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In 2004, Shen et al. developed a safe and efficient gene transfer system using a DNA-apatite composite layer. We have recently succeeded in improving further the gene transfer efficiency by immobilizing a cell adhesion molecule laminin, in a DNA-apatite composite layer. In this study, we showed that not only laminin but fibronectin immobilized in a DNA-apatite composite layer enhances cell adhesion and cell spreading on the layer, thereby markedly improving the gene transfer efficiency. Therefore, the immobilization of a cell adhesion molecule in a DNA-apatite composite layer is crucial for improving the gene transfer efficiency. By using fibronectin instead of laminin and optimizing the condition to prepare the fibronectin-DNA-apatite composite layer, the amount (weight) of cell adhesion molecule required was reduced to approximately one-fourth while retaining the relatively high gene transfer efficiency. It was also shown that the resulting fibronectin-DNA-apatite composite layer prepared under the optimized condition mediated the area-specific gene transfer on its surface, that is, DNA was preferentially transferred to the cells adhering to the surface of the fibronectin-DNA-apatite composite layer. The present gene transfer system with potential for area-specific transfection and advantages of safety and relatively high efficiency would be useful in tissue engineering applications, gene therapy, and production of transfection microarrays.

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Hollow and non-hollow mesoporous silica nanospheres are synthesized and used for cancer vaccine adjuvants. The hollow structure of mesoporous silica nanospheres significantly promote cellular uptake of a model cancer antigen by macrophage-like cells in vitro, improve anti-cancer immunity, CD4(+) and CD8(+) T cell populations in splenocytes of mice in vivo.

4-Hydroxy-2-nonenal (HNE), a major racemic product of lipid peroxidation, preferentially reacts with cysteine residues to form a stable HNE-cysteine Michael addition adduct possessing three chiral centers. Here, to gain more insight into sulfhydryl modification by HNE, we characterized the stereochemical configuration of the HNE-cysteine adducts and investigated their stereoselective formation in redoxregulated proteins. To characterize the HNE-cysteine adducts by NMR, the authentic (R)-HNE-and (S)-HNE-cysteine adducts were prepared by incubating N-acetylcysteine with each HNE enantiomer, both of which provided two peaks in reversed-phase high performance liquid chromatography (HPLC). The NMR analysis revealed that each peak was a mixture of anomeric isomers. In addition, mutarotation at the anomeric center was also observed in the analysis of the nuclear Overhauser effect. To analyze these adducts in proteins, we adapted a pyridylamination-based approach, using 2-aminopyridine in the presence of sodium cyanoborohydride, which enabled analyzing the individual (R)-HNE-and (S)-HNE-cysteine adducts by reversed-phase HPLC following acid hydrolysis. Using the pyridylamination method along with mass spectrometry, we characterized the stereoselective formation of the HNE-cysteine adducts in human thioredoxin and found that HNE preferentially modifies Cys 73 and, to the lesser extent, the active site Cys 32 . More interestingly, the (R)-HNE-and (S)-HNE-cysteine adducts were almost equally formed at Cys 73 , whereas Cys 32 exhibited a remarkable preference for the adduct formation with (R)-HNE. Finally, the utility of the method for the determination of the HNE-cysteine adducts was confirmed by an in vitro study using HeLa cells. The present results not only offer structural insight into sulfhydryl modification by lipid peroxidation products but also provide a platform for the chemical analysis of protein S-associated aldehydes in vitro and in vivo.Lipid peroxidation in tissue and in tissue fractions represents a degradative process, which is the consequence of the production and the propagation of free radical reactions primarily involving membrane polyunsaturated fatty acids and has been implicated in the pathogenesis of numerous diseases, including atherosclerosis, diabetes, cancer, and rheumatoid arthritis, as well as in drug-associated toxicity, post-ischemic reoxygenation injury, and aging (1). The peroxidative breakdown of polyunsaturated fatty acids has also been implicated in the pathogenesis of many types of liver injury and especially in the hepatic damage induced by several toxic substances. Lipid peroxidation leads to the formation of a broad array of different products with diverse and powerful biological activities. Among them is a variety of different aldehydes (2). The primary products of lipid peroxidation, lipid hydroperoxides, can undergo carbon-carbon bond cleavage via alkoxyl radicals in the presence of transition metals giving rise to the formation of short chain, unesterified aldehydes, or a secon...

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