Intraosseous Delivery of Bone Morphogenic Protein-2 Using a Self-Assembling Peptide Hydrogel

Area of Science:

• Biomaterials Science
• Orthopedic Surgery
• Regenerative Medicine

Background:

• Osteonecrosis of the femoral head (ONFH) causes hip deformity and osteoarthritis.
• Local delivery of bone morphogenic protein-2 (BMP-2) shows promise for ONFH treatment.
• Previous BMP-2 infusions led to uncontrolled spread and heterotopic ossification.

Purpose of the Study:

• To evaluate RADA16 hydrogel as a delivery vehicle for BMP-2 in ONFH.
• To assess RADA16's ability to prevent backflow and control BMP-2 release within the femoral head.

Main Methods:

• Intraosseous infusion of RADA16 hydrogel with radiocontrast agent into cadaver pig femoral heads.
• Microcomputed tomography analysis to assess backflow and distribution.
• In vitro studies to evaluate BMP-2 release kinetics, bioactivity, and cell proliferation on RADA16.

Main Results:

• RADA16 significantly reduced radiocontrast backflow compared to soluble infusion.
• RADA16 hydrogel demonstrated good distribution within the femoral head.
• Higher RADA16 concentrations reduced BMP-2 dissemination; released BMP-2 retained bioactivity.
• RADA16 hydrogels supported pig bone marrow stromal cell proliferation in vitro.

Conclusions:

• RADA16 hydrogel is a promising injectable vehicle for localized BMP-2 delivery to the femoral head.
• This approach may offer a novel therapeutic strategy for ONFH patients.
• RADA16 hydrogel controls BMP-2 release, minimizes off-target effects, and supports cell growth.