Mapping Mimotopes for House Dust Mite Allergen Der f 7 Using a Specific Monoclonal Antibody.

BACKGROUND: The dust mite Dermatophagoides farinae is a common worldwide cause of indoor allergies induced by mite proteins, including the mid-tier allergen Der f 7. Objective To identify conformational epitopes in Der f 7 using mimotope mapping and computational modelling.

METHODS: Here, we used standard hybridoma technology to generate 3 new monoclonal antibodies against Der f 7 and performed mimotope mapping by probing a random peptide phage display library. Computational tools, including Minox and the DiscoTope-2.0 Server were used to assess the structure and potential position of antigenic residues within Der f 7.

RESULTS: Thirteen mimotopes sharing the common sequence --XX[LST]P[-E][LI]MLPLR[-S]- were identified. Further, computationally-predicted conformational epitopes were found at residues 1-7, 10, 27, 76-81, 92, and 130-133 of Der f 7, and the key amino acids for these epitopes were deduced to be 2P, 3I, 10E, 27E, 78E, 79E, 81I, 130S, and 132E based on the common mimotope sequence. Conclusion We identified Der f 7 peptide mimotopes that may model binding sites for blocking antibodies. These may guide the development of immunotherapy for individuals with hypersensitivity to Der f 7.