Análise preliminar de antígeno recombinante e peptídeos sintéticos aplicados no diagnóstico da leishmaniose tegumentar utilizando urina dos pacientes

Abstract

Leishmaniasis are endemic diseases that affect approximately one billion people in over 90 countries worldwide. Tegumentary leishmaniasis (TL) is the most common form and exhibits wide clinical variability, significantly impacting the health and quality of life of patients. Early diagnosis is essential for effective treatment and prevention of severe cases. However, conventional parasitological or molecular diagnosis involves invasive collection of biological samples, has variable sensitivity, and/or is costly. Enzyme-linked immunosorbent assays (ELISA) are alternatives, although issues related to test sensitivity and the need for invasive blood collection exist. In this regard, the identification of new antigens for improving TL diagnosis would be attractive, as well as the use of non-invasively collected biological samples. In this study, the eukaryotic initiation factor 5a (eIF5A) protein, previously identified by immunoproteomics in Leishmania braziliensis, along with its B-cell-specific epitope predicted by bioinformatics, were tested for TL diagnosis using patient urine compared to serum. Indirect was performed with the recombinant protein, its peptide, and the soluble antigenic extract of parasites (SLA). The use of urine showed better sensitivity and specificity values compared to serum, with sensitivity values of 100%, 76.2%, and 95.56%, and specificity of 100%, 86.7%, and 100% for the reIF5A protein, synthetic peptide, and SLA, respectively. In contrast, the use of serum demonstrated sensitivity values of 79.07%, 76.19%, and 77.27%, and specificity of 100%, 88.89%, and 95.35% for the protein, peptide, and SLA, respectively. The recombinant protein showed better values compared to other antigens, and the urine-based ELISA had slightly higher values than serum usage. Thus, this study provides preliminary data on the possibility of using reIF5A protein and urine for the diagnosis of LT.