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The mortality and hospitalization rate by COVID-19 dropped significantly currently, but its seasonal outbreaks make antiviral treatment still vital. The mortality and hospitazation rate by COVID-19 dropped significantly currently, but its seasonal ourbreaks make antiviral treatment still vital. In our study, syrian golden hamsters were treated with molnupiravir and interferons (IFNs) after SARS-CoV-2 infection. Their weight changes, pathological changes, virus replication and inflammation levels were evaluated. In the IFNs single treatment, only IFN-α group reduced viral load (p < 0.05) and virus titer in hamster lungs. The TNF-α expression decreased significantly in both IFNs treatment at 2dpi. Histological and immunofluorescence results showed lung damage in the IFNs groups were milder at 4dpi. In the molnupiravir/IFN-α combination treatment, weight loss and virus replication in lung were significantly decreased in the mono-molnupiravir group and combination group (p < 0.05), the expression of IL-6, TNF-α, IL-1ß and MIP-1α also decreased significantly (p < 0.05), but the combination treatment was not more effective than the mono-molnupiravir treatment. Histological and immunofluorescence results showed the lung damage and inflammation in mono-molnupiravir and combination groups were milder. In summary, IFNs treatment had anti-inflammatory effect against SARS-CoV-2, only IFN-α showed a weak antiviral effect. Molnupiravir/IFN-α combination treatment was effective against SARS-CoV-2 but was not superior to mono-molnupiravir treatment. IFN-α could be considered for immunocompromised patients to stimulate and activate early immune responses.
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Antivirais , Tratamento Farmacológico da COVID-19 , Hidroxilaminas , Pulmão , Mesocricetus , SARS-CoV-2 , Carga Viral , Replicação Viral , Animais , Antivirais/uso terapêutico , Antivirais/farmacologia , Pulmão/virologia , Pulmão/patologia , Pulmão/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , Carga Viral/efeitos dos fármacos , Hidroxilaminas/uso terapêutico , Hidroxilaminas/farmacologia , Cricetinae , Modelos Animais de Doenças , COVID-19/imunologia , COVID-19/virologia , Citidina/análogos & derivados , Citidina/uso terapêutico , Citidina/farmacologia , Quimioterapia Combinada , Interferon-alfa/uso terapêutico , Interferon-alfa/farmacologia , Citocinas/metabolismo , Interferons/uso terapêutico , Masculino , Leucina/análogos & derivados , Leucina/uso terapêutico , Leucina/farmacologiaRESUMO
Aerobic methane (CH4) oxidation coupled to denitrification (AME-D) is a promising process for the denitrification of low C/N wastewater. Compared with anaerobic denitrifying bacteria, aerobic denitrifying bacteria may enable AME-D have high denitrification ability under aerobic conditions. This study constructed a novel aerobic methane oxidation coupled to aerobic denitrification (AME-AD) system using the typical aerobic denitrifying bacteria Paracoccus pantotrophus ATCC35512 and the typical aerobic methane oxidizing bacteria Methylosinus trichosporium OB3b. The denitrification and CH4 oxidations of AME-AD with different O2:CH4 ratios (0:1, 0.25:1, 0.5:1, 0.75:1, 1:1 and 1.25:1) and CH4 concentrations (0, 14000, 28000, 42000, 56000 and 70000 mg m-3) were investigated in batch experiments. Higher O2:CH4 ratios can significantly improve the denitrification and CH4 oxidations of the AME-AD (P < 0.05). The treatment with an O2:CH4 ratio of 1.25:1 had the highest denitrification rate (0.036 mg h-1) and highest CH4 oxidation rate (0.20 mg h-1). The CH4 concentration in the headspace was positively correlated with the AME-AD denitrification rate. The calculated CH4/NO3-(mol/mol) in most treatments ranged from 5.76 to 6.84. In addition, excessively high O2 and CH4 concentrations can lead to increased nitrous oxide (N2O) production in AME-AD. The N2O production rate was up to 1.00 µg h-1 when the O2:CH4 was 1.25:1. These results can provide data support for the application of AME-AD for low-C/N wastewater treatment and greenhouse gas emission reduction.
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BACKGROUND: The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has lasted for three years. Coinfection with seasonal influenza may occur resulting in more severe diseases. The interaction between these two viruses for infection and the effect of antiviral treatment remains unclear. METHODS: A SARS-CoV-2 and influenza H1N1 coinfection model on Calu-3 cell line was established, upon which the simultaneous and sequential coinfection was evaluated by comparing the viral load. The efficacy of molnupiravir and baloxavir against individual virus and coinfection were also studied. RESULTS: The replication of SARS-CoV-2 was significantly interfered when the influenza virus was infected simultaneously or in advance (p < 0.05). On the contrary, the replication of the influenza virus was not affected by the SARS-CoV-2. Molnupiravir monotherapy had significant inhibitory effect on SARS-CoV-2 when the concentration reached to 6.25 µM but did not show any significant anti-influenza activity. Baloxavir was effective against influenza within the dosage range and showed significant effect of anti-SARS-CoV-2 at 16 µM. In the treatment of coinfection, molnupiravir had significant effect for SARS-CoV-2 from 6.25 µM to 100 µM and inhibited H1N1 at 100 µM (p < 0.05). The tested dosage range of baloxavir can inhibit H1N1 significantly (p < 0.05), while at the highest concentration of baloxavir did not further inhibit SARS-CoV-2, and the replication of SARS-CoV-2 significantly increased in lower concentrations. Combination treatment can effectively inhibit influenza H1N1 and SARS-CoV-2 replication during coinfection. Compared with molnupiravir or baloxavir monotherapy, combination therapy was more effective in less dosage to inhibit the replication of both viruses. CONCLUSIONS: In coinfection, the replication of SARS-CoV-2 would be interfered by influenza H1N1. Compared with molnupiravir or baloxavir monotherapy, treatment with a combination of molnupiravir and baloxavir should be considered for early treatment in patients with SARS-CoV-2 and influenza coinfection.
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Antivirais , COVID-19 , Coinfecção , Dibenzotiepinas , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , SARS-CoV-2 , Carga Viral , Replicação Viral , Antivirais/farmacologia , Antivirais/uso terapêutico , Humanos , SARS-CoV-2/efeitos dos fármacos , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , Coinfecção/tratamento farmacológico , Coinfecção/virologia , Replicação Viral/efeitos dos fármacos , Dibenzotiepinas/uso terapêutico , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , COVID-19/virologia , Carga Viral/efeitos dos fármacos , Piridonas/farmacologia , Piridonas/uso terapêutico , Linhagem Celular , Morfolinas/farmacologia , Morfolinas/uso terapêutico , Triazinas/farmacologia , Triazinas/uso terapêutico , Tratamento Farmacológico da COVID-19 , Hidroxilaminas/farmacologia , Hidroxilaminas/uso terapêutico , Tiazóis/farmacologia , Tiazóis/uso terapêutico , Citidina/análogos & derivadosRESUMO
Palmitoylation of cysteine residues at the C-terminal hypervariable regions in human HRAS and NRAS, which is necessary for RAS signaling, is catalyzed by the acyltransferase DHHC9 in complex with its accessory protein GCP16. The molecular basis for the acyltransferase activity and the regulation of DHHC9 by GCP16 is not clear. Here we report the cryo-electron microscopy structures of the human DHHC9-GCP16 complex and its yeast counterpart-the Erf2-Erf4 complex, demonstrating that GCP16 and Erf4 are not directly involved in the catalytic process but stabilize the architecture of DHHC9 and Erf2, respectively. We found that a phospholipid binding to an arginine-rich region of DHHC9 and palmitoylation on three residues (C24, C25 and C288) were essential for the catalytic activity of the DHHC9-GCP16 complex. Moreover, we showed that GCP16 also formed complexes with DHHC14 and DHHC18 to catalyze RAS palmitoylation. These findings provide insights into the regulatory mechanism of RAS palmitoyltransferases.
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Lipoilação , Saccharomyces cerevisiae , Humanos , Lipoilação/fisiologia , Microscopia Crioeletrônica , Saccharomyces cerevisiae/metabolismo , Aciltransferases/metabolismo , Proteínas de Membrana/metabolismoRESUMO
Maternal separation (MS) is a type of early-life stress that has been linked to neuropsychiatric disorders, especially depression. Increasing evidence indicates that the adenosine triphosphate (ATP) level in the prefrontal cortex (PFC) is involved in the pathophysiology of depression. To investigate the potential relationship between ATP in PFC and antidepressant effects of electroacupuncture (EA) treatment, we assessed genes involved in ATP biosynthesis as well as the extracellular ATP levels in a rat model exposed to neonatal MS. Our results demonstrated that reduced expression of ABCG2 (an ATP-binding cassette protein) and ATP levels in the PFC of depressive-like rats exposed to MS can be attenuated by EA stimulus at the Baihui (GV20) and Yintang (GV29) acupoints. Moreover, the antidepressant effect of EA treatment was blocked by administration of suramin, a broad purinergic P2 receptor antagonist. Together, these results suggested that electroacupuncture may be able to modulate extracellular ATP levels in the PFC of depressive-like MS rats, potentially contributing to its antidepressant effects.
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Eletroacupuntura , Ratos , Animais , Ratos Sprague-Dawley , Eletroacupuntura/métodos , Privação Materna , Córtex Pré-Frontal , Antidepressivos/farmacologiaRESUMO
BACKGROUND Endoscopic submucosal dissection (ESD) has become a preferred treatment method for patients with early esophageal cancer (EEC), but it can easily be complicated by esophageal stricture. In this study, we aimed to analyze the predictive value of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR) for post-ESD esophageal stricture of EEC. MATERIAL AND METHODS A retrospective study of 285 patients with EEC who underwent ESD was conducted. Patients were divided into 2 groups according to whether there were complications of esophageal stricture: the stricture group (n=72) and the non-stricture group (n=213). A t test or chi-squared test was used to compare the clinical differences in different subgroups. Receiver operating characteristic (ROC) curves were plotted to determine and compare the predictive value of NLR, PLR, and MLR in post-ESD esophageal stricture. Spearman correlation was used to detect the relationship between NLR, PLR, and MLR and the severity of esophageal stricture. RESULTS The NLR, PLR, and MLR values in the stricture group were higher than those in the non-stricture group, and there was a positive correlation between NLR and MLR and the severity of stricture according to the Spearman correlation test (P<0.05). ROC analysis showed that the area under the ROC curve value of the combination of NLR, PLR, and MLR (0.850) was higher than the NLR (0.792), PLR (0.774), and MLR (0.768). CONCLUSIONS The combination of NLR, PLR, and MLR could help clinicians to predict post-ESD esophageal stricture in the early stage.
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Ressecção Endoscópica de Mucosa , Neoplasias Esofágicas , Estenose Esofágica , Humanos , Neutrófilos , Monócitos , Estudos Retrospectivos , Estenose Esofágica/etiologia , Ressecção Endoscópica de Mucosa/efeitos adversos , Prognóstico , Linfócitos , Plaquetas , Neoplasias Esofágicas/cirurgiaRESUMO
BACKGROUND: Early antiviral therapy was effective in the treatment of coronavirus disease 2019 (COVID-19). We assessed the efficacy and safety of combined interferon beta-1b and remdesivir treatment in hospitalized COVID-19 patients. METHODS: We conducted a multicentre, prospective open-label, randomized-controlled trial involving high-risk adults hospitalized for COVID-19. Patients were randomly assigned to a 5-day interferon beta-1b 16 million units daily and remdesivir 200 mg loading on day 1 followed by 100 mg daily on day 2 to 5 (combination group), or to remdesivir only of similar regimen (control group) (1:1). The primary endpoint was the time to complete alleviation of symptoms (NEWS2 = 0). RESULTS: Two-hundred and twelve patients were enrolled. The median days of starting treatment from symptom onset was 3 days. The median age was 65 years, and 159 patients (75%) had chronic disease. The baseline demographics were similar. There was no mortality. For the primary endpoint, the combination group was significantly quicker to NEWS2 = 0 (4 vs 6.5 days; hazard ratio [HR], 6.59; 95% confidence interval [CI], 6.1-7.09; P < .0001) when compared to the control group. For the secondary endpoints, the combination group was quicker to negative nasopharyngeal swab (NPS) viral load (VL) (6 vs 8 days; HR, 8.16; 95% CI, 7.79-8.52; P < .0001) and to develop seropositive immunoglobulin G (IgG) (8 vs 10 days; HR, 10.78; 95% CI, 9.98-11.58; P < .0001). All adverse events resolved upon follow-up. Combination group (HR, 4.1 95% CI, 1.9-8.6, P < .0001) was the most significant independent factor associated with NEWS2 = 0 on day 4. CONCLUSIONS: Early treatment with interferon beta-1b and remdesivir was safe and better than remdesivir only in alleviating symptoms, and in shortening viral shedding and hospitalization with earlier seropositivity in high-risk COVID-19 patients. CLINICAL TRIALS REGISTRATION: NCT04647695.
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Antivirais , Tratamento Farmacológico da COVID-19 , COVID-19 , Interferon beta-1b , Idoso , Humanos , Antivirais/efeitos adversos , Antivirais/uso terapêutico , COVID-19/terapia , Interferon beta-1b/administração & dosagem , Interferon beta-1b/uso terapêutico , Estudos Prospectivos , SARS-CoV-2 , Resultado do TratamentoRESUMO
OBJECTIVE: To analyze the clinical features and genetic basis for a Chinese pedigree affected with familial adenomatous polyposis (FAP). METHODS: Clinical information of the patient was collected. Genomic DNA was extracted from peripheral blood sample of the patient and subjected to whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing. RESULTS: The proband, a 33-year-old female, was found to have multiple adenomatous polyps in the intestine. WES revealed that she has harbored a heterozygous variant of the APC gene, namely c.1922dupA (p.N641fs*10), which was unreported previously. Based on the guidelines of the American College of Medical Genetics and Genomics, the variant was predicted to be likely pathogenic. CONCLUSION: The c.1922dupA (p.N641fs*10) variant of the APC gene probably underlay the FAP in this pedigree. Above finding has enabled genetic counseling for this family.
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Proteína da Polipose Adenomatosa do Colo , Polipose Adenomatosa do Colo , Feminino , Humanos , Adulto , Linhagem , Proteína da Polipose Adenomatosa do Colo/genética , Mutação em Linhagem Germinativa , Polipose Adenomatosa do Colo/genética , China , MutaçãoRESUMO
This study aimed to evaluate the impact of mitigation practices (slurry application methods and inhibitors applications) on gas emissions and identify the soil N2O production pathways in cattle slurry applied soil using isotopocule mapping approach. First, we compared the NH3 and N2O emissions of cattle slurry applied soil in a summer maize field experiment in north China plain (NCP) with four treatments: control (CK, no fertilization), slurry application using surface (SA-S), slurry application using band application (BA-S), and chemical fertilizer application using band application (BA-C). Then, an incubation experiment was conducted to investigate the mitigation effect of nitrification inhibitors (dicyandiamide, DCD) and denitrification inhibitors (procyanidins, PC) and their combination (DCD + PC) on gaseous N emissions with slurry applied using incorporation (IA) or surface application (SA) methods. The results showed that the total gaseous N emissions (N2O-N and NH3-N) in field were in the order of SA-S (1534 mg m-2) > BA-S (338 mg m-2) > BA-C (128 mg m-2) > CK (55 mg m-2), and the dominant N loss contributor varied from NH3 in SA-S (â¼89%) to N2O in BA-S (â¼94%) and BA-C (â¼88%). Moreover, the isotopocule mapping approach indicated that emitted N2O of the slurry applied soil in field appeared to have lower rN2O values and led to more N2O + N2 emissions at the initial fertilization period. The incubation experiment indicated that the N2O emissions of slurry-applied soil were significantly reduced by DCD (â¼45%) and DCD + PC (â¼67%) application in comparison with CK (p < 0.05), and the stronger contributions of bacterial denitrification/nitrifier denitrification to N2O production were revealed by the lower δ15NSP in N2O using the isotopocule mapping approach. In conclusion, in NCP the gaseous losses of the slurry applied field can be largely reduced by using incorporation method, and greater reduction could be achieved given the simultaneous application of nitrification/denitrification inhibitors.
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Gases , Solo , Agricultura/métodos , Animais , Bovinos , Cinnamomum zeylanicum , Fertilizantes/análise , Pradaria , Nitrogênio , Óxido Nitroso/análiseRESUMO
The composting process is important in the recycling of organic wastes produced in agriculture, food, and municipal waste management. This study explored the suitability of using waste vinegar residue (WVR) as an amendment in poultry litter (PL) composting. Four treatments, including poultry litter (CK), poultry litter+vinegar residue (VR), poultry litter+vinegar residue+lime (VR_Ca) and poultry litter+vinegar residue+biochar (VR_B), were conducted. During a 42-day composting period, the dynamics of carbon dioxide (CO2), ammonia (NH3), nitrous oxide (N2O) and methane (CH4) emissions, as well as the physicochemical properties and abundances of the bacteria and fungi of the feedstock were tracked to examine the potential barriers in the co-composting of WVR and PL. Compared to those of the CK, using a WVR amendment lowered the pH, increased the electrical conductivity significantly at the early stage, resulted in a strong inhibition of bacterial and fungal growth and delayed the thermophilic period of poultry litter composting while significantly reducing NH3 and N2O and GHG (CO2-e) emissions. A preadjustment of the WVR with alkaline biochar or lime lengthened the thermophilic period and increased the germination index (GI) by alleviating the inhibitory effect of the WVR on bacterial and fungal growth during composting. However, such preadjustment might reduce the mitigation effect on NH3. In conclusion, WVR can be recycled through co-composting with poultry litter, and the additional mitigation of N losses and N conservation can be achieved without halting compost quality.
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Compostagem , Ácido Acético , Animais , Dióxido de Carbono/análise , Esterco , Metano , Nitrogênio/análise , Óxido Nitroso/análise , Aves Domésticas , Solo/químicaRESUMO
Herein, we disclose a strategy for the asymmetric dearomatization of N-arylacyl indoles via a palladium-catalyzed tandem Heck/carbonylation, leading to an array of indoline-3-carboxylates bearing vicinal C2-aza-quaternary and C3 tertiary stereocenters in high yields and excellent enantio- and diastereoselectivities. This study is an important advance in the field of asymmetric carbonylation and enantioselective dearomatization reactions.
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Indóis , Paládio , Ácidos Carboxílicos , CatáliseRESUMO
COVID-19 infection is a global health issue, and vaccination is the main strategy to control this pandemic. In this study, 189 participants received BNT162b2 or CoronaVac vaccine, and 133 of them recorded adverse events (AEs) daily for 4 weeks after vaccination. Their neutralizing antibody against SARS-CoV-2 was determined with live virus microneutralization (vMN) assay. The vMN geometric mean titer (GMT) on day 56 was 129.9 (95% confidence interval [CI],108.6 to 155.2) in the BNT162b2 group and 13.1 (95% CI, 11.2 to 15.3) in the CoronaVac group. Day 56 vMN GMT was 147.9 (95% CI, 118.9 to 184.1) in females and 129.9 (95% CI, 108.6 to 155.2) in males receiving BNT162b2, while it was 14.0 (95% CI, 11.6 to 17.0) in females and 11.4 (95% CI, 8.7 to 15.0) in males receiving CoronaVac. Injection site pain (88.8%) and redness (77.5%) were the most commonly BNT162b2-related AEs, and injection site pain (37.7%) and tiredness (26.4%) were more frequent in the CoronaVac group. Women showed a higher frequency of headache (45.7% versus 29.4%) and joint pain (26.1 versus 14.7%) than men in BTN162b2 group. Headache (26.5% versus 0%) and tiredness (38.2% versus 5.3%) were more common in women than in men vaccinated with CoronaVac. No correlation between any AE and antibody response was observed in BNT162b2 or CoronaVac platforms. After taking the gender factor into account, in the BNT162b2 group, a low correlation between day 21 vMN titer and redness (rho = 0.34) or itching (rho = 0.32) was presented in females, and a low correlation between day 56 vMN titer and fever (rho = 0.35) was presented in males. Taken together, AEs could have a low correlation with BNT162b2 vaccine response. IMPORTANCE Effective vaccines against SARS-CoV-2 are vital tools for containing the COVID-19 pandemic by increasing population immunity. While currently available vaccines can elicit antibody response against SARS-CoV-2 with high efficacy, the associated side effects may cause vaccine hesitancy. Our work is important in that we have thoroughly analyzed the correlation between immunogenicity and reactogenicity of two COVID-19 vaccines (BNT162b2 and CoronaVac) in the study. Our results showed that women had higher levels of neutralizing antibodies than men after receiving BNT162b2 or CoronaVac. Furthermore, a low correlation was observed between day 21 vMN titer and local reactions (redness and itching) in females, as well as between day 56 vMN titer and fever in males receiving BNT162b2. Thus, common side effects are not always a negative impact of vaccination but may serve as an indicator of immunogenicity of vaccines. Our study may help in increasing the public's acceptance and confidence over COVID-19 vaccination and ultimately achieving the goal of containing COVID-19 pandemic.
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Vacinas contra COVID-19 , COVID-19 , Anticorpos Neutralizantes , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Feminino , Cefaleia , Humanos , Masculino , Dor , Pandemias , Prurido , SARS-CoV-2RESUMO
Detection and tracking of antibodies play an increasingly prominent role in population surveillance and implementation of public health measures to combat the current coronavirus disease 2019 (COVID-19) pandemic, with much attention placed on developing commercial serological assays as point-of-care diagnostic tools. While many rapid diagnostic tests (RDTs) that detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG and IgM antibodies have been evaluated, there is currently limited insight into detection of neutralizing antibodies (nAbs) by such modalities. Here, we evaluate performance characteristics of an RDT that detects SARS-CoV-2 IgG antibodies and, importantly, nAbs based on both infection- and vaccine-immunized cohorts by direct comparison to known antibody titers obtained from live virus microneutralization (VMN) assays. We further contextualize interpretations of band intensity of the RDT with reference to the World Health Organization (WHO) International Standard. We report a sensitivity of 94.37% and specificity of 92.50% for SARS-CoV-2 IgG detection and a sensitivity of 94.37% and specificity of 92.68% for nAbs. A limit of detection was determined as 3.125 IU/mL and 25.00 IU/mL, respectively, with reference to the WHO International Standard. We confirm that indication of nAb concentration, as elucidated by band intensity on the RDT, correlated with nAb titers defined by VMN assays and surrogate nAb assays. We additionally observe no cross-reactivity of the nAb test line to SARS-CoV-1 but report display of weak seropositivity for one sample on the SARS-CoV-2 IgG test line. Our study reveals promising performance characteristics of the assessed RDT, which implicates its usefulness in a wide range of diagnostic and epidemiological settings. IMPORTANCE In the ongoing coronavirus disease 2019 (COVID-19) pandemic, antibody tests play an increasingly important role in detecting previous infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and monitoring of response to vaccinations. In particular, neutralizing antibodies have recently been demonstrated to be highly predictive of immune protection against symptomatic infection. Our study is the first to evaluate a rapid diagnostic test based on samples acquired from both recovered COVID-19 patients and individuals vaccinated for SARS-CoV-2, which detects neutralizing antibodies in addition to SARS-CoV-2 IgG. We report promising sensitivity, specificity, and cross-reactivity profiles, which implicate its usefulness in a wide range of settings as a diagnostic point-of-care tool to aid in curbing transmission and reducing mortality caused by COVID-19 symptoms.
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COVID-19 , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/diagnóstico , Humanos , Imunoglobulina G , Sistemas Automatizados de Assistência Junto ao Leito , Testes ImediatosRESUMO
By vaccinating SARS-CoV-2 naïve individuals who have already received two doses of COVID-19 vaccines, we aimed to investigate whether a heterologous prime-boost strategy, using vaccines of different platforms as the booster dose, can enhance the immune response against SARS-CoV-2 virus variants. Participants were assigned into four groups, each receiving different combination of vaccinations: two doses of BNT162b2 followed by one dose of BNT162b2 booster (B-B-B); Combination of BNT162b2 (first dose) and CoronaVac (second dose) followed by one dose of BNT162b2 booster (B-C-B); two doses of CoronaVac followed by one dose of CoronaVac booster (C-C-C); two doses of CoronaVac followed by one dose of BNT162b2 booster (C-C-B). The neutralizing antibody in sera against the virus was determined with live virus microneutralization assay (vMN). The B-B-B group and C-C-B group demonstrated significantly higher immunogenicity against SARS-CoV-2 Wild type (WT), Beta variant (BV) and Delta variant (DV). In addition, the B-B-B group and C-C-B group showed reduced but existing protection against Omicron variant (OV). Moreover, A persistent rise in vMN titre against OV was observed 3 days after booster dose. Regarding safety, a heterologous prime-boost vaccine strategy is well tolerated. In this study, it was demonstrated that using vaccines of different platforms as booster dose can enhance protection against SARS-CoV-2 variants, offering potent neutralizing activity against wild-type virus (WT), Beta variant (BV), Delta variant (DV) and some protection against the Omicron variant (OV). In addition, a booster mRNA vaccine results in a more potent immune response than inactivated vaccine regardless of which platform was used for prime doses.
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The emergence of SARS-CoV-2 variants may impact the effectiveness of vaccines, while heterologous vaccine strategy is considered to provide better protection. The immunogenicity of an mRNA-inactivated virus vaccine against the SARS-CoV-2 wild-type (WT) and variants was evaluated in the study. SARS-CoV-2 naïve adults (n = 123) were recruited and placed in the following groups: BNT162b2, CoronaVac or BNT162b2-CoronaVac (Combo) Group. Blood samples were collected to measure neutralization antibodies (NAb) by a live virus microneutralization assay (vMN) and surrogate NAb test. The day 56 vMN geometric mean titre (GMT) was 26.2 [95% confident interval (CI), [22.3-30.9] for Combo, 136.9 (95% CI, 104.2-179.7) for BNT162b2, and 14.7 (95% CI, 11.6-18.6) for CoronaVac groups. At 6 months post-first dose, the GMT declined to 8.0, 28.8 and 7.1 in the Combo, BNT162b2 and CoronaVac groups, respectively. Three groups showed reduced neutralizing activity against D614G, beta, theta and delta variants. At day 56 GMT (74.6) and month 6 GMT (22.7), the delta variant in the BNT162b2 group was higher than that in the Combo (day 56, 7.4; month 6, 5.5) and CoronaVac groups (day 56, 8.0; month 6, 5) (p < 0.0001). Furthermore, the mean surrogate NAb value on day 56 in the BNT162b2 group was 594.7 AU/mL and higher than 40.5 AU/mL in Combo and 38.8 AU/mL in CoronaVac groups (p < 0.0001). None of the participants developed severe adverse events, and all other adverse events were self-limiting. The Combo vaccination strategy was safe. The overall vaccine immunogenicity at day 56 and 6 months were comparable to the homologous CoronaVac group but inferior to the homologous BNT162b2 group, against both the WT and all variants. Furthermore, the antibody response of vaccines waned at 6 months and thereby, a third dose of the vaccine is needed for these vaccines.
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Immunofluorescence is a traditional diagnostic method for respiratory viruses, allowing rapid, simple and accurate diagnosis, with specific benefits of direct visualization of antigens-of-interest and quality assessment. This study aims to evaluate the potential of indirect immunofluorescence as an in-house diagnostic method for SARS-CoV-2 antigens from nasopharyngeal swabs (NPS). Three primary antibodies raised from mice were used for immunofluorescence staining, including monoclonal antibody against SARS-CoV nucleocapsid protein, and polyclonal antibodies against SARS-CoV-2 nucleocapsid protein and receptor-binding domain of SARS-CoV-2 spike protein. Smears of cells from NPS of 29 COVID-19 patients and 20 non-infected individuals, and cells from viral culture were stained by the three antibodies. Immunofluorescence microscopy was used to identify respiratory epithelial cells with positive signals. Polyclonal antibody against SARS-CoV-2 N protein had the highest sensitivity and specificity among the three antibodies tested, detecting 17 out of 29 RT-PCR-confirmed COVID-19 cases and demonstrating no cross-reactivity with other tested viruses except SARS-CoV. Detection of virus-infected cells targeting SARS-CoV-2 N protein allow identification of infected individuals, although accuracy is limited by sample quality and number of respiratory epithelial cells. The potential of immunofluorescence as a simple diagnostic method was demonstrated, which could be applied by incorporating antibodies targeting SARS-CoV-2 into multiplex immunofluorescence panels used clinically, such as for respiratory viruses, thus allowing additional routine testing for diagnosis and surveillance of SARS-CoV-2 even after the epidemic has ended with low prevalence of COVID-19.
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Vaccinating recovered patients previously infected by COVID-19 with mRNA vaccines to boost their immune response against wild-type viruses (WT), we aimed to investigate whether vaccine platform and time of vaccination affect immunogenicity against the SARS-CoV-2 WT and Delta variant (DV). Convalescent patients infected by COVID-19 were recruited and received one booster dose of the BNT162b2 (PC-B) or CoronaVac (PC-C) vaccines, while SARS-CoV-2 naïve subjects received two doses of the BNT162b2 (CN-B) or CoronaVac (CN-C) vaccines. The neutralizing antibody in sera against the WT and DV was determined with live virus neutralization assay (vMN). The vMN geometric mean titre (GMT) against WT in recovered individuals previously infected by COVID-19 reduced significantly from 60.0 (95% confidence interval (CI), 46.5-77.4) to 33.9 (95% CI, 26.3-43.7) at 6 months post recovery. In the PC-B group, the BNT162b2 vaccine enhanced antibody response against WT and DV, with 22.3-fold and 20.4-fold increases, respectively. The PC-C group also showed 1.8-fold and 2.2-fold increases for WT and DV, respectively, after receiving the CoronaVac vaccine. There was a 10.6-fold increase in GMT in the CN-B group and a 1.3-fold increase in the CN-C group against DV after full vaccination. In both the PC-B and PC-C groups, there was no difference between GMT against WT and DV after vaccination. Subjects in the CN-B and CN-C groups showed inferior GMT against DV compared with GMT against WT after vaccination. In this study, one booster shot effectively enhanced the pre-existing neutralizing activity against WT and DV in recovered subjects.
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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-neutralizing antibody (NAb) production is a crucial humoral response that can reduce re-infection or breakthrough infection. The conventional test used to measure NAb production capacity levels is the live virus-neutralizing assay. However, this test must be conducted under biosafety level-3 containment. Pseudovirus or surrogate NAb tests, such as angiotensin-converting enzyme 2 inhibition tests, can be performed under level-2 containment. The aim of this study was to evaluate the performance of a surrogate SARS-CoV-2 NAb assay (sNAb) using samples from naturally infected individuals and vaccine recipients in comparison with the live virus microneutralization assay (vMN). Three hundred and eighty serum samples which were collected from 197 patients with COVID-19, 96 vaccine recipients and 84 normal individuals were analyzed. Overall, the sensitivity, specificity, positive predictive value, and negative predictive value of the sNAb (iFlash-2019-NAb assay, Shenzhen, China) were 97.9%, 94.9%, 98.2%, and 93.8%, respectively. Agreement for the assay relative to vMN for naturally infected individuals and vaccine recipients were 98.5% and 93.9%, respectively. A correlation analysis between sNAb and the vMN for both of these groups yielded an R2 value of 0.83. The iFlash RBD NAb assay is found to be sensitive and reliable for neutralizing antibody measurement in patients with the 2019 coronavirus disease and those who have been vaccinated against it.
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This systematic review and meta-analysis was conducted to compare the safety and efficacy of 2019 novel coronavirus disease (COVID-19) vaccines according to vaccine platform and severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infection severity. Articles published between 24 January 2020 and 30 May 2021 were retrieved via a PubMed and EMBASE search. A total of 12 reports on phase-3 clinical trials and observational studies of COVID-19 vaccines were included in the review. In terms of vaccine safety, mRNA vaccines showed more relevance to serious adverse events than viral vector and inactivated vaccines, but no solid evidence indicated that COVID-19 vaccines directly caused serious adverse events. Serious metabolic, musculoskeletal, immune-system, and renal disorders were more common among inactivated vaccine recipients, and serious gastrointestinal complications and infections were more common among viral vector and inactivated vaccine recipients. The occurrence of serious vessel disorders was more frequent in mRNA vaccines. In terms of efficacy, two mRNA vaccine doses conferred a lesser risk of SARS-COV-2 infection (odds ratio: 0.05; 95% confidence interval: 0.02-0.13) than did vaccination with viral vector and inactivated vaccines. All vaccines protected more against symptomatic than asymptomatic cases (risk ratio, 0.11 vs. 0.34), but reduced the risk of severe SARS-COV-2 infection. The COVID-19 vaccines assessed in this study are sufficiently safe and effective. The results indicate that two mRNA vaccine doses prevent SARS-COV-2 infection most effectively, but further research is needed due to the high degree of heterogeneity among studies in this sample. Interventions should be implemented continuously to reduce the risks of infection after one vaccine dose and asymptomatic infection.
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Liver cirrhosis is one major cause of mortality in the clinic, and treatment of this disease is an arduous task. The scenario will be even getting worse with increasing alcohol consumption and obesity in the current lifestyle. To date, we have no medicines to cure cirrhosis. Although many etiologies are associated with cirrhosis, abnormal intestinal microbe flora (termed dysbiosis) is a common feature in cirrhosis regardless of the causes. Toll-like receptors (TLRs), one evolutional conserved family of pattern recognition receptors in the innate immune systems, play a central role in maintaining the homeostasis of intestinal microbiota and inducing immune responses by recognizing both commensal and pathogenic microbes. Remarkably, recent studies found that correction of intestinal flora imbalance could change the progress of liver cirrhosis. Therefore, correction of intestinal dysbiosis and targeting TLRs can provide novel and promising strategies in the treatment of liver cirrhosis. Here we summarize the recent advances in the related topics. Investigating the relationship among innate immunity TLRs, intestinal flora disorders, and liver cirrhosis and exploring the underlying regulatory mechanisms will assuredly have a bright future for both basic and clinical research.