IgY antibody and human neurocysticercosis: a novel approach on immunodiagnosis using Taenia crassiceps hydrophobic antigens.

Human neurocysticercosis (NCC) is a worldwide neglected disease caused by Taenia solium metacestode and responsible for various complications and neurological disorders. This study aimed to evaluate the use of specific immunoglobulin Y (IgY) produced by laying hens immunized with a hydrophobic fraction of Taenia crassiceps metacestodes (hFTc) in NCC diagnosis. Egg yolk IgY antibodies were fractionated, purified and characterized. Enzyme-linked immunosorbent assay (ELISA) was carried out to evaluate the production kinetics and avidity maturation of anti-hFTc IgY antibodies throughout the IgY obtention process. Antigen recognition tests were carried out by Western blotting and immunofluorescence antibody test using purified and specific anti-hFTc IgY antibodies for detection of parasitic antigens of T. crassiceps and T. solium metacestodes. Sandwich ELISA was performed to detect circulating immune complexes formed by IgG and parasitic antigens in human sera. The results showed high diagnostic values (93.2% sensitivity and 94.3% specificity) for immune complexes detection in human sera with confirmed NCC. In conclusion, specific IgY antibodies produced from immunized hens with hFTc antigens were efficient to detect T. solium immune complexes in human sera, being an innovative and potential tool for NCC immunodiagnosis.

Use of polyclonal IgY antibodies to detect serum immune complexes in patients with active hookworm infection.

Definitive diagnosis of hookworm infection is usually based on the microscopic detection of eggs in a stool sample; however, several cases display a low or irregular egg output. Serodiagnosis can be a useful tool to identify these cases, but conventional tests do not differentiate past from active infections. The aim of this study was to obtain and apply egg yolk polyclonal immunoglobulin (IgY) antibodies to detect immune complexes (ICs) in serum samples from patients infected with hookworm. Hens were immunized with Ancylostoma ceylanicum saline extract, their eggs were collected and then IgY antibodies were extracted and purified. Antibody purity was tested by 12% sodium dodecyl sulphate polyacrylamide gel electrophoresis and specificity was assessed by immunoblotting and immunofluorescence. IgY production was evaluated by kinetics enzyme-linked immunosorbent assay (ELISA). Sandwich ELISA tested the ability of IgY to detect ICs in serum samples, from which diagnostic parameters were calculated. Antibody responses increased steadily from day 7 to 42. In the immunoblotting assay, IgY recognized two protein complexes. The immunofluorescence assay showed no staining in control samples. The sandwich ELISA presented a very high diagnostic value, with a sensitivity of 90% and a specificity of 86.7%. Our pioneer strategy highlights the potential use of egg yolk IgY as a diagnostic test to detect active hookworm infection.

First occurrence of feline sporotrichosis in a metropolitan area of Central-West Brazil.

Sporotrichosis is a neglected mycosis that affects human and animal hosts, including domestic cats. In Brazil, its most frequently diagnosed etiological agent is Sporothrix brasiliensis. Zoonotic transmission of S. brasiliensis occurs via direct contact between an infected cat and a susceptible human host. Notification of confirmed cases of feline sporotrichosis is not mandatory in Brazil. The metropolitan area of Goiania city can be considered a silent area for the occurrence of feline sporotrichosis. In this context, voluntary reporting of feline sporotrichosis cases is recommended for all healthcare professionals. This study aimed to report the first occurrence of S. brasiliensis in a cat from the metropolitan area of Goiania city. Cytopathology, mycology, thermal dimorphism and calmodulin gene amplification tests were performed. The mycological and molecular biological diagnoses corresponded to S. brasiliensis. The etiological agent of zoonotic sporotrichosis was detected in the metropolitan area of Goiania city, and therefore there is a risk of the emergence of new cases of cats infected with S. brasiliensis and the occurrence of zoonotic transmission of this fungus.

IgG4 and IgE anti-Strongyloides stercoralis as additional parameters in characterizing patients with diabetes from a hyperendemic area.

We report the detection of IgG, IgG1, IgG4 and IgE anti-Strongyloides stercoralis as complementary tool for screening in patients with diabetes in hyperendemic areas for strongyloidiasis. A panel of 119 serum samples were analyzed: 76 from patients with DM2 and 43 patients with other endocrine diseases and a positive correlation for total IgG levels with IgG4 (rs = 0.559; P = 0.024; n = 16) and IgG and IgE (rs = 0.585; P < 0.0001; n = 76) was found in the diabetes group.

Seroprevalence of Equine Leptospirosis in the State of Goiás, Brazil.

Leptospirosis, caused by Leptospira, is a zoonotic disease that, in horses, is linked to abortions, uveitis, and sporadic occurrences of liver and kidney disease, often resulting in significant economic losses for farmers. Research on the prevalence of leptospirosis in horses in the central-west region of Brazil has been relatively scarce. Thus, the present study aimed to determine the prevalence of leptospirosis in equine herds in the state of Goiás (Central Brazil). Blood samples were collected from 894 equids at 294 randomly selected farms divided into three different strata according to their herd characteristics. The microscopic agglutination test for the detection of anti-Leptospira agglutinins was carried out and the results showed that among the 294 sampled farms, 213 (72.9%; CI 95% 71.7-78.9) had one or more animals positive for leptospirosis, and of the 894 horses sampled, 513 (61.6%; CI 95% 54.3-69.0) were seropositive for leptospirosis. Djasiman, Icterohaemorrhagiae, and Australis were the most prevalent serogroups. The results showed a high prevalence of seropositive animals and a widespread distribution of positive farms in the state of Goiás. Thus, environmental sanitation measures and health education to prevent and control equine leptospirosis in the state are required.

A recombinant protein (MyxoTLm) for the serological diagnosis of acute and chronic Trypanosoma vivax infection in cattle.

Human trypanosomiases and animal trypanosomoses are caused by distinct protozoan parasites of the genus Trypanosoma. The etiological agents of bovine trypanosomosis (BT) are T. vivax, T. congolense, or T. brucei, whose acute infections are initially characterized by hyperthermia, following moderate to severe anemia, subcutaneous edema, lethargy, reduced milk production, progressive weight loss, enlarged lymph nodes, reproductive disorders and death. Animals that survive the acute phase might recover and progress to the chronic, often asymptomatic, phase of infection. Despite their low sensitivity due to the characteristic low parasitemia, simple and costless direct parasitological examinations are the preferred diagnostic methods for animals. Thus, most of the epidemiological studies of BT are based on serological techniques using crude antigen. In this study, we describe the use of the MyxoTLm recombinant protein as an antigen on serological assays. Anti-T. vivax IgM and anti-T. vivax IgG ELISA assays using purified MyxoTLm revealed specificity rates of 91.30 % and 95.65 % and sensitivity rates of 82.35 % and 88.23 %, respectively, being higher than reported for crude antigens. Also, MyxoTLm demonstrated a good performance to detect IgM (ROC curve area = 0.8568) and excellent performance to detect IgG (ROC curve area = 0.9565) when compared to a crude antigen. T. evansi crude antigen used in the indirect anti-T. vivax IgM ELISA reached 70.58 % sensitivity and 78.26 % specificity, and had a lower test performance (ROC curve area = 0.7363). When applied to the anti-T. vivax IgG ELISA, the crude antigen reached 82.35 % sensitivity and 69.56 % specificity, also presenting a low performance with area under the ROC curve of 0.7570. Therefore, the use of MyxoTLm as an antigen on serological diagnosis of BT revealed to increase the sensitivity and the specificity if compared to crude antigens.

Toxoplasma gondii in cattle in Brazil: a review.

Toxoplasma gondii is an apicomplexan protozoan that is frequently found in both humans and animals worldwide. The aim of this review was to list important aspects of Toxoplasma gondii infection in cattle in Brazil. The frequency of occurrence of T. gondii antibodies in Brazilian cattle ranges from 1 to 89.1%, depending on the region evaluated, based on data from 1978 to 2018. However, some characteristics of T. gondii infection in cattle remain uncertain, such as the role of meat intake in transmitting the parasite to humans. Most information regarding T. gondii infection among Brazilian cattle is limited to evaluations of the frequency of occurrence of antibodies. About 70% of the diagnoses of infection in these ruminants in Brazil are made via the indirect fluorescence antibody test (IFAT). Nevertheless, little is known about the population structure of this protozoan in cattle. It is necessary to expand the studies on toxoplasmosis in cattle, in order to better understand T. gondii infection in these animals and its implications for Brazilian public health.

Highly specific and sensitive anti-Strongyloides venezuelensis IgY antibodies applied to the human strongyloidiasis immunodiagnosis.

Due to the epidemiological problem of the neglected condition of human strongyloidiasis, rapid and effective diagnosis is extremely important, with the development of new diagnostic tools being essential to reduce infections and chronic cases. Avian immunoglobulin Y (IgY) technology is an alternative for antibody production that has high specificity and profitability. This study aimed to produce and fractionate IgY antibodies from the egg yolks of hens that were immunized with the total antigenic extracts of Strongyloides venezuelensis infectious filariform larvae (iL3) and parthenogenetic females (pF). IgY antibodies were then evaluated by their recognition of antigenic proteins, evolutive helminth forms, and serological diagnosis of human strongyloidiasis by the detection of immune complexes in serum samples. Egg yolks were fractionated to obtain IgY antibodies by thiophilic interaction chromatography. Immune complex detection in serum samples showed diagnostic values for anti-iL3 IgY and anti-pF IgY antibodies at 95.56% and 88.89% sensitivity and 95.56% and 91.11% specificity, respectively. Therefore, IgY technology is a promising tool for the detection of blood circulating Strongyloides antigens, with possible application as a serological diagnostic method.

First occurrence of feline sporotrichosis in a metropolitan area of Central-West Brazil

ABSTRACT Sporotrichosis is a neglected mycosis that affects human and animal hosts, including domestic cats. In Brazil, its most frequently diagnosed etiological agent is Sporothrix brasiliensis. Zoonotic transmission of S. brasiliensis occurs via direct contact between an infected cat and a susceptible human host. Notification of confirmed cases of feline sporotrichosis is not mandatory in Brazil. The metropolitan area of Goiania city can be considered a silent area for the occurrence of feline sporotrichosis. In this context, voluntary reporting of feline sporotrichosis cases is recommended for all healthcare professionals. This study aimed to report the first occurrence of S. brasiliensis in a cat from the metropolitan area of Goiania city. Cytopathology, mycology, thermal dimorphism and calmodulin gene amplification tests were performed. The mycological and molecular biological diagnoses corresponded to S. brasiliensis. The etiological agent of zoonotic sporotrichosis was detected in the metropolitan area of Goiania city, and therefore there is a risk of the emergence of new cases of cats infected with S. brasiliensis and the occurrence of zoonotic transmission of this fungus.

Toxoplasma gondii in cattle in Brazil: a review / Toxoplasma gondii em bovinos no Brasil: uma revisão

Abstract Toxoplasma gondii is an apicomplexan protozoan that is frequently found in both humans and animals worldwide. The aim of this review was to list important aspects of Toxoplasma gondii infection in cattle in Brazil. The frequency of occurrence of T. gondii antibodies in Brazilian cattle ranges from 1 to 89.1%, depending on the region evaluated, based on data from 1978 to 2018. However, some characteristics of T. gondii infection in cattle remain uncertain, such as the role of meat intake in transmitting the parasite to humans. Most information regarding T. gondii infection among Brazilian cattle is limited to evaluations of the frequency of occurrence of antibodies. About 70% of the diagnoses of infection in these ruminants in Brazil are made via the indirect fluorescence antibody test (IFAT). Nevertheless, little is known about the population structure of this protozoan in cattle. It is necessary to expand the studies on toxoplasmosis in cattle, in order to better understand T. gondii infection in these animals and its implications for Brazilian public health.

Resumo Toxoplasma gondii é um protozoário apicomplexa de distribuição mundial prevalente em seres humanos e animais. A presente revisão objetiva elencar aspectos de importância relacionados à infecção por Toxoplasma gondii em bovinos no Brasil. A soroprevalência de anticorpos anti-T. gondii em bovinos do rebanho brasileiro varia de 1 a 89,1%, a depender da região avaliada, baseando-se em dados disponíveis de 1978 a 2018. Todavia, algumas características da infecção por T. gondii na espécie ainda são incertos, como o papel da ingestão da carne bovina na transmissão do parasita ao homem. A maior parte das informações relativas à infecção no rebanho nacional restringem-se a estudos de soroprevalência. Cerca de 70% do diagnóstico da infecção nesses ruminantes no Brasil é realizado por meio da Reação de Imunofluorescência Indireta (RIFI). Contudo, o conhecimento acerca da estrutura populacional do protozoário em bovinos ainda é limitado. Assim, é necessário ampliar os estudos sobre a toxoplasmose em bovinos, tendo em vista uma melhor compreensão da infecção na espécie, bem como de suas implicações para saúde pública brasileira.

Gallus gallus domesticus: immune system and its potential for generationof immunobiologics / Gallus gallus domesticus: sistema imunológico e seu potencial para geração de imunobiológicos

ABSTRACT: Gallus gallus domesticus' immune system is a promising tool for generation of antibody-based immunobiologics. Immunoglobulin y (IgY) is extracted from egg yolk and has equivalent functions to mammal's igg antibody. Avian immune system can be stimulated to produce a high-quality antibody repertoire. In this review, we present an overview of avian immune system emphasizing igy and its applications as an immunobiologic.

RESUMO: O sistema imunológico deGallus gallus domesticus é uma ferramenta promissora para a geração de imunobiológico a partir de anticorpos. A imunoglobulina Y (IgY) é extraída da gema do ovo e apresenta funções equivalentes ao anticorpo IgG dos mamíferos. O sistema imune aviário pode ser estimulado para produzir um repertório de anticorpos de alta qualidade. Nesta revisão apresentamos aspectos gerais do sistema imune aviário enfatizando o IgY e suas aplicações como um imunobiológico.

Production, characterization and applications for Toxoplasma gondii-specific polyclonal chicken egg yolk immunoglobulins.

BACKGROUND: Toxoplasma gondii may cause abortions, ocular and neurological disorders in warm-blood hosts. Immunized mammals are a wide source of hyperimmune sera used in different approaches, including diagnosis and the study of host-parasite interactions. Unfortunately, mammalian antibodies present limitations for its production, such as the necessity for animal bleeding, low yield, interference with rheumatoid factor, complement activation and affinity to Fc mammalian receptors. IgY antibodies avoid those limitations; therefore they could be an alternative to be applied in T. gondii model. METHODOLOGY/PRINCIPAL FINDINGS: In this study we immunized hens with soluble tachyzoite antigens of T. gondii (STAg) and purified egg yolk antibodies (IgY) by an inexpensive and simple method, with high yield and purity degree. IgY anti-STAg antibodies presented high avidity and were able to recognize a broad range of parasite antigens, although some marked differences were observed in reactivity profile between antibodies produced in immunized hens and mice. Interestingly, IgY antibodies against Neospora caninum and Eimeria spp. did not react to STAg. We also show that IgY antibodies were suitable to detect T. gondii forms in paraffin-embedded sections and culture cell monolayers. CONCLUSIONS/SIGNIFICANCE: Due to its cost-effectiveness, high production yield and varied range of possible applications, polyclonal IgY antibodies are useful tools for studies involving T. gondii.