Title : Subtractive proteomics and immunoinformatics based design of a chimeric antigen for Leishmania aethiopica to diagnose cutaneous leishmaniasis
Abstract:
Leishmania aethiopica is a protozoan parasite that is the main causative agent of cutaneous leishmaniasis (CL), a debilitating skin disease in Ethiopia. Currently, there are no L. aethiopica targeting immunodiagnostics on the market. This study identified candidate proteins of L. aethiopica using subtractive proteomics and immunoinformatics approaches. About 8,000 proteomes were carefully filtered using a stepwise methodology that employs strict criteria to identify proteins that are parasite survival specific and non-homologous to human and human gut proteins. These candidate proteins were further investigated to predict B-cell epitopes and were prioritized based on antigenicity scores. The lead epitopes were linked together by linker sequences in between the epitopes and also with tags on both the N- and C- terminus resulting in a multi-epitope construct. The construct’s physicochemical properties were characterized. The secondary structure model of the designed construct was predicted and its features were analyzed. The construct was optimized for its codon and cloned in silico in Escherichia coli expression system. The findings indicated that the antigen construct is immunogenic, soluble and stable. The in silico prediction studies are crucial for the development of a diagnostic tool for CL. The efficacy of this novel biomarker should be confirmed with in vitro studies and subsequent clinical investigations.
Keywords: Leishmania aethiopica, cutaneous leishmaniasis, subtractive proteomics, immunoinformatics, multiepitope antigen, diagnostic development.
