Rezension

Wir besprechen den bisher nur als Teildruck erschienenen Band Mathe.delta 11/12 fürbaden-württembergische Gymnasie

The design of pamanet the paderborn mobile ad-hoc network (Extended Abstract)

Wireless connectivity is state of the art for local area networks. Currently, most W-LAN networks rely on a centralized design with access points routing all inner and outbound traffic. These access points are intrinsic communication bottlenecks. Mobile Ad Hoc Networks (MANET) overcome this problem, because every participant works as well as a simple node and as a router. Current MANETs are restricted in scalability, because they rely on flooding mechanisms or complete routing tables. Other approaches, providing better scalability use clustering, yet network performance deteriorates in case of high node mobility. We describe the design of a PAMANET, the Paderborn Mobile Ad Hoc Network, a MANET overcoming these problems providing scalability and reliability in a mobile scenario. When implemented, PAMANET works with standard W-LAN IEEE 802.11 radio devices, provides IPv6 communication interfaces and works on personal computers under a standard Linux distribution. First, we present current routing protocols and classify them with respect to scalability and stability in dynamically evolving MANETs. Then, we discuss related research in the area of distributed hash tables and consistent hashing, used for relieving hot spots in the Web, storage area networks and peer-to-pee

Hematopoietic stem cell gene therapy for IFNγR1 deficiency protects mice from mycobacterial infections.

Mendelian susceptibility to mycobacterial disease is a rare primary immunodeficiency characterized by severe infections caused by weakly virulent mycobacteria. Biallelic null mutations in genes encoding interferon gamma receptor 1 or 2 (IFNGR1orIFNGR2) result in a life-threatening disease phenotype in early childhood. Recombinant interferon γ (IFN-γ) therapy is inefficient, and hematopoietic stem cell transplantation has a poor prognosis. Thus, we developed a hematopoietic stem cell (HSC) gene therapy approach using lentiviral vectors that expressIfnγr1either constitutively or myeloid specifically. Transduction of mouseIfnγr1 -/- HSCs led to stable IFNγR1 expression on macrophages, which rescued their cellular responses to IFN-γ. As a consequence, genetically corrected HSC-derived macrophages were able to suppress T-cell activation and showed restored antimycobacterial activity againstMycobacterium aviumandMycobacterium bovisBacille Calmette-Guérin (BCG) in vitro. Transplantation of genetically corrected HSCs intoIfnγr1-/-mice before BCG infection prevented manifestations of severe BCG disease and maintained lung and spleen organ integrity, which was accompanied by a reduced mycobacterial burden in lung and spleen and a prolonged overall survival in animals that received a transplant. In summary, we demonstrate an HSC-based gene therapy approach for IFNγR1 deficiency, which protects mice from severe mycobacterial infections, thereby laying the foundation for a new therapeutic intervention in corresponding human patients