Abstract:
Psoriasis is a chronic, incurable inflammatory skin disease characterized by immune cell infiltration, aberrant keratinocyte differentiation, and enhanced angiogenesis. Overexpression of the vascular endothelial growth factor-A (VEGF-A) gene promotes angiogenesis and is essential for endothelial cell migration, adhesion, and proliferation. Therefore, downregulating VEGF-A represents a promising therapeutic strategy for angiogenesis-related disorders. We investigated the application of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) ribonucleoprotein complexes (sgRNA/eGFP-Cas9 RNPs) targeting VEGF-A in psoriasis. To enable efficient delivery in vitro and in vivo, we developed lipopolymeric nanoplexes (NPXs) encapsulating sgRNA/eGFP-Cas9 RNPs. These NPXs exhibited a particle size of 142.2 nm (polydispersity index: 0.144), a zeta potential of +4.27 mV, and achieved >70% transfection efficiency in HaCaT (human immortalized keratinocyte) cells. Ex vivo skin permeation studies demonstrated 66% of permeation after 24 h. The optimized NPX formulation was incorporated into a Carbopol-based gel, which displayed non-Newtonian, shear-thinning behavior with variable thixotropy and achieved 48% of skin permeation after 24 h. In vivo efficacy assessment in an imiquimod-induced psoriasis model in Swiss albino mice showed significantly improved Psoriasis Area and Severity Index (PASI) scores, reduced epidermal damage, and suppressed keratinocyte proliferation compared to naked RNPs and blank gel controls. Gene editing analysis revealed an indel frequency of 40.7% by T7 endonuclease I assay and 14% by Sanger sequencing. Enhanced cellular uptake, efficient skin permeation and retention, and improved therapeutic efficacy collectively highlight the potential of NPX-mediated CRISPR/Cas9 delivery as a noninvasive strategy for psoriasis treatment.