Bone regeneration using moldable calcium phosphate with and without recombinant human BMP-2 in a rabbit critical-sized metaphyseal core defect model

Abstract Background Moldable calcium phosphate (MCaP) biomaterials have been studied as osteoconductive scaffolds for bone regeneration. However, their potential as carriers for recombinant human bone morphogenetic protein-2 (rhBMP-2) and the biological impact of varying rhBMP-2 doses remain to be f...

Full description

Saved in:
Bibliographic Details
Main Authors: Hyun Seung Ryu, Hyun Jung Park, Mi Young Ryu, Young-Hoon Kim, Sang-Il Kim, Hyung-Youl Park
Format: Article
Language:English
Published: BMC 2025-06-01
Series:Journal of Orthopaedic Surgery and Research
Subjects:
Online Access:https://doi.org/10.1186/s13018-025-05966-y
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850224372578516992
author Hyun Seung Ryu
Hyun Jung Park
Mi Young Ryu
Young-Hoon Kim
Sang-Il Kim
Hyung-Youl Park
author_facet Hyun Seung Ryu
Hyun Jung Park
Mi Young Ryu
Young-Hoon Kim
Sang-Il Kim
Hyung-Youl Park
author_sort Hyun Seung Ryu
collection DOAJ
description Abstract Background Moldable calcium phosphate (MCaP) biomaterials have been studied as osteoconductive scaffolds for bone regeneration. However, their potential as carriers for recombinant human bone morphogenetic protein-2 (rhBMP-2) and the biological impact of varying rhBMP-2 doses remain to be fully validated. This study aimed to evaluate the efficacy and safety of MCaP alone and in combination with rhBMP-2 in a rabbit metaphyseal bone defect model. Methods Bilateral critical-sized metaphyseal core defects were created in the distal femurs of 73 skeletally mature female New Zealand White rabbits. Animals were assigned to six groups: sham, autograft, MCaP alone, or MCaP combined with low (0.04 mg/cc), mid (0.16 mg/cc), or high (0.6 mg/cc) doses of rhBMP-2. Bone formation and healing were assessed at 3 days and 3, 6, and 12 weeks using radiography, microcomputed tomography (μCT), histomorphometry, and histopathology. Local tissue reactions were evaluated according to ISO 10993–6 standards, and systemic toxicity was assessed through distant organ examinations. Results Radiographic and μCT analyses showed progressive bone formation in all treatment groups. Compared with autografts, both the MCaP and rhBMP-2-treated groups exhibited significantly higher bone in the region of interest at 6 and 12 weeks (p < 0.05), with no significant differences between the MCaP-only and rhBMP-2 groups. Histological evaluation revealed earlier and more active bone regeneration in rhBMP-2–treated groups, particularly at higher doses. Minimal inflammatory responses were observed across all groups, and no systemic toxicity was detected, supporting the biocompatibility and safety of MCaP-based constructs. Conclusions The MCaP carrier demonstrated strong osteoconductive potential and was sufficient to support bone healing compared to autograft in a metaphyseal defect model. The addition of rhBMP-2 promoted earlier bone formation. However, long-term studies in more challenging bone healing environments are warranted to further assess the clinical utility of rhBMP-2 in bone regeneration.
format Article
id doaj-art-d8e02537d1bb4508a961d56390bcd46b
institution OA Journals
issn 1749-799X
language English
publishDate 2025-06-01
publisher BMC
record_format Article
series Journal of Orthopaedic Surgery and Research
spelling doaj-art-d8e02537d1bb4508a961d56390bcd46b2025-08-20T02:05:38ZengBMCJournal of Orthopaedic Surgery and Research1749-799X2025-06-0120111410.1186/s13018-025-05966-yBone regeneration using moldable calcium phosphate with and without recombinant human BMP-2 in a rabbit critical-sized metaphyseal core defect modelHyun Seung Ryu0Hyun Jung Park1Mi Young Ryu2Young-Hoon Kim3Sang-Il Kim4Hyung-Youl Park5Department of Research Center, CGBio Co., Ltd.Department of Research Center, CGBio Co., Ltd.Department of Research Center, CGBio Co., Ltd.Department of Orthopedic Surgery, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of KoreaDepartment of Orthopedic Surgery, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of KoreaDepartment of Orthopedic Surgery, Eunpyeong St. Mary’s Hospital, College of Medicine, The Catholic University of KoreaAbstract Background Moldable calcium phosphate (MCaP) biomaterials have been studied as osteoconductive scaffolds for bone regeneration. However, their potential as carriers for recombinant human bone morphogenetic protein-2 (rhBMP-2) and the biological impact of varying rhBMP-2 doses remain to be fully validated. This study aimed to evaluate the efficacy and safety of MCaP alone and in combination with rhBMP-2 in a rabbit metaphyseal bone defect model. Methods Bilateral critical-sized metaphyseal core defects were created in the distal femurs of 73 skeletally mature female New Zealand White rabbits. Animals were assigned to six groups: sham, autograft, MCaP alone, or MCaP combined with low (0.04 mg/cc), mid (0.16 mg/cc), or high (0.6 mg/cc) doses of rhBMP-2. Bone formation and healing were assessed at 3 days and 3, 6, and 12 weeks using radiography, microcomputed tomography (μCT), histomorphometry, and histopathology. Local tissue reactions were evaluated according to ISO 10993–6 standards, and systemic toxicity was assessed through distant organ examinations. Results Radiographic and μCT analyses showed progressive bone formation in all treatment groups. Compared with autografts, both the MCaP and rhBMP-2-treated groups exhibited significantly higher bone in the region of interest at 6 and 12 weeks (p < 0.05), with no significant differences between the MCaP-only and rhBMP-2 groups. Histological evaluation revealed earlier and more active bone regeneration in rhBMP-2–treated groups, particularly at higher doses. Minimal inflammatory responses were observed across all groups, and no systemic toxicity was detected, supporting the biocompatibility and safety of MCaP-based constructs. Conclusions The MCaP carrier demonstrated strong osteoconductive potential and was sufficient to support bone healing compared to autograft in a metaphyseal defect model. The addition of rhBMP-2 promoted earlier bone formation. However, long-term studies in more challenging bone healing environments are warranted to further assess the clinical utility of rhBMP-2 in bone regeneration.https://doi.org/10.1186/s13018-025-05966-yBone regenerationCritical-sized defectMetaphyseal boneMoldable calcium phosphateRecombinant human bone morphogenetic protein-2 (rhBMP-2)Bone graft substitute
spellingShingle Hyun Seung Ryu
Hyun Jung Park
Mi Young Ryu
Young-Hoon Kim
Sang-Il Kim
Hyung-Youl Park
Bone regeneration using moldable calcium phosphate with and without recombinant human BMP-2 in a rabbit critical-sized metaphyseal core defect model
Journal of Orthopaedic Surgery and Research
Bone regeneration
Critical-sized defect
Metaphyseal bone
Moldable calcium phosphate
Recombinant human bone morphogenetic protein-2 (rhBMP-2)
Bone graft substitute
title Bone regeneration using moldable calcium phosphate with and without recombinant human BMP-2 in a rabbit critical-sized metaphyseal core defect model
title_full Bone regeneration using moldable calcium phosphate with and without recombinant human BMP-2 in a rabbit critical-sized metaphyseal core defect model
title_fullStr Bone regeneration using moldable calcium phosphate with and without recombinant human BMP-2 in a rabbit critical-sized metaphyseal core defect model
title_full_unstemmed Bone regeneration using moldable calcium phosphate with and without recombinant human BMP-2 in a rabbit critical-sized metaphyseal core defect model
title_short Bone regeneration using moldable calcium phosphate with and without recombinant human BMP-2 in a rabbit critical-sized metaphyseal core defect model
title_sort bone regeneration using moldable calcium phosphate with and without recombinant human bmp 2 in a rabbit critical sized metaphyseal core defect model
topic Bone regeneration
Critical-sized defect
Metaphyseal bone
Moldable calcium phosphate
Recombinant human bone morphogenetic protein-2 (rhBMP-2)
Bone graft substitute
url https://doi.org/10.1186/s13018-025-05966-y
work_keys_str_mv AT hyunseungryu boneregenerationusingmoldablecalciumphosphatewithandwithoutrecombinanthumanbmp2inarabbitcriticalsizedmetaphysealcoredefectmodel
AT hyunjungpark boneregenerationusingmoldablecalciumphosphatewithandwithoutrecombinanthumanbmp2inarabbitcriticalsizedmetaphysealcoredefectmodel
AT miyoungryu boneregenerationusingmoldablecalciumphosphatewithandwithoutrecombinanthumanbmp2inarabbitcriticalsizedmetaphysealcoredefectmodel
AT younghoonkim boneregenerationusingmoldablecalciumphosphatewithandwithoutrecombinanthumanbmp2inarabbitcriticalsizedmetaphysealcoredefectmodel
AT sangilkim boneregenerationusingmoldablecalciumphosphatewithandwithoutrecombinanthumanbmp2inarabbitcriticalsizedmetaphysealcoredefectmodel
AT hyungyoulpark boneregenerationusingmoldablecalciumphosphatewithandwithoutrecombinanthumanbmp2inarabbitcriticalsizedmetaphysealcoredefectmodel