CHAPTER 10: In Vitro Evolution and Aptamers^†

We present here the fundamentals of aptamer selection, beginning with the original in vitro systematic evolution of ligands by exponential enrichment (SELEX) protocol, first described in 1990, and culminating in recent advances in aptamer selection methodologies that have fast-tracked the development of aptamers for several research and therapeutic applications. These include advances in chemistries to impart stability and reduce toxicity, methodologies that have enabled the identification of aptamers to more complex targets and novel technologies such as next-generation sequencing (NGS), to fast-track the selection process and to provide a more complete in silico analysis of aptamer sequence families and their functional properties. We have highlighted applications of aptamers as research tools and as unique reagents for diagnostic and therapeutic applications. We have concluded this survey with an overview of those aptamers that have undergone clinical development and/or evaluation and have discussed the applications of this new class of chemically-modified oligonucleotides as potential diagnostics and therapeutics for a variety of clinical indications. We believe that aptamers constitute a research field with great potential for future advances.