المؤلفون: Wang-Da Liu, Jann-Tay Wang, Tai-Ling Chao, Si-Man Ieong, Ya-Min Tsai, Po-Hsien Kuo, Ming-Jui Tsai, Yi-Jie Chen, Guei-Chi Li, Shu-Yuan Ho, Hui-Hou Chen, Yu-Shan Huang, Chien-Ching Hung, Yee-Chun Chen, Sui-Yuan Chang, Shan-Chwen Chang

المصدر: Journal of the Formosan Medical Association, Vol 122, Iss 8, Pp 714-722 (2023)

مصطلحات موضوعية: Plaque reduction neutralization test (PRNT), Humoral immunity, Spike protein, Variant of concern, Delta variant, B.1.617.2, Medicine (General), R5-920

الوصف: Background: Patients recovering from COVID-19 may need vaccination against SARS-CoV-2 because acquired immunity from primary infection may wane, given the emergence of new SARS-CoV-2 variants. Understanding the trends of anti-spike IgG and neutralizing antibody titers in patients recovering from COVID-19 may inform the decision made on the appropriate interval between recovery and vaccination. Methods: Participants aged 20 years or older and diagnosed with COVID-19 between January and December, 2020 were enrolled. Serum specimens were collected every three months from 10 days to 12 months after the onset of symptom for determinations of anti-spike IgG and neutralizing antibody titers against SARS-CoV-2 Wuhan strain with D614G mutation, alpha, gamma and delta variants. Results: Of 19 participants, we found a decreasing trend of geometric mean titers of anti-spike IgG from 560.9 to 217 and 92 BAU/mL after a 4-month and a 7-month follow-up, respectively. The anti-spike IgG titers declined more quickly in the ten participants with severe or critical disease than the nine participants with only mild to moderate disease between one month and seven months after SARS-CoV-2 infection (−8.49 vs - 2.34-fold, p

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S0929664622004363Test; https://doaj.org/toc/0929-6646Test

الوصول الحر: https://doaj.org/article/4bc0e23eccf9454b8fa54efd270cdfb7Test

المؤلفون: John Merluza, Johnny Ung, Kai Makowski, Alyssia Robinson, Kathy Manguiat, Nicole Mueller, Jonathan Audet, Julie Chih-Yu Chen, James E. Strong, Heidi Wood, Alexander Bello

المصدر: Microbiology Spectrum, Vol 11, Iss 1 (2023)

مصطلحات موضوعية: plaque reduction neutralization test, SARS-CoV-2 lentivirus surrogate neutralization assay, validation, Microbiology, QR1-502

الوصف: ABSTRACT Neutralization assays are important for understanding and quantifying neutralizing antibody responses toward severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 lentivirus surrogate neutralization assay (SCLSNA) can be used in biosafety level 2 (BSL-2) laboratories and has been shown to be a reliable alternative approach to the plaque reduction neutralization test (PRNT). In this study, we optimized and validated the SCLSNA to assess its ability as a comparator and prescreening method to support the PRNT. Comparability between the PRNT and SCLSNA was determined through clinical sensitivity and specificity evaluations. Clinical sensitivity and specificity assays produced acceptable results, with 100% (95% confidence interval [CI], 94% to 100%) specificity and 100% (95% CI, 94% to 100%) sensitivity against ancestral Wuhan spike-pseudotyped lentivirus. The sensitivity and specificity against B.1.1.7 spike-pseudotyped lentivirus were 88.3% (95% CI, 77.8% to 94.2%) and 100% (95% CI, 94% to 100%), respectively. Assay precision measuring intra-assay variability produced acceptable results for high (50% PRNT [PRNT50], 1:≥640), mid (PRNT50, 1:160), and low (PRNT50, 1:40) antibody titer concentration ranges based on the PRNT50, with coefficients of variation (CVs) of 14.21%, 12.47%, and 13.28%, respectively. Intermediate precision indicated acceptable ranges for the high and mid concentrations, with CVs of 15.52% and 16.09%, respectively. However, the low concentration did not meet the acceptance criteria, with a CV of 26.42%. Acceptable ranges were found in the robustness evaluation for both intra-assay and interassay variability. In summary, the validation parameters tested met the acceptance criteria, making the SCLSNA method fit for its intended purpose, which can be used to support the PRNT. IMPORTANCE Neutralization studies play an important role in providing guidance and justification for vaccine administration and helping prevent the spread of diseases. The neutralization data generated in our laboratory have been included in the decision-making process of the National Advisory Committee on Immunization (NACI) in Canada. During the coronavirus 2019 (COVID-19) pandemic, the plaque reduction neutralization test (PRNT) has been the gold standard for determining neutralization of SARS-CoV-2. We validated a SARS-CoV-2 lentivirus surrogate neutralization assay (SCLSNA) as an alternative method to help support the PRNT. The advantages of using the SCLSNA is that it can process more samples, is less tedious to perform, and can be used in laboratories with a lower biosafety level. The use of the SCLSNA can further expand our capabilities to help fulfill the requirements for NACI and other important collaborations.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/2165-0497Test

الوصول الحر: https://doaj.org/article/8cd110eb4adb4ed6a093025d51035295Test

المؤلفون: Min Li, Ruiwei Jiang, Enyun Wang, Dan Xiong, Tong Ou, Xiuming Zhang, Xiaowen Dou

المصدر: BMC Infectious Diseases, Vol 22, Iss 1, Pp 1-8 (2022)

مصطلحات موضوعية: SARS-CoV-2 vaccine, Immunoassays, Neutralizing antibodies, Serological assay, Plaque reduction neutralization test, Real world, Infectious and parasitic diseases, RC109-216

الوصف: Abstract Objective Reliable high-throughput serological assays for SARS-CoV-2 antibodies present an important role in the strength and duration of immunity after vaccination. The study investigated the analytical and clinical performances of neutralizing antibodies (NTAb) assay by chemiluminescent (CLIA), and SARS-CoV-2 neutralizing antibody after vaccination in real world. Methods The analytical performances of CLIA for SARS-CoV-2 NTAb were evaluated, followed by the sensitivity and specificity identified with a PRNT test from 50 volunteers. Then, a cohort of vaccine recipients (n = 37) were tracked with SARS-CoV-2 NTAb assay at prior to vaccination, one, three and six months post two doses. In real world, a total of 737 cases were recruited from physical examination center in Shenzhen Luohu People’s Hospital (from Jun to August 2021) to analyze vaccination status. Results Serological assays on the CLIA were found with excellent characteristics including imprecision, repeatability and linearity. Besides, it was robust to icterus, lipemia and hemolysis. The good sensitivity and specificity were obtained at 98% and 100%, respectively. NTAb results showed a high correlation with PRNT50 titers (r 0.61). Until July 2021, the BBIBP-CorV (76.3%) and Sinovac CoronaVac (20.5%) were the predominant vaccines injection in Shenzhen, China. Adolescent less than 18 years was the main unvaccinated group (52.1%). The seropositive rate of inactive SRAR-CoV-2 vaccines exceeded 97% after inoculation. The NTAb generated by Sinovac CoronaVac with the schedule of 0–56 days was found significantly lower than that by BBIBP-CorV (P

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/1471-2334Test

الوصول الحر: https://doaj.org/article/96ba38986b0244ee8453773f5c9dd229Test

المؤلفون: Divya Lakhotia, Yin May Tun, Nanthanida Mongkol, Oranit Likhit, Sarocha Suthisawat, Suthee Mangmee, Daraka Tongthainan, Wirasak Fungfuang, Phitsanu Tulayakul, Kobporn Boonnak

المصدر: Viruses; Volume 15; Issue 5; Pages: 1125

مصطلحات موضوعية: Japanese encephalitis virus, seroprevalence, Plaque Reduction Neutralization Test, Flavivirus

جغرافية الموضوع: agris

الوصف: Japanese encephalitis virus (JEV) is a member of the Flaviviridae family and one of Asia’s most common causes of encephalitis. JEV is a zoonotic virus that is transmitted to humans through the bite of infected mosquitoes of the Culex species. While humans are dead-end hosts for the virus, domestic animals such as pigs and birds are amplification hosts. Although JEV naturally infected monkeys have been reported in Asia, the role of non-human primates (NHPs) in the JEV transmission cycle has not been intensively investigated. In this study, we demonstrated neutralizing antibodies against JEV in NHPs (Macaca fascicularis) and humans living in proximity in two provinces located in western and eastern Thailand by using Plaque Reduction Neutralization Test (PRNT). We found a 14.7% and 5.6% seropositive rate in monkeys and 43.7% and 45.2% seropositive rate in humans living in west and east Thailand, respectively. This study observed a higher seropositivity rate in the older age group in humans. The presence of JEV neutralizing antibodies in NHPs that live in proximity to humans shows the occurrence of natural JEV infection, suggesting the endemic transmission of this virus in NHPs. According to the One Health concept, regular serological studies should be conducted especially at the animal–human interface.

وصف الملف: application/pdf

العلاقة: Animal Viruses; https://dx.doi.org/10.3390/v15051125Test

الإتاحة: https://doi.org/10.3390/v15051125Test

المؤلفون: Sunil R. Vaidya

المصدر: Viruses; Volume 15; Issue 4; Pages: 939

مصطلحات موضوعية: emerging and reemerging viruses, neutralizing antibody, plaque reduction neutralization test, vaccine-preventable viral diseases

جغرافية الموضوع: agris

الوصف: Since their first documentation in 1952, plaque reduction neutralization tests (PRNTs) have become the choice of test for the measurement of neutralizing antibodies against a particular virus. However, PRNTs can be performed only against viruses that cause cytopathic effects (CPE). PRNTs also require skilled personnel and can be time-consuming depending on the time required for the virus to cause CPE. Hence, their application limits large-scale studies or epidemiological and laboratory investigations. Since 1978, many surrogate PRNTs or immunocolorimetric assay (ICA)-based focus reduction neutralization tests (FRNT) have been developed. In this article, ICAs and their utility in FRNTs for the characterization of neutralizing antibodies, homologous or heterologous cross-neutralization, and laboratory diagnosis of viruses of public health importance have been discussed. Additionally, possible advancements and automations have been described that may help in the development and validation of novel surrogate tests for emerging viruses.

وصف الملف: application/pdf

العلاقة: Viral Immunology, Vaccines, and Antivirals; https://dx.doi.org/10.3390/v15040939Test

الإتاحة: https://doi.org/10.3390/v15040939Test

المؤلفون: Mutantu, Nsele Pierre

المصدر: International Journal of Environmental Research and Public Health. 18 18

مصطلحات موضوعية: SARS-CoV-2, nucleocapsid protein, IgG indirect ELISA, plaque reduction neutralization test

وصف الملف: PDF

الوصول الحر: https://ndlsearch.ndl.go.jp/books/R100000039-I12296681Test

Degree: 博士(医学) -- Nagasaki University (長崎大学)

المؤلفون: Nareerat Sangkachai, Somjit Chaiwattanarungruengpaisan, Metawee Thongdee, Parut Suksai, Siriporn Tangsudjai, Peerawat Wongluechai, Sarin Suwanpakdee, Witthawat Wiriyarat, Ruangrat Buddhirongawatr, Luxsana Prasittichai, Anurux Skulpong, Pilailuk Akkapaiboon Okada, Pilaipan Puthavathana, Weena Paungpin

المصدر: Animals, Vol 12, Iss 23, p 3350 (2022)

مصطلحات موضوعية: captive tigers, SARS-CoV-2, plaque reduction neutralization test, surveillance, Thailand, Veterinary medicine, SF600-1100, Zoology, QL1-991

الوصف: Coronavirus disease (COVID-19) is an emerging infectious disease caused by SARS-CoV-2. Given the emergence of SARS-CoV-2 variants, continuous surveillance of SARS-CoV-2 in animals is important. To monitor SARS-CoV-2 infection in wildlife in Thailand, we collected 62 blood samples and nine nasal- and rectal-swab samples from captive tigers (Panthera tigris) in Ratchaburi province in Thailand during 2020–2021. A plaque reduction neutralization test (PRNT) was employed to detect SARS-CoV-2 neutralizing antibodies. A real-time RT-PCR assay was performed to detect SARS-CoV-2 RNA. Our findings demonstrated that four captive tigers (6.5%, 4/62) had SARS-CoV-2 neutralizing antibodies against Wuhan Hu-1 and the Delta variant, while no SARS-CoV-2 RNA genome could be detected in all swab samples. Moreover, a low-level titer of neutralizing antibodies against the Omicron BA.2 subvariant could be found in only one seropositive tiger. The source of SARS-CoV-2 infection in these tigers most likely came from close contact with the infected animals’ caretakers who engaged in activities such as tiger petting and feeding. In summary, we described the first case of natural SARS-CoV-2 infection in captive tigers during the COVID-19 outbreak in Thailand and provided seroepidemiological-based evidence of human-to-animal transmission. Our findings highlight the need for continuous surveillance of COVID-19 among the captive tiger population and emphasize the need to adopt a One Health approach for preventing and controlling outbreaks of COVID-19 zoonotic disease.

وصف الملف: electronic resource

العلاقة: https://www.mdpi.com/2076-2615/12/23/3350Test; https://doaj.org/toc/2076-2615Test

الوصول الحر: https://doaj.org/article/263c9e0cfd2948fea5d381ad595b6ce1Test

المؤلفون: Flávia Löwen Levy Chalhoub, Marco Aurélio Pereira Horta, Luiz Carlos Junior Alcantara, Alejandra Morales, Lilha Maria Barbosa dos Santos, Vinícius Guerra-Campos, Cintia D. S. Rodrigues, Carolina C. Santos, Maria Angélica M. Mares-Guia, Alex Pauvolid-Corrêa, Ana Maria Bispo de Filippis

المصدر: Viruses, Vol 14, Iss 11, p 2459 (2022)

مصطلحات موضوعية: West Nile virus, Saint Louis encephalitis virus, horses, plaque reduction neutralization test, RT-qPCR, Rio de Janeiro, Microbiology, QR1-502

الوصف: Infections with arboviruses are reported worldwide. Saint Louis encephalitis (SLEV) and West Nile viruses (WNV) are closely related flaviviruses affecting humans and animals. SLEV has been sporadically detected in humans, and corresponding antibodies have been frequently detected in horses throughout Brazil. WNV was first reported in western Brazil over a decade ago, has been associated with neurological disorders in humans and equines and its prevalence is increasing nationwide. Herein, we investigated by molecular and serological methods the presence or evidence of SLEV and WNV in equines from Rio de Janeiro. A total of 435 serum samples were collected from healthy horses and tested for specific neutralizing antibodies by plaque reduction neutralization test (PRNT90). Additionally, serum and central nervous system samples from 72 horses, including horses with neurological disorders resulting in a fatal outcome or horses which had contact with them, were tested by real-time reverse transcription–polymerase chain reaction (RT-qPCR) for both viruses. Adopting the criterion of four-fold antibody titer difference, 89 (20.4%) horses presented neutralizing antibodies for SLEV and five (1.1%) for WNV. No evidence of SLEV and WNV infection was detected by RT-qPCR and, thus, such infection could not be confirmed in the additional samples. Our findings indicate that horses from Rio de Janeiro were exposed to both SLEV and WNV, contributing to the current knowledge on the distribution of these viruses flaviviruses in Brazil.

وصف الملف: electronic resource

العلاقة: https://www.mdpi.com/1999-4915/14/11/2459Test; https://doaj.org/toc/1999-4915Test

الوصول الحر: https://doaj.org/article/45fec989f53c4dfcb74b0ed495fe54d7Test

المساهمون: Younhee Park, Ah-Ra Kim, Yun-Ho Hwang, Hyejung Yang, June-Woo Lee, Mi Young Kim, Hwa Su Kim, Gyung Tae Chung, Jung Sik Yoo, You-Jin Kim, Dokeun Kim, Hyeran Won, Park, Youn Hee

مصطلحات موضوعية: Animals, Antibodies, Neutralizing, Viral, Encephalitis Virus, Japanese, Encephalitis Viruses, Encephalitis, Japanese* / diagnosis, Humans, Neutralization Tests / methods, Viral Plaque Assay, Focus reduction neutralization test, Japanese encephalitis virus, Plaque reduction neutralization test

الوصف: Japanese encephalitis is prevalent throughout the temperate and tropical regions of Asia and is caused by the Japanese encephalitis virus (JEV), a mosquito-borne viral pathogen. The plaque reduction neutralization test (PRNT) is currently recommended as the gold standard test for detecting human antibodies against JEV. The plaque assay is the most widely used method for detecting infectious virions and involves counting discrete plaques in cells. However, it is time-consuming, and results can be subjective (owing to analyst variability during manual plaque counting). The focus reduction neutralization test (FRNT), which is based on an immuno-colorimetric assay, can be used to automatically count foci formed by the JEV. Here, we compared the efficacy of PRNT and FRNT in measuring the neutralizing antibody titers using 102 serum samples from vaccinated and unvaccinated individuals. We observed positive correlations between these neutralization assays against the Nakayama and Beijing strains (R2 = 0.98 and 0.77, respectively). Thus, FRNT may be preferable to PRNT for evaluating the efficacy of JEV vaccines in large-scale serological studies. ; open

العلاقة: JOURNAL OF VIROLOGICAL METHODS; J01929; OAK-2022-02409; https://ir.ymlib.yonsei.ac.kr/handle/22282913/189275Test; T202201849; JOURNAL OF VIROLOGICAL METHODS, Vol.306 : 114540, 2022-08

الإتاحة: https://doi.org/10.1016/j.jviromet.2022.114540Test
https://ir.ymlib.yonsei.ac.kr/handle/22282913/189275Test

المؤلفون: Campos, Fabrício Souza, Franco, Ana Claudia, Roehe, Paulo Michel, Abreu, Filipe Vieira Santos de, Oliveira, Danilo Bretas de

مصطلحات موضوعية: Poxviridae, Non-human primates, Vaccinia virus, Plaque reduction neutralization test, Infecções por poxviridae, Orthopoxvirus, Vírus Vaccinia

الوصف: The genus Orthopoxvirus (OPXV) of the family Poxviridae comprises several viruses that are capable of infecting a wide range of hosts. One of the most widespread OPXVs is the Vaccinia virus (VACV), which circulates in zoonotic cycles in South America, especially in Brazil, infecting domestic and wild animals and humans and causing economic losses as well as impacting public health. Despite this, little is known about the presence and/or exposure of neotropical primates to orthopoxviruses in the country. In this study, we report the results of a search for evidence of OPVX infections in neotropical free-living primates in the state of Minas Gerais, southeast Brazil. The sera or liver tissues of 63 neotropical primates were examined through plaque reduction neutralization tests (PRNT) and real-time PCR. OPXV-specific neutralizing antibodies were detected in two sera (4.5%) from Callithrix penicillata, showing 55% and 85% reduction in plaque counts, evidencing their previous exposure to the virus. Both individuals were collected in urban areas. All real-time PCR assays were negative. This is the first time that evidence of OPXV exposure has been detected in C. penicillata, a species that usually lives at the interface between cities and forests, increasing risks of zoonotic transmissions through spillover/spillback events. In this way, studies on the circulation of OPXV in neotropical free-living primates are necessary, especially now, with the monkeypox virus being detected in new regions of the planet.

وصف الملف: application/pdf

العلاقة: Pathogens. Basel. Vol. 11, no. 10 (Oct. 2022), 1167, 7 p.; http://hdl.handle.net/10183/250481Test; 001151981

الإتاحة: http://hdl.handle.net/10183/250481Test