Research progress on non-protein-targeted drugs for cancer therapy.

Non-protein target drugs, especially RNA-based gene therapies for treating hereditary diseases, have been recognized worldwide. As cancer is an insurmountable challenge, no miracle drug is currently available. With the advancements in the field of biopharmaceuticals, research on cancer therapy has gradually focused on non-protein target-targeted drugs, especially RNA therapeutics, including oligonucleotide drugs and mRNA vaccines. This review mainly summarizes the clinical research progress in RNA therapeutics and highlights that appropriate target selection and optimized delivery vehicles are key factors in increasing the effectiveness of cancer treatment in vivo.

Intraduodenal Delivery of Exosome-Loaded SARS-CoV-2 RBD mRNA Induces a Neutralizing Antibody Response in Mice.

Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), has presented numerous challenges to global health. Vaccines, including lipid-based nanoparticle mRNA, inactivated virus, and recombined protein, have been used to prevent SARS-CoV-2 infections in clinics and have been immensely helpful in controlling the pandemic. Here, we present and assess an oral mRNA vaccine based on bovine-milk-derived exosomes (milk-exos), which encodes the SARS-CoV-2 receptor-binding domain (RBD) as an immunogen. The results indicate that RBD mRNA delivered by milk-derived exosomes can produce secreted RBD peptides in 293 cells in vitro and stimulates neutralizing antibodies against RBD in mice. These results indicate that SARS-CoV-2 RBD mRNA vaccine loading with bovine-milk-derived exosomes is an easy, cheap, and novel way to introduce immunity against SARS-CoV-2 in vivo. Additionally, it also can work as a new oral delivery system for mRNA.

Comorbid anxiety and depressive symptoms and the related factors among international medical students in China during COVID-19 pandemic: a cross-sectional study.

BACKGROUND: The two most prevalent mental health conditions are anxiety and depression and they often coexist (comorbidity) in an individual aggravating the person's psychological or medical conditions. College students suffered from anxiety and depressive symptoms during the COVID-19 pandemic, according to numerous studies. The lack of information on the comorbidity of anxiety and depression (CAD) among international medical students, however, makes it difficult to develop effective policies or strategies to support these students. OBJECTIVE: The present research seeks to investigate the incidence of CAD among international medical students in China and to identify the variables that may be useful in predicting CAD. METHOD: A cross-sectional study was conducted at China Medical University in Shenyang, China, for international medical students during November 2020. A total of 519 international students provided information on their demographics, stress related to the COVID-19 pandemic, generalized anxiety disorder assessment (GAD-7), patient health questionnaire-9 (PHQ-9), simplified coping style questionnaire (SCSQ), perceived stress scale (PSS-10), the multidimensional scale of perceived social support (MSPSS), revised life orientation test (LOT-R), and resilience scale-14 (RS-14). To investigate the potential predictors of CAD, a chi-square test, a nonparametric test, and multinomial logistic regression analyses were carried out as appropriate. RESULTS: The incidence of anxiety, depression, and CAD in the current study was 5.8%, 8.9%, and 22.7%, respectively. The predictors for students having symptoms of anxiety were observed to be the negative coping style (ß = 0.662, OR = 1.938, CI:1.07-3.694) and perceived stress (ß = 0.167, OR = 1.181, CI:1.076-1.297); the predictors for students having symptoms of depression were observed to be the COVID-19 pandemic-related stress (ß = 0.323,OR = 1.382,CI:1.211-1.577), negative coping style (ß = 0.693,OR = 2.000, CI:1.21-3.568), and perceived stress (ß = 0.135,OR = 1.145,CI:1.050-1.248); whereas the predictors for students with CAD were observed to be staying up late (Yes VS No) (ß = 1.028,OR = 2.794,CI:1.227-6.364), current place of residence (Other continents VS China) (ß = -1.413, OR = 0.243,CI:0.065-0.910), COVID-19 pandemic-related stress (ß = 0.371,OR = 1.450,CI:1.284-1.636), negative coping style (ß = 1.092,OR = 2.979,CI:1.706-5.203), and perceived stress (ß = 0.339,OR = 1.403,CI:1.289-1.527). CONCLUSION: Single anxiety and depressive symptoms were moderately prevalent among international medical students in China. However, CAD turned out to be the most prevalent mental health issue due to its relatively higher incidence. Negative coping style and perceived stress were the communal predictors of the three categories, whereas stress related to the COVID-19 pandemic was linked to both depression and CAD, and staying up late and in residential places were specific predictors for CAD. Study results suggest that COVID-19 pandemic-related stress was related to students' CAD and depressive symptoms, and specific intervention measures with stress reduction, proper coping strategy, and a good lifestyle might be useful in improving the international students' mental health status.

Identification of the regulatory mechanism of ACE2 in COVID-19-induced kidney damage with systems genetics approach.

Studies showed that SARS-CoV-2 can directly target the kidney and induce renal damage. As the cell surface receptor for SARS-CoV-2 infection, the angiotensin-converting enzyme 2 (ACE2) plays a pivotal role for renal physiology and function. Thus, it is important to understand ACE2 through which pathway influences the pathogenesis of renal damage induced by COVID-19. In this study, we first performed an eQTL mapping for Ace2 in kidney tissues in 53 BXD mice strains. Results demonstrated that Ace2 is highly expressed and strongly controlled by a genetic locus on chromosome 16 in the kidney, with six genes (Dnase1, Vasn, Usp7, Abat, Mgrn1, and Rbfox1) dominated as the upstream modulator, as they are highly correlated with Ace2 expression. Gene co-expression analysis showed that Ace2 co-variates are significantly involved in the renin-angiotensin system (RAS) pathway which acts as a reno-protector. Importantly, we also found that Ace2 is positively correlated with Pdgf family members, particularly Pdgfc, which showed the most association among the 76 investigated growth factors. Mammalian Phenotype Ontology enrichment indicated that the cognate transcripts for both Ace2 and Pdgfc were mainly involved in regulating renal physiology and morphology. Among which, Cd44, Egfr, Met, Smad3, and Stat3 were identified as hub genes through protein-protein interaction analysis. Finally, in aligning with our systems genetics findings, we found ACE2, pdgf family members, and RAS genes decreased significantly in the CAKI-1 kidney cancer cells treated with S protein and receptor binding domain structural protein. Collectively, our data suggested that ACE2 work with RAS, PDGFC, as well as their cognate hub genes to regulate renal function, which could guide for future clinical prevention and targeted treatment for COVID-19-induced renal damage outcomes. KEY MESSAGES: • Ace2 is highly expressed and strongly controlled by a genetic locus on chromosome 16 in the kidney. • Ace2 co-variates are enriched in the RAS pathway. • Ace2 is strongly correlated with the growth factor Pdgfc. • Ace2 and Pdgfc co-expressed genes involved in the regulation of renal physiology and morphology. • SARS-CoV-2 spike glycoprotein induces down-regulation of Ace2, RAS, and Pdgfc.

A pan-sarbecovirus vaccine based on RBD of SARS-CoV-2 original strain elicits potent neutralizing antibodies against XBB in non-human primates.

The recently emerged Omicron subvariants XBB and BQ.1.1 have presented striking immune evasion against most monoclonal neutralizing antibodies and convalescent plasma. Therefore, it is essential to develop broad-spectrum COVID-19 vaccines to combat current and future emerging variants. Here, we found that the human IgG Fc-conjugated RBD of the original SARS-CoV-2 strain (WA1) plus a novel STING agonist-based adjuvant CF501 (CF501/RBD-Fc) could induce highly potent and durable broad-neutralizing antibody (bnAb) responses against Omicron subvariants, including BQ.1.1 and XBB in rhesus macaques with NT50s ranging from 2,118 to 61,742 after three doses. A decline of 0.9- to 4.7-fold was observed in the neutralization activity of sera in the CF501/RBD-Fc group against BA.2.2, BA.2.9, BA.5, BA.2.75, and BF.7 relative to D614G after three doses, while a significant decline of NT50 against BQ.1.1 (26.9-fold) and XBB (22.5-fold) relative to D614G. However, the bnAbs were still effective in neutralizing BQ.1.1 and XBB infection. These results suggest that the conservative but nondominant epitopes in RBD could be stimulated by CF501 to generate bnAbs, providing a proof-of-concept for using "nonchangeable against changeables" strategy to develop pan-sarbecovirus vaccines against sarbecoviruses, including SARS-CoV-2 and its variants.

SARS-CoV-2 Omicron XBB subvariants exhibit enhanced fusogenicity and substantial immune evasion in elderly population, but high sensitivity to pan-coronavirus fusion inhibitors.

Numerous emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron subvariants have shown significant immune evasion capacity and caused a large number of infections, as well as vaccine-breakthrough infections, especially in elderly populations. Recently emerged Omicron XBB was derived from the BA.2 lineage, but bears a distinct mutant profile in its spike (S) protein. In this study, we found that Omicron XBB S protein drove more efficient membrane-fusion kinetics on human lung-derived cells (Calu-3). Considering the high susceptibility of the elderly to the current Omicron pandemic, we performed a comprehensive neutralization assessment of elderly convalescent or vaccine sera against XBB infection. We found that the sera from elderly convalescent patients who experienced with BA.2 infection or breakthrough infection potently inhibited BA.2 infection, but showed significantly reduced efficacy against XBB. Moreover, recently emerged XBB.1.5 subvariant also showed more significant resistance to the convalescent sera of BA.2- or BA.5-infected elderly. On the other hand, we found that the pan-CoV fusion inhibitors EK1 and EK1C4 can potently block either XBB-S- or XBB.1.5-S-mediated fusion process and viral entry. Moreover, EK1 fusion inhibitor showed potent synergism when combined with convalescent sera of BA.2- or BA.5-infected patients against XBB and XBB.1.5 infection, further indicating that EK1-based pan-CoV fusion inhibitors are promising candidates for development as clinical antiviral agents to combat the Omicron XBB subvariants.

Development and validation of a prognostic model based on immune variables to early predict severe cases of SARS-CoV-2 Omicron variant infection.

Background: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant has prevailed globally since November 2021. The extremely high transmissibility and occult manifestations were notable, but the severity and mortality associated with the Omicron variant and subvariants cannot be ignored, especially for immunocompromised populations. However, no prognostic model for specially predicting the severity of the Omicron variant infection is available yet. In this study, we aim to develop and validate a prognostic model based on immune variables to early recognize potentially severe cases of Omicron variant-infected patients. Methods: This was a single-center prognostic study involving patients with SARS-CoV-2 Omicron variant infection. Eligible patients were randomly divided into the training and validation cohorts. Variables were collected immediately after admission. Candidate variables were selected by three variable-selecting methods and were used to construct Cox regression as the prognostic model. Discrimination, calibration, and net benefit of the model were evaluated in both training and validation cohorts. Results: Six hundred eighty-nine of the involved 2,645 patients were eligible, consisting of 630 non-ICU cases and 59 ICU cases. Six predictors were finally selected to establish the prognostic model: age, neutrophils, lymphocytes, procalcitonin, IL-2, and IL-10. For discrimination, concordance indexes in the training and validation cohorts were 0.822 (95% CI: 0.748-0.896) and 0.853 (95% CI: 0.769-0.942). For calibration, predicted probabilities and observed proportions displayed high agreements. In the 21-day decision curve analysis, the threshold probability ranges with positive net benefit were 0~1 and nearly 0~0.75 in the training and validation cohorts, correspondingly. Conclusions: This model had satisfactory high discrimination, calibration, and net benefit. It can be used to early recognize potentially severe cases of Omicron variant-infected patients so that they can be treated timely and rationally to reduce the severity and mortality of Omicron variant infection.

Supercoiling Structure-Based Design of a Trimeric Coiled-Coil Peptide with High Potency against HIV-1 and Human ß-Coronavirus Infection.

Hexameric structure formation through packing of three C-terminal helices and an N-terminal trimeric coiled-coil core has been proposed as a general mechanism of class I enveloped virus entry. In this process, the C-terminal helical repeat (HR2) region of viral membrane fusion proteins becomes transiently exposed and accessible to N-terminal helical repeat (HR1) trimer-based fusion inhibitors. Herein, we describe a mimetic of the HIV-1 gp41 HR1 trimer, N3G, as a promising therapeutic against HIV-1 infection. Surprisingly, we found that in addition to protection against HIV-1 infection, N3G was also highly effective in inhibiting infection of human ß-coronaviruses, including MERS-CoV, HCoV-OC43, and SARS-CoV-2, possibly by binding the HR2 region in the spike protein of ß-coronaviruses to block their hexameric structure formation. These studies demonstrate the potential utility of anti-HIV-1 HR1 peptides in inhibiting human ß-coronavirus infection. Moreover, this strategy could be extended to the design of broad-spectrum antivirals based on the supercoiling structure of peptides.

Viral Entry Inhibitors Targeting Six-Helical Bundle Core against Highly Pathogenic Enveloped Viruses with Class I Fusion Proteins.

Type Ⅰ enveloped viruses bind to cell receptors through surface glycoproteins to initiate infection or undergo receptor-mediated endocytosis and initiate membrane fusion in the acidic environment of endocytic compartments, releasing genetic material into the cell. In the process of membrane fusion, envelope protein exposes fusion peptide, followed by an insertion into the cell membrane or endosomal membrane. Further conformational changes ensue in which the type 1 envelope protein forms a typical six-helix bundle structure, shortening the distance between viral and cell membranes so that fusion can occur. Entry inhibitors targeting viral envelope proteins, or host factors, are effective antiviral agents and have been widely studied. Some have been used clinically, such as T20 and Maraviroc for human immunodeficiency virus 1 (HIV-1) or Myrcludex B for hepatitis D virus (HDV). This review focuses on entry inhibitors that target the six-helical bundle core against highly pathogenic enveloped viruses with class I fusion proteins, including retroviruses, coronaviruses, influenza A viruses, paramyxoviruses, and filoviruses.

Recent computational drug repositioning strategies against SARS-CoV-2.

Since COVID-19 emerged in 2019, significant levels of suffering and disruption have been caused on a global scale. Although vaccines have become widely used, the virus has shown its potential for evading immunities or acquiring other novel characteristics. Whether current drug treatments are still effective for people infected with Omicron remains unclear. Due to the long development cycles and high expense requirements of de novo drug development, many researchers have turned to consider drug repositioning in the search to find effective treatments for COVID-19. Here, we review such drug repositioning and combination efforts towards providing better handling. For potential drugs under consideration, aspects of both structure and function require attention, with specific categories of sequence, expression, structure, and interaction, the key parameters for investigation. For different data types, we show the corresponding differing drug repositioning methods that have been exploited. As incorporating drug combinations can increase therapeutic efficacy and reduce toxicity, we also review computational strategies to reveal drug combination potential. Taken together, we found that graph theory and neural network were the most used strategy with high potential towards drug repositioning for COVID-19. Integrating different levels of data may further improve the success rate of drug repositioning.

Long-Acting Protective Ocular Surface by Instilling Adhesive Dual-Antiviral Nanoparticles.

The eye is susceptible to viral infections, causing severe ocular symptoms or even respiratory diseases. Methods capable of protecting the eye from external viral invasion in a long-term and highly effective way are urgently needed but have been proved to be extremely challenging. Here, a strategy of forming a long-acting protective ocular surface is described by instilling adhesive dual-antiviral nanoparticles. Taking pseudotyped severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as a model virus, antiviral agent-loaded nanoparticles are coated with a "double-lock" hybrid cell membrane abundant with integrin-ß1 and angiotensin converting enzyme II (ACE2). After instillation, the presence of integrin-ß1 endows coated nanoparticles with steady adhesion via specific binding to Arg-Gly-Asp sequence on the fibronectin of ocular epithelium, achieving durable retention on the ocular surface. In addition to loaded inhibitors, the exposure of ACE2 can trap SARS-CoV-2 and subsequently neutralize the associated spike protein, playing a dual antiviral effect of the resulting nanoparticles. Adhesive dual-antiviral nanoparticles enabled by coating with a "double-lock" hybrid cell membrane could be a versatile platform for topical long-acting protection against viral infection of the eye.

Safety of inactivated COVID-19 vaccines in autoimmune encephalitis: A real-world cross-sectional survey.

OBJECTIVE: To assess safety data of the inactivated COVID-19 vaccines in a real-world sample of people with autoimmune encephalitis (pwAE). METHODS: A cross-sectional study was performed between 1 March and 30 April 2022. We invited pwAE from our previous ONE-WC (Outcome of Autoimmune Encephalitis Study in Western China) registration study database, to attend neurological clinics, at West China Hospital to participate in a face-to-face survey using a custom-designed questionnaire for this study. The ONE-WC study began in October 2011 and prospectively enrolled pwAE from four large comprehensive neurological centers in Sichuan province, China. RESULTS: Of the 387 pwAE, 240 (62.0%) completed the questionnaire. Half the 240 participants (121, 50.4%) reported receiving at least one dose of COVID-19 vaccine, which in all but two patients received inactivated COVID-19 vaccine. Among vaccinated pwAE, the median age was 35 years (range 15-69) and 57.8% of them were women. The most frequent reasons that unvaccinated individuals reported for not receiving the COVID-19 vaccine were concern about vaccine-induced relapse of AE (50.4%) and advice from a physician to delay vaccination (21.0%). Small proportions of vaccinated individuals reported adverse events after the first dose (11.5%) or the second dose (10.2%), and none of the adverse events was serious. Across the entire sample, one individual reported relapsing within 30 days after the first dose and three individuals reported relapsing more than 120 days after the first dose. CONCLUSIONS: This real-world survey indicates an overall favorable safety profile of the inactivated COVID-19 vaccine for pwAE.

Probing the Affinity of Noble Metal Nanoparticles to the Segments of the SARS-CoV-2 Spike Protein

Currently, scientists have devoted great efforts to finding effective treatments to combat Covid-19 infections. Although noble metal nanoparticles are able to realize protein modifications, their interactions with the protein are still unclear from the atomic perspective. To supply a general understanding, in this work, we have carried out theoretical calculations to investigate the interaction between protein segments (RBD1, RBD2, RBD3) of SARS-Cov-2 spike protein and a series of noble metal (Au, Ag, Cu, Pd, Pt) surfaces regarding the binding strength, protein orientation, and electronic modulations. In particular, the Au surface has shown the strongest binding preferences for the protein segments, which induces electron transfer between the Au and receptor-binding domain (RBD) segments. This further leads to the polarization of segments for virus denaturation. This work has offered a direct visualization of protein interactions with noble metal surfaces from the atomic level, which will benefit anti-virus material developments in the future. Graphical

Development of variant-proof severe acute respiratory syndrome coronavirus 2, pan-sarbecovirus, and pan-ß-coronavirus vaccines.

The newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with high transmission rates and striking immune evasion have posed a serious challenge to the application of current first-generation SARS-CoV-2 vaccines. Other sarbecoviruses, such as SARS-CoV and SARS-related coronaviruses (SARSr-CoVs), have the potential to cause outbreaks in the future. These facts call for the development of variant-proof SARS-CoV-2, pan-sarbecovirus or pan-ß-CoV vaccines. Several novel vaccine platforms have been used to develop vaccines with broad-spectrum neutralizing antibody responses and protective immunity to combat the current SARS-CoV-2 and its variants, other sarbecoviruses, as well as other ß-CoVs, in the future. In this review, we discussed the major target antigens and protective efficacy of current SARS-CoV-2 vaccines and summarized recent advances in broad-spectrum vaccines against sarbecoviruses and ß-CoVs.

SARS-CoV-2 Omicron subvariants exhibit distinct fusogenicity, but similar sensitivity, to pan-CoV fusion inhibitors.

Continuous emergence of the Omicron variant, along with its subvariants, has caused an increasing number of infections, reinfections, and vaccine-breakthrough infections, seriously threatening human health. Recently, several new Omicron subvariants, such as BA.5, BA.2.75, BA.4.6, and BF.7, bearing distinct mutation profiles in their spike (S) proteins, have significantly increased their capacity to evade vaccine-induced immunity and have shown enhanced infectivity and transmissibility, quickly becoming dominant sublineages. In this study, we found the S proteins of these Omicron subvariants to have 2- to 4-fold more efficient membrane fusion kinetics than that of the original Omicron variant (BA.1), indicating that these novel Omicron subvariants might possess increased pathogenicity. We also identified that peptide-based pan-CoV fusion inhibitors, EK1 and EK1C4, showed equal efficacy against membrane fusion mediated by S proteins of the noted Omicron subvariants and infection by their pseudoviruses. Additionally, either immune sera induced by wild-type (WT) SARS-CoV-2 RBD-based vaccine or BA.2 convalescent sera showed potent synergism with EK1 against both WT SARS-CoV-2 and various Omicron subvariants, further suggesting that EK1-based fusion inhibitors are promising candidates for development as clinical antiviral agents against the currently circulating Omicron subvariants.