Swiss researchers have developed an experimental cell therapy for allergic asthma linked to birch pollen allergy. In a preclinical study, the technology reduced allergic inflammation and improved lung function in animals. The findings were published in the Journal of Experimental Medicine.
The technology is based on modified regulatory T‑cells, into which a chimeric allergen receptor called CAlleR has been inserted – modelled on chimeric antigen receptors. The receptor enables the cells to recognise Bet v1, the main birch pollen allergen, and suppress allergic inflammation.
The researchers identified four new monoclonal antibodies against Bet v1 and used them to construct the chimeric allergen receptors. The modified T‑cells were activated only when exposed to the target allergen, retained their immunoregulatory properties, and migrated to the lungs and mediastinal lymph nodes, where they interacted with dendritic cells.
Unlike conventional allergen‑specific immunotherapy, which has limitations and is contraindicated in patients with severe uncontrolled asthma, CAlleR‑Treg cells are designed to restore immune tolerance to a specific allergen. This approach could potentially expand treatment options for severe allergic diseases where existing therapies remain insufficiently effective.
The researchers stressed that the study is preclinical and was conducted only in animal models. Clinical trials will be needed to assess the safety and efficacy of the new technology. Nevertheless, the authors believe the results open up prospects for developing personalised cell‑based therapies for severe allergic asthma and other allergen‑associated diseases.
In Russia, a birch pollen allergy vaccine called Allergarda is also under development and could become the first in its class worldwide. The vaccine is being developed by the Institute of Immunology of the Federal Medical‑Biological Agency. The agency’s head said earlier that registration is expected in 2026, with the drug planned to enter civilian circulation in 2027. Clinical trials showed that 25% of patients experienced no allergy symptoms at all, while the majority tolerated the pollen season more easily.