Craniosynostosis is the premature fusion of cranial sutures, which can result in progressive cranial deformations, increased intracranial pressure, and restricted brain growth. Most cases of
craniosynostosis require surgical reconstruction of the cranial vault with the goal of increasing the intracranial volume and correcting the craniofacial
deformities. However, patients often experience rapid post-operative bone regrowth, known as re-
synostosis, which necessitates additional surgical intervention.
Bone morphogenetic protein (BMP) inhibitors have tremendous potential to treat re-
synostosis, but the realization of a clinically viable inhibitor-based therapeutic requires the development of a delivery vehicle that can localize the release to the site of administration. Here, we present an in situ rapidly crosslinking
injectable hydrogel that has the properties necessary to encapsulate co-administered
proteins and demonstrate that the delivery of rmGremlin1 via our
hydrogel system delays bone regrowth in a weanling mouse model of re-
synostosis. Our
hydrogel is composed of two mutually reactive poly(
ethylene glycol) macromolecules, which when mixed crosslink via a bio-orthogonal Cu free click reaction.
Hydrogels containing Gremlin caused a dose dependent inhibition of bone regrowth. In addition to craniofacial applications, our
injectable click
hydrogel has the potential to provide customizable
protein, small molecule, and cell delivery to any site accessible via needle or
catheter.