title: In vitro and in vivo evaluation of the marine sponge skeleton as a bone mimicking biomaterial.
abstract: This investigation was carried out to identify and characterize marine sponges as potential bioscaffolds in bone tissue engineering. The marine sponge (Biemna fortis) samples were collected from the rocky intertidal region of Anjuna, Goa, India, freeze-dried and converted to pure cristobalite at low temperature. After thorough evaluation of sponge samples by DTA-TGA thermography, XRD, FTIR, SEM and cell cytotoxicity by MTT assay, bare sponge scaffolds were fabricated by firing at 1190 °C. These scaffolds were loaded with growth factors (IGF-1 and BMP-2), checked for quasi-dynamic in vitro release kinetics and finally implanted into femoral bone defects in rabbits for up to 90 days, by keeping an empty defect as a control. The in vivo bone healing process was evaluated and compared using chronological radiology, histology, SEM and fluorochrome labeling studies. SEM revealed that the sponge skeleton possesses a collagenous fibrous network consisting of highly internetworked porosity in the size range of 10-220 μm. XRD and FTIR analysis showed a cristobalite phase with acicular crystals of high aspect ratio, and crystallinity was found to increase from 725 to 1190 °C. MTT assay demonstrated the non-cytotoxicity of the samples. A combination of burst and sustained release profile was noticed for both the growth factors and about 74.3% and 83% total release at day 28. In the radiological, histological, scanning electron microscopy and fluorochrome labeling analysis, the IGF-1 impregnated converted sponge scaffold promoted excellent osseous tissue formation followed by the BMP-2 loaded and bare one. These observations suggest that the marine sponge alone and in combination with growth factors is a promising biomaterial for bone repair and bone augmentation.
authors.affiliation: Department of Veterinary Surgery and Radiology, West Bengal University of Animal and Fishery Sciences, Kolkata, India. samitnandi1967@gmail.com.
authors.forename: Samit K
authors.initials: SK
authors.lastname: Nandi
authors.forename: Biswanath
authors.initials: B
authors.lastname: Kundu
authors.forename: Arnab
authors.initials: A
authors.lastname: Mahato
authors.forename: Narsinh L
authors.initials: NL
authors.lastname: Thakur
authors.forename: Siddhartha N
authors.initials: SN
authors.lastname: Joardar
authors.forename: Biman B
authors.initials: BB
authors.lastname: Mandal
mesh_terms: D016475:3T3 Cells; D000818:Animals; D055396:Bone Morphogenetic Protein 2 / Q000008:administration & dosage; D016723:Bone Remodeling; D018786:Bone Substitutes / Q000737:chemistry*; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D007334:Insulin-Like Growth Factor I / Q000008:administration & dosage; D008297:Male; D008422:Materials Testing; D051379:Mice; D008855:Microscopy, Electron, Scanning; D010012:Osteogenesis; D011161:Porifera / Q000737:chemistry* / Q000648:ultrastructure; D011817:Rabbits; D011994:Recombinant Proteins / Q000008:administration & dosage; D017550:Spectroscopy, Fourier Transform Infrared; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; D018786:Bone Substitutes; C583557:IGF1 protein, human; D011994:Recombinant Proteins; D007334:Insulin-Like Growth Factor I