[In silico analysis of the identity of lipocalin of dog, cat, horse, cow, hamster and hen. Possible role in allergic diseases].

BACKGROUND

Lipocalins seem to explain the cross-reactivity between some pets such as cat and dog. However, its role in other animals and its possible clinical impact in allergy diseases have been scarcely studied.

OBJECTIVE

To analyze by bioinformatics techniques, the identity between lipocalin of some animals and to explore the clinical impact on allergic diseases.

MATERIAL AND METHOD

An in silico study was done to search for lipocalin sequences using the BLAST program of NCBI Database. The protein sequences were aligned with CLUSTAL Omega UniProt version 1.2.1 software. The base sequences for alignments were lipocalins dogs and cats. The defined percentage identity was compared with the frequency of sensitization to animals exposed in a population of 284 patients with suspected allergic diseases.

RESULTS

Identities between sequences were 10% to 70%. The highest values were found with Can f 6-Fel d 4 (68%) and Fel d 4-Equ c 1 (68%). The lower identity was found with lipocalin porpurin and retinol binding (<20%). We observed a relationship between sensitization and the percent identity between the species studied.

CONCLUSION

Lipocalins as Can f 6, Fel de 4 and Equ c 1 seem to play an important role in the cross-reactivity to cat, horse and dog but not for the co-sensitization to hamster, cow or birds. Fel de 4 and Equ c 1 could be a prevalent allergen for horse and cat. These results come from predictive analysis and must be confirmed by in vitro and in vivo studies.