Functional and structural investigation of a broadly neutralizing SARS-CoV-2 antibody.

Since its emergence, SARS-CoV-2 has been continuously evolving, hampering the effectiveness of current vaccines against COVID-19. mAbs can be used to treat patients at risk of severe COVID-19. Thus, the development of broadly protective mAbs and an understanding of the underlying protective mechanisms are of great importance. Here, we isolated mAbs from donors with breakthrough infection with Omicron subvariants using a single-B cell screening platform. We identified a mAb, O5C2, which possesses broad-spectrum neutralization and antibody-dependent cell-mediated cytotoxic activities against SARS-CoV-2 variants, including EG.5.1. Single-particle analysis by cryo-electron microscopy revealed that O5C2 targeted an unusually large epitope within the receptor-binding domain of spike protein that overlapped with the angiotensin-converting enzyme 2 binding interface. Furthermore, O5C2 effectively protected against BA.5 Omicron infection in vivo by mediating changes in transcriptomes enriched in genes involved in apoptosis and interferon responses. Our findings provide insights into the development of pan-protective mAbs against SARS-CoV-2.

Comparisons on the intraoperative desaturation and postoperative outcomes in non-intubated video-assisted thoracic surgery with supraglottic airway devices or high-flow nasal oxygen: A retrospective study.

BACKGROUND: Few studies have compared intraoperative oxygenation and perioperative outcomes between non-intubated video-assisted thoracic surgery (NIVATS) with supraglottic airway devices (SADs) and NIVATS with high flow nasal oxygenation (HFNO). The aim of this retrospective study was to compare the intraoperative desaturation rate and postoperative outcomes between NIVATS with SADs and NIVATS with HFNO. METHODS: Data regarding NIVATS performed for lung cancer from January 2020 to December 2021 were collected. Intraoperative anesthetic results, post-anesthetic adverse effects, and surgical outcomes for patients who received SAD or HFNO were analyzed using propensity score-matched and unmatched analysis. RESULTS: In total, 199 patients with i-gel™ and 95 patients with HFNO were included. Significantly more female patients (91.6 vs. 82.4%, p = 0.0378) and fewer wedge resections (78.9 vs. 85.4%, p = 0.0258) were observed in the HFNO group. Among 250 patients who underwent NIVATS wedge resections under total intravenous anesthesia, those who received HFNO had a significantly higher desaturation event rate (19.8% vs. 7.9% in i-gel™ group; p = 0.0063), lower nadir SPO2 (94.0% vs. 96.1% in i-gel™ group; p = 0.0012), and longer hospitalization (4.0 ± 0.8 vs. 3.6 ± 0.6 in i-gel™ group; p < 0.0001). However, propensity score matching analysis revealed no significant between-group difference in the desaturation rate. A log-rank test revealed that smoking (p = 0.0005) and HFNO (p = 0.0074) were associated with intraoperative desaturation. CONCLUSION: The rate of SAD use in NIVATS was twice the rate of HFNO use, especially for wedge resections. There is uncertain airway patency and limited flow through HFNO during one-lung ventilation, whereas SADs like i-gel™ presented a significantly less intraoperative desaturation rate over time and similar postoperative outcomes.

Immunoglobulin Y Specific for SARS-CoV-2 Spike Protein Subunits Effectively Neutralizes SARS-CoV-2 Infectivity and Ameliorates Disease Manifestations In Vivo.

(Background) The coronavirus disease 2019 (COVID-19) that is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) carries high infectivity and mortality. Efficient intervention strategies are urgently needed. Avian immunoglobulin Y (IgY) showed efficacy against viral infection whereas the in vivo efficacy remains unclear. (Methods) We immunized laying hens with S1, S1 receptor-binding domain (S1-RBD), or S2 subunits of the SARS-CoV-2 spike (S) protein. After immunization, IgYs were collected and extracted from the egg yolks. The neutralization potential of IgYs was examined by the plaque reduction neutralization test (PRNT). The bioutility of IgYs was examined in Syrian hamsters in vivo. (Results) IgYs exhibited typical banding patterns in SDS-PAGE and Western blot and were immunoreactive against S1, S1-RBD, and S2 subunits. The plaque reduction neutralization test (PRNT) showed that all purified IgYs potently neutralized different SARS-CoV-2 strains in vitro. In Syrian hamsters, the combination of IgYs for S1-RBD and S2 subunits administered before or after SARS-CoV-2 infection effectively restored body weight loss and reduced intrapulmonary lesions and the amount of immunoreactive N protein-positive cells, which were caused by SARS-CoV-2 infection. (Conclusions) Collectively, IgYs specific for S protein subunits effectively neutralized SARS-CoV-2 in vitro and in vivo and may serve as prophylactic or therapeutic antibodies in the prevention or treatment of COVID-19.

Influenza A virus NS1 protein represses antiviral immune response by hijacking NF-κB to mediate transcription of type III IFN.

Background: Non-structural protein 1 (NS1), one of the viral proteins of influenza A viruses (IAVs), plays a crucial role in evading host antiviral immune response. It is known that the IAV NS1 protein regulates the antiviral genes response mainly through several different molecular mechanisms in cytoplasm. Current evidence suggests that NS1 represses the transcription of IFNB1 gene by inhibiting the recruitment of Pol II to its exons and promoters in infected cells. However, IAV NS1 whether can utilize a common mechanism to antagonize antiviral response by interacting with cellular DNA and immune-related transcription factors in the nucleus, is not yet clear. Methods: Chromatin immunoprecipitation and sequencing (ChIP-seq) was used to determine genome-wide transcriptional DNA-binding sites for NS1 and NF-κB in viral infection. Next, we used ChIP-reChIP, luciferase reporter assay and secreted embryonic alkaline phosphatase (SEAP) assay to provide information on the dynamic binding of NS1 and NF-κB to chromatin. RNA sequencing (RNA-seq) transcriptomic analyses were used to explore the critical role of NS1 and NF-κB in IAV infection as well as the detailed processes governing host antiviral response. Results: Herein, NS1 was found to co-localize with NF-κB using ChIP-seq. ChIP-reChIP and luciferase reporter assay confirmed the co-localization of NS1 and NF-κB at type III IFN genes, such as IFNL1, IFNL2, and IFNL3. We discovered that NS1 disturbed binding manners of NF-κB to inhibit IFNL1 expression. NS1 hijacked NF-κB from a typical IFNL1 promoter to the exon-intron region of IFNL1 and decreased the enrichment of RNA polymerase II and H3K27ac, a chromatin accessibility marker, in the promoter region of IFNL1 during IAV infection, consequently reducing IFNL1 gene expression. NS1 deletion enhanced the enrichment of RNA polymerase II at the IFNL1 promoter and promoted its expression. Conclusion: Overall, NS1 hijacked NF-κB to prevent its interaction with the IFNL1 promoter and restricted the open chromatin architecture of the promoter, thereby abating antiviral gene expression.

Tumor Necrosis Factor-Alpha Exacerbates Viral Entry in SARS-CoV2-Infected iPSC-Derived Cardiomyocytes.

The coronavirus disease 2019 (COVID-19) pandemic with high infectivity and mortality has caused severe social and economic impacts worldwide. Growing reports of COVID-19 patients with multi-organ damage indicated that severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) may also disturb the cardiovascular system. Herein, we used human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (iCMs) as the in vitro platform to examine the consequence of SARS-CoV2 infection on iCMs. Differentiated iCMs expressed the primary SARS-CoV2 receptor angiotensin-converting enzyme-II (ACE2) and the transmembrane protease serine type 2 (TMPRSS2) receptor suggesting the susceptibility of iCMs to SARS-CoV2. Following the infection of iCMs with SARS-CoV2, the viral nucleocapsid (N) protein was detected in the host cells, demonstrating the successful infection. Bioinformatics analysis revealed that the SARS-CoV2 infection upregulates several inflammation-related genes, including the proinflammatory cytokine tumor necrosis factor-α (TNF-α). The pretreatment of iCMs with TNF-α for 24 h, significantly increased the expression of ACE2 and TMPRSS2, SASR-CoV2 entry receptors. The TNF-α pretreatment enhanced the entry of GFP-expressing SARS-CoV2 pseudovirus into iCMs, and the neutralization of TNF-α ameliorated the TNF-α-enhanced viral entry. Collectively, SARS-CoV2 elevated TNF-α expression, which in turn enhanced the SARS-CoV2 viral entry. Our findings suggest that, TNF-α may participate in the cytokine storm and aggravate the myocardial damage in COVID-19 patients.

Zinc finger protein ZFP36L1 inhibits influenza A virus through translational repression by targeting HA, M and NS RNA transcripts.

ZFP36L1, a CCCH-type zinc finger protein, is an RNA-binding protein that participates in controlling cellular mRNA abundance and turnover by posttranscriptional regulation. Here, we demonstrated that ZFP36L1 has an important role in host defense against influenza A virus (IAV) infection. Overexpression of ZFP36L1 reduced IAV replication via translational repression of HA, M and NS RNA segment transcripts. IAV infection upregulated cellular ZFP36L1 expression, and endogenous ZFP36L1 knockdown significantly enhanced IAV replication. ZFP36L1 directly binds to IAV NS1 mRNA in the cytoplasm and blocks the expression and function of NS1 protein. Mutation of CCCH-type zinc finger domains of ZFP36L1 lost its antiviral potential and NS1 mRNA binding. Thus, ZFP36L1 can act as a host innate defense by targeting HA, M and NS mRNA transcripts to suppress viral protein translation.

Rapid Induction and Maintenance of Remission in Refractory Ulcerative Colitis with Ustekinumab.

Ulcerative colitis is a chronic debilitating disease characterized by relapsing in intestinal inflammation and ulcers with no available cure. This is a clinical case report of a 52-year-old female patient with 30 years history of left-sided chronic ulcerative colitis controlled with standard of care (mesalamine and azathioprine) which subsequently relapsed and developed into active refractory ulcerative colitis. The patient became unresponsive to her medications including different forms of mesalamines and did not respond favorably to any of the other current therapies. Numerous attempts to stabilize her condition with immunosuppressants, steroids, probiotics, antibiotics, mesalamines, and various biologic agents failed to improve her clinical symptoms, and the patient was being considered for colectomy. As the last resort, modified therapy was prescribed with ustekinumab, a non-selective, anti-IL12/23 p40 monoclonal antibody. This medication has not been yet approved for use in ulcerative colitis patients. In this clinical case we report the efficacy of ustekinumab to rapidly induce and maintain remission of the severe chronic ulcerative colitis in the patient. To the best of our knowledge, this is the first report of utilizing ustakinamub therapy for rapid induction in an active refractory ulcerative colitis patient resulting in complete remission for over one year.

Core-shell of FePt@SiO2-Au magnetic nanoparticles for rapid SERS detection.

In this study, multifunctional hybrid nanoparticles composed of iron platinum (FePt), silica (SiO2), and gold nanoparticles (AuNPs) had been developed for surface-enhanced Raman scattering (SERS) application. Core-shell structure of SiO2 and FePt nanoparticles (FePt@SiO2) was fabricated through sol-gel process and then immobilized gold nanoparticles onto the surface of FePt@SiO2, which displays huge Raman enhancement effect and magnetic separation capability. The resulting core-shell nanoparticles were subject to evaluation by transmission electron microscopy (TEM), Energy-dispersive X-ray spectroscopy (EDX), zeta potential measurement, and X-ray photoelectron spectroscopy (XPS). TEM observation revealed that the particle size of resultant nanoparticles displayed spherical structure with the size ~30 nm and further proved the successful immobilization of Au onto the surface of FePt@SiO2. Zeta potential measurement exhibited the successful reaction between FePt@SiO2 and AuNPs. The rapid SERS detection and identification of small biomolecules (adenine) and microorganisms (gram-positive bacteria, Staphylococcus aureus) was conducted through Raman spectroscopy. In summary, the novel core-shell magnetic nanoparticles could be anticipated to apply in the rapid magnetic separation under the external magnetic field due to the core of the FePt superparamagnetic nanoparticles and label-free SERS bio-sensing of biomolecules and bacteria.

[Effects of root cutting under different seedling conditions on root system distribution and senescence character of peanut].

The effects of root cutting on root system distribution and senescence character of peanut (Arachis hypogaea) under different seedling conditions were investigated by using the box culture method. The results showed that, with three types of peanut seedlings, including overgrowing, strong and week seedlings, root cutting all first restricted and then promoted the root system growth, especially promoted the root growth to deep soil. This effect was stronger on the overgrowing and strong seedlings, while relatively weaker on the weak seedlings. After root cutting, root activity, superoxide dismutase (SOD) and peroxidase (POD) activity all reduced at first, and then increased, compared with each control. The extents of decrease in root activity, SOD and POD activity were highest in the weak seedlings, lowest in the overgrowing seedlings, and moderate in the strong seedlings. However, in the later stage after root cutting, the extents of increase in root activity, SOD and POD activity were higher in the overgrowing and strong seedlings, than in the weak seedlings. Generally, root cutting could promote the root activity of peanut and delay the senescence.

[The circuit design of an alarm system for the old solitary man based on daily life].

The system with DS1302 as its clock makes one hour as one basic time unit, and thus there will be 24 monitoring segments in a day. It watches the movements of the aged through the sensors placed in the house-rooms such as bedroom, kitchen, and obtains the data of the movements and activities. Based on the data the MCU (Micro Control Unit) will make an hourly judgment whether the movements and activities are normal ones. When the system makes sure they are abnormal, it will dial out the setting telephone saved in EEPROM, waiting for the other end to pick up phone and then will send the tone alarm out. Once an accident happens, the alarm will be started up immediately by pressing the emergency button of the remote control. When the aged is out, he or she can shift the health mode to the away mode by the remote control, and the system will act as a home security system. In simulation experiments, the system works well at recognizing the data of movements and has a very low mis-alarm ratio. The system provides a viable solution to the social problem of looking after the aged who lives alone.