The genetic diversity of genogroup I noroviruses causing acute gastroenteritis outbreaks in Beijing between 2014 and 2023.

Background: In the past decade, we have continuously conducted sporadic monitoring and outbreak detection of norovirus (NoV), which causes human acute gastroenteritis (AGE) in the capital of China. Accumulated data have shown that genogroup I (GI) NoVs not only cause sporadic cases but also cannot be ignored during outbreaks. This study aimed to update the genetic diversity of GI NoVs in the capital of China from 2014 to 2023.

Identification and Activity Study of an Impurity Band Observed in the nrSDS-PAGE of Aflibercept.

Background: Aflibercept is a biopharmaceutical targeting vascular endothelial growth factor (VEGF) that has shown promise in the treatment of neovascular age-related macular degeneration (nAMD) and diabetic macular edema (DME) in adults. Quality control studies of aflibercept employing non-reduced SDS-PAGE (nrSDS-PAGE) have shown that a significant variant band (IM1) is consistently present below the main band. Considering the quality control strategy of biopharmaceuticals, structural elucidation and functional studies are required.

In-depth characterization of a cysteine-linked ADC disitamab vedotin by multiple LC-MS analysis methods and cutting-edge imaged capillary isoelectric focusing coupled with native mass spectrometry.

The characterization of cysteine-linked antibody‒drug conjugates (ADCs) can be more challenging than that of monoclonal antibodies (mAbs) and lysine-linked ADCs because the interchain disulfide bonds are reduced for payload conjugation, and the chains are noncovalently bonded to each other. Furthermore, payload conjugation and disulfide bond reduction/scrambling may introduce additional charge heterogeneity to biomolecules. This study illustrates an innovative workflow employing multiple separation techniques and tandem high-resolution mass spectrometry for comprehensive and in-depth characterization of disitamab vedotin, a recent-generation cysteine-linked ADC, including reversed-phase liquid chromatography (RPLC), ion exchange chromatography (IEX) and image capillary isoelectric focusing (icIEF).

Possibility of using the imaged capillary isoelectric method as a multi-attribute method for bispecific antibodies.

An imaged capillary isoelectric focusing (icIEF)-based method was developed and validated as a multi-attribute method for a bispecific antibody (BsAb). First, as the traditional application of the icIEF method, it serves as an identity assay and purity assay for the BsAb. Second, the method can also be used as an impurity assay for the homodimer monoclonal antibodies generated during BsAb assembly.

A combination of multiple LC-MS approaches for the comprehensive characterization of cysteine-linked ADCs.

Antibody-drug conjugates (ADCs) represent the forefront of the next generation of biopharmaceuticals. An ADC typically comprises an antibody covalently linked to a cytotoxic drug via a linker, resulting in a highly heterogeneous product. This study focuses on the analysis of a custom-made cysteine-linked ADC.

A native SEC-MS workflow and validation for analyzing drug-to-antibody ratio and drug load distribution in cysteine-linked antibody-drug conjugates.

The development and optimization of Antibody-Drug Conjugates (ADCs) hinge on enhanced analytical and bioanalytical characterization, particularly in assessing critical quality attributes (CQAs). The ADC's potency is largely determined by the average number of drugs attached to the monoclonal antibody (mAb), known as the drug-to-antibody ratio (DAR). Furthermore, the drug load distribution (DLD) influences the therapeutic window of the ADC, defining the range of dosages effective in treating diseases without causing toxic effects.

Mass spectrometry study on SARS-CoV-2 recombinant vaccine with comprehensive separation techniques to characterize complex heterogeneity.

SARS-CoV-2, the causative agent of COVID-19, has imposed a major public health threat, which needs effective therapeutics and vaccination strategies. Several potential candidate vaccines being rapidly developed are in clinical evaluation and recombinant vaccine has gained much attention thanks to its potential for greater response predictability, improved efficacy, rapid development and reduced side effects. Recombinant vaccines are designed and manufactured using bacterial, yeast cells or mammalian cells.

Using capillary electrophoresis sodium dodecyl sulfate (CE-SDS) and liquid chromatograph mass spectrometry (LC-MS) to identify glycosylated heavy chain heterogeneity in the anti-VEGFR-2 monoclonal antibody.

The size variant, which can be measured by capillary electrophoresis sodium dodecyl sulfate (CE-SDS), is a critical quality attribute of monoclonal antibodies (mAbs). The CE-SDS size heterogeneity can hardly be identified by tandem mass spectrometry, which is an intractable obstacle of mAb development and quality control across the industry. We analyzed the purity of an anti-vascular endothelial growth factor receptor 2 (VEGFR-2) mAb, an antagonist of the human VEGFR-2, through reduced CE-SDS and observed glycosylated heavy chain heterogeneity.

Human rotavirus strains circulating among children in the capital of China (2018-2022)_ predominance of G9P[8] and emergence ofG8P[8].

Objective: This study aimed to update the genetic diversity of Rotavirus (RV) infections in children under five years old in Beijing, China.

Methods: A 5-year active hospital-based surveillance for sporadic acute gastroenteritis (AGE) from January 2018 to December 2022 in the capital of China was performed. A total of 748 fecal samples from AGE patients were collected for followed by RV antigen detection by ELSIA, RNA detection by reverse transcription PCR, G/P genotyping and phylogenetic analyzing.

Genotypes Diversity of Acute Gastroenteritis Outbreaks Caused by Human Sapovirus - Beijing Municipality, China, 2015-2021.

Introduction: Human sapovirus (HuSaV) is an enteric virus responsible for sporadic cases and outbreaks of acute gastroenteritis (AGE) globally. A seven-year active surveillance study was conducted to investigate the molecular epidemiology of HuSaVs associated with AGE outbreaks in Chaoyang District of Beijing Municipality, China from January 2015 to December 2021.

Methods: Fecal and anal swab samples were obtained from patients experiencing AGE outbreaks.

Establishing a novel and sensitive assay for bioactivity determination of anti-CD25 antibodies.

Anti-CD25 antibodies have been approved for renal transplantation and has been used prior to and during transplantation by the Food and Drug Administration (FDA). However, no reported bioassays have been reflected the mechanism of action (MOA) of anti-CD25 antibodies. Here, we describe the development and validation of a reporter gene assay (RGA) based on the engineered C8166-STAT5RE-Luc cells expressing endogenous IL-2 receptors and a STAT5-inducible element-driven firefly luciferase in C8166 cell lines.

Method validation of a bridging immunoassay in combination with acid-dissociation and bead treatment for detection of anti-drug antibody.

Anti-drug antibody (ADA) positivity is correlated with disease relapse risk when treated with monoclonal antibody (mAb) therapeutics. ADA evaluation can assist with interpreting pharmacokinetic, pharmacological, and toxicology results. Here, we established an ADA assay based on two steps of acid dissociation combined with a bridging immunoassay to provide a comprehensive validation strategy.

Mass Spectrometry-Based Charge Heterogeneity Characterization of Therapeutic mAbs with Imaged Capillary Isoelectric Focusing and Ion-Exchange Chromatography as Separation Techniques.

Imaged capillary isoelectric focusing (icIEF) and ion-exchange chromatography (IEX) are two essential techniques that are routinely used for charge variant analysis of therapeutic monoclonal antibodies (mAbs) during their development and in quality control. These two techniques that separate mAb charge variants based on different mechanisms and IEX have been developed as front-end separation techniques for online mass spectrometry (MS) detection, which is robust for intact protein identification. Recently, an innovative, coupled icIEF-MS technology has been constructed for protein charge variant analysis in our laboratory.

Fingerprinting trimeric SARS-CoV-2 RBD by capillary isoelectric focusing with whole-column imaging detection.

Because the spike (S) protein of the severe acute respiratory syndrome coronavirus (SARS-CoV) is the immunodominant antigen, the S protein and its receptor-binding domain (RBD) are both targets currently to be genetically engineered for designing the broad-spectrum vaccine. In theory, the expressed protein exists as a set of variants that are roughly the same but slightly different, which depends on the protein expression system. The variants can be phenotypically manifested as charge heterogeneity.

Development of a reporter gene assay for antibody dependent cellular cytotoxicity activity determination of anti-rabies virus glycoprotein antibodies.

Rabies is a viral disease that is nearly 100% fatal once clinical signs and symptoms develop. Post-exposure prophylaxis can efficiently prevent rabies, and antibody (Ab) induction by vaccination or passive immunization of human rabies immunoglobulin (HRIG) or monoclonal antibodies (mAbs) play an integral role in prevention against rabies. In addition to their capacity to neutralize viruses, antibodies exert their antiviral effects by antibody-dependent cellular cytotoxicity (ADCC), which plays an important role in antiviral immunity and clearance of viral infections.

Efficacy, safety and immunogenicity of hexavalent rotavirus vaccine in Chinese infants.

A randomized, double-blind, placebo-controlled multicenter trial was conducted in healthy Chinese infants to assess the efficacy and safety of a hexavalent live human-bovine reassortant rotavirus vaccine (HRV) against rotavirus gastroenteritis (RVGE). A total of 6400 participants aged 6-12 weeks were enrolled and randomly assigned to either HRV (n ​= ​3200) or placebo (n ​= ​3200) group. All the subjects received three oral doses of vaccine four weeks apart.

Finger printing human norovirus-like particles by capillary isoelectric focusing with whole column imaging detection.

Owing to the limitation of in vitro culture of human noroviruses (HuNoVs), the development of HuNoV vaccines has to depend on the self-assembling virus-like particles (VLPs) with capsid protein expression. The heterogeneity of artificial VLPs exert an impact on the immunogenicity, and should be considered as one of the factors in vaccine evaluation. In this study, we biochemically finger print the HuNoV VLPs with different genogroups, genotypes and sub-genotypes which constitute for a candidate vaccine, by using capillary isoelectric focusing with whole column imaging detection (cIEF-WCID).

Quality comparability assessment of a SARS-CoV-2-neutralizing antibody across transient, mini-pool-derived and single-clone CHO cells.

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has triggered a serious public health crisis worldwide, and considering the novelty of the disease, preventative and therapeutic measures alike are urgently needed. To accelerate such efforts, the development of JS016, a neutralizing monoclonal antibody directed against the SARS-CoV-2 spike protein, was expedited from a typical 12- to 18-month period to a 4-month period. During this process, transient Chinese hamster ovary cell lines are used to support preclinical, investigational new drug-enabling toxicology research, and early Chemistry, Manufacturing and Controls development; mini-pool materials to supply Phase 1 clinical trials; and a single-clone working cell bank for late-stage and pivotal clinical trials were successively adopted.

The endemic GII.4 norovirus-like-particle induced-antibody lacks of cross-reactivity against the epidemic GII.17 strain.

Norovirus-like particle (VLP) vaccine is promising against human norovirus infection. Unfortunately, genetic diversity of norovirus hindered the development of this vaccine. In this study, the immunogenicity of norovirus VLPs induced by the endemic GII.

Efficacy, immunogenicity and safety of a trivalent live human-lamb reassortant rotavirus vaccine (LLR3) in healthy Chinese infants: A randomized, double-blind, placebo-controlled trial.

Background: A randomized, double-blind, placebo-controlled multicenter trial was conducted in healthy Chinese infants to assess the efficacy, immunogenicity and safety of a novel trivalent live human-lamb reassortant rotavirus vaccine (LLR3) against rotavirus gastroenteritis (RVGE).

Methods: Healthy children aged 6-13 weeks were enrolled and randomized (1:1) to either 3 oral doses of LLR3 or placebo according to a 0, 1, 2 month schedule. The objectives were to evaluate vaccine efficacy (VE) against RVGE of any-severity, severe RVGE (sRVGE) and inpatient caused by rotavirus serotypes contained in the vaccine and not contained in the vaccine after the third dose.

Association of human leukocyte antigen alleles and supertypes with immunogenicity of oral rotavirus vaccine given to infants in China.

Rotavirus (RV) vaccines show distinct immunogenicity in dozens of clinical trials, which is associated with multiple host and environmental factors. Previous research has demonstrated that the highly polymorphic human leukocyte antigen (HLA) system plays an essential role in regulating immune response to a variety of vaccines. This study aims to investigate the relationship between HLA polymorphisms and immunogenicity of RV vaccine.

Porcine circovirus type 1 was undetected in vaccine but could be cultured in the cell substrate of Lanzhou lamb rotavirus vaccine.

In 2010, Rotarix was found to be contaminated with infectious porcine circovirus type 1 (PCV1). In China, the Lanzhou lamb rotavirus (LLR) vaccine is the only vaccine used to prevent rotavirus disease. From 2006 to September 2014, more than 54 million doses of LLR vaccines have been lot released.

Detailed analysis of BALB/c mice challenged with wild type rotavirus EDIM provide an alternative for infection model of rotavirus.

Mouse is one of the infection animal models for rotavirus. Since the optimal age of mouse sensitive to rotavirus infection thus far has not been unified, we elucidated clinical symptoms, immune responses and pathological changes of mice in different ages after challenged by murine rotavirus wild strain EDIM (Epidemic Diarrhea of Infant Mice) to provide data for the estimation. One-week-old, two-week-old, and three-week-old BALB/c mice were inoculated with EDIM in the challenge dose of 235 ID50, 470 ID50 and 705 ID50 respectively and were compared to mock-infected controls.

Evaluation of oral Lanzhou lamb rotavirus vaccine via passive transfusion with CD4(+)/CD8(+) T lymphocytes.

Lanzhou Lamb derived Rotavirus (RV) Vaccine (namely LLR) for children is only used in China. Since there were no reports on evaluation of LLR, even the data of phase IV clinical trial, we proceed the evaluation of LLR through focusing on T-cell to investigate whether LLR could induce the potential function involving in protection as a vaccine. Four groups of nude mice were transfused with CD4(+)/CD8(+) T-cells isolated from LLR-immunized (primed) and LLR-unimmunized (naïve) mice via intraperitonea (i.