Evaluation of Binding and Neutralizing Antibodies for Inactivated SARS-CoV-2 Vaccine Immunization.

The circulating severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variant presents an ongoing challenge for surveillance and detection. It is important to establish an assay for SARS-CoV-2 antibodies in vaccinated individuals. Numerous studies have demonstrated that binding antibodies (such as S-IgG and N-IgG) and neutralizing antibodies (Nabs) can be detected in vaccinated individuals.

Quantitative Analysis of the Instant and Persistent Inhibition Effects of Maternal Poliovirus Antibodies on the Immune Response in a Phase IV Trial of a Sabin Strain-Based Inactivated Poliovirus Vaccine.

Background: An inactivated poliomyelitis vaccine made from Sabin strains (sIPVs) has widely been used in China since 2015. However, the quantitative data on the instant and persistent inhibition effects of maternal poliovirus antibodies on the immune response to sIPV priming and booster vaccination have not been available yet.

Objective: In this study, we aim to explore and quantify the instant and persistent inhibition effect of maternal poliovirus antibodies on the immune response elicited by sIPV primary and booster vaccination.

Immunogenicity and lot-to-lot consistency of booster shot with Sabin inactivated poliomyelitis vaccine in Chinese children aged 18-24 Months: A phase Ⅳ clinical trial.

Background: There has been no data on the immunogenicity and safety of the 4 booster dose of the sIPV immunization in 18-24 months old children in post-marketing studies of large cohort providing with robust results.

Method: In a phase Ⅳ randomized, double-blinded clinical trial, 1200 participants aged 2 months were immunized with three consecutive doses of sIPV at 2, 3, and 4 months old to complete primary immunization. Out of the 1200 participants, 1129 received the 4 dose of sIPV as booster immunization.

Evaluation of the immunization effectiveness of bOPV booster immunization and IPV revaccination.

To provide a basis for further optimization of the polio sequential immunization schedule, this study evaluated the effectiveness of booster immunization with one dose of bivalent oral poliovirus vaccine (bOPV) at 48 months of age after different primary polio immunization schedules. At 48 months of age, one dose of bOPV was administered, and their poliovirus types 1-3 (PV1, PV2, and PV3, respectively)-specific neutralizing antibody levels were determined. Participants found to be negative for any type of PV-specific neutralizing antibody at 24, 36, or 48 months of age were re-vaccinated with inactivated polio vaccine (IPV).

Immunogenicity and safety of the inactivated enterovirus 71 vaccine administered concomitantly with the measles-rubella vaccine in infants aged 8 months in China: A noninferiority randomized controlled trial.

Background: To evaluate the immunogenicity and safety of simultaneous administration of the enterovirus 71 (EV71) vaccine with the measles and rubella (MR) combined vaccine.

Methods: In this phase 4, randomized, open-label and noninferiority study, a total of 680 infants aged 8 months were enrolled and assigned to the simultaneous administration group (infants received the first dose of EV71 vaccine and MR vaccine on Day 0, and the second dose of EV71 vaccine on Day 28), or the separate administration groups (EV71 group: infants received two doses of EV71 vaccine on Day 0 and Day 28, respectively; MR group: infants received MR vaccine on Day 0). Blood sample was obtained on Day 0 and Day 56 to measure antibody responses to each of the antigens in terms of antibody titer or concentration, respectively.

Immunological evaluation of an inactivated SARS-CoV-2 vaccine in rhesus macaques.

Because of the relatively limited understanding of coronavirus disease 2019 (COVID-19) pathogenesis, immunological analysis for vaccine development is needed. Mice and macaques were immunized with an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine prepared by two inactivators. Various immunological indexes were tested, and viral challenges were performed on day 7 or 150 after booster immunization in monkeys.

The safety and immunogenicity of an inactivated SARS-CoV-2 vaccine in Chinese adults aged 18-59 years: A phase I randomized, double-blinded, controlled trial.

Background: This study examined the safety and immunogenicity of an inactivated SARS-CoV-2 vaccine.

Method: In a phase I randomized, double-blinded, placebo-controlled trial involving 192 healthy adults 18-59 years old, two injections of three doses (50 EU, 100 EU, 150 EU) of an inactivated SARS-CoV-2 vaccine or placebo were administered intramuscularly at a 2- or 4-week interval. The safety and immunogenicity of the vaccine were evaluated.

analysis of two clinical trials to compare the immunogenicity and safety of different polio immunization schedules in Chinese infants.

Background: A comparative analysis of the immunogenicity and safety of different poliovirus immunization schedules in Chinese infants is imperative to guide the administration of efficient strategies for the eradication of poliomyelitis.

Methods: A analysis was conducted with the data from two poliovirus vaccine clinical trials involving a combined total of 2,400 infants aged 60-90 days. Trivalent oral poliovirus vaccine (tOPV), bivalent oral poliovirus vaccine (bOPV), Sabin strain-based inactivated poliovirus vaccine (sIPV), and conventional inactivated poliovirus vaccine (cIPV) were used in different schedules, the immunogenicity and safety of which were compared 28 days after the last of three doses.

A novel DNA and protein combination COVID-19 vaccine formulation provides full protection against SARS-CoV-2 in rhesus macaques.

The current study aims to develop a safe and highly immunogenic COVID-19 vaccine. The novel combination of a DNA vaccine encoding the full-length Spike (S) protein of SARS-CoV-2 and a recombinant S1 protein vaccine induced high level neutralizing antibody and T cell immune responses in both small and large animal models. More significantly, the co-delivery of DNA and protein components at the same time elicited full protection against intratracheal challenge of SARS-CoV-2 viruses in immunized rhesus macaques.

Immunogenicity and safety of the inactivated poliomyelitis vaccine made from Sabin strains in a phase IV clinical trial for the vaccination of a large population.

As a recently launched novel vaccine used as one of the vaccines for the final eradication of polios worldwide, complete data on the consistency and immunogenicity characteristics of the inactivated poliomyelitis vaccine made from the Sabin strain (sIPV) and its safety in large-scale populations are required to support the future use of this vaccine worldwide. A phase IV clinical trial was conducted to perform an immunogenicity evaluation of lot-to-lot consistency of three commercial batches of sIPV in 1200 infants and to investigate the vaccine's safety on a large-scale in 20,019 infants for active monitoring and 29,683 infants for passive monitoring through the Adverse Event Following Immunization (AEFI) reporting system in China. In the immunogenicity evaluation, the average seroconversion rates for type I, type II and type III of the three groups were 99.

Randomized, Double-Blinded, Placebo-Controlled Phase 2 Trial of an Inactivated Severe Acute Respiratory Syndrome Coronavirus 2 Vaccine in Healthy Adults.

Background: We evaluated an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine for immunogenicity and safety in adults aged 18-59 years.

Methods: In this randomized, double-blinded, controlled trial, healthy adults received a medium dose (MD) or a high dose (HD) of the vaccine at an interval of either 14 days or 28 days. Neutralizing antibody (NAb) and anti-S and anti-N antibodies were detected at different times, and adverse reactions were monitored for 28 days after full immunization.

Potency of the Sabin inactivated poliovirus vaccine (sIPV) after exposure to freezing temperatures in cold chains.

With more demand for Sabin inactivated poliovirus vaccines (sIPVs) to support the global polio eradication effort worldwide, data regarding the potency characteristics of sIPV after exposure to freezing temperatures are urgently required. In the present study, the sIPVs were stored at -20°C for 24 h, 1 week, and 2 weeks in the freezer or in a vaccine carrier for 1 or 3 freeze-thaw cycle to evaluate the effect mediated by freezing temperatures that may be encountered during routine storage and transfer. The potency was then determined by a D-antigen enzyme-linked immunosorbent assay, and the potency was evaluated in Wistar rats.

Effectiveness and Safety of an Inactivated Enterovirus 71 Vaccine in Children Aged 6-71 Months in a Phase IV Study.

Background: Evaluation of a licensed inactivated enterovirus type 71 (EV71) vaccine is needed in a phase IV study with a large population to identify its effectiveness and safety for further application.

Methods: An open-label, controlled trial involving a large population of 155 995 children aged 6-71 months was performed; 40 724 were enrolled in the vaccine group and received 2 doses of inactivated EV71 vaccine at an interval of 1 month, and the remaining children were used as the control group. The EV71-infected cases with hand, foot, and mouth disease were monitored in the vaccine and control groups during a follow-up period of 14 months since the 28th day postinoculation through the local database of the Notifiable Infectious Diseases Network.

The art of partnerships for vaccines.

The Developing Countries Vaccine Manufacturers Network (DCVMN) convened vaccine manufacturing experts and leaders from local and global public health organizations for its 19th Annual General Meeting. Lectures and panel discussions centered on international cooperation for better access to vaccines, and partnerships in areas ranging from vaccine research and process development, to clinical studies, regulatory, supply chain and emergency preparedness and response. Global vaccine market trends and changes that will impact vaccine financing and procurement methods were discussed as well as capital sources, including funding, for the development of new or improved vaccines.

[Epidemiological characteristics of mumps in mainland China from 2004 to 2018 and key population for prevention and control].

Objective: To investigate the epidemiological characteristics of mumps in mainland China from 2004 to 2018, and to provide data for the key population for prevention and control of mumps.

Methods: The epidemiological characteristics of mumps were analyzed with reference to the data of the cases of mumps reported in the National Scientific Data Sharing Platform for Population and Health and Disease Prevention and Control Bureau of National Health Commission of the People's Republic of China. Descriptive epidemiology was used to analyze the epidemiological characteristics of mumps.

Immunogenicity and Safety of an F-Genotype Attenuated Mumps Vaccine in Healthy 8- to 24-Month-Old Children.

Background: Mumps vaccine immunizations have reduced the incidence of this disease. With the variation of mumps circulating strain, novel vaccine strains are always important.

Methods: A 2-center parallel, randomized, double-blind noninferiority trial was performed to compare an F-genotype attenuated mumps vaccine (SP strain) to the A-genotype vaccine (S-79, Jeryl-Lynn strain) in 1080 healthy children aged 8-24 months in Hubei, China.

RNA gene profile variation in peripheral blood mononuclear cells from rhesus macaques immunized with Hib conjugate vaccine, Hib capsular polysaccharide and TT carrier protein.

Background: The Haemophilus influenzae type b (Hib) conjugate vaccine has been widely used in children to prevent invasive Hib disease because of its strong immunogenicity and antibody response induction relative to the capsular polysaccharide (CPS) antigen. The data from vaccine studies suggest that the conjugate vaccine contains carrier proteins that enhance and/or regulate the antigen's immunogenicity, but the mechanism of this enhancement remains unclear.

Methods: To explore the immunological role of the conjugate vaccine, we compared the immune responses and gene profiles of rhesus macaques after immunization with CPS, carrier protein tetanus toxoid (TT) or conjugate vaccine.

Immune Serum From Sabin Inactivated Poliovirus Vaccine Immunization Neutralizes Multiple Individual Wild and Vaccine-Derived Polioviruses.

Background: A Sabin strain-based inactivated poliomyelitis vaccine (Sabin-IPV) is the rational option for completely eradicating poliovirus transmission. The neutralizing capacity of Sabin-IPV immune serum to different strains of poliovirus is a key indicator of the clinical protective efficacy of this vaccine.

Methods: Sera collected from 500 infants enrolled in a randomized, blinded, positive control, phase 2 clinical trial were randomly divided into 5 groups: Groups A, B, and C received high, medium, and low doses, respectively, of Sabin-IPV, while groups D and E received trivalent oral polio vaccine and Salk strain-based IPV, respectively, all on the same schedule.

The Preferential Infection of Astrocytes by Enterovirus 71 Plays a Key Role in the Viral Neurogenic Pathogenesis.

The pathological manifestations of fatal cases of human hand, foot, and mouth disease (HFMD) caused by enterovirus 71 (EV71) are characterized by inflammatory damage to the central nervous system (CNS). Here, the dynamic distribution of EV71 in the CNS and the subsequent pathological characteristics within different regions of neonatal rhesus macaque brain tissue were studied using a chimeric EV71 expressing green fluorescence protein. The results were compared with brain tissue obtained from the autopsies of deceased EV71-infected HFMD patients.

Pathologic and immunologic characteristics of coxsackievirus A16 infection in rhesus macaques.

Coxsackievirus A16 (CV-A16) causes human hand, foot and mouth disease, but its pathogenesis is unclear. In rhesus macaques, CV-A16 infection causes characteristic vesicles in the oral mucosa and limbs as well as viremia and positive viral loads in the tissues, suggesting that these animals reflect the pathologic process of the infection. An immunologic analysis indicated a defective immune response, which included undetectable neutralizing antibodies and IFN-γ-specific memory T-cells in macaques infected with CV-A16.

Phase 3 Trial of a Sabin Strain-Based Inactivated Poliovirus Vaccine.

Background:  The development of a Sabin strain-based inactivated poliovirus vaccine (Sabin-IPV) is imperative to protecting against vaccine-associated paralytic poliomyelitis in developing countries.

Methods:  In this double-blinded, parallel-group, noninferiority trial, eligible infants aged 60-90 days were randomly assigned in a ratio of 1:1 to receive either 3 doses of Sabin-IPV or Salk strain-based IPV (Salk-IPV) at 30-day intervals and a booster at the age of 18 months. Immunogenicity and safety were assessed on the basis of a protocol.

The mutated tegument protein UL7 attenuates the virulence of herpes simplex virus 1 by reducing the modulation of α-4 gene transcription.

Background: UL7, a tegument protein of Herpes Simplex Virus type I (HSV-1), is highly conserved in viral infection and proliferation and has an unknown mechanism of action.

Methods: A HSV-1 UL7 mutant (UL7-MU) was constructed using the CRISPR-cas9 system. The replication rate and plaque morphology were used to analyze the biological characteristics of the wild-type (WT), UL7-MU and MU-complemented P1 viruses.

HSV-1 tegument protein and the development of its genome editing technology.

Herpes simplex virus 1 (HSV-1) is composed of complex structures primarily characterized by four elements: the nucleus, capsid, tegument and envelope. The tegument is an important viral component mainly distributed in the spaces between the capsid and the envelope. The development of viral genome editing technologies, such as the identification of temperature-sensitive mutations, homologous recombination, bacterial artificial chromosome, and the CRISPR/Cas9 system, has been shown to largely contribute to the rapid promotion of studies on the HSV-1 tegument protein.