Egg yolk immunoglobulin Y as a promising tool to detect immune complexes in neurocysticercosis serum samples.

BACKGROUND: Neurocysticercosis (NCC) is a neglected tropical disease and its diagnosis is still a challenge due to non-specific manifestations. Neuroimaging techniques are used in the diagnosis of NCC, however, due to the high cost of these methods and the advantages presented in the use of immunological tests, such as ease of performance and satisfactory results, immunoassays are commonly used to detect antibodies against Taenia sp. antigens. The aim of the present study was to produce, characterize and apply specific polyclonal immunoglobulin Y (IgY) anti-Taenia crassiceps extracted from egg yolk of hens immunized with T. crassiceps metacestodes. METHODS: Indirect enzyme-linked immunosorbent assay (ELISA), avidity ELISA, immunoblotting and indirect immunofluorescence tests were performed for characterization of IgY antibodies. Diagnostic performance was verified by ELISA for immune complex detection testing 90 serum samples. RESULTS: Values of sensitivity, specificity, positive and negative likelihood ratios (LR+/LR-) and area under the curve (AUC) were calculated and presented the following results: sensitivity 83.3%, specificity 96.7%, AUC 0.966, LR+ 25.0 and LR- 0.17. CONCLUSIONS: Results of this pioneering and innovative study demonstrate that anti-T. crassiceps IgY antibodies present potential applicability and can be used as an efficient tool in human NCC serodiagnosis.

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.

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.

Serological cross-reactivity between Strongyloides venezuelensis and Syphacia muris in Wistar rats (Rattus norvegicus).

One of the problems frequently faced in laboratory facilities is the possibility of the natural parasitic infection of lab animals, which can interfere with biomedical research results. The present study aimed to evaluate cross-reactivity among serum samples from Wistar rats (Rattus norvegicus) naturally infected with Syphacia muris and experimentally infected with Strongyloides venezuelensis. Forty rats were divided into four groups of ten animals each. Parasite load was evaluated by quantifying the adult worms from both helminthes species recovered from the intestines and the S. venezuelensis eggs eliminated in feces. Serological cross-reactivity by parasite-specific IgG detection was tested via enzyme linked immunosorbent assay (ELISA), immunofluorescence antibody test (IFAT) and immunoblotting. The results demonstrated that the quantity of S. venezuelensis eliminated eggs and parthenogenetic females decreased significantly in cases of co-infection with S. muris. ELISA revealed 100% cross-reactivity of serum samples from both species against the opposing antigen. IgG cross-reactivity was confirmed by IFAT using tissue sections of S. venezuelensis larvae and adult S. muris. Immunoblotting showed that IgG antibodies from the sera of animals infected with S. muris recognized eight antigenic bands from S. venezuelensis saline extract and that IgG antibodies from the sera of animals infected with S. venezuelensis recognized seven bands from S. muris saline extract. These results demonstrate the serological cross-reactivity between S. muris and S. venezuelensis in infected rats.

Sarchophagid flies (Insecta, Diptera) from pig carcasses in Minas Gerais, Brazil, with nine new records from the Cerrado, a threatened Neotropical biome

Sarchophagid flies (Insecta, Diptera) from pig carcasses in Minas Gerais, Brazil, with nine new records from the Cerrado, a threatened Neotropical biome. The diversity of the Sarcophagidae fauna of the Cerrado biome, also know as the Brazilian Savanna, is still underestimated. In this research we collected flies in the state of Minas Gerais, Brazil, during a Forensic Entomology experiment. Samples were collected throughout the decomposition process of domestic pig (Sus scrofa Linnaeus) carcasses, and the experiments were conducted in areas of pasture and semideciduous forest. A total of 85,694 adult flesh flies belonging to 57 species were collected from all carcasses. New records for nine species of Sarcophaginae are provided, including the first record of Blaesoxipha (Acridiophaga) caridei (Brèthes, 1906) to Brazil, and new occurrences of the following species for the Cerrado and/or for the state of Minas Gerais: Blaesoxipha (Acanthodotheca) acridiophagoides (Lopes & Downs, 1951), Malacophagomyia filamenta (Dodge, 1964), Nephochaetopteryx orbitalis (Curran & Walley, 1934), Nephochaetopteryx cyaneiventris Lopes, 1936, Nephochaetopteryx pallidiventris Townsend, 1934, Oxysarcodexia occulta Lopes, 1946, Ravinia effrenata (Walker, 1861) and Sarcophaga (Neobellieria) polistensis (Hall, 1933).