Inhibition of craniosynostosis and premature suture fusion inmutant mice with RNA nanoparticle gene therapy.

Abstract

Craniosynostosis is a common birth defect affecting 1 of the 2200 live births causing severe skull and cognitive defects, due to premature cranial suture fusion. The current surgical treatments require invasive calvaria vault remodeling and cranial bone resection in the baby. We demonstrate that inhibition ofinmice results in coronal suture fusion (craniosynostosis). Therefore, we use overexpression ofto prevent suture fusion inmutant mice, a well-known model for craniosynostosis. We developed a PEGylated-peptide nanoparticle system to deliver plasmid DNA expressingdirectly to the sutures of postnatal day 4 (P4)mutant mice before suture fusion. Injection of thenanoparticles under the scalp before suture fusion at P7 to P10 inhibited suture fusion. Treatments increased Gli1- and Six2-positive suture stem cells and the thickness of the periosteum layer. The treatedmice increased body weight and were alert and active. We demonstrate an effective noninvasive gene therapy treatment for craniosynostosis.