Efficacy of the H7N9 vaccine as a candidate for the Korean avian influenza antigen bank.

The avian influenza A virus (H7N9), first detected in China in 2013, is a zoonotic virus that remains persistent in bird populations despite a decline in human cases owing to control measures. Therefore, this study aimed to develop a vaccine as one preventive strategy in anticipation of the potential entry of H7N9 into Korea. Using the hemagglutinin and neuraminidase consensus sequences of H7N9 from 2018-2019, a recombinant H7N9 vaccine, rgAPQAH7N9, was developed, and its protective efficacy in specific pathogen-free chickens was evaluated.

Protective efficacy of a bivalent H5 influenza vaccine candidate against both clades 2.3.2.1 and 2.3.4.4 high pathogenic avian influenza viruses in SPF chickens.

Worldwide, high pathogenic avian influenza viruses belonging to clades 2.3.4.

Protection of SPF Chickens by H9N2 Y439 and G1 Lineage Vaccine against Homologous and Heterologous Viruses.

Prior to the identification of low pathogenic avian influenza H9N2 viruses belonging to the Y280 lineage in 2020, Y439 lineage viruses had been circulating in the Republic of Korea since 1996. Here, we developed a whole inactivated vaccine (vac564) by multiple passage of Y439 lineage viruses and then evaluated immunogenicity and protective efficacy in specific-pathogen-free chickens. We found that LBM564 could be produced at high yield in eggs (10EID/0.

Updating the National Antigen Bank in Korea: Protective Efficacy of Synthetic Vaccine Candidates against H5Nx Highly Pathogenic Avian Influenza Viruses Belonging to Clades 2.3.2.1 and 2.3.4.4.

Since 2018, Korea has been building an avian influenza (AI) national antigen bank for emergency preparedness; this antigen bank is updated every 2 years. To update the vaccine strains in the antigen bank, we used reverse genetics technology to develop two vaccine candidates against avian influenza strains belonging to clades 2.3.

Emergence of clade 2.3.4.4b novel reassortant H5N1 high pathogenicity avian influenza virus in South Korea during late 2021.

High pathogenicity H5N1 avian influenza viruses pose a threat to both animal and human health worldwide. In late 2020, outbreaks of H5 high pathogenicity avian influenza viruses belonging to clade 2.3.

Cross-protective efficacy of inactivated whole influenza vaccines against Korean Y280 and Y439 lineage H9N2 viruses in mice.

Since June 2020, the Y280 lineage H9N2 virus, which is distinct from the previously endemic Y439 lineage, has been circulating in poultry in Korea. In this study, we developed two whole inactivated vaccines, rgHS314 and vac564, against the Y280 and Y439 lineages, respectively, and evaluated their immunogenicity and protective efficacy against homologous or heterologous viral challenge in mice. Serum neutralizing antibody titers in the rgHS314-vaccinated group were higher (68 ± 8.

Development of a recombinant H9N2 influenza vaccine candidate against the Y280 lineage field virus and its protective efficacy.

Since June 2020, a new H9N2 virus of the Y280 lineage has been epidemic in Korea. Initially, a Korean commercial vaccine against the Y280 and Y439 lineages of H9N2 was evaluated for use in SPF chickens. A single vaccination did not protect chickens against virus of the Y280 lineage, with no significant reduction in virus shedding and a 37.

Single dose of multi-clade virus-like particle vaccine protects chickens against clade 2.3.2.1 and clade 2.3.4.4 highly pathogenic avian influenza viruses.

Virus-like particles (VLPs) are recognized as an alternative vaccine platform that provide effective protection against various highly pathogenic avian influenza viruses (HPAIVs). Here, we developed multi-clade VLPs expressing two HAs (a chimera of clade 2.3.

Efficient distribution of oral vaccines examined by infrared triggered camera for advancing the control of raccoon dog rabies in South Korea.

The field distribution of the oral rabies vaccine is effective in controlling the spread of rabies. The present study aimed to investigate efficient distribution locations based on the environment, contact rate, and consumption by target wildlife species in South Korea. The target species (Korean raccoon dogs, domestic dogs, and feral cats) accounted for 945 contacts (52.

Protection of layers and breeders against homologous or heterologous HPAIv by vaccines from Korean national antigen bank.

Korean government has selected and stocked five type antigens of two clades as Korean national antigen bank having high possibility of introduction to Korea. We aimed to evaluate the efficacy of the clade 2.3.

Sales and immunogenicity of commercial vaccines to H9N2 low pathogenic avian influenza virus in Korea from 2007 to 2017.

The present study was conducted to monitor sales activity and immunogenicity of commercial H9N2 vaccines produced in Korea from 2007 to 2017. Recorded sales of H9N2 vaccine were around 671 million doses, with 10 million doses sold in 2007, rising to a peak of 93 million doses in 2016, with a slight fall in 2017. Multivalent combined vaccines made up around 90% of all vaccine sales, and around 30% of all vaccines were distributed by regional governments for free.

Protective efficacy of vaccines of the Korea national antigen bank against the homologous H5Nx clade 2.3.2.1 and clade 2.3.4.4 highly pathogenic avian influenza viruses.

The occurrence of severe outbreaks of highly pathogenic avian influenza in Korea led to establishment of a national antigen bank for emergency preparedness. Here, we developed five vaccines for this bank (clade 2.3.

Novel reassortants of clade 2.3.4.4 H5N6 highly pathogenic avian influenza viruses possessing genetic heterogeneity in South Korea in late 2017.

Novel H5N6 highly pathogenic avian influenza viruses (HPAIVs) were isolated from duck farms and migratory bird habitats in South Korea in November to December 2017. Genetic analysis demonstrated that at least two genotypes of H5N6 were generated through reassortment between clade 2.3.

Total synthesis of (±)-lycorine from the endo-cycloadduct of 3,5-dibromo-2-pyrone and (E)-β-borylstyrene.

A new synthetic route to (±)-lycorine, starting from the endo-cycloadduct of 3,5-dibromo-2-pyrone and (E)-β-borylstyrene, is reported. Boronate oxidation and a set of reactions including face-selective epoxidation provided the pivotal C1-OH group and C3/C3a double bond.

(E)-β-borylstyrene in the Diels-Alder reaction with 3,5-dibromo-2-pyrone for the syntheses of (±)-1-epi-pancratistatin and (±)- pancratistatin.

New synthetic routes to (±)-1-epi-pancratistatin and (±)-pancratistatin were devised using (E)-β-borylstyrene as a dienophile for the key Diels-Alder reaction with 3,5-dibromo-2-pyrone. The boronate in the cycloadduct was oxidized to provide the pivotal C1-hydroxyl group of the titled compounds.

Total syntheses of (±)-α-lycorane and (±)-1-deoxylycorine.

New synthetic routes to (±)-α-lycorane and (±)-1-deoxylycorine were exploited. The endo-cycloadduct of 3,5-dibromo-2-pyrone with styrene-type dienophile provided the pivotal intermediate for the syntheses of the titled natural products.

β-Silyl styrene as a dienophile in the cycloaddition with 3,5-dibromo-2-pyrone for the total synthesis of (±)-pancratistatin.

A new synthetic route to (±)-pancratistatin was devised utilizing β-silyl styrene as a dienophile in the cycloaddition with 3,5-dibromo-2-pyrone. The TMS group incorporated in the cycloadduct permitted a facile elimination process for the eventual installation of the C(1)-OH function. Subsequent transformations including Curtius rearrangement and Bischler-Napieralski reactions completed the total synthesis of (±)-pancratistatin.

Minimum-step immuno-analysis based on continuous recycling of the capture antibody.

Most immuno-analytical systems employ antibodies that do not readily dissociate upon binding to its partner antigen (i.e., target analyte; α2-macroglobulin as a model) and, thus, either need to be disposed of after one-time use or be reused after binding has been reset.

An ELISA-on-a-chip biosensor system coupled with immunomagnetic separation for the detection of Vibrio parahaemolyticus within a single working day.

In this study, we constructed a rapid detection system for a foodborne pathogen, Vibrio parahaemolyticus, by using enzyme-linked immunosorbent assay (ELISA)-on-a-chip (EOC) biosensor technology to minimize the risk of infection by the microorganism. The EOC results showed a detection capability of approximately 6.2x10(5) cells per ml, which was significantly higher than that of the conventional rapid test kit.