In silico identification of immunogenic proteins of Angiostrongylus costaricensis with potential diagnostic relevance.

Angiostrongylus costaricensis is a zoonotic parasite that causes abdominal angiostrongyliasis. This disease poses a significant diagnostic challenge, mainly because of the limited availability of methods with adequate specificity and sensitivity. To contribute to the development of more accurate diagnostic tools, this study employed an in silico approach to identify species-specific proteins with immunogenic potential. A set of 176 proteins previously described as specific to A. costaricensis was used as a starting point. Their subcellular localization was predicted using DeepLoc 2.1, prioritizing proteins predicted to be secreted or extracellularly localized. In parallel, the most frequent HLA-DRβ alleles in endemic regions were identified through analysis of population databases. Based on this selection, MHC class II-binding epitopes were predicted using NetMHCIIpan 4.3, and conformational B-cell epitopes were predicted using DiscoTope 3.0. As a result, nine candidate proteins were prioritized based on extracellular localization and the presence of ≥10 strong MHC II-binding peptides. Conformational B-cell epitope analysis identified antigenic regions in seven of these proteins. In addition, sequence similarity with proteins from other clinically relevant helminths was assessed to evaluate the potential risk of cross-reactivity. Taken together, these findings identify promising candidates for the development of more sensitive and specific diagnostic tools for abdominal angiostrongyliasis, with potential to improve timely diagnosis and clinical management of this parasitosis.