title: Preparation and property of a novel bone graft composite consisting of rhBMP-2 loaded PLGA microspheres and calcium phosphate cement.
abstract: Calcium phosphate cement (CPC) is a highly promising bone substitute and an excellent carrier for delivering growth factors. Yet, the lack of macro-porosity and osteoinductive ability, limit its use. This study is aimed at developing a novel biodegradable biomaterial for bone repair with both highly osteoconductive and osteoinductive properties. RhBMP-2 loaded PLGA microspheres were incorporated into rhBMP-2/CPC for macropores for bone ingrowth. The compressive strength, crystallinity, microscopic structure, and bioactivity of the composites were investigated. The results showed that with the incorporation of rhBMP-2 loaded PLGA microspheres, the compressive strength was decreased from (29.48+/-6.42) MPa to (8.26+/-3.58) MPa. X-ray diffraction revealed that the crystallinity pattern of HA formed by CPC had no significant change. Inside the composite, the microspheres distributed homogeneously and contacted intimately with the HA matrix, as observed by scanning electron microscopy (SEM). When the PLGA microspheres dissolved after having been emerged in PBS for 56 days, macropores were created within the CPC. The rhBMP-2/PLGA/CPC composite, showing a 4.9% initial release of rhBMP-2 in 24 h, followed by a prolonged release for 28 days, should have a greater amount of rhBMP-2 released compared to the CPC delivery system. When rabbit marrow stromal cells were cocultured with the composite, the alkaline phosphatase (ALP) and osteocalcin (OC) showed a dose response to the rhBMP-2 released from the composite, indicating that the activity of rhBMP-2 was retained. This study shows that the new composite reveals more rhBMP-2 release and osteogenic activity. This novel BMP/PLGA/CPC composite could be a promising synthetic bone graft in craniofacial and orthopedic repairs.
authors: Institute of Orthopeadics, Xijing Hospital, 4th Military Medical University (FMMU), Changle West Road, Xi'an 710032, China.
authors: Zhengqi
authors: Z
authors: Fei
authors: Yunyu
authors: Y
authors: Hu
authors: Daocheng
authors: D
authors: Wu
authors: Hong
authors: H
authors: Wu
authors: Rong
authors: R
authors: Lu
authors: Jianping
authors: J
authors: Bai
authors: Hongxun
authors: H
authors: Song
mesh_terms: D000818:Animals; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D018786:Bone Substitutes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D002130:Calcium Phosphates / Q000737:chemistry* / Q000494:pharmacology; D002478:Cells, Cultured; D019245:Compressive Strength / Q000187:drug effects; D054855:Drug-Eluting Stents; D005269:Femur / Q000187:drug effects / Q000502:physiology; D019344:Lactic Acid / Q000737:chemistry* / Q000494:pharmacology; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D011100:Polyglycolic Acid / Q000737:chemistry* / Q000494:pharmacology; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011817:Rabbits; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000494:pharmacology; D019279:Resin Cements / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D016212:Transforming Growth Factor beta / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D014961:X-Ray Diffraction
chemical_list: D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D018786:Bone Substitutes; D002130:Calcium Phosphates; D011994:Recombinant Proteins; D019279:Resin Cements; D016212:Transforming Growth Factor beta; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; C020243:calcium phosphate
references: J Biomed Mater Res. 2002 Feb;59(2):265-72
references: 11745562
references: Biomaterials. 2002 Sep;23(17):3673-80
references: 12109693
references: Arch Otolaryngol Head Neck Surg. 1993 Feb;119(2):185-90
references: 8427682
references: J Biomed Mater Res. 2002 Jan;59(1):110-7
references: 11745543
references: J Biomed Mater Res. 2000 Jun 5;50(3):452-62
references: 10737888
references: J Orthop Res. 2002 May;20(3):473-82
references: 12038620
references: Biomaterials. 1989 Sep;10(7):481-8
references: 2804236
references: J Cell Biochem. 2003 Dec 15;90(6):1112-27
references: 14635186
references: Plast Reconstr Surg. 1992 Aug;90(2):174-85; discussion 186-91
references: 1321453
references: Arch Otolaryngol Head Neck Surg. 1991 Apr;117(4):385-9
references: 1848767
references: J Biomed Mater Res A. 2003 Apr 1;65(1):30-6
references: 12635151
references: J Bone Joint Surg Am. 2001;83-A Suppl 1(Pt 2):S105-15
references: 11314788
references: J Mater Sci Mater Med. 1999 Oct-Nov;10(10/11):663-70
references: 15347983
references: J Biomed Mater Res. 2002 Oct;62(1):1-13
references: 12124781
references: Biomol Eng. 2002 Aug;19(2-6):227-31
references: 12202187
references: J Mater Sci Mater Med. 2001 Feb;12(2):135-9
references: 15348319
references: J Biomed Mater Res. 1998 Apr;40(1):139-44
references: 9511108
references: J Orthop Res. 2003 Nov;21(6):997-1004
references: 14554211
references: J Biomed Mater Res. 1999 Dec 5;47(3):324-35
references: 10487883
references: J Biomed Mater Res. 2000 Jun 5;50(3):440-51
references: 10737887
references: Biomaterials. 2004 May;25(11):2123-32
references: 14741627