Intracellularly selected recombinant antibodies targeting β Amyloid Oligomers

Targeting beta Amyloid (Aβ) peptide, in relation to the degenerative processes of Alzheimer Disease (AD), and studying the mechanisms of Aβ misfolding, oligomerization and aggregation are currently two hot-topics in AD research. Both these aspects can be preferentially approached by the use of anti-Aβ antibodies, in particular of those which are conformation specific, as demonstrated by in vitro studies and by in vivo immunotherapy. Here, we describe the generation of a large panel of anti-Aβ scFvs recombinant antibodies, exploiting a novel in vivo, yeast two hybrid-based, approach developed in our laboratory: the “Intracellular Antibody Capture Technology” (IACT). In this way, we have selected and characterized a panel of 18 different anti-Aβ scFvs, which show interesting features in vitro and in cells. IACT-selected anti-Aβ scFvs are conformation specific versus Aβ oligomers and show peculiar immunoreactivity pattern versus the in vivo produced Aβ deposits in human AD brains. Moreover, our anti-Aβ scFvs, being in vivo selected in the yeast cytoplasm, can be readily expressed as intracellular antibodies in mammalian cells, targeted to different cellular compartments, allowing new promising strategies to study the emerging role of intracellular Aβ processing and oligomerization in AD pathology. The panel of IACT-selected scFvs under study represents a new tool in the survey of existing anti-Aβ antibodies, and the unique characteristics of the selection strategy used for their isolation appear to be particularly suited for the selection of oligomeric specific anti-Aβ antibodies. Furthermore, the recombinant nature of the antibodies makes them ideally suited for extracellular and for intracellular delivery, in vitro as well as in vivo.