The seroprevalence of neutralizing antibody against Japanese encephalitis virus in health care workers

ABSTRACTTo maintain immunity against Japanese encephalitis virus (JEV), a formalin-inactivated Japanese encephalitis (JE) vaccine should be administered several times. The repeated vaccination is not helpful in the case of a sudden outbreak of JEV or when urgent travel to a high-JEV-risk region is required; however, there are few single-injection JE vaccine options. In the present study, we investigated the efficacy of a single dose of a new effective JE virus-like particle preparation containing the JE envelope protein (JE-VLP). Although single administration with JE-VLP protected less than 50% of mice against lethal JEV infection, adding poly(γ-glutamic acid) nanoparticles (γ-PGA-NPs) or aluminum adjuvant (alum) to JE-VLP significantly protected more than 90% of the mice. A single injection of JE-VLP with either γ-PGA-NPs or alum induced a significantly greater anti-JEV neutralizing antibody titer than JE-VLP alone. The enhanced titers were maintained for more than 6 months, resulting in long-lasting protection of 90% of the immunized mice. Although the vaccine design needs further modification to reach 100% protection, a single dose of JE-VLP with γ-PGA-NPs may be a useful step in developing a next-generation vaccine to stop a JE outbreak or to immunize travelers or military personnel.

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Detection of antibodies to Japanese encephalitis virus in the wild boars in Hiroshima prefecture, Japan

Epidemiology and Infection ◽

10.1017/s0950268806007710 ◽

2007 ◽

Vol 135 (6) ◽

pp. 974-977 ◽

Cited By ~ 25

Author(s):

M. HAMANO ◽

C. K. LIM ◽

H. TAKAGI ◽

K. SAWABE ◽

M. KUWAYAMA ◽

...

Keyword(s):

Japanese Encephalitis Virus ◽

Japanese Encephalitis ◽

Neutralization Test ◽

Neutralizing Antibody ◽

Encephalitis Virus ◽

Western Region ◽

Wild Boars ◽

In The Wild ◽

Hiroshima Prefecture ◽

Infectious Cycle

SUMMARYSerum specimens were collected from 25 wild boars in Hiroshima prefecture located in the western region of Japan from November 2004 to February 2005. The sera were tested for antibodies to Japanese encephalitis virus (JEV) by IgM capture and IgG enzyme-linked immunosorbent assays (ELISA), and plaque reduction neutralization test. Seventeen samples (68%) were positive for neutralizing antibody to JEV. All the neutralizing antibody-positive samples were positive for IgG-ELISA. One was also positive for IgM. The results indicate that approximately 70% of the wild boars were positive for anti-JEV antibody, and raises the possibility that wild boars may play a role in the infectious cycle of JEV in this region.

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Reduced neutralizing antibody titer against genotype I virus in swine immunized with a live-attenuated genotype III Japanese encephalitis virus vaccine

Veterinary Microbiology ◽

10.1016/j.vetmic.2013.01.017 ◽

2013 ◽

Vol 163 (3-4) ◽

pp. 248-256 ◽

Cited By ~ 14

Author(s):

Yi-Chin Fan ◽

Jo-Mei Chen ◽

Yi-Ying Chen ◽

Jen-Wei Lin ◽

Shyan-Song Chiou

Keyword(s):

Japanese Encephalitis Virus ◽

Antibody Titer ◽

Japanese Encephalitis ◽

Virus Vaccine ◽

Neutralizing Antibody ◽

Encephalitis Virus ◽

Genotype I ◽

Genotype Iii

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Neutralizing antibody against SARS-CoV-2 spike in COVID-19 patients, health care workers and convalescent plasma donors: a cohort study using a rapid and sensitive high-throughput neutralization assay

10.1101/2020.08.02.20166819 ◽

2020 ◽

Cited By ~ 3

Author(s):

Cong Zeng ◽

John P Evans ◽

Rebecca Pearson ◽

Panke Qu ◽

Yi-Min Zheng ◽

...

Keyword(s):

Health Care ◽

High Throughput ◽

Health Care Workers ◽

Neutralizing Antibody ◽

Neutralization Assay ◽

Luciferase Reporter ◽

Human Antibody ◽

Icu Patients ◽

Care Workers ◽

Antibody Titers

Rapid and specific antibody testing is crucial for improved understanding, control, and treatment of COVID-19 pathogenesis. Herein, we describe and apply a rapid, sensitive, and accurate virus neutralization assay for SARS-CoV-2 antibodies. The new assay is based on an HIV-1 lentiviral vector that contains a secreted intron Gaussia luciferase or secreted Nano-luciferase reporter cassette, pseudotyped with the SARS-CoV-2 spike (S) glycoprotein, and is validated with a plaque reduction assay using an authentic, infectious SARS-CoV-2 strain. The new assay was used to evaluate SARS-CoV-2 antibodies in serum from individuals with a broad range of COVID-19 symptoms, including intensive care unit (ICU) patients, health care workers (HCWs), and convalescent plasma donors. The highest neutralizing antibody titers were observed among ICU patients, followed by general hospitalized patients, HCWs and convalescent plasma donors. Our study highlights a wide phenotypic variation in human antibody responses against SARS-CoV-2, and demonstrates the efficacy of a novel lentivirus pseudotype assay for high-throughput serological surveys of neutralizing antibody titers in large cohorts.

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Complete protection for mice conferred by a DNA vaccine based on Japanese encephalitis virus P3 strain that is used to prepare the inactivated vaccine in China

10.21203/rs.2.20138/v1 ◽

2020 ◽

Author(s):

Ran Wang ◽

Xiaozheng Yu ◽

Yan Wang ◽

Xiaoyan Zheng

Keyword(s):

Japanese Encephalitis Virus ◽

Dna Vaccine ◽

Japanese Encephalitis ◽

Protective Efficacy ◽

Neutralizing Antibody ◽

Encephalitis Virus ◽

Inactivated Vaccine ◽

Complete Protection ◽

Igg Antibody ◽

Humoral Immune

Abstract Background The incidence of Japanese encephalitis (JE) has been dramatically reduced in China after the coverage of the vaccine. It is believed that the live-attenuated Japanese encephalitis virus (JEV) vaccine SA14-14-2 has contributed a lot. Another vaccine that seems to have faded out of the public is an inactivated vaccine based on the JEV P3 strain, which is still considered to have certain modifiability, such as being transformed into a DNA vaccine to improve its immunogenicity. Methods In this study, the protective efficacy induced by a Japanese encephalitis DNA vaccine candidate pV-JP3ME encoding pre-membrane (prM) and envelope (E) proteins of P3 strain in BALB/c mice. The prM/E genes of the JEV P3 strain were subcloned into vector pVAX1 (pV) to construct pV-JP3ME. Results The plasmid DNA was immunized BALB/c mice, high titers of IgG antibody and neutralizing antibody (nAb) against JEV were detected. The key cytokines in splenocytes upon stimulation with JEV antigens were secreted. Finally, complete protective efficacy was generated after challenge with the JEV P3 strain in mice. Conclusions The DNA vaccine pV-JP3ME based on JEV P3 strain in this study can induce specific humoral immune and cytokine responses in mice, and provide complete protection for mice against JEV.

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BNT162b2 SARS-CoV-2 Vaccination Elicits High Titers of Neutralizing Antibodies to Both B.1 and P.1 Variants in Previously Infected and Uninfected Subjects

Life ◽

10.3390/life11090896 ◽

2021 ◽

Vol 11 (9) ◽

pp. 896

Author(s):

Ilaria Vicenti ◽

Francesca Gatti ◽

Renzo Scaggiante ◽

Adele Boccuto ◽

Daniela Zago ◽

...

Keyword(s):

Health Care ◽

Health Care Workers ◽

Neutralizing Antibodies ◽

Vaccine Dose ◽

Neutralizing Antibody ◽

Post Vaccination ◽

Care Workers ◽

Antibody Titers ◽

Cross Neutralization ◽

Highly Correlated

We aimed to investigate neutralizing antibody titers (NtAbT) to the P.1 and B.1 SARS-CoV-2 variants in a cohort of healthy health care workers (HCW), including 20 previously infected individuals tested at baseline (BLinf, after a median of 298 days from diagnosis) and 21 days after receiving one vaccine dose (D1inf) and 15 uninfected subjects tested 21 days after the second-dose vaccination (D2uninf). All the subjects received BNT162b2 vaccination. D1inf NtAbT increased significantly with respect to BLinf against both B.1 and P.1 variants, with a fold-change significantly higher for P.1. D1inf NtAbT were significantly higher than D2uninf NtAbT, against B.1 and P.1. NtAbT against the two strains were highly correlated. P.1 NtAbT were significantly higher than B.1 NtAbT. This difference was significant for post-vaccination sera in infected and uninfected subjects. A single-dose BNT162b2 vaccination substantially boosted the NtAb response to both variants in the previously infected subjects. NtAb titers to B.1 and P.1 lineages were highly correlated, suggesting substantial cross-neutralization. Higher titers to the P.1 than to the B.1 strain were driven by the post-vaccination titers, highlighting that cross-neutralization can be enhanced by vaccination.

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