Partially Robotic Selection of Aptamers to Red Blood Cell Protein Glycophorin A

Abstract

Aptamers are small DNA ligands that have been manually selected to strongly and specifically bind a target of interest. These molecules may prove superior to modern antibodies in a number of ways including price and reproducibility. One of the major advantages of using aptamers as opposed to antibodies is the relative speed of development. This, coupled with the repetitive nature of aptamer selection, means that the entire process is a possible target for automation. In the following experiments, a ssDNA aptamer is developed against the human red blood cell protein glycophorin A, partially through the novel use of a robotized benchtop. The process also utilizes an adapted protocol for emulsion PCR to further increase the efficiency of the selection process. After 11 rounds of selection, the DNA pools were sequenced leading to the generation of 14 potential aptamers. These aptamers were tested with the isolated protein and with human red blood cells resulting in several of the aptamers being deemed potential binders. Further work with these identified sequences could result in aptamers that can be reliably used to tag and delicately separate red blood cells from other cells of interest within blood, such as stem cells. The novel approaches to selection used in this work may also lead to quicker and more efficient generation of future aptamers.