From Prevention to Actual Therapy: A New Chapter in Asthma Research
For decades, the “farm effect” has fascinated scientists: children raised on farms consistently show lower rates of asthma. Yet most studies have focused solely on how farm environments prevent allergic disease. This new work goes a step further—opening the door to therapeutic intervention.
Remarkably, even under these therapeutic conditions, the intransal application of a farm dust extract (FDE) significantly reversed core features of allergic asthma, including airway eosinophilia, mucus hypersecretion, airway hyperresponsiveness (AHR), and IgE levels.
Together, these findings demonstrate that the principles of environmental immune training can be harnessed not only to prevent asthma, but to actively treat established disease—even after the allergic cascade is already in motion.
Strong Impact on Inflammation, Barrier Function and Immune Rebalancing
The therapeutic effects of the farm dust extract were astonishing: mice treated with FDE showed a powerful reduction in airway inflammation and bronchial hyperresponsiveness—reaching efficacy levels comparable to systemic dexamethasone, one of the most potent anti-inflammatory drugs used in asthma therapy—marking a major conceptual leap forward by demonstrating that a natural environmental extract can deliver clinically meaningful improvement. At the same time, FDE drove a profound shift toward immune regulation, elevating both the frequency and activation state of regulatory T cells (as reflected by increased CTLA-4), reshaping dendritic cells toward a tolerogenic phenotype through altered MHC-II and PD-L1 expression, restoring epithelial barrier integrity, and enhancing IL-33 release to reinforce epithelial–immune communication. Importantly, these effects extended to human disease biology, as PBMCs from asthma patients showed the same immunomodulatory signature. This highlights that FDE does not merely suppress inflammation but fundamentally rewires the allergic immune system across species, offering a powerful blueprint for future therapies in human asthma.
Toward a New Type of Asthma Therapy
“Our data reveal that farm-dust derived extracts, when given after allergen sensitization, can mitigate key features of allergic airway inflammation,” notes first author Dr Rabia Ü. Korkmaz. “Instead of merely suppressing symptoms, this approach targets the underlying dialogue between the immune system and the airway epithelium. By restoring this balance, we open the door to a new class of environmentally inspired asthma therapies that strengthen airway resilience and promote long-term immune regulation.”
Next Steps & Clinical Translation
Further work will be needed to clarify safety, dosing, and efficacy in humans. Clinical trials will be required to test whether farm-dust derived compounds can be developed into inhalation treatments or adjunctive therapies. If successful, the strategy could complement current treatments and shift asthma care from symptom management toward immune-modulating restoration.
Original publication
Korkmaz RÜ et al. (2025) The therapeutic potential of farm dust extracts in a mouse model of eosinophilic inflammation. Allergy. DOI: 10.1111/all.70121.
The key findings of the paper are presented by the first author on Allergy's YouTube channel.
About the scientists
Prof. Dr. med. Dr. h.c. Erika von Mutius, Director of the Institute of Asthma & Allergy Prevention at Helmholtz Munich and co-lead of the study
Dr. Rabia Ülkü Korkmaz, first author and scientist at the Institute of Asthma & Allergy Prevention, Helmholtz Munich
About IAP
The Institute of Asthma & Allergy Prevention (IAP) at Helmholtz Munich conducts translational research from environmental exposures to novel therapies—with the aim of shifting the paradigm in allergy and respiratory disease prevention and treatment.