Abstract / Summary
Abstract Asthma continues to pose a major clinical burden despite the availability of modern biologic therapies. In eosinophilic asthma, the transcription factor GATA3 is a key regulator of Th 2 differentiation and type 2 cytokine production and therefore represents an attractive target for siRNA-based intervention. We previously established a transferrin-functionalized polyethyleneimine (Tf-PEI) polyplex system for targeted siRNA delivery to human T-cells. Here, we aimed to translate and adapt this platform to the murine system to enable therapeutic evaluation in a preclinical asthma model. Accordingly, a murine Tf-PEI polyplex system was developed for targeted delivery of siRNA to activated T-cells in the lung. Murine CD4⁺ T-cells were polarized toward a Th 2 phenotype and used to assess nanoparticle uptake and functional GATA3 silencing in vitro . The performance of the polyplexes was further evaluated in activated murine precision-cut lung slices and in an ovalbumin-induced murine asthma model. While non-targeted PEI showed high cellular uptake, this did not translate into efficient or sequence-specific gene silencing. In contrast, Tf-functionalized polyplexes enabled functional GATA3 knockdown, with partially functionalized Tf-PEI outperforming fully functionalized formulations. The optimized 50% Tf-PEI blend achieved the strongest silencing in primary Th 2 cells and lung slices and mediated an approximate 50% reduction in GATA3 mRNA levels in vivo . In the murine asthma model, this was accompanied by reduced inflammatory cell infiltration, improved lung histopathology, and the lack of pronounced inflammatory responses under the tested conditions. Collectively, our results demonstrate that precise tuning of transferrin ligand density critically controls functional siRNA delivery to pulmonary T-cells in vivo , establishing a rational design framework for targeted RNA nanotherapeutics against type 2 airway inflammation.