Keep the cat, change the care pathway: A transformational approach to managing Fel d 1, the major cat allergen

Abstract

Background Allergies to cats are the most common animal‐origin allergy, and affect approximately 1 in 5 adults worldwide. The prevalence of allergy to furry animals has been increasing, and allergy to cats is a major risk factor for the development of asthma and rhinitis. The diagnosis of cat allergy is now well established. The exact significance of component‐resolved diagnosis in the diagnosis of cat allergy remains to be fully understood. Allergen avoidance is effective but often has a psychologic impact. Allergen immunotherapy is not well demonstrated. There is a need for innovative approaches to better manage cat allergens. Next‐generation care pathways for asthma and rhinitis will define the place of cat allergen avoidance. Methods and Results This manuscript, based on content presented at the European Academy of Allergy and Clinical Immunology Congress 2019, provides information on the prevalence and impact of cat allergies and the molecular biology of Fel d 1, the major cat allergen. Discussion The authors present the scientific basis of a novel care pathway that utilizes anti‐Fel d 1 IgY antibodies to safely and effectively neutralize Fel d 1 after its production by the cat but before human exposure. Conclusion Efficacy of a feline diet with an egg product ingredient containing anti‐Fel d 1 IgY antibodies was demonstrated in vitro, ex vivo, and in vivo, and further validated by a pilot exposure study involving cat‐allergic human participants.

Cat NPC2, a Newly Identified Allergen, With High Cross-Reactivity to Can f 7

“…Pet-derived allergens, in particular cat and dog, affect 7% to 25% of the allergic patients. 28 A deep understanding of cat allergens is crucial for standardizing allergen products for clinical diagnosis and therapy. In this study, we identified and characterized a new cat allergen NPC2 protein, a homolog of dog NPC2 protein which has been identified as Can f 7 allergen by WHO/IUIS and human NPC2 protein.…”

The Major Cat Allergen Fel d 1 Binds Steroid and Fatty Acid Semiochemicals: A Combined In Silico and In Vitro Study

“…Then, elucidating the ligand binding properties of Fel d 1 might provide valuable insights into this putative phenomenon of ligand-induced epitope masking. Along the same line, several approaches aiming at decreasing or controlling the cat production of immunologically active Fel d 1 have recently been investigated in order to alleviate the symptoms suffered by allergic cat owners [69]. In particular, the use of a diet supplemented with anti-Fel d 1 avian IgY [70] or the immunization of cats with a modified form of recombinant Fel d 1 to stimulate the production of neutralizing antibodies [71] have been proposed.…”

Hello, kitty: could cat allergy be a form of intoxication?

“…Administration of monoclonal antibodies that compete with IgE for Fel d 1 were shown to reduce allergy in human patients [ 122 ]. Cat immunization against its own allergen was shown to reduce Fel d 1 levels in the animals [ 123 ], while diet supplementation with anti-Fel d 1 antibodies reduced the protein level in cat saliva [ 124 , 125 ]. In addition to these approaches, at least one biotechnology company is aiming to use CRISPR/Cas9 gene editing to create cats that do not synthesize Fel d 1 in their salivary glands [ 121 ].…”