No abstract

Although it is widely accepted that specific intracellular receptor proteins are involved in the oestrogenic regulation of gene expression and growth in reproductive tissues, the precise nature of the regulation is poorly understood. Among the unresolved issues are the distribution and dynamics of the oestrogen receptor protein (oestrophilin) in target tissues in the presence and absence of oestrogens and antioestrogens. The use of radiolabelled and unlabelled receptor ligands to detect and measure oestrogen receptors in tissues has been complicated by the presence of other intracellular steroid-binding proteins and by the low concentration of receptors in responsive tissues. We report here the development of an immunocytochemical procedure that is suitable for localizing oestrophilin directly in frozen tissue sections or cells from human and several non-human sources. When monoclonal antibodies to oestrophilin were used to detect receptor in various oestrogen-sensitive tissues, specific staining was confined to the nucleus of all stained cells, suggesting that both cytosol and nuclear forms of the receptor protein may reside in the nuclear compartment.

Biomaterial scaffolds have been extensively used to deliver growth factors to induce new bone formation. The pharmacokinetics of growth factor delivery has been a critical regulator of their clinical success. This review will focus on the surface interactions that control the non-covalent incorporation of growth factors into scaffolds and the mechanisms that control growth factor release from clinically relevant biomaterials. We will focus on the delivery of recombinant human bone morphogenetic protein-2 from materials currently used in the clinical practice, but also suggest how general mechanisms that control growth factor incorporation and release delineated with this growth factor could extend to other systems. A better understanding of the changing mechanisms that control growth factor release during the different stages of preclinical development could instruct the development of future scaffolds for currently untreatable injuries and diseases.

No abstract