↵Peptide based Indirect ELISA for Detection of Antibodies against Peste des petits ruminants virus

Background: Infectious virus antigen is not recommended for disease monitoring in global Peste des petits ruminants eradication strategies. Native virus antigens are gradually being replaced with recombinant or synthetic peptide antigens. The focus of the present study is to optimize and develop peptide-based immunoassay for the detection of antibodies to PPRV N and H proteins. Methods: Epitopes of PPRV H and N proteins were selected based on prediction with bioinformatics tools and from previous studies. Two peptides each were synthesized for N and H proteins and peptide ELISA developed. The peptide ELISA’s sensitivity and specificity were tested with sera samples collected at different time intervals of vaccination (goat =73, sheep= 62) and 88 random serum samples (goat =47, sheep=41). The collected sera were screened using cELISA before proceeding to peptide ELISA. Result: In competitive ELISA, 106 goat serum samples and 96 sheep serum samples were found to be positive. Fourteen goat serum samples and seven sheep serum sample were shown to be negative. Among120 goat serum samples tested, 114 were found to be positive by peptide ELISA. Similarly, out of 103 sheep serum samples analyzed, 96 were found to be positive with peptide ELISA. The peptide ELISA based on the highly conserved and antigenic N and H epitope detected antibodies to PPRV in precise manner. This study demonstrated the effective use of synthetic peptides as an antigen in the detection of antibodies to PPRV.

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Development of an indirect ELISA for detection of antibody against peste des petits ruminants virus in sheep

10.33109/bjvmjj19fam3 ◽

2019 ◽

Vol 1 (17) ◽

Author(s):

F. S. Sumi ◽

M. Nooruzzaman ◽

M. M. Rahman ◽

M. R. Islam ◽

E. H. Chowdhury

Keyword(s):

Indirect Elisa ◽

Viral Disease ◽

Diagnostic Techniques ◽

Virus Antigen ◽

Control Measures ◽

Effective Control ◽

Peste Des Petits Ruminants ◽

Elisa Kit ◽

Antibody Conjugate ◽

Ppr Virus

Background: Emergence of exotic viral disease like peste des petits ruminants(PPR) possesses a great threat towards successful goat and sheep farming in Bangladesh. Implementation of effective control measures against PPR requires a proper and rapid diagnosis of the disease. Various diagnostic techniques are available for diagnosis of PPR in goats and sheep in Bangladesh. Among these, ELISA is an important technique to diagnose the disease as well as for seromonitoring. However, the ELISA kits that are being used in the country are mostly imported. This study was undertaken to develop an in-house indirect ELISA using local PPR virus isolate as an antigen.Methods: A local isolate of PPR virus (PPRV) was used as an antigen to develop an indirect ELISA kit. Standardization of the optimum antibody, conjugate and virus antigen concentration was performed using chequer-board titration with different dilutions of the reagents. Finally, the developed indirect ELISA kit was used in a pilot study to detect anti-PPRV antibodies in sheep sera samples.Results: A polyclonal antibody based indirect ELISA was developed successfully for the detection of PPRV antibodies. The developed ELISA could detect anti-PPRV antibody in sheep sera sample during our pilot field trial.Conclusions: After robust field validation, the indirect ELISA can be used to determine the antibody titer against PPRV in the field as to monitor the seroconversion after vaccination.

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MONITORING STUDIES OF ARBOVIRUS INFECTIONS TRANSMITTED BY MOSQUITOES ON THE TERRITORY OF THE VOLGOGRAD REGION

ЗДОРОВЬЕ НАСЕЛЕНИЯ И СРЕДА ОБИТАНИЯ - ЗНиСО / PUBLIC HEALTH AND LIFE ENVIRONMENT ◽

10.35627/2219-5238/2019-315-6-60-66 ◽

2019 ◽

pp. 60-66

Author(s):

E.V. Molchanova ◽

D.N. Luchinin ◽

A.O. Negodenko ◽

D.R. Prilepskaya ◽

N.V. Boroday ◽

...

Keyword(s):

Virus Antigen ◽

Elisa Test ◽

Serum Samples ◽

Blood Sucking ◽

Tick Borne Encephalitis ◽

Volgograd Region ◽

Two Samples ◽

Probable Presence ◽

California Serogroup ◽

Tick Borne Encephalitis Virus

The paper presents data from the monitoring studies’ results of arbovirus infections transmitted by mosquitoes in the Volgograd region. West Nile virus antigen (WNV) in 9 samples, Tahyna virus in one sample, Batai virus in two samples were detected in the study of 110 samples of field material (blood-sucking mosquitoes) by ELISA test. Antibodies to WNV in 16.58 percent of the samples, to tick-borne encephalitis virus in 1.08 percent, to viruses of the California serogroup and Ukuniemi in 1.09 percent, to the virus Sindbis in 2.17 percent were detected as a result of the study of blood serum samples from donors in the Volgograd region. Thus, we obtained data on the probable presence of the Batai, Sindbis, Ukuniemi and Californian serogroup viruses along with the circulation of WNV on the territory of the Volgograd region.

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Serological Responses to Toxoplasma gondii and Matrix Antigen 1 Predict the Risk of Subsequent Toxoplasmic Encephalitis in People Living with HIV

Clinical Infectious Diseases ◽

10.1093/cid/ciaa1917 ◽

2021 ◽

Author(s):

Jianchun Xiao ◽

Fiona Bhondoekhan ◽

Eric C Seaberg ◽

Otto Yang ◽

Valentina Stosor ◽

...

Keyword(s):

Predictive Performance ◽

Toxoplasmic Encephalitis ◽

People Living With Hiv ◽

Serum Samples ◽

Peptide Antigens ◽

Unit Increase ◽

At Risk Populations ◽

Living With Hiv ◽

Nested Case Control ◽

Control Study

Abstract Background Clinically useful predictors for fatal toxoplasmosis are lacking. We investigated the value of serological assays for antibodies to whole Toxoplasma antigens and to peptide antigens of the Toxoplasma cyst protein MAG1, for predicting incident toxoplasmic encephalitis (TE) in people living with HIV (PLWH). Methods We performed a nested case control study, conducted within the Multicenter AIDS Cohort Study (MACS), using serum samples obtained 2 years prior to diagnosis of TE from 28 cases, and 37 HIV disease-matched Toxoplasma seropositive controls at matched time-points. Sera were tested for Toxoplasma antibodies using a commercial assay and for antibodies to MAG1_4.2 and MAG1_5.2 peptides in ELISA. Results Two years prior to clinical diagnosis, 68% of TE cases were MAG1_4.2 seropositive compared with 16% of controls (OR 25.0, 95% CI 3.14-199.18). Corresponding results for MAG1_5.2 seropositivity were 36% and 14% (OR 3.6, 95% CI 0.95-13.42). Higher levels of antibody to MAG1_4.2 (OR 18.5 per doubling of the OD value, 95% CI 1.41-242) and to Toxoplasma (OR 2.91 for each OD unit increase, 95% CI 1.48-5.72) were also associated with the risk of TE. When seropositivity was defined as the presence of MAG1 antibody or relatively high levels of Toxoplasma antibody, the sensitivity was 89% and specificity was 68% for subsequent TE. Conclusions Antibodies to MAG1 showed predictive value on the occurrence of TE in PLWH, and the predictive performance was further improved by adding the levels of Toxoplasma antibody. These measures could be clinically useful for predicting subsequent diseases in multiple at-risk populations.

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Review of Peste des Petits Ruminants Occurrence and Spread in Tanzania

Animals ◽

10.3390/ani11061698 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1698

Author(s):

Daniel Pius Mdetele ◽

Erick Komba ◽

Misago Dimson Seth ◽

Gerald Misinzo ◽

Richard Kock ◽

...

Keyword(s):

Economic Impact ◽

Disease Surveillance ◽

Grey Literature ◽

Small Ruminants ◽

Peste Des Petits Ruminants ◽

Serum Samples ◽

Eradication Programme ◽

Sheep And Goats ◽

Ruminant Species ◽

Socio Economic Impact

Peste des petits ruminants (PPR) is an important transboundary animal disease of domestic small ruminants, camels, and wild artiodactyls. The disease has significant socio-economic impact on communities that depend on livestock for their livelihood and is a threat to endangered susceptible wild species. The aim of this review was to describe the introduction of PPR to Tanzania and its subsequent spread to different parts of the country. On-line databases were searched for peer-reviewed and grey literature, formal and informal reports were obtained from Tanzanian Zonal Veterinary Investigation Centres and Laboratories, and Veterinary Officers involved with PPR surveillance were contacted. PPR virus (PPRV) was confirmed in northern Tanzania in 2008, although serological data from samples collected in the region in 1998 and 2004, and evidence that the virus was already circulating in Uganda in 2003, suggests that PPRV might have been present earlier than this. It is likely that the virus which became established in Tanzania was introduced from Kenya between 2006–7 through the cross-border movement of small ruminants for trade or grazing resources, and then spread to eastern, central, and southern Tanzania from 2008 to 2010 through movement of small ruminants by pastoralists and traders. There was no evidence of PPRV sero-conversion in wildlife based on sera collected up to 2012, suggesting that they did not play a vectoring or bridging role in the establishment of PPRV in Tanzania. PPRV lineages II, III and IV have been detected, indicating that there have been several virus introductions. PPRV is now considered to be endemic in sheep and goats in Tanzania, but there has been no evidence of PPR clinical disease in wildlife species in Tanzania, although serum samples collected in 2014 from several wild ruminant species were PPRV sero-positive. Similarly, no PPR disease has been observed in cattle and camels. In these atypical hosts, serological evidence indicates exposure to PPRV infection, most likely through spillover from infected sheep and goats. Some of the challenges for PPRV eradication in Tanzania include movements of small ruminants, including transboundary movements, and the capacity of veterinary services for disease surveillance and vaccination. Using wildlife and atypical domestic hosts for PPR surveillance is a useful indicator of endemism and the ongoing circulation of PPRV in livestock, especially during the implementation of vaccination to control or eliminate the disease in sheep and goats. PPR disease has a major socio-economic impact in Tanzania, which justifies the investment in a comprehensive PPRV eradication programme.

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Seroprevalence of the hepatitis E virus antibodies among blood donors in the Qassim region, Saudi Arabia

Future Virology ◽

10.2217/fvl-2021-0013 ◽

2021 ◽

Author(s):

Bader Y Alhatlani ◽

Waleed A Aljabr ◽

Mohammed S Almarzouqi ◽

Sami M Alhatlani ◽

Rayan N Alzunaydi ◽

...

Keyword(s):

Public Health ◽

Saudi Arabia ◽

Blood Transfusion ◽

Hepatitis E Virus ◽

Blood Donors ◽

Indirect Elisa ◽

Hepatitis E ◽

Public Health Issue ◽

Serum Samples ◽

Major Public Health Issue

Aim: Hepatitis E virus (HEV) transmission through blood transfusion is a major public health issue worldwide. We aimed to determine the seroprevalence of HEV in blood donors in the Qassim region of Saudi Arabia. Materials & methods: Serum samples (n = 1078) were collected from volunteer blood donors and tested for the presence of anti-HEV IgG and IgM by indirect ELISA. Results: The seroprevalence of anti-HEV IgG among the blood donors was 5.7% overall. Anti-HEV IgG and IgM seropositivity were significantly higher in non-Saudi donors than in Saudi donors (22.1 vs 3 and 7.8 vs 0.2% for anti-HEV IgG and IgM, respectively). Conclusion: The seroprevalence of HEV among blood donors in the Qassim region was lower than previous estimates for other regions of the country and neighboring countries.

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A multiplex microsphere IgG assay for SARS-CoV-2 using ACE2-mediated inhibition as a surrogate for neutralization

Journal of Clinical Microbiology ◽

10.1128/jcm.02489-20 ◽

2020 ◽

Author(s):

Andrew Cameron ◽

Claire A. Porterfield ◽

Larry D. Byron ◽

Jiong Wang ◽

Zachary Pearson ◽

...

Keyword(s):

Symptom Onset ◽

Chart Review ◽

Infectious Agent ◽

Receptor Binding Domain ◽

Serological Detection ◽

Serum Samples ◽

Time Intervals ◽

Serological Tests ◽

Icu Patients ◽

Fluorescent Microsphere

The COVID-19 pandemic has highlighted the challenges inherent to the serological detection of a novel pathogen such as SARS-CoV-2. Serological tests can be used diagnostically and for surveillance, but their usefulness depends on their throughput, sensitivity and specificity. Here, we describe a multiplex fluorescent microsphere-based assay, 3Flex, that can detect antibodies to three major SARS-CoV-2 antigens—spike (S) protein, the spike ACE2 receptor-binding domain (RBD), and nucleocapsid (NP). Specificity was assessed using 213 pre-pandemic samples. Sensitivity was measured and compared to the Abbott⃝ ARCHITECT⃝ SARS-CoV-2 IgG assay using serum samples from 125 unique patients equally binned (n = 25) into 5 time intervals (≤5, 6 to 10, 11 to 15, 16 to 20, and ≥21 days from symptom onset). With samples obtained at ≤5 days from symptom onset, the 3Flex assay was more sensitive (48.0% vs. 32.0%), but the two assays performed comparably using serum obtained ≥21 days from symptom onset. A larger collection (n = 534) of discarded sera was profiled from patients (n = 140) whose COVID-19 course was characterized through chart review. This revealed the relative rise, peak (S, 23.8; RBD, 23.6; NP, 16.7; in days from symptom onset), and decline of the antibody response. Considerable interperson variation was observed with a subset of extensively sampled ICU patients. Using soluble ACE2, inhibition of antibody binding was demonstrated for S and RBD, and not for NP. Taken together, this study described the performance of an assay built on a flexible and high-throughput serological platform that proved adaptable to the emergence of a novel infectious agent.

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A cross sectional study of leptospirosis and fetal death in Yucatan, Mexico

Colombia Medica ◽

10.25100/cm.v47i1.1975 ◽

2016 ◽

pp. 11-14 ◽

Cited By ~ 2

Author(s):

María Fidelia Cárdenas Marrufo ◽

Ignacio Vado Solis ◽

Gaspar Fernando Peniche Lara ◽

Carlos Perez Osorio ◽

José Correa Segura

Keyword(s):

Spontaneous Abortion ◽

Low Income ◽

Fetal Death ◽

Indirect Elisa ◽

First Trimester ◽

Cross Sectional Study ◽

Sectional Study ◽

Serum Samples ◽

Recent Infection ◽

Cross Sectional

Introduction: Leptospirosis is a zoonotic disease affecting mainly to low income human population. Acute leptospiral infection during pregnancy has been associated with spontaneous abortion and fetal death during the first trimester and the abortion may occur as consequence of systemic failure. Objective: To estimate the frequency of Leptospira interrogans infection in women with spontaneous abortion in the state of Yucatan, Mexico. Methods: A cross sectional study on women with spontaneous abortion was conducted. Serum samples were tested for Leptospirosis by the microaglutination test, to estimate the frequency of the infecting serovar. The indirect ELISA IgM was used to detect recent infection by L. interrogans. DNA was extracted from paraffin-embedded tissue of placenta for PCR detection of L. interrogans. Results: Overall frequency of infection with L. interrogans in the 81 women with abortion was 13.6%. Five of the 12 serovars evaluated were found and included. Two of the 11 women with abortion and positive to microaglutination test were also positive to the ELISA IgM test. None samples were positive for PCR Leptospira diagnosis. Conclusion: two women could be associated with spontaneous abortion due to leptospirosis, because they showed antibodies against L. interrogans in the microaglutination test and ELISA IgM assays. Differences between regions were found with respect to the prevalences of lesptospirosis.

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Determination of Mycoplasma bovis specific antibodies in blood sera of asymptomatic carriers-calves in three farms in the Republic of Serbia by using indirect ELISA assay

Journal of the Hellenic Veterinary Medical Society ◽

10.12681/jhvms.15518 ◽

2017 ◽

Vol 65 (2) ◽

pp. 79

Author(s):

D. VOJINOVIĆ ◽

A. VASIĆ ◽

J. ŽUTIĆ ◽

B. DURIČIĆ ◽

Z. ILIĆ ◽

...

Keyword(s):

Indirect Elisa ◽

Mycoplasma Bovis ◽

Elisa Assay ◽

Serum Samples ◽

Asymptomatic Carriers ◽

Elisa Kit ◽

Cattle Blood ◽

The Republic ◽

The Individual

Blood serum samples of asymptomatic carriers-calves were collected from three farms in the territory of the Republic of Serbia during 2011 and 2012. Commercial Mycoplasma bovis ELISA kit (Bio-X Diagnostics, Belgique) for serological diagnosis from cattle blood sera and milk was used in this research. Calves’ blood sera were tested using immunoenzymatic indirect ELISA assay as described by manufacturer’s instructions. From 5603 blood sera of asymptomatic carriers-calves 144 (2,57%) samples were tested positive for the presence of specific Mycoplasma bovis antibodies. In three different farms proportions of seropositive samples varied from 0,32% to 10,6% in regard to total number of tested samples from the individual farms. In this paper we present the results of Mycoplasma bovis prevalence in asymptomatic carriers-calves.

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