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1.
Psychol Health Med ; : 1-11, 2022 Sep 27.
Article in English | MEDLINE | ID: covidwho-20245270

ABSTRACT

This study aimed to evaluate the influence of COVID-19 on the mental health of Chinese medical students at 1-year of follow-up. From 2 February 2020 to 23 February 2021, we conducted three waves of research online (T1 = during outbreak, T2 = controlling period, T3 = 1 year after outbreak). The survey collected demographic data and several self reporting questionnaires to measure the depressive, anxiety and stress symptoms. A total of 4002 participants complete the whole research phases. The study major, grade level and gender were the main factors related to psychological distress caused by the COVID-19 crisis. Importantly, medical knowledge has a protective effect on medical students' psychological distress during the COVID-19 period.

2.
Vaccines (Basel) ; 11(5)2023 May 09.
Article in English | MEDLINE | ID: covidwho-20238604

ABSTRACT

(1) Background: As the COVID-19 pandemic enters its fourth year, it continues to cause significant morbidity and mortality worldwide. Although various vaccines have been approved and the use of homologous or heterologous boost doses is widely promoted, the impact of vaccine antigen basis, forms, dosages, and administration routes on the duration and spectrum of vaccine-induced immunity against variants remains incompletely understood. (2) Methods: In this study, we investigated the effects of combining a full-length spike mRNA vaccine with a recombinant S1 protein vaccine, using intradermal/intramuscular, homologous/heterologous, and high/low dosage immunization strategies. (3) Results: Over a period of seven months, vaccination with a mutant recombinant S1 protein vaccine based on the full-length spike mRNA vaccine maintained a broadly stable humoral immunity against the wild-type strain, a partially attenuated but broader-spectrum immunity against variant strains, and a comparable level of cellular immunity across all tested strains. Furthermore, intradermal vaccination enhanced the heterologous boosting of the protein vaccine based on the mRNA vaccine. (4) Conclusions: This study provides valuable insights into optimizing vaccination strategies to address the ongoing challenges posed by emerging SARS-CoV-2 variants.

3.
Virol Sin ; 38(3): 344-350, 2023 Jun.
Article in English | MEDLINE | ID: covidwho-2311861

ABSTRACT

The current pandemic of COVID-19 caused by a novel coronavirus, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), threatens human health around the world. Of particular concern is that bats are recognized as one of the most potential natural hosts of SARS-CoV-2; however, coronavirus ecology in bats is still nascent. Here, we performed a degenerate primer screening and next-generation sequencing analysis of 112 bats, collected from Hainan Province, China. Three coronaviruses, namely bat betacoronavirus (Bat CoV) CD35, Bat CoV CD36 and bat alphacoronavirus CD30 were identified. Bat CoV CD35 genome had 99.5% identity with Bat CoV CD36, both sharing the highest nucleotide identity with Bat Hp-betacoronavirus Zhejiang2013 (71.4%), followed by SARS-CoV-2 (54.0%). Phylogenetic analysis indicated that Bat CoV CD35 formed a distinct clade, and together with Bat Hp-betacoronavirus Zhejiang2013, was basal to the lineage of SARS-CoV-1 and SARS-CoV-2. Notably, Bat CoV CD35 harbored a canonical furin-like S1/S2 cleavage site that resembles the corresponding sites of SARS-CoV-2. The furin cleavage sites between CD35 and CD36 are identical. In addition, the receptor-binding domain of Bat CoV CD35 showed a highly similar structure to that of SARS-CoV-1 and SARS-CoV-2, especially in one binding loop. In conclusion, this study deepens our understanding of the diversity of coronaviruses and provides clues about the natural origin of the furin cleavage site of SARS-CoV-2.


Subject(s)
COVID-19 , Chiroptera , Animals , Humans , SARS-CoV-2/genetics , SARS-CoV-2/metabolism , Phylogeny , Furin/genetics , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism
4.
Front Psychiatry ; 12: 652296, 2021.
Article in English | MEDLINE | ID: covidwho-2268656

ABSTRACT

Coronavirus disease 2019 (COVID-19) has significantly caused socioeconomic impacts. However, little is known about the psychological effect of COVID-19 on home-quarantined nursing students. The present study aimed to identify the prevalence and major determinants of anxiety, depression and post-traumatic stress symptoms (PTSS) in Chinese nursing students during the COVID-19 pandemic quarantine period. An online survey was conducted on a sample of 6,348 home-quarantined nursing students. Mental health status was assessed by the Generalized Anxiety Disorder 7-Item Scale (GAD-7), the Patient Health Questionnaire 9-Item Scale (PHQ-9) and the Post Traumatic Stress Disorder Check List-Civilian version (PCL-C), respectively. Logistic regression analyses were performed to identify risk factors of anxiety, depression and PTSS. The overall prevalence of anxiety was 34.97%, and the rates of "mild," "moderate," and "severe" anxiety were 26.24, 7.04, and 1.69%, respectively. Depression was detected in 40.22% of the nursing students, and the prevalence of "mild," "moderate," "moderately severe," and "severe" depression was 27.87, 7.18, 4.08, and 1.09%, respectively. The overall prevalence of PTSS was 14.97%, with the prevalence of "mild" and "moderate-to-severe" PTSS reported at 7.04 and 7.93%, respectively. Male gender and insufficient social support were common risk factors for anxiety, depression and PTSS. In conclusion, about one-third, two-fifths, and one-seventh of Chinese nursing students had anxiety, depression and PTSS during the period of home quarantine, respectively. Timely and appropriate psychological interventions for nursing students should be implemented to reduce the psychological harm caused by COVID-19 pandemic.

5.
Vaccines (Basel) ; 11(3)2023 Feb 23.
Article in English | MEDLINE | ID: covidwho-2288126

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike (S) protein is a critical viral antigenic protein that enables the production of neutralizing antibodies, while other structural proteins, including the membrane (M), nucleocapsid (N) and envelope (E) proteins, have unclear roles in antiviral immunity. In this study, S1, S2, M, N and E proteins were expressed in 16HBE cells to explore the characteristics of the resultant innate immune response. Furthermore, peripheral blood mononuclear cells (PBMCs) from mice immunized with two doses of inactivated SARS-CoV-2 vaccine or two doses of mRNA vaccine were isolated and stimulated by these five proteins to evaluate the corresponding specific T-cell immune response. In addition, the levels of humoral immunity induced by two-dose inactivated vaccine priming followed by mRNA vaccine boosting, two homologous inactivated vaccine doses and two homologous mRNA vaccine doses in immunized mice were compared. Our results suggested that viral structural proteins can activate the innate immune response and elicit a specific T-cell response in mice immunized with the inactivated vaccine. However, the existence of the specific T-cell response against M, N and E is seemingly insufficient to improve the level of humoral immunity.

6.
Biosens Bioelectron ; 217: 114739, 2022 Dec 01.
Article in English | MEDLINE | ID: covidwho-2271903

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic has created a huge demand for sensitive and rapid detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The current gold standard for SARS-CoV-2 detection is reverse transcription-polymerase chain reaction (RT-PCR)-based nucleic acid amplification. However, RT-PCR is time consuming and requires specialists and large instruments that are unattainable for point-of-care testing (POCT). To develop POCT for SARS-CoV-2, we combined recombinase polymerase amplification (RPA) and FeS2 nanozyme strips to achieve facile nucleic acid amplification and subsequent colorimetric signal enhancement based on the high peroxidase-like activity of the FeS2 nanozymes. This method showed a nucleic acid limit of detection (LOD) for SARS-CoV-2 of 200 copies/mL, close to that of RT-PCR. The unique catalytic properties of the FeS2 nanozymes enabled the nanozyme-strip to amplify colorimetric signals via the nontoxic 3,3',5,5'-tetramethylbenzidine (TMB) substrate. Importantly, the detection of clinical samples of human papilloma virus type 16 (HPV-16) showed 100% agreement with previous RT-PCR results, highlighting the versatility and reliability of this method. Our findings suggest that nanozyme-based nucleic acid detection has great potential in the development of POCT diagnosis for COVID-19 and other viral infections.


Subject(s)
Biosensing Techniques , COVID-19 , Nucleic Acids , COVID-19/diagnosis , Humans , Nucleic Acid Amplification Techniques/methods , Peroxidases , RNA, Viral/analysis , RNA, Viral/genetics , Recombinases , Reproducibility of Results , SARS-CoV-2/genetics , Sensitivity and Specificity
7.
Chinese Journal of Endemiology ; 40(5):419-425, 2021.
Article in Chinese | GIM | ID: covidwho-2163761

ABSTRACT

Objective: This article analyzes the epidemic situation and characteristics of Corona virus disease 2019 (COVID-19) in Russian Federation (referred to as Russia). summarizes the effective measures and problems exposed by Russia to deal with COVID-19, so as to provide reference for our country's epidemic prevention and control, and seek the direction of cooperation under the background of Sino Russia scientific and technological innovation in view of public health emergency.

8.
Vaccines (Basel) ; 10(12)2022 Nov 24.
Article in English | MEDLINE | ID: covidwho-2123909

ABSTRACT

The novel coronavirus (SARS-CoV-2) epidemic continues to be a global public crisis affecting human health. Many research groups are developing different types of vaccines to suppress the spread of SARS-CoV-2, and some vaccines have entered phase III clinical trials and have been rapidly implemented. Whether multiple antigen matches are necessary to induce a better immune response remains unclear. To address this question, this study tested the immunogenicity and protective effects of a SARS-CoV-2 recombinant S and N peptide vaccine in the Syrian golden hamster model. This experiment was based on two immunization methods: intradermal and intramuscular administration. Immunized hamsters were challenged with live SARS-CoV-2 14 days after booster immunization. Clinical symptoms were observed daily, and the antibody titer and viral load in each tissue were detected. The results showed that immunization of golden hamsters with the SARS-CoV-2 structural protein S alone or in combination with the N protein through different routes induced antibody responses, whereas immunization with the N protein alone did not. However, although the immunized hamsters exhibited partial alleviation of clinical symptoms when challenged with the virus, neither vaccine effectively inhibited the proliferation and replication of the challenging virus. In addition, the pathological damage in the immunized hamsters was similar to that in the control hamsters. Interestingly, the neutralizing antibody levels of all groups including immunized and nonimmunized animals increased significantly after viral challenge. In conclusion, the immune response induced by the experimental S and N polypeptide vaccines had no significant ability to prevent viral infection and pathogenicity in golden hamsters.

9.
Front Immunol ; 13: 956369, 2022.
Article in English | MEDLINE | ID: covidwho-2022739

ABSTRACT

Background: Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused significant loss of life and property. In response to the serious pandemic, recently developed vaccines against SARS-CoV-2 have been administrated to the public. Nevertheless, the research on human immunization response against COVID-19 vaccines is insufficient. Although much information associated with vaccine efficacy, safety and immunogenicity has been reported by pharmaceutical companies based on laboratory studies and clinical trials, vaccine evaluation needs to be extended further to better understand the effect of COVID-19 vaccines on human beings. Methods: We performed a comparative peptidome analysis on serum samples from 95 participants collected at four time points before and after receiving CoronaVac. The collected serum samples were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to profile the serum peptides, and also subjected to humoral and cellular immune response analyses to obtain typical immunogenicity information. Results: Significant difference in serum peptidome profiles by MALDI-TOF MS was observed after vaccination. By supervised statistical analysis, a total of 13 serum MALDI-TOF MS feature peaks were obtained on day 28 and day 42 of vaccination. The feature peaks were identified as component C1q receptor, CD59 glycoprotein, mannose-binding protein C, platelet basic protein, CD99 antigen, Leucine-rich alpha-2-glycoprotein, integral membrane protein 2B, platelet factor 4 and hemoglobin subunits. Combining with immunogenicity analysis, the study provided evidence for the humoral and cellular immune responses activated by CoronaVac. Furthermore, we found that it is possible to distinguish neutralizing antibody (NAbs)-positive from NAbs-negative individuals after complete vaccination using the serum peptidome profiles by MALDI-TOF MS together with machine learning methods, including random forest (RF), partial least squares-discriminant analysis (PLS-DA), linear support vector machine (SVM) and logistic regression (LR). Conclusions: The study shows the promise of MALDI-TOF MS-based serum peptidome analysis for the assessment of immune responses activated by COVID-19 vaccination, and discovered a panel of serum peptides biomarkers for COVID-19 vaccination and for NAbs generation. The method developed in this study can help not only in the development of new vaccines, but also in the post-marketing evaluation of developed vaccines.


Subject(s)
COVID-19 Vaccines , COVID-19 , Antibodies, Neutralizing , Biomarkers , COVID-19/prevention & control , Glycoproteins , Humans , Immunity , Peptides/chemistry , SARS-CoV-2
10.
Adv Compos Hybrid Mater ; 5(2): 1221-1232, 2022.
Article in English | MEDLINE | ID: covidwho-1943800

ABSTRACT

The worldwide pandemic, coronavirus COVID-19, has been posing a serious threat to the global economy and security in last 2 years. The monthly consumption and subsequent discarding of 129 billion masks (equivalent to 645,000 tons) pose a serious detrimental impact on environmental sustainability. In this study, we report a novel type of nanofibrous membranes (NFMs) with supreme filtration performance and controllable degradation rates, which are mainly composed of polylactic acid (PLA) and artificially cultured diatom frustules (DFs). In this way, the filtration efficiency of particular matter (PM) and the pressure drop were significantly improved in the prepared PLA/DFs NFMs as compared with the neat PLA NFM. In specific, with incorporation of 5% DFs into fibers, PM0.3 removal with a filtration efficiency of over 99% and a pressure drop of 109 Pa were achieved with a membrane thickness of only 0.1 mm. Moreover, the yield strength and crystallinity degree of the PLA/DFs5 NFMs were sharply increased from 1.88 Mpa and 26.37% to 2.72 Mpa and 30.02%. Besides those unique characters, the PLA/DFs5 presented excellent degradability, accompanied by the degradation of 38% in 0.01 M sodium hydroxide solution after 7 days and approximately 100% in natural condition after 42 days, respectively. Meanwhile, the environmentally friendly raw materials of the composite polylactic acid and artificially cultured diatom frustules could be extracted from corn-derived biomass and artificially cultivated diatoms, ensuring the conformance to carbon neutrality and promising applications in personal protection. Supplementary information: The online version contains supplementary material available at 10.1007/s42114-022-00474-7.

11.
Vaccines (Basel) ; 10(6)2022 Jun 10.
Article in English | MEDLINE | ID: covidwho-1911679

ABSTRACT

OBJECTIVE: We constructed two DNA vaccines containing the receptor-binding domain (RBD) genes of multiple SARS-CoV-2 variants and used them in combination with inactivated vaccines in a variety of different protocols to explore potential novel immunization strategies against SARS-CoV-2 variants. METHODS: Two DNA vaccine candidates with different signal peptides (namely, secreted and membrane signal peptides) and RBD protein genes of different SARS-CoV-2 strains (Wuhan-Hu-1, B.1.351, B.1.617.2, C.37) were used. Four different combinations of DNA and inactivated vaccines were tested, namely, Group A: three doses of DNA vaccine; B: three doses of DNA vaccine and one dose of inactivated vaccine; C: two doses of inactivated vaccine and one dose of DNA vaccine; and D: coadministration of DNA and inactivated vaccines in two doses. Subgroups were grouped according to the signal peptide used (subgroup 1 contained secreted signal peptides, and subgroup 2 contained membrane signal peptides). The in vitro expression of the DNA vaccines, the humoral and cellular immunity responses of the immunized mice, the immune cell population changes in local lymph nodes, and proinflammatory cytokine levels in serum samples were evaluated. RESULTS: The antibody responses and cellular immunity in Group A were weak for all SARS-CoV-2 strains; for Group B, there was a great enhancement of neutralizing antibody (Nab) titers against the B.1.617.2 variant strain. Group C showed a significant increase in antibody responses (NAb titers against the Wuhan-Hu-1 strain were 768 and 1154 for Group C1 and Group C2, respectively, versus 576) and cellular immune responses, especially for variant B.1.617.2 (3240 (p < 0.001) and 2430 (p < 0.05) for Group C1 and Group C2, versus 450); Group D showed an improvement in immunogenicity. Group C induced higher levels of multiple cytokines. CONCLUSION: The DNA vaccine candidates we constructed, administered as boosters, could enhance the humoral and cellular immune responses of inactivated vaccines against COVID-19, especially for B.1.617.2.

13.
Int J Environ Res Public Health ; 19(7)2022 03 23.
Article in English | MEDLINE | ID: covidwho-1785624

ABSTRACT

The risks faced by the mining industry have always been prominent for every walk of life in China. As the direct cause of accidents, individual unsafe behaviors are closely related to their risk perception. So, it is important to explore the factors affecting miners' risk perception and analyze the influencing mechanisms between these factors and risk perception. The questionnaire survey method was used to collect the data of risk perception from nearly 400 respondents working in metal mines in China. Exploratory factor analysis and confirmatory factor analysis were used to analyze and process collected data. The impact of four factors affecting miners' risk perception was verified, namely: organizational safety atmosphere, organizational trust, knowledge level, and risk communication. Then, regression analysis, Pearson correlation analysis, and structural equation model analysis were used to examine the effect of the four influencing factors on miners' risk perception. The four influencing factors all have a positive impact on miners' risk perception; knowledge level has the largest explained variation of miners' risk perception, followed by risk communication. Organizational trust and organizational safety atmosphere have an indirect and positive impact on miners' risk perception intermediated by knowledge level and risk communication. The results offer four important aspects of mine safety management to help miners establish quick and accurate risk perception, thereby reducing unsafe behaviors and avoiding accidents.


Subject(s)
Miners , China , Humans , Mining , Perception , Safety Management
14.
Medicine (Baltimore) ; 101(7): e28880, 2022 Feb 18.
Article in English | MEDLINE | ID: covidwho-1774439

ABSTRACT

BACKGROUND: There is still a lack of large-scale clinical studies and evidence-based evidence to prove the relationship between serum amyloid A (SAA) and the severity and prognosis of patients with new coronavirus pneumonia (COVID-19). METHODS: We searched PubMed, Cochrane Library, Excerpta Medica Database, and Web of Science for original articles from December 1, 2019 to December 19, 2020. Search criteria include free text search, explosive MESH/EMTREE terms, and all synonyms for SAA and COVID-19. There are no language restrictions on the searched documents. Statistical methods were performed using Stata 14.0 software, and RevMan 5.4 software provided by the Cochrane Collaboration for meta-analysis. The 10 included studies in the literature were classified according to the severity of the novel coronavirus treatment guidelines, with mild/moderate categorized as nonsevere and severe/critical as severe, and the data were meta-analyzed using multiple subgroup standard deviations combined. Severe and nonsevere were finally divided into 2 groups, and the combined data were meta-analyzed according to the standardized mean difference. RESULTS: The results of the meta-analysis given by random effects showed that SAA levels were significantly higher in severe vs nonsevere (standardized mean difference 1.20 [95% confidence interval 0.91-1.48]), which was statistically significant (P < .001). The 3 literatures studied (random effect size 0.11 [95% confidence interval 0.05-0.19]; I2 = 56.68%) and were statistically significant, z = 5.46 P < .01, suggesting that the risk of death occurs at higher levels with increasing SAA values, with the risk of death in the severe group being 11% higher than in the nonsevere group. CONCLUSION: SAA can be considered as a biomarker for predicting the severity and prognosis of COVID-19. SAA can be used for early warning of the poor prognosis of COVID-19 and for monitoring the recovery process, which has important clinical value.


Subject(s)
COVID-19 , Serum Amyloid A Protein , Humans , Prognosis
15.
Emerg Microbes Infect ; 11(1): 212-226, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1585243

ABSTRACT

The recent emergence of COVID-19 variants has necessitated the development of new vaccines that stimulate the formation of high levels of neutralizing antibodies against S antigen variants. A new strategy involves the intradermal administration of heterologous vaccines composed of one or two doses of inactivated vaccine and a booster dose with the mutated S1 protein (K-S). Such vaccines improve the immune efficacy by increasing the neutralizing antibody titers and promoting specific T cell responses against five variants of the RBD protein. A viral challenge test with the B.1.617.2 (Delta) variant confirmed that both administration schedules (i.e. "1 + 1" and "2 + 1") ensured protection against this strain. These results suggest that the aforementioned strategy is effective for protecting against new variants and enhances the anamnestic immune response in the immunized population.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/immunology , Immunity , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , CHO Cells , COVID-19/virology , COVID-19 Vaccines/administration & dosage , Chlorocebus aethiops , Cricetulus , Female , Humans , Macaca mulatta , Mice , Mice, Transgenic , Vaccination , Vaccines, Inactivated/administration & dosage , Vaccines, Inactivated/immunology , Vero Cells
16.
Clin Infect Dis ; 73(11): e3949-e3955, 2021 12 06.
Article in English | MEDLINE | ID: covidwho-1561940

ABSTRACT

BACKGROUND: We evaluated an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine for immunogenicity and safety in adults aged 18-59 years. METHODS: In this randomized, double-blinded, controlled trial, healthy adults received a medium dose (MD) or a high dose (HD) of the vaccine at an interval of either 14 days or 28 days. Neutralizing antibody (NAb) and anti-S and anti-N antibodies were detected at different times, and adverse reactions were monitored for 28 days after full immunization. RESULTS: A total of 742 adults were enrolled in the immunogenicity and safety analysis. Among subjects in the 0, 14 procedure, the seroconversion rates of NAb in MD and HD groups were 89% and 96% with geometric mean titers (GMTs) of 23 and 30, respectively, at day 14 and 92% and 96% with GMTs of 19 and 21, respectively, at day 28 after immunization. Anti-S antibodies had GMTs of 1883 and 2370 in the MD group and 2295 and 2432 in the HD group. Anti-N antibodies had GMTs of 387 and 434 in the MD group and 342 and 380 in the HD group. Among subjects in the 0, 28 procedure, seroconversion rates for NAb at both doses were both 95% with GMTs of 19 at day 28 after immunization. Anti-S antibodies had GMTs of 937 and 929 for the MD and HD groups, and anti-N antibodies had GMTs of 570 and 494 for the MD and HD groups, respectively. No serious adverse events were observed during the study period. CONCLUSIONS: Adults vaccinated with inactivated SARS-CoV-2 vaccine had NAb as well as anti-S/N antibody and had a low rate of adverse reactions. CLINICAL TRIALS REGISTRATION: NCT04412538.


Subject(s)
COVID-19 , SARS-CoV-2 , Adult , Antibodies, Neutralizing , Antibodies, Viral , COVID-19 Vaccines , Double-Blind Method , Humans , Immunogenicity, Vaccine
17.
Emerg Microbes Infect ; 10(1): 2194-2198, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1504286

ABSTRACT

Inactivated coronaviruses, including severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1) and Middle East respiratory syndrome coronavirus (MERS-CoV), as potential vaccines have been reported to result in enhanced respiratory diseases (ERDs) in murine and nonhuman primate (NHP) pneumonia models after virus challenge, which poses great safety concerns of antibody-dependent enhancement (ADE) for the rapid wide application of inactivated SARS-CoV-2 vaccines in humans, especially when the neutralizing antibody levels induced by vaccination or initial infection quickly wane to nonneutralizing or subneutralizing levels over the time. With passive transfer of diluted postvaccination polyclonal antibodies to mimic the waning antibody responses after vaccination, we found that in the absence of cellular immunity, passive infusion of subneutralizing or nonneutralizing anti-SARS-CoV-2 antibodies could still provide some level of protection against infection upon challenge, and no low-level antibody-enhanced infection was observed. The anti-SARS-CoV-2 IgG-infused group and control group showed similar, mild to moderate pulmonary immunopathology during the acute phase of virus infection, and no evidence of vaccine-related pulmonary immunopathology enhancement was found. Typical immunopathology included elevated MCP-1, IL-8 and IL-33 in bronchoalveolar lavage fluid; alveolar epithelial hyperplasia; and exfoliated cells and mucus in bronchioles. Our results corresponded with the recent observations that no pulmonary immunology was detected in preclinical studies of inactivated SARS-CoV-2 vaccines in either murine or NHP pneumonia models or in large clinical trials and further supported the safety of inactivated SARS-CoV-2 vaccines.


Subject(s)
Antibodies, Viral/immunology , Antibody-Dependent Enhancement , COVID-19 Vaccines/immunology , COVID-19/immunology , Immunogenicity, Vaccine , SARS-CoV-2/immunology , Alveolar Epithelial Cells/pathology , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/toxicity , Bronchioles/chemistry , Bronchioles/pathology , Bronchoalveolar Lavage Fluid/chemistry , Bronchoalveolar Lavage Fluid/immunology , COVID-19/pathology , COVID-19/virology , Cytokines/analysis , Humans , Hyperplasia , Immunoglobulin G/immunology , Immunoglobulin G/toxicity , Lung/pathology , Macaca mulatta , Male , Mice , Mucus , SARS-CoV-2/isolation & purification , SARS-CoV-2/physiology , Vaccines, Inactivated/immunology
18.
Vaccine ; 39(48): 6980-6983, 2021 11 26.
Article in English | MEDLINE | ID: covidwho-1475113

ABSTRACT

In clinical trials, antibodies against SARS-CoV-2 were almost eliminated in participants six months after immunization with an inactivated SARS-CoV-2 vaccine. The short duration of antibody persistence is an urgent problem. In this study, the problem was solved by intradermal inoculation with trace antigen. Within 72 h after intradermal inoculation, slight inflammatory reactions, such as redness and swelling, were observed at the inoculation site of the participants. On the 7th, 60th and 180th days after inoculation, the antibodies of the participants were detected, and it was found that the neutralizing antibody and ELISA (IgGs) anti-S antibody levels rapidly increased and were maintained for 6 months. These results indicate that there was a SARS-CoV-2-specific immune response in the participants immunized with an inactivated SARS-CoV-2 vaccine, which could be quickly and massively activated by intradermal trace antigen inoculation to produce an effective clinically protective effect.


Subject(s)
COVID-19 Vaccines , COVID-19 , Antibodies, Neutralizing , Antibodies, Viral , Humans , SARS-CoV-2
19.
Stem Cells Int ; 2021: 9974635, 2021.
Article in English | MEDLINE | ID: covidwho-1440852

ABSTRACT

There is a population of p63+/Krt5+ distal airway stem cells (DASCs) quiescently located in the airway basal epithelium of mammals, responding to injury and airway epithelial regeneration. They hold the ability to differentiate into multiple pulmonary cell types and can repopulate the epithelium after damage. The current study aims at gaining further insights into the behavior and characteristics of the DASCs isolated from the patient lung and exploring their clinical translational potential. Human DASCs were brushed off through the bronchoscopic procedure and expanded under the pharmaceutical-grade condition. Their phenotype stability in long-term cell culture was analyzed, followed by safety evaluation and tumorigenic analysis using multiple animal models including rodents and nonhuman primate. The chimerism of the human-mouse lung model indicated that DASC pedigrees could give rise to multiple epithelial types, including type I alveolar cells as well as bronchiolar secretory cells, to regenerate the distal lung. Taken together, the results suggested that DASC transplantation could be a promising therapeutic approach for unmet needs in respiratory medicine including the COVID-19-related diseases.

20.
Mol Ther Methods Clin Dev ; 23: 108-118, 2021 Dec 10.
Article in English | MEDLINE | ID: covidwho-1379195

ABSTRACT

Because of the relatively limited understanding of coronavirus disease 2019 (COVID-19) pathogenesis, immunological analysis for vaccine development is needed. Mice and macaques were immunized with an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine prepared by two inactivators. Various immunological indexes were tested, and viral challenges were performed on day 7 or 150 after booster immunization in monkeys. This inactivated SARS-CoV-2 vaccine was produced by sequential inactivation with formaldehyde followed by propiolactone. The various antibody responses and specific T cell responses to different viral antigens elicited in immunized animals were maintained for longer than 150 days. This comprehensive immune response could effectively protect vaccinated macaques by inhibiting viral replication in macaques and substantially alleviating immunopathological damage, and no clinical manifestation of immunopathogenicity was observed in immunized individuals during viral challenge. This candidate inactivated vaccine was identified as being effective against SARS-CoV-2 challenge in rhesus macaques.

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