The Sleeping Beauty (SB) transposon is a promising technology platform for gene transfer in vertebrates; however, its efficiency of gene insertion can be a bottleneck in primary cell types. A large-scale genetic screen in mammalian cells yielded a hyperactive transposase (SB100X) with approximately 100-fold enhancement in efficiency when compared to the first-generation transposase. SB100X supported 35-50% stable gene transfer in human CD34(+) cells enriched in hematopoietic stem or progenitor cells. Transplantation of gene-marked CD34(+) cells in immunodeficient mice resulted in long-term engraftment and hematopoietic reconstitution. In addition, SB100X supported sustained (>1 year) expression of physiological levels of factor IX upon transposition in the mouse liver in vivo. Finally, SB100X reproducibly resulted in 45% stable transgenesis frequencies by pronuclear microinjection into mouse zygotes. The newly developed transposase yields unprecedented stable gene transfer efficiencies following nonviral gene delivery that compare favorably to stable transduction efficiencies with integrating viral vectors and is expected to facilitate widespread applications in functional genomics and gene therapy.

Development of a vaccine against H. pylori is regarded as desirable alternative to the current antibiotic therapy regimens. Mice immunized with an attenuated recombinant Salmonella typhimurium expressing H. pylori urease subunits A&B have dramatically reduced bacterial loads after a single dose. The mechanism(s) of protection against this largely extra-cellular pathogen are not fully understood. The aim of this study was to identify genes that were regulated specifically in response to immunization, in order to gain a broader picture of the immune response in the immunized gastric epithelium. Gene expression in RNA isolated from the gastric mucosa of immunized and infected Balb/c mice was compared with that in infected only mice at 1, 3, and 14 days after challenge with a mouse-adapted strain of H. pylori. We show that infection with H. pylori causes an immediate reaction in vivo, which was clearly divided into acute and chronic phases, and further that the transcriptional response in the H. pylori infected and immunized gastric mucosa is unique. Analysis of gene expression patterns at day 14 post-infection suggested not only the beginning of a lymphocytic infiltrate, but of an integrated epithelial response characterized by increased expression of genes controlling cell cycle and turnover. This observation was confirmed in independent experiments. The global approach has brought new insights to the effect of immunization on the gastric epithelium and has led us to propose a new multi-factorial model for the mechanisms underlying vaccine-induced protection.

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Objective-Functionally interactive proteases of the plasminogen/plasmin and the matrix metalloproteinase (MMP) system degrade and reorganize the extracellular matrix of the vessel wall in atherosclerosis. Here we investigated whether such proteases are able to confer atherogenic properties onto low density lipoprotein by nonoxidative modification. Methods and Results-Similar to the recently described enzymatically-modified low-density lipoprotein (E-LDL), native LDL exposed to plasmin or matrix MMP-2 or MMP-9 and cholesterylester-hydrolase (CEH) showed extensive deesterification, with ratios of free cholesterol to total cholesterol rising to 0.8 compared with 0.2 in native LDL. When the ratio exceeded 0.6, both plasmin/CEH-LDL and MMP/CEH-LDL fused into larger particles. In parallel, they gained C-reactive protein-dependent complement-activating capacity. E-LDL produced with any protease/CEH combination was efficiently taken up by human macrophages, whereby marked induction of MMP-2 expression by E-LDL was observed. These in vitro findings had their in vivo correlates: urokinase-type plasminogen activator, MMP-2, and MMP-9 were detectable in both early and advanced human atherosclerotic lesions in colocalization with E-LDL. Conclusions-Plasmin and MMP-2/MMP-9 may not only be involved in remodeling of the extracellular matrix in progressing plaques, but they may also be involved in lipoprotein modification during genesis and progression of atherosclerotic lesions. Key Words: atherosclerosis Ⅲ lipoproteins Ⅲ macrophages Ⅲ metalloproteinases Ⅲ plasminogen activators I t is widely held that atherogenesis is triggered by enhanced entrapment of low-density lipoprotein (LDL) in the intima, which is followed by its uptake by macrophages. Both oxidative and nonoxidative processes can generate potentially atherogenic LDL derivatives. 1 We are pursuing the concept that enzymatic remodeling of the lipoprotein is a key modification, because proteolytic cleavage of apolipoprotein B (apoB) in conjunction with hydrolysis of cholesteryl esters generates lipoprotein particles that are similar to lesionderived LDL in structure, biological properties, and composition. 2,3 Enzymatically-remodeled LDL (E-LDL) binds C-reactive protein (CRP) and activates complement. 4 E-LDL induces foam cell formation in monocytes, 5 macrophages, 3 and smooth muscle cells, 6 stimulates MCP-1 production, 7 and directly promotes adhesion and transmigration of monocytes through endothelial cell monolayers. 8 These in vitro findings have their in vivo correlates: immunohistological analyses with specific monoclonal antibodies (mAbs) have revealed extensive extracellular deposits of E-LDL at the early stages of atherosclerotic lesion formation. 9 CRP and activated complement components are also present in colocalization with E-LDL. 4,9 Like in vitro-generated E-LDL, lesioned LDL has a high content of free cholesterol; 10 -12 therefore, it is apparent that extensive deesterification of cholesteryl esters must indeed occur in the lesions.We used trypsin in c...