scholarly journals Development of an Indirect ELISA to Detect Equine Antibodies to Theileria haneyi

Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 270
Author(s):  
Reginaldo G. Bastos ◽  
Kelly P. Sears ◽  
Kelcey D. Dinkel ◽  
Lowell Kappmeyer ◽  
Massaro W. Ueti ◽  
...  

The apicomplexan parasite Theileria haneyi is one of two known causative agents of equine theileriosis. It causes milder clinical disease than its more virulent counterpart, Theileria equi, in experimentally infected horses, and can superinfect T. equi-positive horses. The current equi merozoite antigen 1 (EMA1)-based competitive enzyme-linked immunosorbent assay (ELISA)used in the U.S. to detect equine theileriosis detects T. equi but not T. haneyi, and the complexity of molecular assays precludes widespread use for epidemiologic studies. In order to facilitate urgently needed studies on the prevalence of T. haneyi, the goal of this study was to develop a sensitive and specific serologic assay for the diagnosis of T. haneyi based on the equi merozoite antigen 11 (ThEMA11). To achieve this objective, ThEMA11 was recombinantly expressed in eukaryotic cells and its antigenicity assessed using sera from T. haneyi-experimentally infected horses. Confirmation of sera reactivity enabled design and optimization of an indirect ELISA. Specificity of the ELISA for T. haneyi was assessed using a cohort of sera from horses experimentally infected and confirmed PCR-positive for either T. equi or T. haneyi. Data from field samples further demonstrate that the ThEMA11 ELISA is capable of identifying T. haneyi antibodies in horses from multiple continents around the world.


Author(s):  
Reginaldo G. Bastos ◽  
Kelly P. Sears ◽  
Kelcey D. Dinkel ◽  
Lowell Kappmeyer ◽  
Massaro W. Ueti ◽  
...  

The apicomplexan parasite Theileria haneyi is one of two known causative agents of equine theileriosis. It causes milder clinical disease than its more virulent counterpart, Theileria equi, in experimentally infected horses, and can superinfect T. equi-positive horses. The current EMA1-based competitive ELISA used in the U.S. to detect equine theileriosis detects T. equi but not T. haneyi, and the complexity of molecular assays precludes widespread use for epidemiologic studies. In order to facilitate urgently needed studies on the prevalence of T. haneyi, the goal of this study was to develop a sensitive and specific serologic assay for the diagnosis of T. haneyi based on the equi mero-zoite antigen 11 (ThEMA11). To achieve this objective, ThEMA11 was recombinantly expressed in eukaryotic cells and its antigenicity assessed using sera from T. haneyi-experimentally infected horses. Confirmation of sera reactiv-ity enabled design and optimization of an indirect ELISA. Specificity of the ELISA for T. haneyi was assessed using a cohort of sera from horses experimentally infected and confirmed PCR-positive for either T. equi or T. haneyi. Data from field samples further demonstrate that the ThEMA11 ELISA is capable of identifying T. haneyi antibodies in horses from multiple continents around the world.



1990 ◽  
Vol 36 (10) ◽  
pp. 732-735 ◽  
Author(s):  
Perry E. Olsen ◽  
Gordon A. Grant ◽  
Donald L. Nelson ◽  
Wendell A. Rice

American foulbrood, a virulent disease of honeybees, is caused by Bacillus larvae. A murine hybridoma which secretes an IgM monoclonal antibody reactive with B. larvae was derived and an indirect enzyme-linked immunosorbent assay (ELISA) using this monoclonal antibody was evaluated for use in detection of the pathogen. The ELISA detected B. larvae strains from Alberta. and British Columbia, Canada, and from the United States but did not detect six other Bacillus species. The ELISA also detected the presence of B. larvae in field samples collected from commercial apiaries. Results of testing against cultures of B. larvae and infected bee larvae from hives indicate that the monoclonal antibody has, in conjunction with the indirect ELISA technique, potential for use in the diagnosis and confirmation of American foulbrood in commercial apiaries and in honeybee pathology research. Key words: American foulbrood, Bacillus larvae, honeybee disease.



2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Saengsoon Charoenvilaisiri ◽  
Channarong Seepiban ◽  
Mallika Kumpoosiri ◽  
Sombat Rukpratanporn ◽  
Nuchnard Warin ◽  
...  

Abstract Background Cassava mosaic disease (CMD) is one of the most devastating viral diseases for cassava production in Africa and Asia. Accurate yet affordable diagnostics are one of the fundamental tools supporting successful CMD management, especially in developing countries. This study aimed to develop an antibody-based immunoassay for the detection of Sri Lankan cassava mosaic virus (SLCMV), the only cassava mosaic begomovirus currently causing CMD outbreaks in Southeast Asia (SEA). Methods Monoclonal antibodies (MAbs) against the recombinant coat protein of SLCMV were generated using hybridoma technology. MAbs were characterized and used to develop a triple antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) for SLCMV detection in cassava leaves and stems. Assay specificity, sensitivity and efficiency for SLCMV detection was investigated and compared to those of a commercial ELISA test kit and PCR, the gold standard. Results A TAS-ELISA for SLCMV detection was successfully developed using the newly established MAb 29B3 and an in-house polyclonal antibody (PAb) against begomoviruses, PAb PK. The assay was able to detect SLCMV in leaves, green bark from cassava stem tips, and young leaf sprouts from stem cuttings of SLCMV-infected cassava plants without cross-reactivity to those derived from healthy cassava controls. Sensitivity comparison using serial dilutions of SLCMV-infected cassava sap extracts revealed that the assay was 256-fold more sensitive than a commercial TAS-ELISA kit and 64-fold less sensitive than PCR using previously published SLCMV-specific primers. In terms of DNA content, our assay demonstrated a limit of detection of 2.21 to 4.08 × 106 virus copies as determined by quantitative real-time PCR (qPCR). When applied to field samples (n = 490), the TAS-ELISA showed high accuracy (99.6%), specificity (100%), and sensitivity (98.2%) relative to the results obtained by the reference PCR. SLCMV infecting chaya (Cnidoscolus aconitifolius) and coral plant (Jatropha multifida) was also reported for the first time in SEA. Conclusions Our findings suggest that the TAS-ELISA for SLCMV detection developed in this study can serve as an attractive tool for efficient, inexpensive and high-throughput detection of SLCMV and can be applied to CMD screening of cassava stem cuttings, large-scale surveillance, and screening for resistance.



Viruses ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1358
Author(s):  
Brigitte Sigrist ◽  
Jessica Geers ◽  
Sarah Albini ◽  
Dennis Rubbenstroth ◽  
Nina Wolfrum

Avian bornaviruses were first described in 2008 as the causative agents of proventricular dilatation disease (PDD) in parrots and their relatives (Psittaciformes). To date, 15 genetically highly diverse avian bornaviruses covering at least five viral species have been discovered in different bird orders. Currently, the primary diagnostic tool is the detection of viral RNA by conventional or real-time RT-PCR (rRT-PCR). One of the drawbacks of this is the usage of either specific assays, allowing the detection of one particular virus, or of assays with a broad detection spectrum, which, however, do not allow for the simultaneous specification of the detected virus. To facilitate the simultaneous detection and specification of avian bornaviruses, a multiplex real-time RT-PCR assay was developed. Whole-genome sequences of various bornaviruses were aligned. Primers were designed to recognize conserved regions within the overlapping X/P gene and probes were selected to detect virus species-specific regions within the target region. The optimization of the assay resulted in the sensitive and specific detection of bornaviruses of Psittaciformes, Passeriformes, and aquatic birds. Finally, the new rRT-PCR was successfully employed to detect avian bornaviruses in field samples from various avian species. This assay will serve as powerful tool in epidemiological studies and will improve avian bornavirus detection.



1994 ◽  
Vol 6 (2) ◽  
pp. 175-181 ◽  
Author(s):  
A. Lucchelli ◽  
S. Y. Kang ◽  
M. K. Jayasekera ◽  
A. V. Parwani ◽  
D. H. Zeman ◽  
...  

Group A bovine rotaviruses (BRV) have been identified worldwide as a major cause of diarrhea in the young of many species, including humans. Group A rotaviruses are classified into serotypes on the basis of the outer capsid proteins, VP7 (G types) and VP4 (P types). To date, there are 14 G types of group A rotaviruses, with G1, G6, G8, and G10 described for BRV isolates. In this study, G6- and G lo-specific monoclonal antibodies (MAbs) were used in an enzyme-linked immunosorbent assay (ELISA) for the G typing of BRV-positive stool samples from diarrheic beef and dairy calves from South Dakota, Ohio, Michigan, Nebraska, and Washington, USA, and Ontario, Canada. ELISA plates were coated using a broadly reactive VP7 MAb (Common 60) or with G6- or G10-specific MAbs. BRV-positive fecal samples were diluted and added to duplicate wells, followed by the addition of polyclonal guinea pig anti-group A rotavirus serum as the secondary antibody. Several reference G6 and G10 BRV strains as well as other G types previously reported in cattle (G1, G2, G3, G8) and BRV-negative samples were included as G type specificity and negative controls. From a total of 308 field samples analyzed, 79% (244/308) tested positive by the broadly reactive VP7 MAb; of these, 54% (131/244) were G6 positive, 14% (35/244) were G10 positive, 4% (9/244) were both G6 and G10 positive, and 28% (69/244) were G6 and G10 negative. The negative samples may represent additional or undefined serotypes. The 89 samples from South Dakota were further subdivided into samples from beef ( n = 43) or dairy ( n = 46) herds. G6 was more prevalent in beef herd samples (67%) than in dairy herd samples (47.5%). In addition, dairy herds had higher percentages of G10-positive samples (17.5%) G6-G10 double positives (10%), and untypable samples (25%) than did beef herds, in which the prevalence of G10 positive samples was 5.5%, G6-G10 double positives was 5.5%, and untypable samples was 22%. Application of the serotype ELISA for the analysis of additional BRV samples will provide further epidemiologic data on the distribution of BRV serotypes in beef or dairy cattle, an important consideration for the development of improved BRV vaccines.



Plant Disease ◽  
2002 ◽  
Vol 86 (9) ◽  
pp. 1052-1052 ◽  
Author(s):  
K. Gebre-Selassie ◽  
B. Delecolle ◽  
P. Gognalons ◽  
O. Dufour ◽  
C. Gros ◽  
...  

In summer 2000, symptoms similar to Pelargonium zonate spot virus (PZSV) were observed for the first time on tomato plants in southeastern France. The plants were from commercial glasshouse fresh-market crops. Symptoms observed were chlorotic mottling with bright yellow distinct rings on leaves and curved line patterns on stems. Fruit symptoms included chlorotic and necrotic spotting, marked concentric ring patterns, and distortions. Diagnosis was made from symptomatic leaves and fruits by mechanical inoculation on a set of host plants. Local chlorotic and necrotic lesions were observed on Chenopodium amaranticolor, C. quinoa, Cucumis sativus cv. Marketer, Cucumis melo cv. Vedrantais, Phaseolus vulgaris cv. Pinto, Vicia faba cv. D'Aguadulce, Vigna unguiculata cv. Black Eye, and systemic symptoms were observed on Capsicum annuum cvs. Yolo Wonder, Yolo Y, Florida VR2, and Criollo de Morelos 334, Datura stramonium, Lycopersicon esculentum cvs. Momor and Stevens, L. hirsutum (PI 134417 and PI 247087), Nicotiana benthamiana, N. clevelandii, N. tabacum cv. Xanthi nc, Ocimum basilicum cv. Latino, Petunia hybrida cv. Rose du ciel, and Physalis floridana. No reaction was observed on Pisum sativum cv. Douce Provence, Salvia splendens cv. Etna, or Zinnia elegans cv. Liliput. Symptoms on tomato of PZSV, Parietaria mottle virus (PMoV), and Tomato spotted wilt virus (TSWV) are similar, particularly those elicited in fruits. Therefore, the field samples were checked using double-antibody sandwich enzyme-linked immunosorbent assay against antisera of the type-strain of PZSV and tomato strain of PMoV and their homologous antigenes, which were supplied by D. Gallitelli and P. Roggero respectively, and our antiserum of TSWV. Electron microscopy of negatively stained preparations from leaves of tomato and D. stramonium showed that the sap contained very few paraspheric shaped particles, 26 to 29 nm in diameter. Three isolates collected from two different regions (Vaucluse and Bouches du Rhône) showed a very close serological relationship with the Italian type-strain of PZSV and tested negative against antisera of PMoV and TSWV. The French isolates were biologically different from the type-strain, but were similar to the Spanish strain of PZSV because they infected D. stramonium, N. benthamiana, O. basilicum, and V. unguiculata (2). Moreover, in transverse tissue sections, virions were not observed in the nucleus and tubular structures, unlike the Italian isolates, (1) but were present in the cytoplasm and particularly in the mesophyll cells. There are only a few records of the occurrence and distribution of PZSV in Mediterranean countries. References: (1) M. A Castellano and G. P Martelli. Phytopathol. Mediterr. 20:64, 1981. (2) M. Luis-Arteaga. Plant Dis. 84:807, 2000.



Plant Disease ◽  
1999 ◽  
Vol 83 (9) ◽  
pp. 880-880 ◽  
Author(s):  
G. R. G. Clover ◽  
D. M. Wright ◽  
C. M. Henry

In April 1999, severe soilborne wheat mosaic virus (SBWMV) symptoms were observed in five fields of winter wheat (Triticum aestivum, cvs. Consort, Equinox, and Savannah) on one farm in Wiltshire, UK. Affected plants were markedly stunted and had a pale mosaic on their leaf sheaths that developed into bright yellow, parallel streaks on the leaves as they unfolded. Symptomatic plants were found in discrete, elliptical patches ranging in size from a few square meters to nearly a hectare. During May and June, symptoms became less marked as temperatures increased and were restricted to lower leaves. SBWMV was positively identified in all five fields (60 to 170 plants per field) by double (W. Huth, BBA-Braunschweig, Germany; Sanofi Phyto-Diagnostics, Paris) and triple (T. Wilson, SCRI, Dundee, UK) antibody sandwich enzyme-linked immunosorbent assay and by reversetranscription polymerase chain reaction (2). Identification was confirmed by immunoelectron microscopy, including protein-A gold labeling, which revealed bipartite, rod-shaped particles typical of SBWMV. Neither wheat spindle streak mosaic virus nor barley yellow dwarf virus was detected in the field samples, nor was SBWMV detected in any other field subsequently sampled, despite a survey of the surrounding area. Wheat is the most important economic crop in the United Kingdom (≈1.9 million hectares are grown annually, yielding ≈16 million tonnes), but its position is threatened by the economic impact of SBWMV, which has decreased yields by up to 50% in the United States (1). References: (1) T. A. Kucharek and J. H. Walker. Plant Dis. Rep. 58:763, 1974. (2) R. E. Pennington et al. Plant Dis. 77:1202, 1993.



1987 ◽  
Vol 70 (4) ◽  
pp. 657-661
Author(s):  
Titan S L Fan ◽  
Yi-Chun Xu ◽  
Fun Sun Chu

Abstract An indirect enzyme-linked immunosorbent assay (ELISA) for the detection of HT-2 toxin in the presence or absence of T-2 toxin is described. In the indirect ELISA, the relative cross-reactivities of antibodies against T-2 toxin (anti-T-2) with T-2 toxin and HT-2 toxin were 1 and 0.1, whereas anti-HT-2 cross-reactivities with T-2 toxin and HT-2 toxin were 0.33 and 1, respectively. Using such relationships, a formula was established that could be used to calculate the individual toxin concentration in a mixed sample after experimentally analyzing for T-2 and HT-2 toxins in the 2 indirect ELISAs. This method was tested by analyzing urine samples spiked with HT-2 toxin alone and samples spiked with both T-2 toxin and HT-2 toxin. A cleanup protocol for treatment of urine samples before ELISA was also established. The overall analytical recovery of HT-2 toxin when it was added at concentrations of 0.1-10 parts per billion (ppb) to the urine samples was ca 89%. When both T-2 and HT-2 toxins were added to the urine samples at equal concentrations of 0.5 to 5.0 ppb, their recoveries were 112 and 109%, respectively.



1998 ◽  
Vol 61 (4) ◽  
pp. 476-481 ◽  
Author(s):  
YUN-HWA P. HSIEH ◽  
SHYANG-CHWEN SHEU ◽  
ROGER C. BRIDGMAN

Detection of species adulteration in ground meat products is important for consumer protection and food-labeling law enforcement. This study was conducted to develop monoclonal antibodies (MAbs) that can be used in an enzyme-linked immunosorbent assay (ELISA) for rapid detection of any cooked mammalian meats in cooked poultry products. Soluble muscle proteins extracted from cooked pork (heated at 100°C for 15 min) were used as the antigen to immunize mice for developing the MAb. One that was developed, MAb 2F8 (IgG2b class), strongly reacted with cooked meat of five mammalian species (beef cattle, hogs, sheep, horse, and deer) but did not react with any cooked poultry (chicken, turkey, and duck) or raw meats. At least 0.5% by weight of pork, beef, lamb, and horse meats in a chicken-based mixture could be detected using an indirect ELISA with MAb 2F8. The MAb 2F8 is useful in a single initial screening test to detect the presence of five nonpoultry meat adulterants in cooked poultry products.



2007 ◽  
Vol 75 (4) ◽  
pp. 2004-2011 ◽  
Author(s):  
Jianli Shi ◽  
Zhengmin Yang ◽  
Min Wang ◽  
Guoyan Cheng ◽  
Ding Li ◽  
...  

ABSTRACT Epidemiologic studies indicated that some infertile men who were infected with Ureaplasma urealyticum displayed positive antisperm antibodies in their serum and/or semen. The purpose of this study was to investigate the possible mechanism of antisperm antibodies production after infection with U. urealyticum and to analyze the relationship between U. urealyticum and infertility. The existence of cross-reactive antigens (61, 50, and 25 kDa) between U. urealyticum and human sperm membrane proteins was confirmed. Among the cross-reactive antigens, the urease complex component UreG of U. urealyticum was determined. By searching the Swiss-Prot protein database, a pentapeptide identity (IERLT) between UreG and human nuclear autoantigenic sperm protein (NASP) was found. Furthermore, using Western blot analysis and enzyme-linked immunosorbent assay, the cross-reaction between the NASP and UreG was verified. Both anti-rUreG antibody and the antiserum against the synthetic peptide NASP393-408 containing the pentapeptide inhibited mouse sperm egg binding and fusion. After immunization by rUreG or the synthetic peptide, 81.2 and 75% female mice became sterile, respectively. The effect on fertility in mice immunized with the synthetic peptide was reversible. These findings proved for the first time that it was feasible to screen antigens for immunocontraceptives from cross-reactive antigens between sperm and microorganisms which induce infertility.



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