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2.
Preprint in English | medRxiv | ID: ppmedrxiv-22279589

ABSTRACT

BACKGROUNDThe rising breakthrough infections caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, especially Omicron and its sub-lineages, have raised an urgent need to develop broad-spectrum vaccines against coronavirus disease 2019 (COVID-19). We have developed a mosaic-type recombinant vaccine candidate, named NVSI-06-09, having immune potentials against a broad range of SARS-CoV-2 variants. METHODSAn ongoing randomized, double-blind, controlled phase 2 trial was conducted to evaluate the safety and immunogenicity of NVSI-06-09 as a booster dose in subjects aged 18 years and older from the United Arab Emirates (UAE), who had completed two or three doses of BBIBP-CorV vaccinations at least 6 months prior to the enrollment. The participants were randomly assigned with 1:1 to receive a booster dose of NVSI-06-09 or BBIBP-CorV. The primary outcomes were immunogenicity and safety against SARS-CoV-2 Omicron variant, and the exploratory outcome was cross-immunogenicity against other circulating strains. RESULTSA total of 516 participants received booster vaccination. Interim results showed a similar safety profile between NVSI-06-09 and BBIBP-CorV booster groups, with low incidence of adverse reactions of grade 1 or 2. For immunogenicity, by day 14 after the booster vaccination, the fold rises in neutralizing antibody geometric mean titers (GMTs) from baseline level elicited by NVSI-06-09 were remarkably higher than those by BBIBP-CorV against the prototype strain (19.67 vs 4.47-fold), Omicron BA.1.1 (42.35 vs 3.78-fold), BA.2 (25.09 vs 2.91-fold), BA.4 (22.42 vs 2.69-fold), and BA.5 variants (27.06 vs 4.73-fold). Similarly, the neutralizing GMTs boosted by NVSI-06-09 against Beta and Delta variants were also 6.60-fold and 7.17-fold higher than those boosted by BBIBP-CorV. CONCLUSIONSA booster dose of NVSI-06-09 was well-tolerated and elicited broad-spectrum neutralizing responses against SARS-CoV-2 prototype strain and immune-evasive variants, including Omicron and its sub-lineages. The immunogenicity of NVSI-06-09 as a booster vaccine was superior to that of BBIBP-CorV. (Funded by LIBP and BIBP of Sinopharm; ClinicalTrials.gov number, NCT05293548).

3.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-337676

ABSTRACT

Protein-biomolecule interactions play pivotal roles in almost all biological processes, the identification of the interacting protein is essential. By combining a substrate-based proximity labelling activity from the pupylation pathway of Mycobacterium tuberculosis , and the streptavidin (SA)-biotin system, we developed S pecific P upylation as IDE ntity R eporter (SPIDER) for identifying protein-biomolecular interactions. As a proof of principle, SPIDER was successfully applied for global identification of interacting proteins, including substrates for enzyme (CobB), the readers of m 6 A, the protein interactome of mRNA, and the target proteins of drug (lenalidomide). In addition, by SPIDER, we identified SARS-CoV-2 Omicron variant specific receptors on cell membrane and performed in-depth analysis for one candidate, Protein-g. These potential receptors could explain the differences between the Omicron variant and the Prototype strain, and further serve as target for combating the Omicron variant. Overall, we provide a robust technology which is applicable for a wide-range of protein-biomolecular interaction studies.

4.
AMB Express ; 12(1), 2022.
Article in English | ProQuest Central | ID: covidwho-1837317

ABSTRACT

As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to spread globally, a series of vaccines, antibodies and drugs have been developed to combat coronavirus disease 2019 (COVID-19). High specific antibodies are powerful tool for the development of immunoassay and providing passive immunotherapy against SARS-CoV-2 and expected with large scale production. SARS-CoV-2 S1 protein was expressed in E. coli BL21 and purified by immobilized metal affinity chromatography, as antigen used to immunize hens, the specific IgY antibodies were extracted form egg yolk by PEG-6000 precipitation, and the titer of anti-S1 IgY antibody reached 1:10,000. IgY single chain variable fragment antibody (IgY-scFv) was generated by using phage display technology and the IgY-scFv showed high binding sensitivity and capacity to S1 protein of SARS-CoV-2, and the minimum detectable antigen S1 protein concentration was 6 ng/µL. The docking study showed that the multiple epitopes on the IgY-scFv interacted with multiple residues on SARS-CoV-2 S1 RBD to form hydrogen bonds. This preliminary study suggests that IgY and IgY-scFv are suitable candidates for the development of immunoassay and passive immunotherapy for COVID-19 to humans and animals.

5.
Preprint in English | bioRxiv | ID: ppbiorxiv-486173

ABSTRACT

Large-scale populations in the world have been vaccinated with COVID-19 vaccines, however, breakthrough infections of SARS-CoV-2 are still growing rapidly due to the emergence of immune-evasive variants, especially Omicron. It is urgent to develop effective broad-spectrum vaccines to better control the pandemic of these variants. Here, we present a mosaic-type trimeric form of spike receptor-binding domain (mos-tri-RBD) as a broad-spectrum vaccine candidate, which carries the key mutations from Omicron and other circulating variants. Tests in rats showed that the designed mos-tri-RBD, whether used alone or as a booster shot, elicited potent cross-neutralizing antibodies against not only Omicron but also other immune-evasive variants. Neutralizing antibody titers induced by mos-tri-RBD were substantially higher than those elicited by homo-tri-RBD (containing homologous RBDs from prototype strain) or the inactivated vaccine BBIBP-CorV. Our study indicates that mos-tri-RBD is highly immunogenic, which may serve as a broad-spectrum vaccine candidate in combating SARS-CoV-2 variants including Omicron.

6.
Molecular therapy. Nucleic acids ; 27:718-732, 2022.
Article in English | EuropePMC | ID: covidwho-1749327

ABSTRACT

Drug discovery from plants usually focuses on small molecules rather than such biological macromolecules as RNAs. Although plant transfer RNA (tRNA)-derived fragment (tRF) has been associated with the developmental and defense mechanisms in plants, its regulatory role in mammals remains unclear. By employing a novel reverse small interfering RNA (siRNA) screening strategy, we show that a tRF mimic (antisense derived from the 5′ end of tRNAHis(GUG) of Chinese yew) exhibits comparable anti-cancer activity with that of taxol on ovarian cancer A2780 cells, with a 16-fold lower dosage than that of taxol. A dual-luciferase reporter assay revealed that tRF-T11 directly targets the 3′ UTR of oncogene TRPA1 mRNA. Furthermore, an Argonaute-RNA immunoprecipitation (AGO-RIP) assay demonstrated that tRF-T11 can interact with AGO2 to suppress TRPA1 via an RNAi pathway. This study uncovers a new role of plant-derived tRFs in regulating endogenous genes. This holds great promise for exploiting novel RNA drugs derived from nature and sheds light on the discovery of unknown molecular targets of therapeutics. Graphical

7.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-330389

ABSTRACT

The SARS-CoV-2 Omicron variant has become the dominant SARS-CoV-2 variant around the world and exhibits immune escape to current COVID-19 vaccines to some extent due to its numerous spike mutations. Here, we evaluated the immune responses to booster vaccination with intramuscular adenovirus-vectored vaccine (Ad5-nCoV), aerosolized Ad5-nCoV, a recombinant protein subunit vaccine (ZF2001) or homologous inactivated vaccine (CoronaVac) in those who received two doses of inactivated COVID-19 vaccines 6 months prior. We found that the Ad5-nCoV booster induced potent neutralizing activity against the wild-type virus and Omicron variant, while aerosolized Ad5-nCoV generated the greatest neutralizing antibody responses against the Omicron variant at day 28 after booster vaccination, at 14.1-fold that of CoronaVac, 5.6-fold that of ZF2001 and 2.0-fold that of intramuscular Ad5-nCoV. Similarly, the aerosolized Ad5-nCoV booster produced the greatest IFNγ T-cell response at day 14 after booster vaccination. The IFNγ T-cell response to aerosolized Ad5-nCoV was 12.8-fold for CoronaVac, 16.5-fold for ZF2001, and 5.0-fold for intramuscular Ad5-nCoV. Aerosolized Ad5-nCoV booster also produced the greatest spike-specific B cell response. Our findings suggest that inactivated vaccine recipients should consider adenovirus-vectored vaccine boosters in China and that aerosolized Ad5-nCoV may provide a more efficient alternative in response to the spread of the Omicron variant.

8.
Preprint in English | medRxiv | ID: ppmedrxiv-22272521

ABSTRACT

Wastewater surveillance serves as a promising approach to elucidate the silent transmission of SARS-CoV-2 in a given community by detecting the virus in wastewater treatment facilities. This study monitored the viral RNA abundance at one WWTP and three communities during the COVID-19 outbreak in the Yanta district of Xian city from December 2021 to January 2022. To further understand the decay of the coronavirus in sewage pipes, avian infectious bronchitis virus (IBV) was seeded in two recirculating water systems and operated for 90 days. Based on the viral abundance in the wastewater of Xian and the above data regarding the decay of coronavirus in sewage pipes, Monte Carol simulations were performed to estimate the infectious cases in Xian. The results suggested that the delta variant was first detected on Dec-10, five days earlier than the reported date of clinical samples. SARS-CoV-2 was detected on December 18 in the monitored community two days earlier than the first case and was consecutively detected in the following two sampling times. In pipelines without biofilms, the results showed that high temperature significantly reduced the viral RNA abundance by 2.18 log10 GC/L after experiencing 20 km travel distance, while only a 1.68 log10 GC/L reduction was observed in the pipeline with a low water temperature. After 90 days of operation, the biofilm matured in the pipeline in both systems. Reductions of viral RNA abundance of 2.14 and 4.79 log10 GC/L were observed in low- and high-temperature systems with mature biofilms, respectively. Based on the above results, we adjusted the input parameters for Monte Carol simulation and estimated 23.3, 50.1, 127.3 and 524.2 infected persons in December 14, 18, 22 and 26, respectively, which is largely consistent with the clinical reports. This work highlights the viability of wastewater surveillance for the early warning of COVID-19 at both the community and city levels, which represents a valuable complement to clinical approaches.

9.
Preprint in English | medRxiv | ID: ppmedrxiv-22272062

ABSTRACT

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with immune escape ability raises the urgent need for developing cross-neutralizing vaccines against the virus. NVSI-06-08 is a potential broad-spectrum recombinant COVID-19 vaccine that integrates the antigens from multiple SARS-CoV-2 strains into a single immunogen. Here, we evaluated the safety and immunogenicity of NVSI-06-08 as a heterologous booster dose in adults previously vaccinated with the inactivated vaccine BBIBP-CorV in a randomized, double-blind, controlled, phase 2 trial conducted in the United Arab Emirates (NCT05069129). Three groups of healthy adults over 18 years of age (600 participants per group) who had administered two doses of BBIBP-CorV 4-6-month, 7-9-month and >9-month earlier, respectively, were vaccinated with either a homologous booster of BBIBP-CorV or a heterologous booster of NVSI-06-08. The primary outcome was immunogenicity and safety of booster vaccinations. The exploratory outcome was cross-reactive immunogenicity against multiple SARS-CoV-2 variants of concerns (VOCs). The incidence of adverse reactions was low in both booster vaccinations, and the overall safety profile of heterologous boost was quite similar to that of homologous boost. Heterologous NVSI-06-08 booster was immunogenically superior to homologous booster of BBIBP-CorV. Both Neutralizing and IgG antibodies elicited by NVSI-06-08 booster were significantly higher than by the booster of BBIBP-CorV against not only SARS-CoV-2 prototype strain but also multiple VOCs. Especially, the neutralizing activity induced by NVSI-06-08 booster against the immune-evasive Beta variant was no less than that against the prototype strain, and a considerable level of neutralizing antibodies against Omicron (GMT: 367.67; 95%CI, 295.50-457.47) was induced by heterologous booster, which was substantially higher than that boosted by BBIBP-CorV (GMT: 45.03; 95%CI, 36.37-55.74). Our findings showed that NVSI-06-08 was safe and immunogenic as a booster dose following two doses of BBIBP-CorV, which was immunogenically superior to homologous boost with another dose of BBIBP-CorV. Our study also indicated that the design of hybrid antigen may provide an effective strategy for broad-spectrum vaccine developments.

10.
Preprint in English | medRxiv | ID: ppmedrxiv-21268499

ABSTRACT

BackgroundThe increased coronavirus disease 2019 (COVID-19) breakthrough cases pose the need of booster vaccinations. In this study, we reported the safety and immunogenicity of a heterologous boost with a recombinant COVID-19 vaccine (CHO cells), named NVSI-06-07, as a third dose in participants who have previously received two doses of the inactivated vaccine (BBIBP-CorV) at pre-specified time intervals. Using homologous boost with BBIBP-CorV as control, the safety and immunogenicity of the heterologous boost with NVSI-06-07 against various SARS-CoV-2 strains, including Omicron, were characterized. MethodsThis study is a single-center, randomised, double-blinded, controlled phase 2 trial for heterologous boost of NVSI-06-07 in BBIBP-CorV recipients from the United Arab Emirates (UAE). Healthy adults (aged [≥]18 years) were enrolled and grouped by the specified prior vaccination interval of BBIBP-CorV, i.e., 1-3 months, 4-6 months or [≥]6 months, respectively, with 600 individuals per group. For each group, participants were randomly assigned at 1:1 ratio to receive either a heterologous boost of NVSI-06-07 or a homologous booster dose of BBIBP-CorV. The primary outcome was to comparatively assess the immunogenicity between heterologous and homologous boosts at 14 and 28 days post-boosting immunization, by evaluation of the geometric mean titers (GMTs) of IgG and neutralizing antibodies as well as the corresponding seroconversion rate ([≥]4-fold rise in antibody titers). The secondary outcomes were the safety profile of the boosting strategies within 30 days post vaccination. The exploratory outcome was the immune efficacy against Omicron and other variants of concern (VOCs) of SARS-CoV-2. This trial is registered with ClinicalTrials.gov, NCT05033847. FindingsA total of 1800 individuals who have received two doses of BBIBP-CorV were enrolled, of which 899 participants received a heterologous boost of NVSI-06-07 and 901 received a homologous boost for comparison. No vaccine-related serious adverse event (SAE) and no adverse events of special interest (AESI) were reported. 184 (20{middle dot}47%) participants in the heterologous boost groups and 177 (19{middle dot}64%) in the homologous boost groups reported at least one adverse reaction within 30 days. Most of the local and systemic adverse reactions reported were grades 1 (mild) or 2 (moderate), and there was no significant difference in the overall safety between heterologous and homologous boosts. Immunogenicity assays showed that the seroconversion rates in neutralizing antibodies against prototype SARS-CoV-2 elicited by heterologous boost were 89{middle dot}96% - 97{middle dot}52% on day 28 post-boosting vaccination, which was much higher than what was induced by homologous boost (36{middle dot}80% - 81{middle dot}75%). Similarly, in heterologous NVSI-06-07 booster groups, the neutralizing geometric mean titers (GMTs) against the prototype strain increased by 21{middle dot}01 - 63{middle dot}85 folds from baseline to 28 days post-boosting vaccination, whereas only 4{middle dot}20 - 16{middle dot}78 folds of increases were observed in homologous BBIBP-CorV booster group. For Omicron variant, the neutralizing antibody GMT elicited by the homologous boost of BBIBP-CorV was 37{middle dot}91 (95%CI, 30{middle dot}35-47{middle dot}35), however, a significantly higher level of neutralizing antibodies with GMT 292{middle dot}53 (95%CI, 222{middle dot}81-384{middle dot}07) was induced by the heterologous boost of NVSI-06-07, suggesting that it may serve as an effective boosting strategy combating the pandemic of Omicron. The similar results were obtained for other VOCs, including Alpha, Beta and Delta, in which the neutralizing response elicited by the heterologous boost was also significantly greater than that of the homologous boost. In the participants primed with BBIBP-CorV over 6 months, the largest increase in the neutralizing GMTs was obtained both in the heterologous and homologous boost groups, and thus the booster vaccination with over 6 months intervals was optimal. InterpretationOur findings indicated that the heterologous boost with NVSI-06-07 was safe, well-tolerated and immunogenic in adults primed with a full regimen of BBIBP-CorV. Compared to homologous boost with a third dose of BBIBP-CorV, incremental increases in immune responses were achieved by the heterologous boost with NVSI-06-07 against SARS-CoV-2 prototype strain, Omicron variant, and other VOCs. The heterologous BBIBP-CorV/NVSI-06-07 prime-boosting vaccination may be valuable in preventing the pandemic of Omicron. The optimal booster strategy was the heterologous boost with NVSI-06-07 over 6 months after a priming with two doses of BBIBP-CorV. Research in contextO_ST_ABSEvidence before this studyC_ST_ABSWe searched PubMed for clinical trials or prospective/cohort studies involving heterologous booster vaccination in non-immunocompromised population published up to Dec 25, 2021, using the term "(COVID) AND (vaccin*) AND (clinical trial OR cohort OR prospective) AND (heterologous) AND (booster OR prime-boost OR third dose)" with no language restrictions. Nine studies of heterologous prime-boost vaccinations with adenovirus-vector vaccines (ChAdOx1 nCov-19, Oxford-AstraZeneca, Ad26.COV2.S, Janssen) and mRNA vaccines (BNT162b2, Pfizer-BioNtech; mRNA1273, Moderna) were identified. The adenovirus-vector and mRNA heterologous prime-boost vaccination was found to be well tolerated and immunogenic. In individuals primed with adenovirus-vector vaccine, mRNA booster vaccination led to greater immune response than homologous boost. However, varied results were obtained on whether heterologous boost was immunogenically superior to the homologous mRNA prime-boost vaccination. Besides that, A preprint trial in population previously immunized with inactivated vaccines (CoronaVac, Sinovac Biotech) showed that the heterologous boost with adenovirus-vector vaccine (Convidecia, CanSino Biologicals) was safe and induced higher level of live-virus neutralizing antibodies than by the homogeneous boost. A pilot study reported that boosting with BNT162b2 in individuals primed with two doses of inactivated vaccines (BBIBP-CorV) was significantly more immunogenic than homologous vaccination with two-dose of BNT162b2. In addition, a preprint paper demonstrated that heterologous boost of ZF2001, a recombinant protein subunit vaccine, after CoronaVac or BBIBP-CorV vaccination potently improved the immunogenicity. But only a small size of samples was tested in this study and the live-virus neutralization was not detected. Till now, it is still lacking a formal clinical trial to evaluate the immunogenicity and safety of the heterologous prime-boost vaccination with an inactivated vaccine followed by a recombinant protein subunit-based vaccine. Added value of this studyTo our knowledge, this is the first reported result of a large-scale randomised, controlled clinical trial of heterologous prime-boost vaccination with an inactivated vaccine followed by a recombinant protein subunit vaccine. This trial demonstrated that the heterologous prime-booster vaccination with BBIBP-CorV/NVSI-06-07 is safe and immunogenic. Its immunoreactivity is similar to that of homologous vaccination with BBIBP-CorV. Compared to homologous boost, heterologous boost with NVSI-06-07 in BBIBP-CorV recipients elicited significantly higher immunogenicity not only against the SARS-CoV-2 prototype strain but also against Omicron and other variants of concern (VOCs). Implications of all the available evidenceBooster vaccination is considered an effective strategy to improve the protection efficacy of COVID-19 vaccines and control the epidemic waves of SARS-CoV-2. Data from our trial suggested that the booster vaccination of NVSI-06-07 in BBIBP-CorV recipients significantly improved the immune responses against various SARS-CoV-2 strains, including Omicron. Due to no Omicron-specific vaccine available currently, the BBIBP-CorV/NVSI-06-07 heterologous prime-boost might serve as an effective strategy combating Omicron variant. Besides that, BBIBP-CorV has been widely inoculated in population, and thus further boosting vaccination with NVSI-06-07 is valuable in preventing the COVID-19 pandemic. But further studies are needed to assess the long-term protection of BBIBP-CorV/NVSI-06-07 prime-booster vaccination.

11.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-294592

ABSTRACT

Angiotensin-converting enzyme 2 (ACE2), a transmembrane protein, is the main entry point for certain coronaviruses including the new coronavirus SARS-CoV-2 to enter cells. Synthesizing the PET imaging probe Al 18 F-DX600-BCH which is high-affinity ACE2 is aim to detect the expression of ACE2 in body and monitor the therapeutic effect. The Al 18 F-DX600-BCH was obtained manually with a 20.4% ± 5.2% radiochemical yield without attenuation correction and an over 99% purified radiochemical purity, being stable in vitro within 4 hours and cleared rapidly in blood (the half-lives of the distribution phase and clearance phase were 2.12 min and 25.31 min, respectively). Results of both biodistribution and PET imaging showed that Al 18 F-DX600-BCH was highly accumulated in the kidney (SUV kidney/normal > 50), and specific uptake in testis (SUV testis/normal > 10) was observed in rat images. The kidney (++), gastrointestinal (++) and bronchial (+++) cells were evidenced of ACE2 positive by IHC staining of rats. A total of 10 volunteers were enrolled and received PET/CT 1 hour and 2 hours after injection or dynamic PET/CT during 0-330 seconds (NCT04542863), from which strong radioactivity accumulation was mostly observed in the genitourinary system (SUV renal cortex = 32.00, SUV testis = 4.56), and moderate accumulation in conjunctiva and nasal mucosa for several cases. This work firstly reported the probe Al 18 F-DX600-BCH targeting ACE2, conducting preliminary preclinical experiments and a total of 10 clinical transformations, which demonstrated the potential and possibility of non-invasive mapping of ACE2. Trial registration: ClinicalTrials.gov NCT04542863. Registered 9 September 2020.

12.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-293272

ABSTRACT

Angiotensin-converting enzyme 2 (ACE2), a transmembrane protein, is the main entry point for certain coronaviruses including the new coronavirus SARS-CoV-2 to enter cells. Synthesizing the PET imaging probe Al 18 F-DX600-BCH which is high-affinity ACE2 is aim to detect the expression of ACE2 in body and monitor the therapeutic effect. The Al 18 F-DX600-BCH was obtained manually with a 20.4% ± 5.2% radiochemical yield without attenuation correction and an over 99% purified radiochemical purity, being stable in vitro within 4 hours and cleared rapidly in blood (the half-lives of the distribution phase and clearance phase were 2.12 min and 25.31 min, respectively). Results of both biodistribution and PET imaging showed that Al 18 F-DX600-BCH was highly accumulated in the kidney (SUV kidney/normal > 50), and specific uptake in testis (SUV testis/normal > 10) was observed in rat images. The kidney (++), gastrointestinal (++) and bronchial (+++) cells were evidenced of ACE2 positive by IHC staining of rats. A total of 10 volunteers were enrolled and received PET/CT 1 hour and 2 hours after injection or dynamic PET/CT during 0-330 seconds (NCT04542863), from which strong radioactivity accumulation was mostly observed in the genitourinary system (SUV renal cortex = 32.00, SUV testis = 4.56), and moderate accumulation in conjunctiva and nasal mucosa for several cases. This work firstly reported the probe Al 18 F-DX600-BCH targeting ACE2, conducting preliminary preclinical experiments and a total of 10 clinical transformations, which demonstrated the potential and possibility of non-invasive mapping of ACE2. Trial registration: ClinicalTrials.gov NCT04542863. Registered 9 September 2020.

13.
Neurology Perspectives ; 2021.
Article in English | EuropePMC | ID: covidwho-1505423

ABSTRACT

Background The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes the disease COVID-19, has caused a pandemic that has rapidly affected the whole world and caused a significant threat to public health. The aim of this study was to investigate and analyze the social and occupational effects of the COVID-19 pandemic on patients with multiple sclerosis (MS) in three different countries: China, Spain, and Cuba. Methods A cross-sectional survey was designed to assess the social and occupational effects of the COVID-19 pandemic in MS patients in these three countries, using a 25-item anonymous online questionnaire, structured into three sections. Quantitative data are expressed as mean (standard deviation), and quantitative data as absolute frequency and percentage. Results A total of 361 participants responded to the questionnaire: 194 from China, 104 from Spain, and 63 from Cuba. We found no cases of COVID-19 among Chinese patients with MS, and few cases in Spain and Cuba. Respondents reported different levels of impact on relationships with friends, family, and colleagues, and patients in all three countries described increased use of digital or social media platforms. Spanish patients reported a significantly less negative impact than those in Cuba and China. Mental and cognitive effects were similar in all three countries, although China seemed to have a better situation. We also found that the time spent exercising decreased at specific points during the pandemic, but with few changes in dietary habits. Patients reported little or no change in their means of transport in all three countries. Most patients in all three countries reported little or no physical deterioration, especially in Chinese patients (82.47%), compared to the Spanish (70.20%) and Cuban respondents (73.02%). In general, patients from all three countries demonstrated confidence in overcoming the COVID-19 pandemic, although to a lesser extent among Spanish respondents. Conclusions During the pandemic, family support was more effective in China than in Cuba and Spain. Neither COVID-19 infections nor the number of MS relapses increased significantly during lockdown in any of the three countries. Regarding their economic situation, Spanish MS patients reported a significantly less severe negative impact than those in Cuba and China. Patients from all three countries used digital or social media platforms more frequently, probably to maintain personal relationships. Chinese and Cuban respondents were more confident of the control of the pandemic than the Spanish, who were more pessimistic.

14.
Preprint in English | bioRxiv | ID: ppbiorxiv-467529

ABSTRACT

The high mutation rate of COVID-19 and the prevalence of multiple variants strongly support the need for pharmacological options to complement vaccine strategies. One region that appears highly conserved among different genus of coronaviruses is the substrate binding site of the main protease (Mpro or 3CLpro), making it an attractive target for the development of broad-spectrum drugs for multiple coronaviruses. PF-07321332 developed by Pfizer is the first orally administered inhibitor targeting the main protease of SARS-CoV-2, which also has shown potency against other coronaviruses. Here we report three crystal structures of main protease of SARS-CoV-2, SARS-CoV and MERS-CoV bound to the inhibitor PF-07321332. The structures reveal a ligand-binding site that is conserved among SARS-CoV-2, SARS-CoV and MERS-CoV, providing insights into the mechanism of inhibition of viral replication. The long and narrow cavity in the cleft between domains I and II of main protease harbors multiple inhibitor binding sites, where PF-07321332 occupies subsites S1, S2 and S4 and appears more restricted compared with other inhibitors. A detailed analysis of these structures illuminated key structural determinants essential for inhibition and elucidated the binding mode of action of main proteases from different coronaviruses. Given the importance of main protease for the treatment of SARS-CoV-2 infection, insights derived from this study should accelerate the design of safer and more effective antivirals.

15.
Preprint in English | medRxiv | ID: ppmedrxiv-21263898

ABSTRACT

BackgroundCoronavirus disease 2019 (COVID-19) vaccines are effective at helping protect against severe disease and death from variants; however, incident of breakthrough infection in vaccinated patients has been increased. Therefore, we aimed to assess the incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) new variants of concern in the communities and investigate vaccine breakthrough cases on our laboratory (Ayass Bioscience LLC) confirmed detection of COVID-19 variants in Dallas-Fort Worth (DFW), Texas. MethodsEpidemiologic study has been performed at our laboratory. We studied the viral whole-genome sequence and genotyping analysis on 166 symptomatic cases of COVID-19 which were randomly selected from nasal swab positive cases assessed from June 1st to August 30th, 2021, by reverse transcription polymerase chain reaction (RT-PCR) cycle threshold (CT) values. COVID-19 variants were identified to be dominated by B.1.617.2 (89.2%) and followed by AY.3 (1.8%), B.1.1.7 (4.8%), a combination of B.1.526.1 and B.1.617.2 (3%), B.1.621 (0.6%), and P.2 (0.6%). ResultThe CT values showed significant difference among the three age groups: <30 years, 31-60 years, and >60 years by one-way ANOVA (N1: F (2, 118) =4.96, p=0.009; N2: F (2, 118) =4.95, p=0.009). No significant difference was observed by symptom, status of immunization, or vaccine manufacturer. A two-way ANOVA was performed to examine the effect of gender and variant group (Delta and other variants) on the CT values. The analyses revealed a statistically significant interaction between the effect of gender and variant group (N1, F (1.117) = 3.906, p = 0.05; N2, F (1, 117) = 7.402, p = 0.008). ConclusionOur study shows that Delta, the dominant variant of COVID-19, is spreading in the communities, and vaccine breakthrough cases occurred in the majority of Delta variant (91%) followed by AY.3 (5%), B.1.1.7 (2%) and 2% of the double variant of B.1.526.1 and B.1.617.2. The incidence of the breakthrough cases was not linked to a specific manufacturer. The CT value is likely to associate with age. This study also supports our laboratorys ongoing efforts to sequence the SARS-CoV-2 virus from positive patient samples to identify the new viral variants and possible vaccine breakthrough mutations in the community.

16.
Drug Evaluation Research ; 43(9):1685-1692, 2020.
Article in Chinese | CAB Abstracts | ID: covidwho-1395260

ABSTRACT

Objective: Analyzed the prescriptions of traditional Chinese medicine (TCM) for patients diagnosed with Novel Coronavirus Pneumonia (COVID-19), and the medication patterns were statistically analyzed to provide reference for the treatment of COVID-19.

17.
Preprint in English | bioRxiv | ID: ppbiorxiv-409144

ABSTRACT

Coronavirus disease 2019 (COVID-19) includes the cardiovascular complications in addition to respiratory disease. SARS-CoV-2 infection impairs endothelial function and induces vascular inflammation, leading to endotheliitis. SARS-CoV-2 infection relies on the binding of Spike glycoprotein (S protein) to angiotensin converting enzyme 2 (ACE2) in the host cells. We show here that S protein alone can damage vascular endothelial cells (ECs) in vitro and in vivo, manifested by impaired mitochondrial function, decreased ACE2 expression and eNOS activity, and increased glycolysis. The underlying mechanism involves S protein downregulation of AMPK and upregulation of MDM2, causing ACE2 destabilization. Thus, the S protein-exerted vascular endothelial damage via ACE2 downregulation overrides the decreased virus infectivity.

18.
Preprint in English | bioRxiv | ID: ppbiorxiv-155812

ABSTRACT

Main protease (Mpro, also known as 3CLpro) has a major role in the replication of coronavirus life cycle and is one of the most important drug targets for anticoronavirus agents. Here we report the crystal structure of main protease of SARS-CoV-2 bound to a previously identified Chinese herb inhibitor shikonin at 2.45 angstrom resolution. Although the structure revealed here shares similar overall structure with other published structures, there are several key differences which highlight potential features that could be exploited. The catalytic dyad His41-Cys145 undergoes dramatic conformational changes, and the structure reveals an unusual arrangement of oxyanion loop stabilized by the substrate. Binding to shikonin and binding of covalent inhibitors show different binding modes, suggesting a diversity in inhibitor binding. As we learn more about different binding modes and their structure-function relationships, it is probable that we can design more effective and specific drugs with high potency that can serve as effect SARS-CoV-2 anti-viral agents.

19.
Preprint in English | bioRxiv | ID: ppbiorxiv-092171

ABSTRACT

Mpro is of considerable interest as a drug target in the treatment of COVID-19 since the proteolytic activity of this viral protease is essential for viral replication. Here we report the first insight of the structure Mpro for SARS-CoV-2 in the inactive conformation under conditions close to the physiological state (pH 7.5) to an overall resolution of 1.9 [A]. The comparisons of Mpro in different states reveal that substrate binding site and the active site are more flexible in the inactive conformation than that in the active conformations. Notably, compared with the active conformation of the apo state structure in pH7.6 of SARS, the SARS-CoV-2 apo state is in the inactive conformation under condition close to physiological state (pH7.5). Two water molecules are present in the oxyanion hole in our apo state structure, whereas in the ligand-bound structure, water molecular is absence in the same region. This structure provides novel and important insights that have broad implications for understanding the structural basis underlying enzyme activity, and can facilitate rational, structure-based, approaches for the design of specific SARS-CoV-2 ligands as new therapeutic agents.

20.
Preprint in English | medRxiv | ID: ppmedrxiv-20030916

ABSTRACT

Corona Virus Disease 2019 (COVID-19) has spread rapidly to more than 70 countries and regions overseas and over 80000 cases have been infected, resulting in more than three thousand deaths. Rapid diagnosis of patients remains a bottleneck in containing the progress of the epidemic. We used automated chemiluminescent immunoassay to detect serum IgM and IgG antibodies to 2019-nCoV of 736 subjects. COVID-19 patients were becoming reactive(positive) for specific antibodies from 7-12 days after the onset of morbidity. Specific IgM and IgG increased with the progression of the disease. The areas under the ROC curves of IgM and IgG were 0.988 and 1.000, respectively. Specific antibody detection has good sensitivity and specificity. Detection of specific antibodies in patients with fever can be a good distinction between COVID-19 and other diseases, so as to be a complement to nucleic acid diagnosis to early diagnosis of suspected cases.

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