The Delivery Challenge of Genome Editing in Human Epithelia

Exploring Mechanisms of Lipid Nanoparticle-Mucus Interactions in Healthy and Cystic Fibrosis Conditions

Mucus forms the first defense line of human lungs, and as such hampers the efficient delivery of therapeutics to the underlying epithelium. This holds particularly true for genetic cargo such as CRISPR-based gene editing tools which cannot readily surmount the mucosal barrier. While lipid nanoparticles (LNPs) emerge as versatile non-viral gene delivery systems that can help overcome the delivery challenge, many knowledge gaps remain, especially for diseased states such as cystic fibrosis (CF). This study provides fundamental insights into Cas9 mRNA or ribonucleoprotein-loaded LNP-mucus interactions in healthy and diseased states by assessing the impact of the genetic cargo, mucin sialylation, mucin concentration, ionic strength, pH, and polyethylene glycol (PEG) concentration and nature on LNP diffusivity leveraging experimental approaches and Brownian dynamics (BD) simulations. Taken together, this study identifies key mucus and LNP characteristics that are critical to enabling a rational LNP design for transmucosal delivery.

Surface modification of lipid nanoparticles for gene therapy

Gene therapies have the potential to target and effectively treat a variety of diseases including cancer as well as genetic, neurological, and autoimmune disorders. Although we have made significant advances in identifying non-viral strategies to deliver genetic cargo, certain limitations remain. In general, gene delivery is challenging for several reasons including the instabilities of nucleic acids to enzymatic and chemical degradation and the presence of restrictive biological barriers such as cell, endosomal and nuclear membranes. The emergence of lipid nanoparticles (LNPs) helped overcome many of these challenges. Despite its success, further optimization is required for LNPs to yield efficient gene delivery to extrahepatic tissues, as LNPs favor accumulation in the liver after systemic administration. In this mini-review, we provide an overview of current preclinical approaches in that LNP surface modification was leveraged for cell and tissue targeting by conjugating aptamers, antibodies, and peptides among others. In addition to their cell uptake and efficiency-enhancing effects, we outline the (dis-)advantages of the different targeting moieties and commonly used conjugation strategies.

Nanocarriers for Skin Applications: Where Do We Stand?

Skin penetration of active molecules for treatment of diverse diseases is a major field of research owing to the advantages associated with the skin like easy accessibility, reduced systemic‐derived side effects, and increased therapeutic efficacy. Despite these advantages, dermal drug delivery is generally challenging due to the low skin permeability of therapeutics. Although various methods have been developed to improve skin penetration and permeation of therapeutics, they are usually aggressive and could lead to irreversible damage to the stratum corneum. Nanosized carrier systems represent an alternative approach for current technologies, with minimal damage to the natural barrier function of skin. In this Review, the use of nanoparticles to deliver drug molecules, genetic material, and vaccines into the skin is discussed. In addition, nanotoxicology studies and the recent clinical development of nanoparticles are highlighted to shed light on their potential to undergo market translation.