Work

Y-shaped trivalent aptamer for targeted visualization and tracking of reprogrammed astrocytes

Year: 2025

Type: article

Abstract: Despite extensive research into the diverse transformations and functions of astrocytes, conventional fluorescence immunohistochemistry for their distinct identification remains challenging and time-consuming, primarily due to the lack of cell surface binders specific to these glial cells. To address this limitation, we developed a specific and straightforward imaging strategy for primary astrocytes using cell surface-targeting aptamers. We identified a novel anti-astrocyte DNA aptamer (designated Ast17-30) through a 17-round cell-SELEX process incorporating magnetic-activated cell sorting, designed to bypass the technical hurdles of SELEX when applied to short-lived cells. To enhance binding affinity, we further engineered this aptamer into a Y-shaped trimer (Tri-ΔAst17-30), enabling clear discrimination between astrocytes and neurons. Consequently, the engineered trivalent aptamer facilitated rapid astrocyte-specific endocytosis within minutes due to its increased binding avidity. This capability enabled longitudinal monitoring of astrocyte conversion into induced neural precursor cells, observing moderate pro-inflammatory gene expression in their transcriptomic profiles. Furthermore, Tri-ΔAst17-30 bound strongly to astrocytic glioblastoma cells (U87MG), with minimal binding to glial glioblastoma cells (C6), confirming specificity for astrocytic tumor cells. Given the current absence of reliable live-astrocyte-specific imaging techniques, we propose that this trivalent anti-astrocyte DNA aptamer has potential for investigating developmental pathways and targeted therapy of these crucial glial cells.

Source: Materials Today Bio

DOI: 10.1016/j.mtbio.2025.102482