Bone morphogenetic protein-2 sustained delivery by hydrogels with microspheres repairs rabbit mandibular defects

Abstract

Mandible defect is a difficult issue in dental surgery owing to limited therapeutic options. Recombinant human bone morphogenetic protein-2 (rhBMP2) is osteoinductive in bone regeneration. This article prepared chitosan/collagen hydrogels with rhBMP2-incorporated gelatin microsphere (GMs) for a sustained release of rhBMP2 to induce bone regeneration in rabbits. In experiments, mandibular defects of 8 mm in diameter and 3 mm in depth were surgically prepared on the right cheek of 27 rabbits. Either chitosan/collagen hydrogels alone, rhBMP2-incorporated hydrogels, or hydrogels with rhBMP2-incorporated GMs were implanted to the defect sites. The animals were euthanized at 2, 6, 12 weeks following surgery. In results, scanning electronic microscope images revealled spherical GMs. The complex delivery systems, hydrogels with rhBMP2-incorporated GMs, exhibited ideal release profiles in vitro. The complex delivery systems resulted in apparent new bone formation within 12 weeks, as evidenced by computed tomography and histological observations. All these results demonstrated that the chitosan/collagen hydrogels with rhBMP2-incorporated GMs had a better capacity to heal mandible defects than other two hydrogel scaffolds. Chitosan/collagen hydrogels with rhBMP2-incorporated GMs might be potential carriers of rhBMP2 for accelerating the repair of mandibular defects.

Oral Immunization of FMDV Vaccine Using pH-Sensitive and Mucoadhesive Thiolated Cellulose Acetate Phthalate Microparticles

“…However, degradation of antigen in acidic stomach and enzymatic condition, low oral bioavailability and short residence time of antigen at target site make oral vaccination very difficult [10]. Therefore, orally administered vaccine requires protection from the harsh gastric condition and long residence time of vaccine at mucosal site [8,11,12]. Bifunctional polymers having pH-sensitivity and mucoadhesivity have been used as effective carriers for oral vaccination.…”

Synthesis and Biocompatibility Characterizations of in Situ Chondroitin Sulfate–Gelatin Hydrogel for Tissue Engineering

“…11 Inflammatory response of the 10% CS-gelatin hydrogel as measured by the nitric oxide assay TCEP was in advance separately sterilized and the fabricated gels was targeted to be applied directly into a patient, thus no reason going back to the processes of drying, swelling and injection of the hydrogel fabricated. Applications of release of bioactive molecules from tissue engineering scaffold were recently reported in bone, cartilage [32] and other tissues by using scaffold and hydrogel with deliveries of in vitro platelet rich plasma and in vivo bone morphogenic protein-2 (BMP-2), respectively [33,34]. In vitro biological effectiveness of chitosan microparticles cross-linked with sodium triphosphate with activated pure platelet-rich plasma was employed as an injectable composite scaffold for growth factors release, cell proliferation and osteogenic differentiation [33].…”

Membranes for Guided Tissue Regeneration - An Update

“…The release system can be classified into monodrug and multidrug delivery system based on the number of drugs to be delivered. Various monodrug delivery system incorporating growth factors like stromal-cell-derived factor 1 (SDF-1) [50], rhGDF-5/beta TCP [51] and BMP-2 [52] has been developed to facilitate recruitment of host mesenchymal and hematopoietic stem cells and bone regeneration.…”