Avaliação de novos antígenos quiméricos recombinantes no diagnóstico da leishmaniose canina e humana

Abstract

Leishmaniases are neglected infectious diseases that causes serious public health problems. This disease complex can be classified into two main clinic categories: tegumentary leishmaniasis (TL) and visceral leishmaniasis (VL); each one with specific clinical manifestations. In areas where VL is a zoonosis, domestic dogs play an important role as reservoir for the Leishmania parasite, contributing to transmission between the phlebotomine vector and mammals. The diagnosis of VL remains a challenge, either due to the difficulty of clinical differentiation or to the variable sensitivity and specificity of the tests. In this context, the present study, we used bioinformatics to select specific linear B cell epitopes of four Leishmania infantum proteins, which were previously showed to be antigenic for VL, with the aim of producing a new chimeric protein and evaluating it for the diagnosis of canine VL (CVL). Seven B cell epitopes were predicted and used to construct the chimera called “B1”, which was produced and evaluated in a recombinant format by ELISA against a canine serological panel. Results showed that chimera B1 presented excellent sensitivity and specificity values for the diagnosis of CVL. In addition, the study also selected specific B cell epitopes from L. infantum and L. braziliensis proteins for the generation of another chimera called “B2”, with the aim of evaluating it for the diagnosis of human leishmaniasis. ELISA experiments using a human serological panel showed high sensitivity and specificity values for the diagnosis of both TL and VL. In conclusion, preliminary findings suggest that chimeras B1 and B2 have antigenic potential for the diagnosis of canine and human leishmaniasis. Additional studies are needed to evaluate the chimeras under field conditions and in other rapid test diagnostic platforms.