RESUMO
A promising direction for the replacement of expanded bone defects is the development of bioimplants based on synthetic biocompatible materials impregnated with growth factors that stimulate bone remodeling. Novel biomimetic highly porous ultra-high molecular weight polyethylene (UHMWPE)/40% hydroxyapatite (HA) scaffold for reconstructive surgery with the porosity of 85 ± 1% vol. and a diameter of pores in the range of 50-800 µm was developed. The manufacturing process allowed the formation of trabecular-like architecture without additional solvents and thermo-oxidative degradation. Biomimetic UHMWPE/HA scaffold was biocompatible and provided effective tissue ingrowth on a model of critical-sized cranial defects in mice. The combined use of UHMWPE/HA with Bone Morphogenetic Protein-2 (BMP-2) demonstrated intensive mineralized bone formation as early as 3 weeks after surgery. The addition of erythropoietin (EPO) significantly enhanced angiogenesis in newly formed tissues. The effect of EPO of bacterial origin on bone tissue defect healing was demonstrated for the first time. The developed biomimetic highly porous UHMWPE/HA scaffold can be used separately or in combination with rhBMP-2 and EPO for reconstructive surgery to solve the problems associated with difference between implant architecture and trabecular bone, low osteointegration and bioinertness.
Assuntos
Materiais Biocompatíveis/química , Doenças Ósseas/cirurgia , Proteína Morfogenética Óssea 2/química , Durapatita/química , Eritropoetina/química , Polietilenos/química , Fator de Crescimento Transformador beta/química , Animais , Materiais Biocompatíveis/farmacologia , Doenças Ósseas/terapia , Proteína Morfogenética Óssea 2/metabolismo , Proteína Morfogenética Óssea 2/farmacologia , Proteína Morfogenética Óssea 2/uso terapêutico , Regeneração Óssea/efeitos dos fármacos , Osso e Ossos/patologia , Osso e Ossos/fisiologia , Portadores de Fármacos/química , Eritropoetina/metabolismo , Eritropoetina/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Nanocompostos/química , Neovascularização Fisiológica/efeitos dos fármacos , Porosidade , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Procedimentos de Cirurgia Plástica , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Fator de Crescimento Transformador beta/uso terapêuticoRESUMO
BACKGROUND: E protein of tick-borne encephalitis virus (TBEV) and other flaviviruses is located on the surface of the viral particle. Domain III of this protein seems to be a promising component of subunit vaccines for prophylaxis of TBE and kits for diagnostics of TBEV. METHODS: Three variants of recombinant TBEV E protein domain III of European, Siberian and Far Eastern subtypes fused with dextran-binding domain of Leuconostoc citreum KM20 were expressed in E. coli and purified. The native structure of domain III was confirmed by ELISA antibody kit and sera of patients with tick-borne encephalitis. Immunogenic and protective properties of the preparation comprising these recombinant proteins immobilized on a dextran carrier with CpG oligonucleotides as an adjuvant were investigated on the mice model. RESULTS: All 3 variants of recombinant proteins immobilized on dextran demonstrate specific interaction with antibodies from the sera of TBE patients. Thus, constructed recombinant proteins seem to be promising for TBE diagnostics. The formulation comprising the 3 variants of recombinant antigens immobilized on dextran and CpG oligonucleotides, induces the production of neutralizing antibodies against TBEV of different subtypes and demonstrates partial protectivity against TBEV infection. CONCLUSIONS: Studied proteins interact with the sera of TBE patients, and, in combination with dextran and CPGs, demonstrate immunogenicity and limited protectivity on mice compared with reference "Tick-E-Vac" vaccine.
