IgY Antibodies from Birds: A Review on Affinity and Avidity.

IgY antibodies are found in the blood and yolk of eggs. Several studies show the feasibility of utilising IgY for immunotherapy and immunodiagnosis. These antibodies have been studied because they fulfil the current needs for reducing, replacing, and improving the use of animals. Affinity and avidity represent the strength of the antigen-antibody interaction and directly influence antibody action. The aim of this review was to examine the factors that influence the affinity and avidity of IgY antibodies and the methodologies used to determine these variables. In birds, there are few studies on the maturation of antibody affinity and avidity, and these studies suggest that the use of an adjuvant-type of antigen, the animal lineage, the number of immunisations, and the time interfered with the affinity and avidity of IgY antibodies. Regarding the methodologies, most studies use chaotropic agents to determine the avidity index. Studies involving the solution phase and equilibrium titration reactions are also described. These results demonstrate the need for the standardisation of methodologies for the determination of affinity and avidity so that further studies can be performed to optimise the production of high avidity IgY antibodies.

Avian anti-HBV immunoglobulin: New tool to improve hepatitis B diagnosis methods.

Immunoglobulin Y (IgY) could be used in serological diagnosis focused on several infectious agents. This study aims to produce IgY anti-hepatitis B virus surface antigen (anti-HBs) and to assess its use in enzyme immunoassays. Antibodies were produced by immunizing chickens with Hepatitis B vaccine associated (group A), or not, with adjuvant CpG-ODN (group B). Eggs were collected for 20 weeks, yolks were purified based on using polyethylene glycol and affinity chromatography. IgY anti-HBs was featured based on SDS-PAGE and Western Blot techniques. Total protein concentration was measured through spectrophotometry. In-house ELISA used to detect HBsAg was developed based on using IgG/HRP conjugate and IgY-anti-HBs sensitized microplates. Thus, IgY anti-HBs were confirmed through molecular pattern based on SDS-PAGE, whereas specificity of anti-HBs was confirmed through Western Blot. Mean total protein reached 3.27 ± 3.00 mg/mL and 3.11 ± 3.12 mg/mL in groups A and B, respectively. In-house ELISA was developed based on using a panel of HBV positive and negative serum samples; it recorded 100 % sensitivity and 78.9 % specificity to detect HBsAg. In conclusion, it was possible producing anti-HBs IgY by immunizing chickens with HBV vaccine; this molecule could be used as capture antibody to help detecting HBsAg in-house ELISA.

Production of IgY against iron permease Ftr1 from Candida albicans and evaluation of its antifungal activity using Galleria mellonella as a model of systemic infection.

Candida albicans is one of the leading pathological agents of mucosal and deep tissue infections. Considering that the variety of antifungals is restricted and that toxicity limits their use, immunotherapies against pathogenic fungi have been viewed as alternatives with reduced adverse effects. In this context, C. albicans has a protein used to capture iron from the environment and the host, known as the high-affinity iron permease Ftr1. This protein may be a new target of action for novel antifungal therapies, as it influences the virulence of this yeast. Thus, the aim of the present study was to produce and conduct the biological characterization of IgY antibodies against C. albicans Ftr1. Immunization of laying hens with an Ftr1-derived peptide resulted in IgY antibodies extracted from egg yolks capable of binding to the antigen with high affinity (avidity index = 66.6 ± 0.3%). These antibodies reduced the growth and even eliminated C. albicans under iron restriction, a favorable condition for the expression of Ftr1. This also occurred with a mutant strain that does not produce Ftr1 in the presence of iron, a circumstance in which the protein analog of iron permease, Ftr2, is expressed. Furthermore, the survival of G. mellonella larvae infected with C. albicans and treated with the antibodies was 90% higher than the control group, which did not receive treatment (p < 0.0001). Therefore, our data suggest that IgY antibodies against Ftr1 from C. albicans can inhibit yeast propagation by blocking iron uptake.

Production and Evaluation of Chicken Egg Yolk Immunoglobulin (IgY) against Human and Simian Rotaviruses.

Producing specific antibodies in chickens is an attractive approach for diagnosis or therapeutic applications. Besides the high immunoglobulin Y (IgY) yield transferred to the egg yolk and its suitability for large-scale production, such an approach is more bioethical for animal maintenance. The IgY technology offers new possibilities for application in human and veterinary diagnostics and therapeutics, including strategies for treating severe intestinal diseases in children, particularly in emerging countries. Herein, we describe the production and purification of polyclonal antibodies against rotavirus group A (RVA) in immunised hens aiming at its application in prophylaxis and treatment of rotavirus-induced diarrhoea. For this purpose, we inoculated Rhodia laying chickens (Gallus gallus domesticus) with two or three doses of RVA combined with adjuvants or only adjuvants (control group). As the egg-laying period began, the yolk protein purification processes yielded a high concentration of specific IgY, the highest titre resulting from the group of hens that received three doses of the immunogen. The purified IgY blocked the functional activity of RVA in MA-104 cells, thus confirming the neutralisation ability. Therefore, anti-RVA IgY could be a promising candidate for pre- and post-exposure prevention or treatment of rotavirus-induced diarrhoea.

Immunotherapy With Egg Yolk Eimeria sp.-Specific Immunoglobulins in SPF Leghorn Chicks Elicits Successful Protection Against Eimeria tenella Infection.

Avian coccidiosis is the first to most economically important parasite disease affecting poultry industries worldwide. Current prevention measures are largely based upon prophylactic chemotherapy supplemented by the application of live attenuated or wild-type parasite vaccines. However, the rising appearance of drug resistance, consumer's concern for antibiotics use in poultry production and higher manufacturing cost of live vaccines has driven to adopt new technologies aimed at increasing animal health and production efficiency. Supplementing chickens with egg yolk Eimeria sp.-specific immunoglobulins can be a viable alternative to avoid severe outbreaks of the disease. Twelve-week-old SPF White Leghorn chickens were experimentally infected with a large dose of E. tenella. During the prepatent period, the birds were supplemented by oral gavage with 60 or 120 mg/bird of hyperimmune egg yolk Eimeria species-specific immunoglobulins Y (Supracox®, SC) on a daily basis. The animals were euthanized 7 days post-infection (PI) and their passive immune protection was evaluated. Birds treated with 120 mg/bird of SC showed more viability, increased body weight gain (BWG), a normal hematocrit level (HCT), reduced oocyst output per gram of feces (OPG) or cecal tissue (OPGC), and fewer cecal lesions compared to the untreated infected (UI) control group. Birds supplemented with 60 mg/bird of SC did not show any significant difference on BWG, HCT, OPG, OPGC, and cecal lesion score when compared with the UI group. An ELISA test of the SC showed a weak cross-reactivity of IgY toward two asexual zoite stages of E. tenella. Western blot analysis of the sporozoite with SC showed few antigens barely recognized, while more stained bands were detected in the merozoite (≈82, ≈60, ≈54, ≈40, ≈38, ≈27.5, and ≈13 kDa). Oral immunotherapy using egg yolk polyclonal IgYs against Eimeria sp. represents an effective and natural resource against severe E. tenella infection favoring the gradual withdrawal of the anticoccidial drugs and antibiotics.

Exploring the potential usefulness of IgY for antiviral therapy: A current review.

Immunoglobulin yolk (IgY) is therapeutic antibodies presented in yolk eggs of birds, reptiles, and amphibians. These proteins produced by the immune system of the animal, are capable of neutralizing antigenic molecules, including viral antigens, fulfilling a role in the body defense. The specificity of these antibodies and the facility for their production, make these molecules capable of being used as tools for diagnosis and immunotherapy. Regarding this last aspect, it is common knowledge that the field of virology, is racing against time in the development of new drugs and vaccines to try to contain pandemics and local epidemics and, in counterproposal, avian antibodies are neutralizing molecules that can help in the control and spread of disease. These molecules have been explored for years and currently chicken eggs are produced in large quantities from the animal's immunization against a specific pathogen. Thus, on this subject, this review made a survey of these researches and presents a summary of all the successful cases and perspectives in the use of IgYs as tools for viral immunization.

Inclusion of IgY in a dog's diet has moderate impact on the intestinal microbial fermentation.

AIMS: This study aimed to evaluate the impact of immunoglobulin Y (IgY) in a diet on the systemic health and the gastrointestinal tract (GIT) of dogs. METHODS AND RESULTS: Sixteen healthy 11-month-old Beagle dogs were distributed at random (eight animals per treatment) in two treatments groups: control (0 g kg-1 IgY) and test (2 g IgY per day). The animals were evaluated on days 0 and 40 for a complete blood count (CBC) and biochemical profiles (ALT, ALP, creatinine and urea). Faecal samples were collected from days 35 to 40 to measure nutrient digestibility, faecal characteristics, sialic acid, intestinal microbiota composition and microbial metabolites. The CBC, biochemical profiles, apparent nutrient digestibility and faecal characteristics did not differ between the two treatment groups (P > 0·05). Dog faeces that received IgY were characterized by lower sialic acid and n-valeric concentration, as well as an increase in n-butyric concentration, in contrast to dogs fed a diet without IgY (P < 0·05). The other microbial faecal metabolites did not differ between the two treatment groups (P > 0·05). There tended to be an increase in the copy number of Clostridium cluster XIVa (Clostridium coccoides group) in the IgY group in contrast to the control group (P = 0·07). The other bacteria analysed did not differ between the treatment groups (P > 0·05). The colonic pH in the IgY group was lower than in control group (P < 0·05). CONCLUSIONS: The addition of IgY in the diet of healthy dogs maintains the microbial balance and has an interesting effect on microbial metabolites. SIGNIFICANCE AND IMPACT OF THE STUDY: The use of IgY, antibodies produced by laying hens, in animal feed is an alternative for the prevention and treatment of intestinal diseases in companion animals.

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.

Passive transfer of immunity in dairy calves with additional consumption of immunoglobulin through colostrum supplement: effects in health and performance / Saúde, desempenho e transferência de imunidade passiva em bezerras com consumo adicional de imunoglobulinas através de suplemento de colostro

The aim of this study was to evaluate the effects of additional consumption of immuneglobulins associated with high quality colostrum in health and performance of dairy calves. After birth, 80 females were randomly assigned to two treatments: MC) high quality colostrum, supplied in a volume corresponding to 15% of birth weight; and MC+S) high quality colostrum (15% of birth weight) + colostrum supplement. Blood parameters were not affected by the additional supply of immune globulins (Ig) by colostrum supplement feeding. The concentrate and total dry matter intakes were not affected by the administration of colostrum supplementation. The additional intake of Ig through the colostrum supplement did not affect the performance or feed efficiency of calves; however, animals doubled their birth weight at the end of the period, as occurred with MC fed calves. Regarding the health, additional supply of Ig did not affect the number of days with diarrhea, days with fever or medicated days. The additional intake of Ig via colostrum supplement in combination with high quality maternal colostrum have not improved immunity or affected the performance and health of dairy calves.(AU)

O objetivo do presente experimento foi avaliar o efeito do consumo adicional de imunoglobulinas através do fornecimento de suplemento de colostro associado a colostro materno de alta qualidade na transferência de imunidade passiva, saúde e desempenho de bezerras da raça Holandesa recém-nascidas. Após o nascimento, 80 fêmeas foram distribuídas aleatoriamente em dois tratamentos: (CM) colostro materno de alta qualidade, fornecido em volume correspondente a 15% do peso ao nascer (PN); e (CM+S) colostro materno de alta qualidade (15% PN) + suplemento de colostro. Os parâmetros sanguíneos não foram afetados pelo fornecimento adicional de imunoglobulinas (Ig) através da associação de suplemento com colostro materno. O consumo de concentrado e o consumo total de matéria seca (MS) não foram afetados pela administração do suplemento de colostro. O consumo adicional de Ig através do fornecimento de suplemento de colostro também não afetou o desempenho e a eficiência alimentar das bezerras, entretanto os animais dobraram o peso ao nascer ao final do experimento, assim como aqueles que receberam CM. Em relação à saúde, o fornecimento adicional de Ig não afetou os dias com diarréia, dias com febre ou dias medicados. O consumo adicional de Ig através do fornecimento de suplemento de colostro em associação ao colostro materno de alta qualidade não melhorou a imunidade, bem como não afetou o desempenho ou a saúde das bezerras.(AU)

Passive transfer of immunity in dairy calves with additional consumption of immunoglobulin through colostrum supplement: effects in health and performance / Saúde, desempenho e transferência de imunidade passiva em bezerras com consumo adicional de imunoglobulinas através de suplemento de colostro

The aim of this study was to evaluate the effects of additional consumption of immuneglobulins associated with high quality colostrum in health and performance of dairy calves. After birth, 80 females were randomly assigned to two treatments: MC) high quality colostrum, supplied in a volume corresponding to 15% of birth weight; and MC+S) high quality colostrum (15% of birth weight) + colostrum supplement. Blood parameters were not affected by the additional supply of immune globulins (Ig) by colostrum supplement feeding. The concentrate and total dry matter intakes were not affected by the administration of colostrum supplementation. The additional intake of Ig through the colostrum supplement did not affect the performance or feed efficiency of calves; however, animals doubled their birth weight at the end of the period, as occurred with MC fed calves. Regarding the health, additional supply of Ig did not affect the number of days with diarrhea, days with fever or medicated days. The additional intake of Ig via colostrum supplement in combination with high quality maternal colostrum have not improved immunity or affected the performance and health of dairy calves.

O objetivo do presente experimento foi avaliar o efeito do consumo adicional de imunoglobulinas através do fornecimento de suplemento de colostro associado a colostro materno de alta qualidade na transferência de imunidade passiva, saúde e desempenho de bezerras da raça Holandesa recém-nascidas. Após o nascimento, 80 fêmeas foram distribuídas aleatoriamente em dois tratamentos: (CM) colostro materno de alta qualidade, fornecido em volume correspondente a 15% do peso ao nascer (PN); e (CM+S) colostro materno de alta qualidade (15% PN) + suplemento de colostro. Os parâmetros sanguíneos não foram afetados pelo fornecimento adicional de imunoglobulinas (Ig) através da associação de suplemento com colostro materno. O consumo de concentrado e o consumo total de matéria seca (MS) não foram afetados pela administração do suplemento de colostro. O consumo adicional de Ig através do fornecimento de suplemento de colostro também não afetou o desempenho e a eficiência alimentar das bezerras, entretanto os animais dobraram o peso ao nascer ao final do experimento, assim como aqueles que receberam CM. Em relação à saúde, o fornecimento adicional de Ig não afetou os dias com diarréia, dias com febre ou dias medicados. O consumo adicional de Ig através do fornecimento de suplemento de colostro em associação ao colostro materno de alta qualidade não melhorou a imunidade, bem como não afetou o desempenho ou a saúde das bezerras.

Phagolysosomal activity of macrophages in Nile tilapia (Oreochromis niloticus) infected in vitro by Aeromonas hydrophila: Infection and immunotherapy.

The biochemical mechanisms involved in phagocytosis and the intracellular survival of Aeromonas hydrophila (Ah) in host macrophages (MΦs) are complex processes that affect infection success or failure. Thus, in the present study, we described the in vitro infection of Nile tilapia MΦs by a homologous bacterium and tested the effects of anti-A. hydrophila immunoglobulin Y (IgY) on the phagolysosomal activity and intracellular survival of the pathogen. The anti-Ah IgY modulated lysosomal acid phosphatase (LAP) activity as well as the production of reactive oxygen intermediates (ROIs) and nitric oxide (NO), thereby potentiating phagocytosis and the elimination of Ah. Thus, we assume that the specific IgY had a beneficial effect on infection control and postulated the use of the Nile tilapia MΦs as an important in vitro experimental model for the functional and therapeutic study of Ah infection.

Passive immune transfer, health, pre-weaning performance, and metabolism of dairy calves fed a colostrum supplement associated with medium-quality maternal colostrum

The objective of this study was to evaluate passive immunity transfer, health, performance, and metabolism of Holstein calves fed colostrum supplement associated with medium-quality colostrum. After birth, calves were blocked according to birth weight and date and distributed into the following treatments: high-quality colostrum (> 50 mg of Ig/mL; n = 15; 150 g kg−1 BW; positive control group); medium-quality colostrum (30-40 mg of Ig/mL; n = 14; 150 g kg−1 BW), and medium-quality colostrum (30-40 mg of Ig/mL; n = 15; 150 g kg−1 BW) + colostrum supplement (15 mL) given with the colostrum. Colostrum was given within the first 12 h of life in two meals by nipple bottle, and colostrum replacer was administered by a blister syringe. Blood samples were taken every 12 h up to 48 h of life for total serum protein (TSP) evaluation. After colostrum feeding, calves were fed 4 L of transition milking, split in two meals for a period of one to four days and received milk replacer thereafter. Calves were individually housed, with free access to water and concentrate and bucket-fed 6 L/d of milk replacer up to the sixth week of life, when they received 4 L/d until weaning, with eight weeks. Colostrum feeding protocol affected the TSP concentration in the first 48 h of life, while the concentrations of albumin, glucose, ß-hydroxybutyrate, γ-glutamyl transferase, and alkaline phosphatase were not affected. During the milk-feeding period, the concentrate and total dry matter intake were not affected by the colostrum protocol, but increased as animals aged. Colostrum-feeding protocol did not affect performance or health of calves. Feeding colostrum supplement associated with medium-quality colostrum had no effect on passive immune transfer, performance, nor on the metabolism during the liquid-feeding phase.(AU)

Use of chicken immunoglobulin Y in general virology.

Immunoglobulin Y (IgY), an antibody present in birds, reptiles, and amphibians, is actively transported from the serum to egg yolks, where it is stored in large quantities. The use of chicken polyclonal IgY instead of mammalian IgG antibodies for biomedical applications has ethical and economic advantages, such as the lack of a need for animal bleeding because the antibodies are extracted from eggs after hen immunization and the low cost of the production and purification methods. This article reviews the latest IgY applications in diagnostic virology and the therapeutic use of IgY in viral gastroenteritis.

Gut-Associated Lymphoid Tissue: A Key Tissue Inside the Mucosal Immune System of Hens Immunized with Escherichia coli F4.

Immunoglobulin Y (IgY) is the predominant antibody found in hen's (Gallus domesticus) egg yolk. This antibody, developed against several microorganisms in hen egg yolk, has been successfully used as an alternative to immunoglobulins from mammals for use in immunodiagnostics and immunotherapy. Enteropathogenic Escherichia coli (E.coli) F4 is the main etiological agent associated with swine neonatal diarrhea, and it causes notable economic losses in swine production. The aim of the present study was to evaluate the relationship between humoral immune response and the activation of gut-associated lymphoid tissue (GALT) in laying hens intramuscularly immunized with E. coli F4. Adult laying Shaver hens were immunized with a bacterin based on an inactivated lysate E. coli F4 strain that was originally isolated from neonatal piglet diarrhea, following a recommended schedule. The percentage of B lymphocytes in blood and spleen homogenates was determined by flow cytometry. Villi histomorphometry and the size of germinal centers (GC) activated in GALT and the spleen were measured in histological samples either stained with hematoxylin/eosin or through immunofluorescence. Antibody and isotype-specific antibodies in serum and egg yolk were measured using indirect enzyme-linked immunosorbent assay (ELISA). Secretory and serum immunoglobulin A (IgA) were measured by ELISA tests. Laying hen with intramuscular immunization with E. coli F4 lysate, activated both mucosal and systemic protection. Mucosal protection was provided through B lymphocytes, and most of them were activated on Peyer's patches and esophageal tonsils, in GALT. Furthermore, increased B lymphocyte number in the lamina propria of the gut, and increased intraepithelial plasmatic cell number, produced high levels of mucosal IgA. Activated B lymphocytes interacted with absorptive cells, immune cells, and microbiota in the gut, producing signals that were translated into a powerful physical defense by producing a greater volume of mucin from an increased number of goblet cells. Systemic protection was provided through B lymphocyte activation of spleen GC, which produced hugely specific IgY serum levels. One week later, this specific IgY was deposited in the yolk. This suggests that GALT is a key immunologic tissue inside the mucosal immune system, acting as the "command center" for humoral reaction.

Development and characterization of IgY antibodies against synthetic peptides from Brucella abortus OMP25 and BP26 proteins / Desarrollo y caracterización de anticuerpos IgY contra péptidos sintéticos de las proteínas OMP25 y BP26 de Brucella abortus

Brucellosis is a zoonose produced by bacterial species from the Brucella genus. Its isolation and identification in food using classical microbiological techniques is not practical due to its slow growth rate. Therefore, it is necessary to establish fast and specific methods for the detection of the bacteria in food. The goal of this work was the production and characterization of monospecific polyclonal antibodies in chicken (IgY) against synthetic peptides from Brucella abortus OMP25 and BP26 proteins, suitable for an antigen-capture assay. Conformational as well as antigenic predictions were performed using the ANTHEPROT package. Chemical synthesis was carried out by the multiple manual synthesis using the t-boc strategy. The peptides were used as antigens for the preparation of polyclonal antibodies in chicken. Experimental animals produced specific antibodies against the OMP25 and BP26 peptides constructs determined by ELISA and MABA assays showing correspondence between the predictive study and the immunogenicity obtained in chicken. The IgY proved to be able to recognize B. abortus by MABA assays. The binding activity and specificity of antibodies was determined by Western blot with cell extract from B. abortus. In this study, we demonstrated that OMP25 and BP26 peptides constructs are good candidates for production of specific IgY antipeptide antibodies capable of recognizing proteins from sonicated B. abortus strain S19, indicating the potential usefulness of the IgY antibody for development of immunoassays for detection of Brucella abortus.

La brucelosis es una zoonosis producida por especies del género Brucella. El aislamiento e identificación de la bacteria en alimentos usando las técnicas clásicas de microbiología no es práctico debido a su lenta tasa de crecimiento. Por lo tanto, es necesario establecer métodos rápidos para la detección de la bacteria en alimentos. En el presente trabajo se desarrollaron y caracterizaron anticuerpos policlonales monoespecíficos en gallinas (IgY) contra péptidos sintéticos de las proteínas OMP25 y BP26 de Brucella abortus, que puedan ser utilizados en un ensayo de captura. Para ello, se realizaron estudios conformacionales y de predicción de epítopes en la selección de los péptidos, los cuales se utilizaron como antígenos para la producción de las IgY. Los animales desarrollaron anticuerpos específicos contra los péptidos, mostrando correspondencia entre los estudios predictivos y la inmunogenicidad obtenida. Las IgY reconocieron a B. abortus en un ensayo de MABA y la actividad de unión y especificidad fue determinada por western blot con extracto celular de B. abortus. En este estudio, demostramos que los péptidos de las proteínas OMP25 y BP26 de B. abortus son buenos candidatos para la producción de anticuerpos IgY especificos capaces de reconocer proteínas de extracto de B. abortus cepa S19, indicando el potencial uso de anticuerpos IgY para el desarrollo de inmunoensayos para la detección de Brucella abortus.

Immunological identification of a cAMP-dependent protein kinase regulatory subunit-like protein from the Trypanosoma equiperdum TeAp-N/D1 isolate.

Polyclonal immunoglobulin Y (IgY) antibodies were produced in chicken eggs against the purified R(II)-subunit of the cAMP-dependent protein kinase (PKA) from pig heart, which corresponds to the Sus scrofa R(II)α isoform. In order to evaluate whether Trypanosoma equiperdum possessed PKA R-like proteins, parasites from the Venezuelan TeAp-N/D1 strain were examined using the generated anti-R(II) IgY antibodies. Western blot experiments revealed a 57-kDa polypeptide band that was distinctively recognized by these antibodies. Likewise, polyclonal antibodies raised in mice ascites against the recombinant T. equiperdum PKA R-like protein recognized the PKA R(II)-subunit purified from porcine heart and the recombinant human PKA R(I)ß-subunit by immunoblotting. However, a partially purified fraction of the parasite PKA R-like protein was not capable of binding cAMP, implying that this protein is not a direct downstream cAMP effector in T. equiperdum. Although the function of the S. scrofa PKA R(II)α and the T. equiperdum PKA R-like protein appear to be different, their cross-reactivity together with results obtained by bioinformatics techniques corroborated the high level of homology exhibited by both proteins. Moreover, its presence in other trypanosomatids suggests an important cellular role of PKA R-like proteins in parasite physiology.

Using immunoglobulin Y as an alternative antibody for the detection of hepatitis A virus in frozen liver sections

An increasing amount of research has been conducted on immunoglobulin Y (IgY) because the use of IgY offers several advantages with respect to diagnostic testing, including its easy accessibility, low cost and translatability to large-scale production, in addition to the fact that it can be ethically produced. In a previous work, immunoglobulin was produced and purified from egg yolks (IgY) reactive to hepatitis A virus (HAV) antigens. In the present work, this anti-HAV-specific IgY was used in an indirect immunofluorescence assay to detect viral antigens in liver biopsies that were obtained from experimentally infected cynomolgus monkeys. Fields that were positive for HAV antigen were detected in liver sections using confocal microscopy. In conclusion, egg yolks from immunised hens may be a reliable source for antibody production, which can be employed for immunological studies.

Adsorption of immunoglobulin Y in supermacroporous continuous cryogel with immobilized Cu(2+) ions.

The influence of temperature, pH and ionic strength on the adsorption of Immunoglobulin Y (IgY) in IDA-Cu(2+) cryogel system was studied by batch equilibrium measurements. The adsorptive equilibrium data were obtained at 17 and 27°C, pH 5.0 and 6.5, and at ionic strength of 50 and 200mmolL(-1) NaCl. Langmuir, Freundlich and Langmuir-Freundlich models were fitted to equilibrium data, while the enthalpy of adsorption of IgY in IDA-Cu(2+) cryogel system was calculated through Van't Hoff analysis. The binding of IgY on cryogel was stronger at 27°C and lowest pH and ionic strength values, with apparent maximum adsorption capacity of 27mgg(-1). The adsorption of protein in the resin was spontaneous in all analyzed cases. The results provide valuable information to enable the improvement of IgY purification processes.

Avian IgY antibodies: characteristics and applications in immunodiagnostic / Anticorpos IgY aviário: características e aplicações em imunodiagnóstico

Immunoglobulin Y (IgY) is the major antibody isotype in birds, reptiles, amphibia, and lungfish, playing a similar biological role as mammal IgG. Due to its phylogenetic distance, immune diversification and presence in the egg yolk, IgY provide a number of advantages in immunodiagnostic compared to IgG from mammals. Moreover, IgY production is in agreement with international efforts to reduce, refine and if possible, to replace animals in experimentation, contributing substantially in favor of animal welfare. This article presents an overview about structural and functional features, production and applications of IgY in immunodiagnostic, as well as the advantages of chicken antibodies use.

A imunoglobulina Y (IgY) é a classe de anticorpos de maior importância em aves, répteis, anfíbios e peixes pulmonados, desempenhando um papel semelhante a IgG de mamíferos. Devido a sua distância filogenética, mecanismos de diversificação imune e presença na gema do ovo, IgY proporciona uma série de vantagens em imunodiagnóstico, quando comparada a IgG de mamíferos. Além disso, esse método alternativo de produção de anticorpo está de acordo com os esforços internacionais para reduzir, refinar e, se possível, substituir animais em experimentação, contribuindo substancialmente a favor do bem-estar animal. Este artigo apresenta uma revisão sobre as características estruturais e funcionais da IgY, bem como os métodos de produção, vantagens e aplicações em imunodiagnóstico, além das vantagens da sua utilização.

Avian IgY antibodies: characteristics and applications in immunodiagnostic / Anticorpos IgY aviário: características e aplicações em imunodiagnóstico

Immunoglobulin Y (IgY) is the major antibody isotype in birds, reptiles, amphibia, and lungfish, playing a similar biological role as mammal IgG. Due to its phylogenetic distance, immune diversification and presence in the egg yolk, IgY provide a number of advantages in immunodiagnostic compared to IgG from mammals. Moreover, IgY production is in agreement with international efforts to reduce, refine and if possible, to replace animals in experimentation, contributing substantially in favor of animal welfare. This article presents an overview about structural and functional features, production and applications of IgY in immunodiagnostic, as well as the advantages of chicken antibodies use.(AU)

A imunoglobulina Y (IgY) é a classe de anticorpos de maior importância em aves, répteis, anfíbios e peixes pulmonados, desempenhando um papel semelhante a IgG de mamíferos. Devido a sua distância filogenética, mecanismos de diversificação imune e presença na gema do ovo, IgY proporciona uma série de vantagens em imunodiagnóstico, quando comparada a IgG de mamíferos. Além disso, esse método alternativo de produção de anticorpo está de acordo com os esforços internacionais para reduzir, refinar e, se possível, substituir animais em experimentação, contribuindo substancialmente a favor do bem-estar animal. Este artigo apresenta uma revisão sobre as características estruturais e funcionais da IgY, bem como os métodos de produção, vantagens e aplicações em imunodiagnóstico, além das vantagens da sua utilização.(AU)