IN SILICO ANALYSIS OF MOLECULAR MIMICRY BETWEEN HUMAN AQUAPORIN 3,
Aspergillus fumigatus AQUAPORIN AND AQUAPORINS FROM ALLERGIC SOURCES.
Background: Atopic dermatitis (AD) is a chronic skin condition
impacting quality of life. Allergen recognition via specific IgE
triggers immune responses and allergy symptoms. Cross-reactivity may
induce auto-IgE responses and worsen AD. We aimed to analyze molecular
mimicry between human AQP3 and Aspergillus fumigatus aquaporin, a
potential allergen source. Methods: In silico analysis compared
human (AQP3) and A. fumigatus aquaporin sequences with 25 aquaporins
from allergenic sources. Sequences were obtained from UniProt and NCBI.
Phylogenetic relationships and homology-based modeling were performed,
with ElliPro predicting conserved antigenic regions on 3D structures.
Results: Global identity among aquaporins was 32.6%, but one
antigenic site exhibited 71.4% local conservation. Five monophyletic
clades (A to E) were formed. Group B showed the highest identity (95%),
including 6 mammalian aquaporins, including AQP3. A. fumigatus aquaporin
shared the highest identity with Malassezia sympodialis (35%). Both
human and A. fumigatus aquaporins featured three linear and three
discontinuous epitopes, with a root mean square deviation (RMSD) of
1.006. Conclusion: Possible linear and conformational epitopes
on AQP3 were identified. High identity in one antigenic region suggests
molecular mimicry between human and A. fumigatus aquaporins, potentially
leading to autoreactivity and cross-reactivity. Further in vitro and in
vivo studies are needed to confirm these findings.