Analysis of the serological variability of Lettuce mosaic virus using monoclonal antibodies and surface plasmon resonance technology

A panel of 19 monoclonal antibodies (mAbs) was used to study the immunological variability of Lettuce mosaic virus (LMV), a member of the genus Potyvirus, and to perform a first epitope characterization of this virus. Based on their specificity of recognition against a panel of 15 LMV isolates, the mAbs could be clustered in seven reactivity groups. Surface plasmon resonance analysis indicated the presence, on the LMV particles, of at least five independent recognition/ binding regions, correlating with the seven mAbs reactivity groups. The results demonstrate that LMV shows significant serological variability and shed light on the LMV epitope structure. The various mAbs should prove a new and efficient tool for LIVIV diagnostic and field epidemiology studies.

Use of near-infrared Raman spectroscopy to detect IgG and IgM antibodies against Toxoplasma gondii in serum samples of domestic cats

Near-infrared Raman spectroscopy (NIRS) is a particularly promising technique that is being used in recent years for many biomedical applications. Optical spectroscopy has gained increasing prominence as a tool for quantitative analysis of biological samples, clinical diagnostic, concentration measurements of blood metabolites and therapeutic drugs, and analysis of the chemical composition of human tissues. Toxoplasmosis is an important zoonosis in public health, and domestic cats are the most important transmitters of the disease. This disease can be detected by several serological tests, which usually have a high cost and require a long time. The goal of this work was to investigate a new method to diagnosis Toxoplasma gondii infections using NIRS. In order to confirm antibody detection, 24 cat blood scrum samples were analyzed by the Raman spectra, from which 23 presented positive serology to toxoplasmosis and one was a reference negative serum. Characteristic Raman peaks allowed differentiation between negative and positive sera, confirming the possibility of antibody detection by Raman spectroscopy. These results give the first evidence that this technique can be useful to quantify antibodies in cat sera.

Geographic analysis on the occurrence of human and canine leptospirosis in the city of Maringá, state of Paraná, Brazil

INTRODUÇÃO: Leptospirose é uma zoonose que tem como hospedeiros primários os animais silvestres, sinantrópicos e domésticos. Os humanos comportam-se como hospedeiros terminais e acidentais. Sua prevalência depende dos animais portadores que disseminam o agente, de sua sobrevivência ambiental e do contato de pessoas susceptíveis. Cada sorovar tem um ou mais hospedeiros com diferentes níveis de adaptação. Os focos de leptospirose devem-se aos animais infectados, doentes e assintomáticos, considerados como fontes de infecção ambiental. O objetivo deste estudo foi determinar áreas de risco da infecção leptospírica em cães errantes e pacientes com diagnóstico de leptospirose nos anos de 2006 a 2008, em Maringá, Estado do Paraná, Brasil. MÉTODOS: Foram estudados 335 cães errantes e 25 pacientes. Os soros, tanto dos animais como dos pacientes, foram examinados pela prova de soroaglutinação microscópica (SAM), para pesquisa de anticorpos antileptospíricos. Para determinar áreas de risco e a distribuição espacial da doença foram elaborados mapas temáticos. RESULTADOS: Foram observados 41(12,2%) cães positivos para um ou mais sorovares de leptospiras, e os mais frequentes foram: Pyrogenes (43,9%), Canícola (21,9%) e Copennhageni (19,5%). Nos humanos, a positividade foi de 2 (8%) para os sorovares, Pyrogenes e Hardjo Prajitno e, Pyrogenes e Cynopteri. CONCLUSÕES: A análise espacial revelou que o risco de cães e humanos, no município de Maringá, se infectar com leptospiras está presente tanto em áreas centrais como periféricas, fato que reforça a relevância deste estudo e de ações contínuas de vigilância epidemiológica e ambiental para o controle da doença tanto nos animais como no homem.

Detection and molecular analysis of Toxoplasma gondii and Neospora caninum from dogs with neurological disorders

Introduction: Toxoplasma gondii and Neospora caninum are related Apicomplexa parasites responsible for systemic diseases in many species of animals, including dogs. Methods: This study aimed to determine the occurrence of T. gondii and N. caninum infections in 50 dogs with neurological signs that were admitted to the Veterinary Hospital of Universidade Estadual Paulista, City of Botucatu, Brazil. All animals were screened for antibodies using an immunofluorescent antibody test for both parasites. Tissues of positive animals were bioassayed in mice (T. gondii) and gerbils (N. caninum), and DNA was analyzed using the polymerase chain reaction (PCR). Positive samples for T. gondii by PCR were typed using restriction fragment length polymorphism-PCR for 11 markers: SAG1, SAG2 (5'-3'-SAG2 and alt.SAG2), SAG3, Btub, GRA6, L358, c22-8, c29-6, PK1 and Apico, and CS3 marker for virulence analysis. Results: Specific antibodies were detected in 11/50 (22%; 95% confidence interval (CI95%), 12.8-35.3%) animals for T. gondii and 7/50 (14%; CI95%, 7.02-26.3%) for N. caninum. In the bioassay and PCR, 7/11 (63.6%; CI95%, 34.9-84.8%) samples were positive for T. gondii and 3/7 (42.9%; CI95% I, 15.7-75.5%) samples were positive for N. caninum. Three different genotypes were identified, but only 1 was unique. Conclusions: These data confirm the presence of T. gondii and N. caninum in dogs from Brazil, indicating the importance of this host as a sentinel of T. gondii for human beings, and the genotypic variation of this parasite in Brazil.

Comparison between the counter immunoelectrophoresis test and mouse neutralization test for the detection of antibodies against rabies virus in dog sera

The detection of rabies antibodies is extremely valuable for epidemiological studies, determination of immune status in man, animals, and for the diagnosis of the disease. Several serological procedures have been described for this purpose. The present study reports a comparison between counterimmunoelectrophoresis test (CIET) and mouse neutralization test (MNT) in the detection of antibodies against rabies virus from 212 serum samples of vaccinated dogs. The agreement between both techniques was 79.7% and a significative association was demonstrated. The correlation coefficients between MNT and the CIET titers was determined considering 88 samples showing positive results in both techniques [CIET = 2 and MNT = 5 (0.13 IU/ml)] and resulted r² = 0.7926 (p < 0.001). The performance of CIET system was technically simple, cheap and rapid, and thereby it could be useful for serological monitoring of dog vaccination campaigns as well as for individual analysis.

Analysis of proteins from membrane and soluble fractions of Giardia duodenalis trophozoites of two Brazilian axenic strains

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Detection of antibodies against Babesia bovis and Babesia bigemina in calves from the region of Araguaína, State of Tocantins, Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Detection and quantification of antibodies to Newcastle disease virus in ostrich and rhea sera using a liquid phase blocking enzyme-linked immunosorbent assay

A liquid phase blocking ELISA (LPB-ELISA) was adapted for the detection and quantification of antibodies to Newcastle disease virus. Sera from vaccinated and unvaccinated commercial flocks of ostriches (Struthio camelus) and rheas (Rhea americana) were tested. The purified and nonpurified virus used as the antigen and the capture and detector antibodies were prepared and standardized for this purpose. The hemagglutination-inhibition (HI) test was regarded as the reference method, the cutoff point for the LPB-ELISA was determined by a two-graph receiver operating characteristic analysis. The LPB-ELISA titers regressed significantly (P < 0.0001) on the HI titers with a high correlation coefficient (r = 0.875). The two tests showed good agreement ( = 0.82; P < 0.0001), relative sensitivity (90.91%) and specificity (91.18%), and accuracy (91.02%), suggesting that they are interchangeable.

Near-infrared Raman spectroscopy to detect anti-Toxoplasma gondii antibody in blood sera of domestic cats: quantitative analysis based on partial least-squares multivariate statistics

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Antisperm antibodies in infertile men and their correlation with seminal parameters

Aim: Antisperm antibodies (ASA) in males cause the autoimmune disease 'immune infertility'. The present study intended to detect the presence of ASA and their incidence in men with unexplained infertility, as well as to evaluate the correlation between the presence of ASA and semen parameter alterations. Methods: Blood and sperm assessment were collected to carry out a direct and indirect mixed antiglobulin reaction (MAR) test and semen analysis in infertile and fertile men from the University Hospital of the Faculty of Medicine, Sao Paulo State University, Sao Paulo. Results: In the MARtest, 18.18% of infertile men were positive for ASA. In fertile men, no positivity was found. A significant correlation between the presence of ASA with an increased white blood cell count plus a decreased hypoosmotic swelling test result was observed. Conclusions: The results indicate that ASA are involved in reduced fertility. It is not ASA detection per.se that provides conclusive information about the occurrence of damage to fertility. The correlation between infertility and altered seminal parameters reinforce the ASA participation in this pathology. © 2007 The Authors Journal compilation. © 2007 Japan Society for Reproductive Medicine.

A Bayesian approach to estimate the accuracy of in-house ELISA assay to measure rabies antibodies from compulsory vaccinated dogs and cattle

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Clinical, serological, and parasitological analysis of snakes naturally infected with Cryptosporidium serpentis

Infection by Cryptosporidium serpentis is one of the most important diseases in reptiles and is characterized by chronic clinical or subclinical infection and the presence of hypertrophic gastritis, food regurgitation, progressive weight loss, mortality, and intermittent or continuous shedding of oocysts in the feces. The objectives of this study were to standardize an indirect enzyme-linked immunosorbent assay (ELISA) to detect antibodies against C. serpentis and to evaluate the clinical, parasitological, and humoral immune response in snakes naturally infected with C. serpentis. Twenty-one snakes naturally infected with C. serpentis and housed at the Butantan Institute, São Paulo, Brazil, underwent clinical and parasitological analyses for C. serpentis infection through daily records of clinical signs and a monthly survey of fecal shedding of oocysts using the Kinyoun's acid-fast staining. The serological evaluation was performed monthly by indirect ELISA using crude total antigen from oocysts of C. serpentis to detect anti-C. serpentis antibodies. Clinical symptoms consisted of food regurgitation, inappetence, and progressive weight loss. The parasitological analysis revealed intermittent fecal shedding of a variable number of oocysts in all snakes, with positivity in 85.32% (157/184) of the samples. The indirect ELISA was positive in 68.25% (86/126) of the samples. A humoral immune response was observed in most animals; however, fluctuating antibodies levels, leading to alternating positive and negative results, were observed in most snakes. © 2013 Elsevier B.V. All rights reserved.

Prevalence of antibodies against Toxoplasma gondii and Neospora caninum in dogs

Toxoplasmosis and neosporosis are parasitic diseases of global importance. The present study had the objective to determine the influence of age, sex and breed in the prevalence of antibodies against both diseases in dogs from Brotas city, São Paulo State, Brazil. Blood samples of 342 dogs were collected, and the age, sex and breed of each animal were recorded. The serological diagnosis for toxoplasmosis and neosporosis were performed using the immunofluorescent antibody test (IFAT). The Fischer's test was used to calculate the association probability of the variables, with a = 5%. For toxoplasmosis the prevalence of antibodies was 26.9% (CI 95% 22.4-31.8%), and for neosporosis 4.97% (CI 95% 3.1-7.8%). The statistical analysis revealed a higher risk of infection for T. gondii in dogs with more than five years.

Risk factors and presence of antibodies to Brucella canis and smooth Brucella in dogs from the municipality of Araguaina, Tocantins, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Alkylation of Histidine Residues of Bothrops jararacussu Venom Proteins and Isolated Phospholipases A(2): A Biotechnological Tool to Improve the Production of Antibodies

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)