Anticorpos IgY específicos para rotavírus do grupo A. Uma abordagem terapêutica para rotavirose em Macaca fascicularis / Specific IgY antibodies to rotavirus group A. A therapeutic approach for rotavirus disease in macaca fasciculares

A produção de anticorpos em aves imunizadas seguida da extração desses anticorpos da gema dos ovos (IgY), tem atraído o interesse da comunidade científica, como pode ser demonstrado pelo aumento significativo da literatura sobre a IgY. [...] Destaca-se que a tecnologia da IgY oferece novas possibilidades de aplicação em imunoterapia e métodos de diagnóstico, tanto para aplicação humana quanto veterinária, incluindo estratégias de tratamentode doenças intestinais graves em crianças, particularmente em países pobres. Neste presente estudo, objetivou-se avaliar a eficiência terapêutica da IgY utilizando macacos cynomolgus (Macaca fascicularis) jovens desafiados com o rotavírus do grupo A (RVA) humano, a maior causa de morbidade e mortalidade de crianças em todo o mundo, especialmente em países em desenvolvimento. Para esta proposta, anticorpos IgY específicos contra o RVA foram produzidos em aves, purificados por polietileno glicol, caracterizados por eletroforese em gel depoliacrilamida, western blotting e um teste de neutralização em cultura de células (MA-104). Este experimento preliminar rendeu uma suspensão altamente concentrada de IgY específica antirotavírus(IgY anti-RVA) (média de 37 mg/mL). O macaco cynomolgus foi estabelecido como modelo de infecção experimental após uma única administração de suspensão de rotavírus humano (3,1x106FFU/mL) por sonda gástrica. Os animais foram acompanhados durante onze dias, sendo observadas as manifestações clínicas, cargas virais sérica e fecal, hematologia e dosagem de eletrólitos séricos...

The production of antibodies in chickens and the extraction of specific antibody suspensions fromegg yolk (IgY) are increasingly attracting the interest of the scientific community, asdemonstrated by the significant growth of the IgY literature. [...] Of note, the IgY-technology offersnew possibilities for application in human and veterinary diagnostics and therapeutics, includingstrategies for the treatment of severe intestinal diseases in children, particularly in poor countries.In this study, we aimed to evaluate the therapeutic efficacy of the IgY by using youngcynomolgus monkeys (Macaca fascicularis) challenged with human rotavirus group A (RVA), amajor cause of morbidity and mortality in children worldwide, especially in developing countries.For this purpose, specific IgY antibodies against RVA were produced in hens, purified bypolyethylene glycol, characterized by polyacrylamide gel electrophoresis, western blotting and aneutralization assay in a cell culture system (MA-104). This preliminary experiment has yielded ahigh concentrated suspension of anti-rotavirus specific IgY (anti-RVA IgY) (average 37 mg/ml).The cynomolgus experimental infection model was established after a single administration of ahuman rotavirus suspension (3.1x106FFU/ml) by oral gavage. The confined animals werefollowed during a period of eleven days, observed for clinical signs, measurement of serum andfaecal viral load, and evaluation of hematology and serum electrolytes. The main clinical sign(observed in two of the seven inoculated monkeys) was diarrhea associated with a decrease inserum potassium during three days, followed by recovery...

An immunoenzymatic assay for the diagnosis of hepatitis A utilising immunoglobulin Y

The detection of anti-hepatitis A virus (HAV) antibody levels by diagnostic kits in the convalescent period of disease generally use immunoglobulin G (IgG), which is expensive. An alternative to IgG is immunoglobulin Y (IgY), an immunoglobulin antibody encountered in birds and reptiles. The aim of this study was to develop a competitive immunoenzymatic assay to measure total anti-HAV antibody levels using anti-HAV IgY as the capture and conjugated immunoglobulins. For this purpose, anti-HAV IgY was conjugated to horseradish peroxidase (HRP) and the optimal dilution of HRP-conjugated antibodies was evaluated to establish the competitive immuneenzymatic assay. The results obtained from our "in-house" assay were plotted on a receiver operator curve, which showed a sensitivity of 95% and a specificity of 98.8%, demonstrating that a competitive anti-HAV IgY immunoenzymatic assay developed "in house" could be used as an alternative to commercial assays that utilise IgG.