Associations of Protein Classes With Cross-Reactivity and Cross-Sensitization in Furry Animal Allergens: A Component-Resolved Diagnostics Study

Jiancai Lu,1,&ast; Huiqing Zhu,2,&ast; Qingqing Yang,1 Yunjian Xu,1 Zhifeng Huang,1 Baoqing Sun1 1Department of Clinical Laboratory, National Center for Respiratory Medicine, National Clinical Research Center for Respiratory Disease, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510120, People’s Republic of China; 2Department of Clinical Laboratory, Huizhou Central People`s Hospital, Huizhou, Guangdong, 516001, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Baoqing Sun; Zhifeng Huang, Department of Clinical Laboratory, National Center for Respiratory Medicine, National Clinical Research Center for Respiratory Disease, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, the First Affiliated Hospital of Guangzhou Medical University, 151 Yanjiang Road, Guangzhou, Guangdong, 510120, People’s Republic of China, Tel +86 020 81568020, Email [email protected]; [email protected]: This study aimed to investigate the molecular sensitization patterns of cats, dogs, and horses in patients with cat and/or dog sensitization and the IgE cross-reactivity with other furry animals.Methods: In 95 patients diagnosed with allergic diseases and sensitized to cats and/or dogs (confirmed by specific Immunoglobulin E (sIgE) ≥ 0.35 kUA/L to crude cat and/or dog dander extracts), sIgE levels of cat components (Fel d 1/2/4), dog components (Can f 1/2/3/5), horse dander (Equ c 1), as well as allergens from cow, guinea pig, mouse, rat, rabbit, and chicken, were measured. Sensitization profiles and cross-reactivity were analyzed. Inhibition tests using serum albumin (SA) and lipocalin proteins were performed.Results: Sensitization rates of crude extracts from other furry animals ranged from 16.8% to 49.5%. A strong positive correlation between cat and dog serum albumin (Fel d 2 and Can f 3) and rabbit epithelium, mouse epithelium, guinea pig epithelium and rat epithelium (rs: 0.66– 0.87, all P < 0.05), while the lipocalin family (Fel d 4, Can f 1, Can f 2 and Equ c 1) only had a low to moderate correlation with the epithelial allergens of the above four animals (rs: 0.36– 0.65, all P < 0.05). Simultaneous sensitization to SA and these four furry animal allergens accounted for 42.4%. sIgE levels of furry animal extracts were significantly higher in SA-positive groups (all P < 0.05) The results of the inhibition test showed that Fel d 2 and Can f 3 had high inhibition rates of four epithelial allergens, ranging from 66.5% to 91.8% and 75.8% to 91.9%, respectively. When lipocalin family components were used as inhibitors, the sIgE inhibition rates of these furry animal extracts were almost all lower than 50%.Conclusion: SA is the primary driver of cross-sensitization between cats, dogs, and other furry animals, rather than lipocalins.Keywords: animal allergen, sIgE, component-resolved diagnosis, CRD, serum albumin, cross-reactivity