Development and characterization of an allergoid of cat dander for immunotherapy.
BACKGROUND
Allergy to cats is a frequent cause of sensitization to indoor allergens and currently there are few alternatives to specific immunotherapy with cat native extracts. The objective is to develop and characterize a new allergoid to increase the tools available for use in clinical practice.


METHODS
The allergoid cat dander extract (ACD) was developed from a native cat dander extract (NCD) by modification with glutaraldehyde, and the optimal process control was determined by SDS-PAGE, DOT BLOT and determination of free amine groups. The ACD was characterized in protein profile by SDS-PAGE, size exclusion chromatography (SEC) and peptide footprint. The allergenic profile of ACD was determined by immunoblot, IgE CAP inhibition and IgG competition ELISA. The major allergen content in NCD was obtained by the ELISA sandwich protocol and was extrapolated to ACD.


RESULTS
The control process determined the optimal development of the allergoid. The ACD obtained contains 182.28μg/mg of protein and 11.90μg/mg of Fel d 1. SDS-PAGE and SEC confirmed the presence of high molecular weight proteins in ACD, and the peptide footprint showed the presence of Fel d 1 and Fel d 7. The high degree of polymerization was evidenced with the determination of the reduction of lysine residues in the allergoid, resulting 91.96%. The ACD showed a significant loss of allergenicity respect to NCD, while the IgG-binding capacity was maintained.


CONCLUSIONS
The ACD obtained presents a good safety profile, so would be a good alternative for treatment of cat allergy.
['Sola|J P|JP|', 'Pedreño|Y|Y|', 'Cerezo|A|A|', 'Peñalver-Mellado|M|M|']
D000485:Allergens D000818:Animals D002415:Cats D063607:Dander D003888:Desensitization, Immunologic D006801:Humans D006967:Hypersensitivity
Allergoid Cat dander Immunotherapy Safety Allergen-specific IgE