In silico analysis of molecular mimicry between Der p 23 and allergenic sources

Abstract

Objective: To identify, through in silico analysis, the potential molecular mimicry between Der p 23 and antigens from allergenic sources.

Methods: Identity between Der p 23 and proteins from the families Pyroglyphidae, Acaridae, Chortoglyphidae, and Echimyopodidae was searched using PSI-BLAST, and alignments were performed using PRALINE and EMBOSS. Antigens with resolved experimental structures were obtained from the Protein Data Bank, while those not reported were generated using Swiss Model Server and ALPHAFOLD 2. Epitope prediction was conducted with the Ellipro server, and 3D model visualization was performed using Pymol 2.3.

Results: The analysis between Pyroglyphidae allergens and Der p 23 showed identity with an endochitinase-like protein from D. pteronyssinus and a type 2 chitin-binding domain from D. farinae, with identities ranging from 85% to 100% and coverages of 100% and 75%, respectively. The allergens Der f 23 and Der p 23 from D. farinae and D. pteronyssinus showed 100% coverage, with identities of 85.42% and 79.59%, respectively. Among Tyrophagus putrescentiae allergens, chitin-binding protein, oviduct-specific glycoprotein, and Cda4p showed identity values of 40%, 42.22%, and 34.78%, with coverage values not exceeding 55%. No results were found for Chortoglyphidae and Echimyopodidae.

Conclusion: Molecular mimicry and structural homology exist between Der p 23 and allergens from the Pyroglyphidae and Acaridae families. Potential epitopes in Der p 23 were identified, which could present cross-reactivity with proteins from the allergenic sources studied, which should be confirmed through in vitro and in vivo studies. Further in vitro and in vivo research is needed to validate the findings from the in silico analysis.