Cyclodextrin-Based Nanosponges as a Nanotechnology Strategy for Imiquimod Delivery in Pathological Scarring Prevention and Treatment

Although hypertrophic scars are a common complication in a high percentage of burn injuries, to date their optimal treatment still remains to be established. Herein, the antiproliferative effect of Imiquimod on human fibroblasts is evaluated and an innovative nanotechnological approach for Imiquimod delivery by pyromellitic βcyclodextrin-based nanosponges is proposed. We observed that Imiquimod inhibits cell proliferation and induces apoptosis of normal skin and hypertrophic scar fibroblasts. When incorporated into βcyclodextrin-based nanosponges, Imiquimod shows a high encapsulation efficiency and a slow and prolonged in vitro kinetic release. These features give Imiquimod-loaded nanosponges a greater antiproliferative effect on human fibroblasts and on an immortalized non-tumorigenic keratinocyte cell line, compared to free Imiquimod. In conclusion, we suggest that this innovative nanomedicine formulation could provide an important contribution to the prevention and therapy of post-burn hypertrophic scars by combining the antiproliferative capacity of Imiquimod with the ability of the nanosponges to enhance the drug activity.