## 4 Nanostructured Systems for Immunotherapeutic Delivery in Non- Malignant Applications
### Allergic and Inflammatory Disorders
Encouraging results were obtained, with the nanoformulation effectively shifting the immune response from a Th2-dominated profile, which is associated with allergies, towards a Th1 response, characterized by reduced allergic inflammation and the enhanced production of IFN-\(\gamma\). These outcomes highlight the promise these delivery systems hold for mitigating allergic diseases by modulating the immune response. [PERSON] et al. [147] also reported an interesting study in this domain. The authors fabricated and tested poly(anhydride) nanoparticles loaded with cashew nut allergens as a strategy for cashew nut oral immunization. The study results reveal that the developed nanoformulation promotes a strong Th1-mediated and Treg immune response, highlighting its potential as a candidate for the oral delivery of allergens to modulate immune responses in food allergy treatments. Differently, [PERSON] et al. [148] developed DermAll, a nanomedicine designed for allergen-specific immunotherapy based on a synthetic plasmid pDNA/PEIm and ovalbumin as a model allergen. The proposed approach effectively modulated the immune response by promoting a shift towards a Th1-type response and inducing regulatory T cells, thereby reducing the Th2-mediated allergic response. These findings suggest that DermAll offers a promising alternative for allergen-specific immunotherapy, with potential benefits in terms of both efficacy and patient compliance. [PERSON] et al. [149] focused their research on cat allergic rhinitis, testing the efficacy of an intranasal liposome-adjuvant vaccine containing refined Fel d 1 on a mouse model. The obtained results demonstrate that the vaccine effectively reduces allergic symptoms and airway inflammation in sensitized mice by inducing a shift from a Th2-dominated response towards a Th1 and regulatory T-cell response. This suggests that the intranasal liposome-adjuvant Fel d 1 vaccine could be a promising therapeutic approach for managing cat allergy, offering potential advantages in targeting local immune responses in the nasal mucosa. [PERSON] et al. [150] also addressed the benefits of using liposomes for delivering allergens. Specifically, the researchers evaluated neutral and cationic liposomes as delivery systems of ovalbumin for allergy treatment by sublingual immunotherapy (SLIT). The study confirms that encapsulating allergens within liposomes improves their stability and bioavailability, leading to a more robust immune response characterized by a shift towards a Th1/Th2 balance and the increased production of Tregs, offering a promising approach for more effective SLIT. Overall, several interesting and encouraging results have been obtained concerning the nanomaterial-mediated immunotherapy of allergies and inflammatory diseases. However, most identified studies are over a decade old, and little progress has been registered since their publication. Hence, research in this field seems to have been stalled, requiring further advancements from interconnected disciplines before bringing new perspectives to clinical practice.