From the SENS Foundation: "Aggregates of beta-amyloid (Abeta) and other malformed proteins accumulate in brain aging and neurodegenerative disease, leading progressively to neuronal dysfunction and/or loss. The regenerative engineering solution to these insults is therapeutic clearance of aggregates, extracellular (such as Abeta plaques) and intracellular (such as soluble, oligomeric Abeta). Immunotherapeutic Abeta clearance from the brain is a very active field of Alzheimer's research, with at least seven passive, and several second-generation active, Abeta vaccines currently in human clinical trials ... One challenge to optimal vaccine design is matching the specificity of antibodies the range of Abeta aggregates that form in vivo ... agents that sequester one Abeta species may leave other species intact, and in some cases a shift in assembly dynamics can actually promote the formation of one species while clearing or reducing the formation of others ... Although in very early in vivo testing, a new approach has emerged that may offer that promise. This is the use of an Abeta-targeting affibody, i.e., a novel non-immunoglobulin binding protein generated through combinatorial protein engineering."