Allergenicity and cross‐reactivity of cat and dog allergenic extracts

Abstract

This study aims to eonfirm that eat allergen I (CAT-1) is a major allergenic determinant in cat-sensitive patients, and to further define the role of other determinants, as well as to identify the determinants responsible for the cross-reactivity between cat and dog extracts. Firstly, the allergenic determinant with an electrophoretic mobility of 18 kD (corresponding to CAT-1) is indeed a major allergenic determinant being recognized by the majority (75%) of cat-sensitive subjects. Secondly, the cross-reactivity between the two species was confirmed by RAST inhibition. Cat and dog soluble allergens could inhibit, to variable degrees, the binding of serum IgE from cat-and dog-sensitive patients to insolubilized allergens. Binding of serum IgE from subjects sensitive only to cats was inhibited by cat extracts only. These observations suggest the presence of determinants common to the two sources of extracts, and others specific for each species. These data were confirmed by immunoblot analysis. Indeed, an allergenic determinant of 69 kD was found in both cat and dog extracts. Conversely the allergenic determinants with an electrophoretic mobility of 18 and 32 kD were found only in cat extracts, and those at 22 and 24 kD were dog specific. However, surprisingly, serum IgE antibodies from patients sensitive only to cats reacted on immunoblot differently from those of both cat-and dog-allergic subjects. Indeed, the 18 kD determinant was the only one recognized by serum IgE antibodies from subjects sensitive to cats only, as opposed to the patients allergic to both species: then, the 69 kD determinant was strongly recognized and the 18 kD only slightly recognized. If these observations confirmed that CAT-1 is a major allergen in

From allergen sources to reduction of allergen exposure

“…Can f I is a polypeptide with a molecular weight of 22-25 kD. Albumin is another allergen of some importance, the molecule is considered responsible for cross reaction between cat and dog extracts [24]. Assays based on monoclonal or monospecific antibodies have shown Can f I levels to be one order of magnitude above those of Fel d I i.e.…”

Allergic Rhinitis and its Impact on Asthma (ARIA) 2008*

“…Patients allergic to cats and dogs frequently display IgE reactivity against allergens from different animals (444,445). Albumins have been recognized as relevant crossreactive allergens (446).…”

The Principle of Homologous Groups in Regulatory Affairs of Allergen Products – A Proposal

“…Only one allergen, the 69-kDa albumin, is present in both species and is known as a cross-reactive allergen (table 12) [118]. Nevertheless, inhibition studies surprisingly showed cross-reactivity of cat and dog extracts under certain conditions [108,118,119,120]. Data demonstrated cross-reactivity for cat hair and dog hair but not for cat saliva and dog saliva or cat urine and dog urine, respectively [108].…”