Recombinant filaggrin is internalized and processed to correct filaggrin deficiency.

Abstract

This study was designed to engineer a functional filaggrin (FLG) monomer linked to a cell-penetrating peptide (RMR) and to test the ability of this peptide to penetrate epidermal tissue as a therapeutic strategy for genetically determined atopic dermatitis (AD). A single repeat of the murine filaggrin gene (Flg) was covalently linked to a RMR motif and cloned into a bacterial expression system for protein production. Purified FLG+RMR (mFLG+RMR) was applied in vitro to HEK-293T cells and a reconstructed human epidermis (RHE) tissue model. Immunochemistry demonstrated RMR-dependent cellular uptake of FLG+RMR in a dose- and time-dependent manner in HEK cells. Immunohistochemical staining of the RHE model identified penetration of FLG+RMR to the stratum granulosum, the epidermal layer at which FLG deficiency is thought to be pathologically relevant. In vivo application of FLG+RMR to FLG-deficient flaky tail (ft/ft) mice skin demonstrated internalization and processing of recombinant FLG+RMR to restore the normal phenotype. These results suggest that topically applied RMR-linked FLG monomers are able to penetrate epidermal tissue, be internalized into the appropriate cell type, and be processed to a size similar to wild-type functional barrier peptides to restore necessary barrier function, and prove to be therapeutic for patients with AD.

• Authors: Thomas E Stout, Trevor McFarland, John C Mitchell, Binoy Appukuttan, J Timothy Stout
• Journal: The Journal of investigative dermatology (J Invest Dermatol) Vol. 134 Issue 2 Pg. 423-429 (Feb 2014) ISSN: 1523-1747 [Electronic] United States
• PMID: 23792461 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• FLG protein, human
• Filaggrin Proteins
• Intermediate Filament Proteins
• Recombinant Proteins

Topics

• Animals
• Dermatitis, Atopic (genetics, metabolism, therapy)
• Dermis (cytology, metabolism)
• Epidermal Cells
• Epidermis (metabolism)
• Filaggrin Proteins
• Genetic Therapy (methods)
• HEK293 Cells
• Humans
• Intermediate Filament Proteins (deficiency, genetics, pharmacokinetics)
• Mice
• Mice, Inbred C57BL
• Mice, Mutant Strains
• Phenotype
• Recombinant Proteins (genetics, pharmacokinetics)