RESUMO
There is increasing interest in new biomaterials and new culture methods for bone tissue engineering, in order to produce, in vitro, living constructs able to integrate in the surrounding tissue. Using an electromagnetic bioreactor (magnetic field intensity, 2 mT; frequency, 75 Hz), we investigated the effects of electromagnetic stimulation on SAOS-2 human osteoblasts seeded onto a porous polyurethane. In comparison with control conditions, the electromagnetic stimulation caused higher cell proliferation, increased surface coating with decorin and type-I collagen, and higher calcium deposition. The immunolocalization of decorin and type-I collagen showed their colocalization in the cell-rich areas. The use of an electromagnetic bioreactor aimed at obtaining the surface modification of the porous polyurethane in terms of cell colonization and coating with calcified matrix. The superficially modified biomaterial could be used, in clinical applications, as an implant for bone repair.
Assuntos
Reatores Biológicos , Técnicas de Cultura de Células , Estimulação Elétrica , Campos Eletromagnéticos , Osteoblastos/química , Poliuretanos , Engenharia Tecidual/métodos , Cálcio , Proliferação de Células , Colágeno Tipo I/química , Decorina , Matriz Extracelular , Proteínas da Matriz Extracelular , Humanos , Imuno-Histoquímica , ProteoglicanasRESUMO
Therapy for neurodegenerative lysosomal Tay-Sachs (TS) disease requires active hexosaminidase (Hex) A production in the central nervous system and an efficient therapeutic approach that can act faster than human disease progression. We combined the efficacy of a non-replicating Herpes simplex vector encoding for the Hex A alpha-subunit (HSV-T0alphaHex) and the anatomic structure of the brain internal capsule to distribute the missing enzyme optimally. With this gene transfer strategy, for the first time, we re-established the Hex A activity and totally removed the GM2 ganglioside storage in both injected and controlateral hemispheres, in the cerebellum and spinal cord of TS animal model in the span of one month's treatment. In our studies, no adverse effects were observed due to the viral vector, injection site or gene expression and on the basis of these results, we feel confident that the same approach could be applied to similar diseases involving an enzyme defect.