Anticorpos IgY anti-larvas de Ancylostoma ceylanicum aplicados no imunodiagnóstico da ancilostomíase humana e reatividade cruzada com a estrongiloidíase

Abstract

The hookworm infection is considered a neglected tropical disease (NTD) caused by nematodes belonging to Ancylostomatidae family. Approximately 740 million people worldwide are infected with this parasite. Difficulties in the diagnosis may be related to cross-reactivity with other parasites, due to the antigenic complexity and phylogenetic proximity to some species. In order to improve the diagnosis of human hookworm infection, this study enabled the unprecedented production of specific IgY antibodies against Ancylostoma ceylanicum, highlighting the fact that the method is economically feasible, reproducible and has high antibodies profitability. The saline extract of A. ceylanicum filarial larvae was evaluated in one-dimensional electrophoresis to characterize the protein profile and chickens immunization. Samples of purified anti-larvae of A. ceylanicum IgY showed concentrations of 8.370 μg/ml and 4.000 μg/ml. The process of IgY antibodies purification was confirmed by polyacrylamide gel electrophoresis 8% (SDS-PAGE). The pure yolks showed protein bands with apparent molecular weight slightly below ≤ 200, 110, 80, 50 and 20 kDa. The fractions P1 and P2, and the HPLC purified sample showed bands with molecular weights somewhat below ≤ 200 kDa, identifying the specific IgY. The peaks of the production of A. ceylanicum antibodies IgY anti-larvae occurred at 6th, 8th and 16th weeks after the immunizations. The higher avidity was detected at 15th week with 67% content. The antibodies were capable of detecting immunocomplexes in 16.6% (5/30) of serum samples from infected individuals with hookworm, 10% (3/30) of serum samples from individuals with strongyloidiasis, 6.7% (2/30) in serum samples with other parasitosis and 0% in negative cases. It is concluded that the A. ceylanicum IgY antibody anti-larvae can be considered as a possible diagnostic tool for hookworm infection, but more studies are needed to improve the techniques.