Platelet-Rich Plasma associated with solid lipid nanoparticles containing siRNA-TNF-alfa as an innovative approach in the treatment of chronic wounds: production, physicochemical characterization and in vitro efficacy.

• Grant number: 25/15136-2
• Support Opportunities: Scholarships in Brazil - Master
• Start date: November 01, 2025
• End date: March 31, 2027
• Field of knowledge: Health Sciences - Pharmacy - Pharmaceutical Technology
• Principal Investigator: Maria Vitória Lopes Badra Bentley
• Grantee: Lorena Amorim Tiritan
• Host Institution: Faculdade de Ciências Farmacêuticas de Ribeirão Preto (FCFRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated research grant: 14/50928-2 - INCT 2014: Pharmaceutical Nanotechnology: a transdisciplinary approach, AP.TEM

Abstract

Chronic wounds represent a humanitarian and economic challenge for contemporary society. A common characteristic among the different types of chronic wounds is the persistent inflammatory process, which leads to the degradation of growth factors (GFs) and structural proteins in the wound bed, hindering cell proliferation and migration within the wound bed. Tumor necrosis factor alpha (TNF-¿) plays an important role in the persistence of local inflammation, presenting high concentrations in the bed of chronic wounds in humans. Considering the failure of current treatments to provide complete healing of these wounds, this study aims to develop an innovative therapeutic approach using platelet-rich plasma (PRP), a blood component with a high concentration of GFs, combined with TNF-¿ siRNA gene silencing using solid lipid nanoparticles (SLNs), to reduce local inflammation and promote tissue regeneration in chronic wounds. The NLS will be produced using microfluidics and evaluated for their colloidal and physicochemical properties, such as hydrodynamic particle size, polydispersity index, zeta potential, and siRNA complexation efficiency. Stability studies at 4°C and room temperature will be conducted for 90 days. In vitro studies in Franz diffusion cells using dermatomed pig ears will be performed to evaluate siRNA penetration into the skin layers. Throughout the project, PRP bags produced by apheresis machines in partnership with the Ribeirão Preto Blood Center will be cryopreserved, and their viability will be assessed by platelet count, pH analysis, thrombin generation time, PDGF measurement, and platelet viability and activation. Viable PRP samples spiked with NLS siRNA-TNF will have their viscosity adjusted with the addition of hydroxyethylcellulose to ensure the formulation's applicability. Cellular studies will be performed to investigate the formulation's cytocompatibility and cellular uptake. In vitro efficacy studies will be conducted in RAW cell lines, evaluating TNF-alpha gene silencing. A scratch assay in cell culture will be performed to evaluate the pro-healing potential of the formulation produced. The project will result in a multi-target technological and therapeutic feasibility study for the treatment of chronic skin wounds, combining a blood component and NLS-siRNA, an innovative combination of two therapeutic approaches.