RESUMO
Surface functionalization of hydroxyapatite (HA) and beta-tricalcium phosphate (TCP) bioceramics with chemical ligands containing a pyrrogallol moiety was developed to improve the adhesion of bone cell precursors to the biomaterials. Fast and biocompatible copper-free click reaction with azido-modified human fetal osteoblasts resulted in improved cell binding to both HA and TCP bioceramics, opening the way for using this methodology in the preparation of cell-engineered bone implants.
Assuntos
Materiais Biocompatíveis/química , Fosfatos de Cálcio/química , Adesão Celular , Cerâmica/química , Durapatita/química , Feto/metabolismo , Osteoblastos/metabolismo , Materiais Biocompatíveis/metabolismo , Fosfatos de Cálcio/metabolismo , Proliferação de Células , Células Cultivadas , Cerâmica/metabolismo , Química Click , Durapatita/metabolismo , Feto/citologia , Humanos , Teste de Materiais , Estrutura Molecular , Osteoblastos/citologia , Propriedades de SuperfícieRESUMO
Bone substitute materials allowing trans-scaffold migration and in-scaffold survival of human bone-derived cells are mandatory for development of cell-engineered permanent implants to repair bone defects. In this study, we evaluated the influence on human bone-derived cells of the material composition and microstructure of foam scaffolds of calcium aluminate. The scaffolds were prepared using a direct foaming method allowing wide-range tailoring of the microstructure for pore size and pore openings. Human fetal osteoblasts (osteo-progenitors) attached to the scaffolds, migrated across the entire bioceramic depending on the scaffold pore size, colonized, and survived in the porous material for at least 6 weeks. The long-term biocompatibility of the scaffold material for human bone-derived cells was evidenced by in-scaffold determination of cell metabolic activity using a modified MTT assay, a repeated WST-1 assay, and scanning electron microscopy. Finally, we demonstrated that the osteo-progenitors can be covalently bound to the scaffolds using biocompatible click chemistry, thus enhancing the rapid adhesion of the cells to the scaffolds. Therefore, the different microstructures of the foams influenced the migratory potential of the cells, but not cell viability. Scaffolds allow covalent biocompatible chemical binding of the cells to the materials, either localized or widespread integration of the scaffolds for cell-engineered implants.
Assuntos
Substitutos Ósseos/química , Cerâmica/química , Feto/citologia , Osteoblastos/química , Alicerces Teciduais/química , Compostos de Alumínio/química , Substitutos Ósseos/síntese química , Compostos de Cálcio/química , Adesão Celular , Proliferação de Células , Células Cultivadas , Química Click , Humanos , Estrutura Molecular , Osteoblastos/citologia , Osteoblastos/metabolismo , Porosidade , Propriedades de SuperfícieRESUMO
To control the selective adhesion of human endothelial cells and human serum proteins to bioceramics of different compositions, a multifunctional ligand containing a cyclic arginine-glycine-aspartate (RGD) peptide, a tetraethylene glycol spacer, and a gallate moiety was designed, synthesized, and characterized. The binding of this ligand to alumina-based, hydroxyapatite-based, and calcium phosphate-based bioceramics was demonstrated. The conjugation of this ligand to the bioceramics induced a decrease in the nonselective and integrin-selective binding of human serum proteins, whereas the binding and adhesion of human endothelial cells was enhanced, dependent on the particular bioceramics.
Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Cerâmica/química , Cerâmica/farmacologia , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Engenharia Tecidual/métodos , Óxido de Alumínio/química , Materiais Biocompatíveis/síntese química , Fosfatos de Cálcio/química , Adesão Celular/efeitos dos fármacos , Cerâmica/síntese química , Durapatita/química , Etilenoglicol/química , Ácido Gálico/química , Humanos , Ligantes , Oligopeptídeos/química , Propriedades de SuperfícieRESUMO
Different anchoring groups have been studied with the aim of covalently binding organic linkers to the surface of alumina ceramic foams. The results suggested that a higher degree of functionalization was achieved with a pyrogallol derivative--as compared to its catechol analogue--based on the XPS analysis of the ceramic surface. The conjugation of organic ligands to the surface of these alumina materials was corroborated by DNP-MAS NMR measurements.
RESUMO
The chemical functionalization of cell-surface proteins of human primary fetal bone cells with hydrophilic bioorthogonal intermediates was investigated. Toward this goal, chemical pathways were developed for click reaction-mediated coupling of alkyne derivatives with cellular azido-expressing proteins. The incorporation via a tetraethylene glycol linker of a dipeptide and a reporter biotin allowed the proof of concept for the introduction of cell-specific peptide ligands and allowed us to follow the reaction in living cells. Tuning the conditions of the click reaction resulted in chemical functionalization of living human fetal osteoblasts with excellent cell survival.
Assuntos
Alcinos/química , Química Click , Proteínas de Membrana/química , Osteoblastos/citologia , Membrana Celular/química , Sobrevivência Celular , Células Cultivadas , Feto/citologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Osteoblastos/química , Engenharia Tecidual/métodosRESUMO
New oxathiazinane dioxides have been derived from D- and L-serine and tested for their in vitro cell growth inhibitory activity toward SKBR3 breast cancer cells. (5R)-5-(4-(4'-Bromomethyl)phenyl)benzyloxymethyl-[1,3,4]-oxathiazinane-3,3-dioxide showed a cytotoxicity of IC(50) approximately 10 microM.
