever in 95 children (61.3%) and cough in 92 children (59.4%). Of all 226 children, 188 (83.2%) received coronavirus disease 2019 (COVID-19) vaccination. The time to nucleic acid clearance ranged from 6 to 26 days, with a nucleic acid clearance rate of 58.0% (131/226). There were no significant differences among different age groups in sex, early symptoms, clinical typing, nucleic acid re-positive rate, nucleic acid clearance rate, and length of hospital stay (P>0.05). There were no significant differences between the asymptomatic and mild symptomatic groups in age, sex, underlying diseases, COVID-19 vaccination, use of Lianhua Qingwen granules, nucleic acid clearance rate, nucleic acid re-positive rate, and length of hospital stay (P>0.05).@*CONCLUSIONS@#Children infected with the Omicron variant of SARS-Cov-2 in Chengdu generally have mild clinical symptoms, mainly upper respiratory tract infection, which has little threat to the health of children of different ages, and children tend to have a good overall prognosis.
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Humanos , Niño , COVID-19 , Vacunas contra la COVID-19 , Tos/etiología , Estudios Retrospectivos , SARS-CoV-2 , China/epidemiología , Fiebre/etiología , Ácidos NucleicosRESUMEN
@#The rapid spread of Coronavirus Disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection has had a devastating impact on public health and the global economy. Tremendous efforts had been put on urgent development of prophylactic or therapeutic drugs against SARS-CoV-2,mainly smallmolecule antiviral drugs and monoclonal antibodies,to reduce the impact and burden of COVID-19. Currently,National Medical Products Administration(NMPA)of China or Food and Drug Administration(FDA)of the United States have approved three small-molecule drugs and three monoclonal antibodies for use. This paper reviews the clinical research progress and challenges of the main drugs against SARS-CoV-2 on the market at present.
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@#Objective To prepare and verify a uniform antigen content detection kit for recombinant protein vaccines against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Methods Using goat anti-S protein polyclonal antibody prepared by National Institutes for Food and Drug Control(NIFDC) as coating antibody,one of four monoclonal antibodies(14C8,15F9,17A7 and 20D8)with high receptor-binding domain(RBD)binding activity and broad-spectrum resistance against major variants as HRP-labeled antibody,a uniform double-antibody sandwich ELISA kit for antigen content detection of recombinant SARS-CoV-2 vaccine was prepared,and the dilution of coating antibody(1∶125 ～ 1∶4 000)and enzymelabeled antibody(1∶250 ～ 1∶32 000)were optimized by chessboard titration. The specificity,linear range,accuracy,precision and durability of the kit were verified. The prepared uniform detection kits were distributed to 12 laboratories to detect15 batches of recombinant SARS-CoV-2 protein vaccine stock solutions(including 11 batches of stock solutions designed with WT strain and 4 batches of designed with Beta,Gamma and Delta variants as reference sequence)from different expression systems(CHO cells,Pichia pastoris,Sf9 cells or E. coli)and target proteins(RBD or S protein)prepared by each laboratory.Results Monoclonal antibody 20D8 was used as the enzyme-labeled antibody with the optimal dilution of 1 : 4 000,and the optimal dilution of coating antibody was 1 : 500. The uniform detection kit showed no cross reaction with recombinant S protein of severe acute respiratory syndrome(SARS)and Middle East respiratory syndrome(MERS). The first generation national standard for recombinant SARS-CoV-2 protein vaccine antigen(national standard for short)showed a concentration of 0. 16 ～ 2. 50 U/mL with a good linear relationship with A450/630,and the linear equation was:y = 0. 791 x-0. 100 4,R2= 0. 993 7;The recoveries of 0. 16 ～ 2. 50 U/mL national standard in 6 repeated tests were 95% ～ 104% and the coefficients of variation(CVs)were less than 15%;The CVs in 3 repeated tests by 2 experimenters at different time were 4. 4% ～6. 6% and the recoveries were in the range of 80% ～ 120% under different temperature and time conditions. The antigen content of 15 batches of recombinant SARS-CoV-2 protein vaccine stock solutions showed good parallelism with the national standard. Conclusion The uniform detection kit for antigen content developed in this study had good specificity,accuracy,precision and durability,and might be used for the detection of antigen content of recombinant SARS-CoV-2 protein vaccines.
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@#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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@#Coronavirus Disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)seriously threatens human health and public health safety.Vaccination plays an important role in effectively controlling the epidemic situation.More than 150 SARS-CoV-2 vaccines have entered the clinical trial stage and 38 have been approved for emergency use or marketing.Neutralizing antibody level is the main index for evaluation of the immunogenicity of vaccines,but there has been no standardized detection method for SARS-CoV-2 neutralizing antibody till now,which makes it difficult to compare the neutralizing antibody levels among different laboratories and different products horizontally,and seriously restricts the development and evaluation of vaccines and antibody therapeutic drugs.With the rapid sale of the first generation of standards for SARS-CoV-2 antibody and the emergence of variants of concern(VOC)of SARS-CoV-2,WHO and China carried out the development of the second generation of standards simultaneously in 2022.This paper reviews the development and application progress of the standards for SARS-CoV-2 antibody in WHO and China.
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@#Coronavirus Disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)seriously threatens human health and public health safety.Vaccination plays an important role in effectively controlling the epidemic situation.More than 150 SARS-CoV-2 vaccines have entered the clinical trial stage and 38 have been approved for emergency use or marketing.Neutralizing antibody level is the main index for evaluation of the immunogenicity of vaccines,but there has been no standardized detection method for SARS-CoV-2 neutralizing antibody till now,which makes it difficult to compare the neutralizing antibody levels among different laboratories and different products horizontally,and seriously restricts the development and evaluation of vaccines and antibody therapeutic drugs.With the rapid sale of the first generation of standards for SARS-CoV-2 antibody and the emergence of variants of concern(VOC)of SARS-CoV-2,WHO and China carried out the development of the second generation of standards simultaneously in 2022.This paper reviews the development and application progress of the standards for SARS-CoV-2 antibody in WHO and China.
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The emerging of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused COVID-19 pandemic. The first case of COVID-19 was reported at early December in 2019 in Wuhan City, China. To examine specific antibodies against SARS-CoV-2 in biological samples before December 2019 would give clues when the epidemic of SARS-CoV-2 might start to circulate in populations. We obtained all 88,517 plasmas from 76,844 blood donors in Wuhan between 1 September and 31 December 2019. We first evaluated the pan-immunoglobin (pan-Ig) against SARS-CoV-2 in 43,850 samples from 32,484 blood donors with suitable sample quality and enough volume. Two hundred and sixty-four samples from 213 donors were pan-Ig reactive, then further tested IgG and IgM, and validated by neutralizing antibodies against SARS-CoV-2. Two hundred and thirteen samples (from 175 donors) were only pan-Ig reactive, 8 (from 4 donors) were pan-Ig and IgG reactive, and 43 (from 34 donors) were pan-Ig and IgM reactive. Microneutralization assay showed all negative results. In addition, 213 screened reactive donors were analyzed and did not show obviously temporal or regional tendency, but the distribution of age showed a difference compared with all tested donors. Then we reviewed SARS-CoV-2 antibody results from these donors who donated several times from September 2019 to June 2020, partly tested in a previous published study, no one was found a significant increase in S/CO of antibodies against SARS-CoV-2. Our findings showed no SARS-CoV-2-specific antibodies existing among blood donors in Wuhan, China before 2020, indicating no evidence of transmission of COVID-19 before December 2019 in Wuhan, China.
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Humanos , Anticuerpos Antivirales , Donantes de Sangre , China/epidemiología , COVID-19/inmunología , Inmunoglobulina G , Inmunoglobulina M , Pandemias , SARS-CoV-2RESUMEN
AIM: To observe the clinical features of acute macular neuroretinopathy(AMN)induced by Omicron.METHODS: A retrospective study. A total of 9 patients(18 eyes)diagnosed with AMN from December 2022 to January 2023 in the Hospital of Chengdu University of Traditional Chinese Medicine were included. Patients underwent spectral-domain optical coherence tomography(SD-OCT), fundus fluorescein angiography(FFA), fundus photography, autofluorescence(AF), infrared reflectance(IR), optical coherence tomography angiography(OCTA)and multicolor, etc. Furthermore, they were followed up for 1～3mo and observed the prognosis.RESULTS: The initial symptom of the Omicron-induced AMN was the sudden onset of central/paracentral scotoma in the eyes with or without impaired vision and metamorphopsia, and the scotoma could persist for at least 3mo. The image features of AMN are as follows. First, the SD-OCT examination showed the rupture of outer retinal layers, scattered hyperreflective lesions, and atrophy of outer retinal layers. In severe cases, hyperreflective lesions were seen in the inner nuclear layer(INL)or with microcystic cavities under the retinal pigment epithelium(RPE). Second, the OCTA examination demonstrated the decreased blood flow density of the deep capillary plexus(DCP)of the macula. Third, the IR examination showed the weak reflection of lesion areas. Fourth, the fundus photography demonstrated the localized brown wedge-shaped lesion.CONCLUSIONS: The Omicron-induced AMN is mostly found in young females, and the characteristic manifestation of fundus is damage to the outer retinal layers. The extent of fundus lesions is related to the systemic inflammatory response and ocular microcirculatory changes after infection. The multimodal fundus image examination and a history of Omicron infection are helpful to diagnose the Omicron-induced AMN.