AAV3-Cre

Adeno-associated viruses (AAVs) represent a family of helper-dependent parvoviruses and consist of a single-stranded DNA genome packaged into an icosahedral capsid. The AAV capsid interacts directly with specific host cell receptors. Various AAV serotypes of human and primate origin have been identified (AAV1 to AAV13), which differ in their capsid structure and exhibit different cell or tissue tropisms. AAV-derived vectors are increasingly being used for gene therapy. The differential tropism of the various AAV serotypes is well suited to direct vectors to specific cell types or tissues for gene therapy. For many AAV serotypes, binding to cell surface glycans has been shown to be required for infection. Cell surface glycans are typically attached to proteins (glycoproteins and proteoglycans) or lipids (sphingolipids) of the cell membrane. These carbohydrates are structurally the most complex building blocks of life. The diversity of mammalian glycan biopolymers is achieved through alternating sequences of 10 different monosaccharide building blocks, variable glycosidic bonds, and branching and modifications of the sugars. Furthermore, attachment to different proteins can be achieved through asparagine (N-linked glycans) or serine or threonine (O-linked glycans) residues or lipids. Almost all membrane proteins are glycosylated, but their glycosylation patterns vary in different tissues. They are involved in a variety of cellular processes, including protein folding and signal transduction. In addition, surface-exposed glycans are recognized by various viral families that utilize them as host cell receptors.