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Current thalassemia gene therapy protocols require the collection of hematopoietic stem/progenitor cells (HSPCs), in vitro culture, lentivirus vector transduction, and retransplantation into myeloablated patients. Because of cost and technical complexity, it is unlikely that such protocols will be applicable in developing countries, where the greatest demand for a [beta]-thalassemia therapy lies. We have developed a simple in vivo HSPC gene therapy approach that involves HSPC mobilization and an intravenous injection of integrating HDAd5/35++ vectors. Transduced HSPCs homed back to the bone marrow, where they persisted long-term. HDAd5/35++ vectors for in vivo gene therapy of thalassemia had a unique capsid that targeted primitive HSPCs through human CD46, a relatively safe SB100X transposase-based integration machinery, a micro-LCR-driven [gamma]-globin gene, and an MGMT(P140K) system that allowed for increasing the therapeutic effect by short-term treatment with low-dose [O.sup.6]-benzylguanine plus bis-chloroethylnitrosourea. We showed in 'healthy' human CD46-transgenic mice and in a mouse model of thalassemia intermedia that our in vivo approach resulted in stable [gamma]-globin expression in the majority of circulating red blood cells. The high marking frequency was maintained in secondary recipients. In the thalassemia model, a near-complete phenotypic correction was achieved. The treatment was well tolerated. This cost-efficient and 'portable' approach could permit a broader clinical application of thalassemia gene therapy., Introduction Thalassemia is one of the most common inherited diseases in humans worldwide (1), resulting from absent ([beta]O/[beta]O) or deficient ([beta]+/[beta]+) [beta]-globin chain synthesis. Approximately 60,000 children are born annually [...]

We have identified desmoglein-2 (DSG-2) as the primary high-affinity receptor used by adenoviruses Ad3, Ad7, Ad11 and Ad14. These serotypes represent key human pathogens causing respiratory and urinary tract infections. In epithelial cells, adenovirus binding of DSG-2 triggers events reminiscent of epithelial-to-mesenchymal transition, leading to transient opening of intercellular junctions. This opening improves access to receptors, for example, CD46 and Her2/neu, that are trapped in intercellular junctions. In addition to complete virions, dodecahedral particles (PtDds), formed by excess amounts of viral capsid proteins, penton base and fiber during viral replication, can trigger DSG-2- mediated opening of intercellular junctions as shown by studies with recombinant Ad3 PtDds. Our findings shed light on adenovirus biology and pathogenesis and may have implications for cancer therapy., Human adenoviruses have been classified into six species (A to F) with 55 known serotypes. Most adenovirus serotypes use the coxsackie adenovirus receptor (CAR) as a primary attachment receptor (1). [...]

Author(s): Anuj Gaggar [1, 2]; Dmitry M Shayakhmetov [2]; Andre Lieber (corresponding author) [1, 2] Group B adenoviruses, a subgenus of human Adenoviridae, are associated with a variety of often-fatal [...]

Clinical applications of tumor gene therapy require tumor-specific delivery or expression of therapeutic genes in order to maximize the oncolytic index and minimize side effects. This study demonstrates activation of transgene expression exclusively in hepatic metastases after systemic application of a modified first-generation (E1A/E1B-deleted) adenovirus vector (AdE1[sup.-]) in mouse tumor models. The discrimination between tumors and normal liver tissue is based on selective DNA replication of AdE1[sup.-] vectors in tumor cells. This new AdE1[sup.-] based vector system uses homologous recombination between inverted repeats to mediate precise rearrangements within the viral genome. As a result of these rearrangements, a promoter is brought into conjunction with a reporter gene creating a functional expression cassette. Genomic rearrangements are dependent upon viral DNA replication, which in turn occurs specifically in tumor cells. In a mouse tumor model with liver metastases derived from human tumor cells, a single systemic administration of replication activated AdE1[sup.-] vectors achieved transgene expression in every metastasis, whereas no extra-tumoral transgene induction was observed. Here we provide a new concept for tumor-specific gene expression that is also applicable for other conditionally replicating adenovirus vectors., Author(s): Dirk S. Steinwaerder [1]; Cheryl A. Carlson [1, 2]; Desiree L. Otto [3]; Zong-Yi Li [1]; Shaoheng Ni [1]; Andre Lieber (corresponding author) [1] Adenovirus vectors deleted for E1A [...]