Using siRNA-based spherical nucleic acid nanoparticle conjugates for gene regulation in psoriasis

Area of Science:

• Biotechnology
• Dermatology
• Nanomedicine

Background:

• Psoriasis is a T-cell-mediated autoimmune skin disease lacking adequate animal models.
• Investigating psoriasis pathogenesis is hindered by the absence of suitable experimental models.
• Small interfering RNAs (siRNAs) offer therapeutic potential for gene regulation in skin conditions.

Purpose of the Study:

• To develop and evaluate a safe fusion peptide carrier, spherical nucleic acid gold nanoparticle conjugate (SNA-NCs), for enhanced siRNA delivery in psoriasis.
• To assess the efficacy of EGFR siRNA delivered by SNA-NCs in an imiquimod (IMQ)-induced mouse model of psoriasis.
• To validate the gene suppression and therapeutic effects of SNA-NCs siRNA in vitro and in vivo.

Main Methods:

• An imiquimod (IMQ)-induced mouse model of psoriasis was established.
• Spherical nucleic acid gold nanoparticle conjugates (SNA-NCs) were designed for siRNA delivery.
• Phenotypic, microscopic, and immunohistochemical evaluations were performed on mouse skin.
• Gene expression of EGF and EGFR was monitored using qRT-PCR in human skin cells and mouse models.

Main Results:

• SNA-NCs were found to be stable and non-toxic.
• In vitro studies demonstrated significant reduction in gene expression (EGF & EGFR) using siRNA conjugated with SNA-NCs.
• In vivo experiments showed topical application of siRNA via SNA-NCs significantly inhibited cell proliferation and improved psoriatic-like skin lesions in mice.
• Immunohistochemistry confirmed the inhibitory effect on T-cell markers (CD3, CD4, CD8).

Conclusions:

• Topical application of SNA-NCs siRNA effectively targets and suppresses gene expression in psoriatic skin lesions.
• This novel delivery system demonstrates potential for improving psoriatic-like skin lesions by modulating T-cell activity.
• SNA-NCs represent a promising platform for developing targeted nucleic acid therapies for skin diseases like psoriasis.