Development and characterization of an allergoid of cat dander for immunotherapy
Main Article Content
Keywords
Allergen-specific IgE, Allergoid, Cat dander, Immunotherapy, Safety
Abstract
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 182.28 g/mg of protein and 11.90 g/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.
References
2. Zahradnik E, Raulf M. Animal allergens and their presence in the environment; 2014.
3. Bousquet P, Chinn S, Janson C, Kogevinas M, Burney P, Jarvis D. European Community Respiratory Health Survey I Geographical variation in the prevalence of positive skin tests to environmental aeroallergens in the European Community Respiratory Health Survey I. Allergy. 2007;62:301-9.
4. Heinrich J, Bedada GB, Zock J, Chinn S, Norbäck D, Olivieri M, et al. Cat allergen level: its determinants and relationship to specific IgE to cat across European centers. J Allergy Clin Immunol. 2006;118:674-81.
5. Arbes SJ, Gergen PJ, Elliott L, Zeldin DC. Prevalences of positive skin test responses to 10 common allergens in the US population: results from the third National Health and Nutrition Examination Survey. J Allergy Clin Immunol. 2005;116: 377-83.
6. Bousquet J, Lockey R, Malling H, Alvarez-Cuesta E, Canonica G, Chapman M, et al. Allergen immunotherapy: therapeutic vaccines for allergic diseases. Ann Allergy Asthma Immunol. 1998;81:401-5.
7. Almqvist C, Wickman M, Perfetti L, Berglind N, Renstrom A, HedrÉn M, et al. Worsening of asthma in children allergic to cats, after indirect exposure to cat at school. Am J Respir Crit Care Med. 2001;163:694-8.
8. Ritz B, Hoelscher B, Frye C, Meyer I, Heinrich J. Allergic sensitization owing to ‘second-hand’ cat exposure in schools. Allergy. 2002;57:357-61.
9. Grammer LC, Shaughnessy MA, Patterson R. Modified forms of allergen immunotherapy. J Allergy Clin Immunol. 1985;76:397-401.
10. Casanovas M, Fernandez-Caldas E, Alamar R, Basomba A. Comparative study of tolerance between unmodified and high doses of chemically modified allergen vaccines of Dermatophagoides pteronyssinus. Int Arch Allergy Immunol. 2005;137: 211-8.
11. Yang X, Gieni RS, Mosmann TR, HayGlass KT. Chemically modified antigen preferentially elicits induction of Th1-like cytokine synthesis patterns in vivo. J Exp Med. 1993;178:349-53.
12. Akdis C, Blaser K. Mechanisms of allergen-specific immunotherapy. Allergy. 2000;55:522-30.
13. Morales M, Gallego M, Iraola V, Taulés M, de Oliveira E, Moya R, et al. In vitro evidence of efficacy and safety of a polymerized cat dander extract for allergen immunotherapy. BMC Immunol. 2017;18:10.
14. Committee for Medicinal Products for Human Use. Guideline on allergen products: production and quality issues. European Medicines Agency; 2008.
15. European Directorate for the Quality of Medicines (EDQM). Monograph: Allergen Products --- Producta Allergenica 01/2010: 1063; 2010.
16. Brake B. Specifications: Test Procedures and Acceptance Criteria for Biotechnological/Biological Products; 2011.
17. Overell BG. Modified allergens: criteria for standardisation. Arb Paul Ehrlich Inst Bundesamt Sera Impfstoffe Frankf A M. 1988;82:233-41.
18. Methods of Analysis. Council of Europe (COE) - European Directorate for the Quality of Medicines; 2004. p. 138-41.
19. Silva C, Sousa F, Gubitz G, Cavaco-Paulo A. Chemical modifications on proteins using glutaraldehyde. Food Technol Biotechnol. 2004;42:51-6.
20. Pharmacopeia U. USP 29. Rockville, MD: US Pharmacopeial Convention Inc.; 2006.
21. Schäfer T, Stieger B, Polzius R, Krauspe A. Associations between cat keeping, allergen exposure, allergic sensitization and atopic diseases: results from the Children of Lübeck Allergy and Environment Study (KLAUS). Pediatr Allergy Immunol. 2009;20:353-7.
22. Hedlin G, Heilborn H, Lilja G, Norrlind K, Pegelow K, Schou C, et al. Long-term follow-up of patients treated with a three-year course of cat or dog immunotherapy. J Allergy Clin Immunol. 1995;96:879-85.
23. Nanda A, O’connor M, Anand M, Dreskin SC, Zhang L, Hines B, et al. Dose dependence and time course of the immunologic response to administration of standardized cat allergen extract. J Allergy Clin Immunol. 2004;114:1339-44.
24. Demoly P, Calderon MA. Dosing and efficacy in specific immunotherapy. Allergy. 2011;66(s95):38-40.
25. Counsell CM, Bond JF, Ohman JL, Greenstein JL, Garman RD. Definition of the human T-cell epitopes of Fel d 1, the major allergen of the domestic cat. J Allergy Clin Immunol. 1996;98:884-94.
26. De Groot AS, Scott DW. Immunogenicity of protein therapeutics. Trends Immunol. 2007;28:482-90.