D1.349 - Age-related fungal molecular clusters revealed by allergen chip assay in Eastern France

Exposure to airborne fungi is ubiquitous. Fungal sensitization (FS) is associated with adverse health effects such as lung function deterioration in asthmatic patients. It is increasingly understood that FS often occurs as clusters of cross-reactivity among shared molecular families. We sought to describe the molecular patterns of FS as a function of age in subjects living in the Champagne region in Eastern France and to compare with results previously obtained in Southern France.

Retrospective analysis of FS in patients undergoing allergen chip investigation (ImmunoCAP ISAC® 112, Thermo Fisher Scientific, Sweden) for allergy diagnosis, 2020-2022. Deidentified data were collected within the framework of the nationwide Allergen Chip Challenge project conducted by the French Society of Allergology. IgE to Alt a 1, Alt a 6, Asp f 1, Asp f 3, Asp f 6 and Cla h 8 were analyzed.

Data were collected for 192 consecutive patients from Reims, Eastern France, median age 10 years (0-78), sex ratio 1.52. Alt a 1 IgE was the most prevalent (26%), followed by Alt a 6, Asp f 3, Asp f 6 equally (3%), Asp f 1 and Cla h 8 (1-2% each). FS to marker allergens varied as a function of age: Alt a 1 and Cla h 8 prevailed in the pediatric group (0-17 years) at 28% and 2% respectively. Asp f 1 was found only in adults (4.2%, 18-40 years), at a prevalence lower than its cross-reactive counterparts Asp f 3 and Asp f 6 (up to 13% in adults). 

A. alternata was the most frequent genuine sensitizer in this sample of Eastern French population. Interestingly, genuine sensitization to A. fumigatus (Asp f 1) was unfrequent, contrasting to sustained prevalence of FS to cross-reactive allergens. Given the widespread champagne vine-growing occupational and environmental exposure of our population, we speculate that fungal species associated with vineyards and wine-making may be involved. Compared with our previous study on Southern French patients, overall FS trend was higher in Reims (32% vs 26%). Despite increased awareness of the health impact of fungal exposome, investigation of FS in allergic patients is still hampered by a lack of clinical and molecular tools to identify primary sensitizers, cross-reactive patterns and clinical implications.