Pharmacokinetics and safety of a new generic lurasidone: a phase I bioequivalence study in healthy Chinese subjects.

Latuda® is a novel antipsychotic drug for schizophrenia and bipolar depression. A bioequivalence trial was performed to investigate the bioequivalence of Latuda® and its generic drug lurasidone. Two independent trials were carried out, each involving 28 subjects. In the fasting trial, subjects were randomly assigned to two groups (1:1 ratio), receiving either 40 mg of generic lurasidone or Latuda®. After a 7-day washout period, subjects entered the second period with a crossover administration of 40 mg of generic lurasidone or Latuda®. The postprandial study design was similar to that of the fasting study. In the fasting study, the pharmacokinetic (PK) parameter values of generic lurasidone and Latuda® were as follows: the Cmax was 28.84 ± 19.34 ng/ml and 28.22 ± 21.19 ng/ml, respectively; the AUC0-t was 121.39 ± 58.47 h*ng/ml and 118.35 ± 52.24 h*ng/ml, respectively; and the AUC0-∞ was 129.63 ± 63.26 h*ng/ml and 126.59 ± 57.99 h*ng/ml, respectively. The primary pharmacokinetic parameter, Cmax, was assessed for equivalence using reference-scaled average bioequivalence (RSABE), while other parameters (AUC0-t, AUC0-∞) were evaluated using average bioequivalence (ABE). The results indicate that both Cmax and AUC meet the equivalence criteria. In the postprandial study, the PK values of generic lurasidone and Latuda® were as follows: the Cmax was 74.89 ± 32.06 ng/ml and 83.51 ± 33.52 ng/ml, respectively; the AUC0-t was 274.77 ± 103.05 h*ng/ml and 289.26 ± 95.25 h*ng/ml, respectively; and the AUC0-∞ was 302.44 ± 121.60 h*ng/ml and 316.32 ± 109.04 h*ng/ml, respectively. The primary pharmacokinetic parameters (Cmax, AUC0-t, AUC0-∞) were assessed for equivalence using ABE, and both met the equivalence criteria. In the study, lurasidone and Latuda® both exhibited acceptable safety and tolerability. The results displayed that lurasidone and Latuda® were bioequivalent and safe in healthy Chinese participants. Clinical Trial Registry: This trial is registered at chinadrugtrials.org.cn (no.: CTR20191717, date: 2019.08.29).

Analysis of influencing factors on long COVID in COVID-19 patients infected with omicron variant three months after discharge: a cross-sectional study.

BACKGROUND: The purpose of this study is to analyze the influencing factors associated with Long-COVID in patients infected with Omicron variant of COVID-19 in Changchun City, Jilin Province, China three months after discharge in March 2022. METHODS: In this study, we conducted a telephone follow-up based on the real-world data collected from the Affiliated Hospital to Changchun University of Chinese Medicine, Changchun Tongyuan Shelter Hospital and Changchun Infectious Disease Hospital during the COVID-19 epidemic in Changchun in March 2022. We used the Global COVID-19 Clinical Platform Case Report Form for Post COVID condition as a follow-up questionnaire to collect the general information, past medical history, clinical symptoms, COVID-19 vaccine inoculation doses, and other relevant information to analyze the symptom characteristics of COVID-19 patients three months after discharge from the hospital and related factors affecting Long COVID. RESULTS: A total of 1,806 patients with COVID-19 were included in this study, 977 males and 829 females, with a mean age of 38.5 [30.0, 49.4] years, and the number of female patients suffering from Long COVID (50.87%) was greater than male patients (p = 0.023). The binary logistic regression analysis of factors influencing Long COVID showed that smoking history (OR (95%CI) = 0.551(0.425-0.714), p < 0.001, taking never smoking as a reference), allergy history (OR (95%CI) = 1.618 (1.086-2.413), p-value 0.018, taking no allergy as a reference), first symptoms (OR (95%CI) = 0.636 (0.501-0.807), p < 0.001, with no first symptoms as reference) and COVID-19 vaccine inoculation doses (OR (95%CI) = 1.517 (1.190-1.933), p-value 0.001, with ≤ 2 doses of COVID-19 vaccine inoculation doses as reference) constituted its influencing factors. The first symptoms of patients on admission mainly included fever (512 cases, 71.81%), cough (279 cases, 39.13%) and dry or itchy throat (211 cases, 29.59%). The most common symptoms of Long COVID were persistent fatigue (68 cases), amnesia (61 cases), insomnia (50 cases) and excessive sweating (50 cases). CONCLUSION: The first symptoms on admission were predominantly fever, cough and dry or itchy throat. The most common symptoms of Long COVID were persistent fatigue, amnesia, insomnia and excessive sweating, and female patients were at a higher risk of Long COVID.

miRNA dosage control in development and human disease.

In mammals, miRNAs recognize target mRNAs via base pairing, which leads to a complex 'multiple-to-multiple' regulatory network. Previous studies have focused on the regulatory mechanisms and functions of individual miRNAs, but alterations of many individual miRNAs do not strongly disturb the miRNA regulatory network. Recent studies revealed the important roles of global miRNA dosage control events in physiological processes and pathogenesis, suggesting that miRNAs can be considered as a 'cellular buffer' that controls cell fate. Here, we review the current state of research on how global miRNA dosage is tightly controlled to regulate development, tumorigenesis, neurophysiology, and immunity. We propose that methods of controlling global miRNA dosage may serve as effective therapeutic tools to cure human diseases.

Comparing the bioequivalence and safety of liraglutide in healthy Chinese subjects: an open, single-dose, randomized, repeated, two-sequence, two-cycle phase I clinical trial.

BACKGROUND: Glucagon-like peptide-1 (GLP-1) is an endogenous incretin hormone. Liraglutide, a GLP-1 receptor agonist, can lower blood sugar by increasing insulin production and inhibiting the production of glucagon. This study researched the bioequivalence and safety of the test and reference drugs in healthy Chinese subjects. RESEARCH DESIGN AND METHODS: Subjects (N = 28) were randomly divided into group A and group B at a ratio of 1:1 for a two-cycle cross-over study. There was single dose per cycle with subcutaneous injection of the test and reference drugs, respectively. The washout was set at 14 days. Plasma drug concentrations were detected by specific liquid chromatography and tandem mass spectrometry (LC-MS/MS) assays. Statistical analysis of major pharmacokinetic (PK) parameters was conducted to assess drug bioequivalence. In addition, we evaluated the safety of the drugs throughout the trial. RESULTS: The geometric mean ratios (GMRs) of Cmax, AUC0-t, and AUC0-∞ for the test and reference drugs were 107.11%, 106.56%, 106.09%, respectively. The 90% confidence intervals (CIs) were all within 80%-125%, meeting the bioequivalence standards. In addition, both had good safety in this study. CONCLUSION: The study shows that the two drugs had similar bioequivalence and safety. CLINICAL TRIAL REGISTRATION: DCTR: CTR20190914; ClinicalTrials.gov: NCT05029076.

Pharmacokinetics and safety of dasatinib and its generic: a phase I bioequivalence study in healthy Chinese subjects.

BACKGROUND: Dasatinib (Sprycel®) is a tyrosine kinase inhibitor for treating chronic myeloid leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia. RESEARCH DESIGN & METHODS: We designed a clinical study to demonstrate that the dasatinib tablet (YiNiShu®) (Chia Tai Tianqing Pharmaceutical Group Co., Ltd) and Dasatinib (Bristol Myers Squibb) were bioequivalent under fasting and fed conditions. The whole study was structured into the fasting trial and the postprandial trial. Each period, subjects were given 50 mg dasatinib or its generic. The RSABE (reference scale average bioequivalence) and ABE (average bioequivalence) methods were employed to assess bioequivalence by pharmacokinetics (PK) parameters for a highly variable drug. RESULTS: 32 and 24 eligible volunteers were enrolled in the fasting and postprandial trials, respectively. In the fasting trial, the RSABE method was performed, and point estimates of Cmax, AUC0-t, and AUC0-∞ met the bioequivalence criteria. In the postprandial trial, the ABE method was performed, and the 90% CI of the geometric mean ratio (GMR) for PK parameters met the requirements of bioequivalence standards. CONCLUSION: The results proved that the PK parameters of the two drugs were similar and bioequivalent, indicating that both drugs had a good safety profile. CLINICAL TRIAL REGISTRATION: This trial was registered in ClinicalTrials.gov (Number: NCT05640804) and Drug Clinical Trial Registration and Information Disclosure Platform (Number: CTR20181708).

Reporting Quality of Oral TCM Systematic Reviews Based on the PRISMA Harms Checklist from 2013 to 2020.

Background: Systematic reviews focusing on the effectiveness of different kinds of healthcare interventions have been widely published, but there were few guidelines for reporting safety concerns before 2016. The PRISMA harms checklist, which was published in 2016, can standardize reporting quality. Objectives: To evaluate the safety information reporting quality of oral traditional Chinese medicine (TCM) in systematic reviews before and after the PRISMA harms checklist was published and to explore factors associated with better reporting. Methods: We searched PubMed, the Cochrane Library, and Embase to identify all systematic reviews using oral TCM as interventions published before (from 2013 to 2015) and after (from 2017 to 2020) the PRISMA harms checklist was published. We used the PRISMA harms checklist to assess the quality of reporting of the safety information to included systematic reviews. Results: In total, 200 systematic reviews were sampled from eligible studies published between 2013 and 2020. Reviews from 2016 were excluded. Scores on the PRISMA harms checklist (23 items) ranged from 0 to 12. A systematic reviews published after 2016 had better reporting quality compared with studies published before 2016 with regard to the title (P=0.03), results of individual studies (P=0.016), and risk of bias across studies (P=0.043). In all included systematic reviews of our study, the state conclusion in coherence with review findings was reported adequately with the proportion of adherence at 95%; other items had a reporting proportion ranging from 0% to 57%. The four essential reporting items of the PRISMA harms checklist also had a low reporting quality ranging from 0% to 4%. Conclusions: Oral TCM systematic reviews reported inadequate safety information before and after the PRISMA harms checklist was published. This survey suggested that the PRISMA harms checklist should be recommended more to both original research and systematic review authors.

[Academic characteristics of contemporary famous traditional Chinese medicine experts and schools in treatment of chronic renal failure based on SrTO].

According to the systematic review of text and opinion(SrTO) developed by the Joanna Briggs Institute(JBI), this study integrated the evidence of the medical cases, papers, medical experience, and other related research of famous experts and schools on the treatment of chronic renal failure in the field of traditional Chinese medicine(TCM) nephropathy, analyzed the academic characteristics and influencing factors from the aspects of the principle, method, recipe, and medicines, and explored the internal logic and law of inheritance and innovation in TCM nephropathy. A total of 36 famous TCM experts and 4 schools were included. The work areas are concentrated in North and South China. 94.0% of the famous TCM experts have experienced master-disciple teaching. 27.8% have studied TCM through family succession. 38.9% have been taught by multiple famous teachers. And 5.6% have not experienced master-disciple teaching. In terms of principle, method, recipe, and medicines, many innovations have been made, with 30.6% of famous TCM experts proposing new theories, 11.1% advocating staged treatment of chronic renal failure, and 47.2% summarizing the treatment methods. The formation of the academic thoughts of contemporary famous TCM experts and schools on the treatment of chronic renal failure is closely related to the learning mode, era, and work area. Contemporary famous TCM experts and schools have the academic characteristics of combining classical and clinical theories and paying more attention to TCM with western medicine supplemented. The field of TCM nephropathy has the characteristics of simultaneous inheritance and innovation. On the basis of inheriting the classical theories of TCM, it absorbs modern medical theories, combines clinical diagnosis with the syndrome and treatment law of contemporary diseases, and makes innovations in principle, method, recipe, and medicines, which has significant clinical efficacy in the treatment of chronic renal failure.

Comparative the efficacy and acceptability of immunosuppressive agents for myasthenia gravis: A protocol for systematic review and network meta-analysis.

BACKGROUND: Immunosuppressive drugs are routinely used to treat myasthenia gravis (MG). However, current recommendations provide limited evidence to support treatment options, leading to considerable variation in practice among healthcare specialists. Hence, we present a protocol for a systematic review and network meta-analysis (NMA) to update the evidence by comparing the efficacy and acceptability of oral immunosuppressive drugs for the treatment of MG. METHODS: We will conduct a systematic review and NMA of all randomized controlled trials evaluating the following oral immunosuppressive drugs for the treatment of MG. Published studies will be searched using the following databases from inception to November 23, 2021: CENTRAL, the CINAHL, MEDLINE, Embase, PsycINFO, Web of Science, and 3 Chinese databases (Chinese Biomedical Literatures Database, CNKI, and Wan Fang database). Assessment of study eligibility and data extraction will be conducted independently by 2 reviewers. The main outcome will be a quantitative MG scoring system. We will conduct Bayesian NMA to synthesize all evidence for each outcome and obtain a comprehensive ranking of all treatments. The quality of the evidence will be evaluated using the Grading of Recommendations, Assessment, Development, and Evaluations framework. RESULTS: The objective of this study was to assess the relative clinical efficacy and acceptability of first-line immunosuppressants for the treatment of MG, using a systematic review and NMA approach. CONCLUSION: In the absence of head-to-head trials comparing therapies, evidence from this NMA of available clinical trials will inform clinicians, patients, and families the risk-benefit profiles of different treatment options.

Exploring the Potential Mechanism of Qi-Shen-Di-Huang Drug Formulary for Myasthenia Gravis (MG) based on UHPLC-QE-MS Network Pharmacology and Molecular Docking Techniques.

Myasthenia gravis (MG) is a rare and refractory autoimmune disease, and Qi Shen Di Huang (QSDH) drug formulary is an in-hospital herbal decoction with proven clinical efficacy in treating MG. Currently, most of the research on the QSDH drug formulary has concentrated on its clinical efficacy, and there is a lack of systematic study on the material basis. The active compounds and their mechanism of action have not been entirely determined. Therefore, this study sought to identify the active compounds in the QSDH drug formulary and analyze the key targets and potential mechanisms. We used ultra-performance liquid chromatography Q Exactive-mass spectrometry (UHPLC-QE-MS) and Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) database to identify and screen 85 active ingredients corresponding to 59 potential targets (17 herbs) associated with myasthenia gravis, and further identified AKT1 as the primary core target and the PI3K/AKT signaling pathway as the most substantial enriched pathway. Molecular docking and UPLC-MS analysis identified quercetin, luteolin, wogonin, kaempferol, laccasein, and epigallocatechin gallate are the core compounds of the QSDH drug formulary. In vivo rat studies showed that the QSDH drug formulary reduced Lennon's clinical score and decreased acetylcholine receptor antibody levels in peripheral blood rats with experimental autoimmune myasthenia gravis. In addition, the QSDH drug formulary downregulated P-PI3K/PI3K and P-Akt/Akt protein expression. Collectively, these findings describe the role and potential mechanism of the QSDH drug formulary in the treatment of MG, which exerts potential value by acting on AKT targets and regulating the PI3K/AKT signaling pathway and providing a theoretical reference for QSDH drug formulary application in the clinical treatment of MG.

Corrigendum: Pharmacokinetics, Immunogenicity and Safety Study for SHR-1309 Injection and Perjeta® in Healthy Chinese Male Volunteers.

[This corrects the article DOI: 10.3389/fphar.2021.660541.].

A randomized, open-label, single-dose, two-cycle crossover study to evaluate the bioequivalence and safety of lenvatinib and Lenvima® in Chinese healthy subjects.

BACKGROUND: Lenvatinib is a tyrosine kinase receptor inhibitor that inhibits vascular and endothelial growth factor receptor kinase activity. This study evaluated the bioequivalence and safety of lenvatinib with Lenvima® . RESEARCH DESIGN AND METHODS: The fasting and postprandial groups were two independent trials. Subjects were randomly divided into two sequences at a ratio of 1:1 for two-cycle crossover administration. Subjects took 10 mg lenvatinib or Lenvima® once per cycle. The wash-out period was 14 days. Detected the plasma drug concentrations and assessed the bioequivalence of two drugs. Besides, we evaluated the safety of the drugs throughout the trial. RESULTS: In the fasting state, the GMRs of Cmax, AUC0-t, and AUC0-∞ were 99.89%, 102.98% and 103.19%, respectively. The 90% CIs were all within 80%-125%. In the postprandial state, the GMRs of Cmax, AUC0-t, and AUC0-∞ were 98.96%, 94.25% and 95.27%, respectively. The 90% CIs were all within 80%-125%. All results met the bioequivalence criteria. Both drugs had good safety and tolerance in this trial. CONCLUSION: This study showed that lenvatinib and Lenvima® had similar bioequivalence and safety in healthy Chinese subjects under fasting and postprandial conditions. CLINICAL TRIAL REGISTRATION: This trial is registered at the Chinese Clinical Trial website (http://www.chinadrugtrials.org.cn/index.html # CTR20191172).

Molecular basis of differential receptor usage for naturally occurring CD55-binding and -nonbinding coxsackievirus B3 strains.

Receptor usage defines cell tropism and contributes to cell entry and infection. Coxsackievirus B (CVB) engages coxsackievirus and adenovirus receptor (CAR), and selectively utilizes the decay-accelerating factor (DAF; CD55) to infect cells. However, the differential receptor usage mechanism for CVB remains elusive. This study identified VP3-234 residues (234Q/N/V/D/E) as critical population selection determinants during CVB3 virus evolution, contributing to diverse binding affinities to CD55. Cryoelectron microscopy (cryo-EM) structures of CD55-binding/nonbinding isolates and their complexes with CD55 or CAR were obtained under both neutral and acidic conditions, and the molecular mechanism of VP3-234 residues determining CD55 affinity/specificity for naturally occurring CVB3 strains was elucidated. Structural and biochemical studies in vitro revealed the dynamic entry process of CVB3 and the function of the uncoating receptor CAR with different pH preferences. This work provides detailed insight into the molecular mechanism of CVB infection and contributes to an in-depth understanding of enterovirus attachment receptor usage.

A randomized, double-blind, single-dose, single-center, parallel phase I clinical study comparing the pharmacokinetics, immunogenicity, safety, and tolerance of pertuzumab injection and Perjeta® in healthy Chinese male subjects.

BACKGROUND: Perjeta® is a recombinant, humanized monoclonal antibody that has been marketed and approved for the targeted therapy of human epidermal growth factor receptor (HER2) positive breast cancer in the United States. This study compared the bioequivalence, immunogenicity, and safety of pertuzumab injection (a biosimilar of Perjeta® produced by Chia Tai Tianqing Pharmaceutical Group Co., Ltd) and Perjeta® (produced by Roche Pharma AG) in healthy Chinese males. RESEARCH DESIGN AND METHODS: Healthy Chinese male subjects (N = 87) were randomly given intravenous injection of 5 mg/kg pertuzumab or Perjeta® at a 1:1 ratio. Plasma drug concentrations were detected by enzyme-linked immunosorbent assay, and primary pharmacokinetic parameters were statistically analyzed. We detected the levels of anti-drug antibody (ADA) and neutralizing antibody (nAb) to evaluate drug immunogenicity and safety of the drugs throughout the study. RESULTS: The geometric mean ratios of AUC0-t, Cmax, and AUC0-∞ for pertuzumab and Perjeta® were 100.42%, 96.71%, and 101.47%, respectively. The 90% CIs were all within 80%-125%, meeting the bioequivalence standards. The levels of ADA and nAb were similar. In addition, both had good safety in the study. CONCLUSION: The study shows that pertuzumab injection and Perjeta® had similar bioequivalence, immunogenicity, and safety.

Pharmacokinetics, Immunogenicity and Safety Study for SHR-1309 Injection and Perjeta® in Healthy Chinese Male Volunteers.

Objectives: Pertuzumab is a monoclonal antibody for the treatment of breast cancer. The aim of this study was to compare the pharmacokinetics, immunogenicity and safety of the test preparation SHR-1309 injecta and the reference preparation Perjeta® in healthy Chinese male subjects. Methods: In this randomized, double-blind, single dose, two-way, parallel bioequivalence trial, a total of 80 qualified Chinese male subjects were selected and randomly divided into two groups. Each subject was intravenously injected with SHR-1309 or Perjeta®. Blood samples were collected at 21 different time points for pharmacokinetic analysis. In addition, immunogenicity was assessed at five different time points. The safety of the medication was monitored throughout the whole trial. Results: Cmax and AUC0-t were the primary pharmacokinetic parameters. Under a 90% confidence interval, their geometric mean ratios were 98.30 and 88.41% for SHR-1309 injection and Perjeta®, respectively. The geometric mean ratio of secondary pharmacokinetic parameters AUC0-∞ was 88.58%. These evaluation indexes are in the standard range of 80-125%, so SHR-1309 can be considered bioequivalent to Perjeta®. After 1,680 h (day 70) of administration, the two groups had 12 and 13 subjects who produced antidrug antibody (ADA), respectively. The occurrence time and proportion of ADA in SHR-1309 and Perjeta® were similar between subjects, and they had similar immunogenicity. During the entire trial period, there were 71 drug-related adverse reactions in 29 subjects who received SHR-1309 and 61 drug-related adverse reactions in 32 subjects who received Perjeta®. The incidence of adverse reactions between the two drugs was similar. Conclusion: The pharmacokinetic parameters, immunogenicity and safety of the biosimilar SHR-1309 injection produced by Shanghai Hengrui Pharmaceutical Co. Ltd. were similar to the original drug Perjeta® produced by Roche Pharma AG. The two drugs met the bioequivalence evaluation criteria. Therefore, SHR-1309 is bioequivalent to Perjeta®. Clinical trial registration: CTR20200,738.

Global miRNA dosage control of embryonic germ layer specification.

MicroRNAs (miRNAs) have essential functions during embryonic development, and their dysregulation causes cancer1,2. Altered global miRNA abundance is found in different tissues and tumours, which implies that precise control of miRNA dosage is important1,3,4, but the underlying mechanism(s) of this control remain unknown. The protein complex Microprocessor, which comprises one DROSHA and two DGCR8 proteins, is essential for miRNA biogenesis5-7. Here we identify a developmentally regulated miRNA dosage control mechanism that involves alternative transcription initiation (ATI) of DGCR8. ATI occurs downstream of a stem-loop in DGCR8 mRNA to bypass an autoregulatory feedback loop during mouse embryonic stem (mES) cell differentiation. Deletion of the stem-loop causes imbalanced DGCR8:DROSHA protein stoichiometry that drives irreversible Microprocessor aggregation, reduced primary miRNA processing, decreased mature miRNA abundance, and widespread de-repression of lipid metabolic mRNA targets. Although global miRNA dosage control is not essential for mES cells to exit from pluripotency, its dysregulation alters lipid metabolic pathways and interferes with embryonic development by disrupting germ layer specification in vitro and in vivo. This miRNA dosage control mechanism is conserved in humans. Our results identify a promoter switch that balances Microprocessor autoregulation and aggregation to precisely control global miRNA dosage and govern stem cell fate decisions during early embryonic development.

Profiles of COVID-19 clinical trials in the Chinese Clinical Trial Registry.

The COVID-19 pandemic has caused a global public health crisis. There is a pressing need for evidence-based interventions to address the devastating clinical and public health effects of the COVID-19 pandemic. The Chinese scientists supported by private and government resources have adopted extensive efforts to identify effective drugs against the virus. To date, a large number of clinical trials addressing various aspects of COVID19 have been registered in the Chinese Clinical Trial Registry (ChiCTR), including more than 200 interventional studies. Under such an urgent circumstance, the scope and quality of these clinical studies vary significantly. Hence, this review aims to make a comprehensive analysis on the profiles of COVID-19 clinical trials registered in the ChiCTR, including a wide range of characteristics. Our findings will provide a useful summary on these clinical studies since most of these studies will encounter major challenges from the design to completion. It will be a long road for the outcomes of these studies to be published and international collaboration will help the ultimate goals of developing new vaccines and anti-viral drugs.

Molecular basis of Coxsackievirus A10 entry using the two-in-one attachment and uncoating receptor KRM1.

KREMEN1 (KRM1) has been identified as a functional receptor for Coxsackievirus A10 (CV-A10), a causative agent of hand-foot-and-mouth disease (HFMD), which poses a great threat to infants globally. However, the underlying mechanisms for the viral entry process are not well understood. Here we determined the atomic structures of different forms of CV-A10 viral particles and its complex with KRM1 in both neutral and acidic conditions. These structures reveal that KRM1 selectively binds to the mature viral particle above the canyon of the viral protein 1 (VP1) subunit and contacts across two adjacent asymmetry units. The key residues for receptor binding are conserved among most KRM1-dependent enteroviruses, suggesting a uniform mechanism for receptor binding. Moreover, the binding of KRM1 induces the release of pocket factor, a process accelerated under acidic conditions. Further biochemical studies confirmed that receptor binding at acidic pH enabled CV-A10 virion uncoating in vitro. Taken together, these findings provide high-resolution snapshots of CV-A10 entry and identify KRM1 as a two-in-one receptor for enterovirus infection.

Structures of human-infecting Thogotovirus fusogens support a common ancestor with insect baculovirus.

Thogotoviruses are emerging tick-borne zoonotic orthomyxoviruses infecting both humans and domestic animals with severe clinical consequences. These viruses utilize a single-envelope glycoprotein (Gp) to facilitate their entry into host cells. Here, we present the Gp structures of Thogoto and Dhori viruses, both of which are members of the Thogotovirus genus in the family Orthomyxoviridae These structures, determined in the postfusion conformation, identified them as class III viral fusion proteins. It is intriguing that the Gp structures are similar to the envelope protein of baculovirus, although sharing a low sequence identity of ∼28%. Detailed structural and phylogenic analyses demonstrated that these Gps originated from a common ancestor. Among the structures, domain I is the most conserved region, particularly the fusion loops. Domain II showed the highest variability among different viruses, which might be related to their distinct host tropism. These findings increase our understanding of the divergent evolution processes of various orthomyxoviruses and indicate potential targets for developing antiviral therapeutics by intercepting virus entry.

In vitro assembly of Ebola virus nucleocapsid-like complex expressed in E. coli.

Ebola virus (EBOV) harbors an RNA genome encapsidated by nucleoprotein (NP) along with other viral proteins to form a nucleocapsid complex. Previous Cryo-eletron tomography and biochemical studies have shown the helical structure of EBOV nucleocapsid at nanometer resolution and the first 450 amino-acid of NP (NPΔ451-739) alone is capable of forming a helical nucleocapsid-like complex (NLC). However, the structural basis for NP-NP interaction and the dynamic procedure of the nucleocapsid assembly is yet poorly understood. In this work, we, by using an E. coli expression system, captured a series of images of NPΔ451-739 conformers at different stages of NLC assembly by negative-stain electron microscopy, which allowed us to picture the dynamic procedure of EBOV nucleocapsid assembly. Along with further biochemical studies, we showed the assembly of NLC is salt-sensitive, and also established an indispensible role of RNA in this process. We propose the diverse modes of NLC elongation might be the key determinants shaping the plasticity of EBOV virions. Our findings provide a new model for characterizing the self-oligomerization of viral nucleoproteins and studying the dynamic assembly process of viral nucleocapsid in vitro.