Selection of DNA Aptamers for Differentiation of Human Adipose-Derived Mesenchymal Stem Cells from Fibroblasts.

In recent years, stem cell therapy has shown promise in regenerative medicine. The lack of standardized protocols for cell isolation and differentiation generates conflicting results in this field. Mesenchymal stem cells derived from adipose tissue (ASC) and fibroblasts (FIB) share very similar cell membrane markers. In this context, the distinction of mesenchymal stem cells from fibroblasts has been crucial for safe clinical application of these cells. In the present study, we developed aptamers capable of specifically recognize ASC using the Cell-SELEX technique. We tested the affinity of ASC aptamers compared to dermal FIB. Quantitative PCR was advantageous for the in vitro validation of four candidate aptamers. The binding capabilities of Apta 2 and Apta 42 could not distinguish both cell types. At the same time, Apta 21 and Apta 99 showed a better binding capacity to ASC with dissociation constants (Kd) of 50.46 ± 2.28 nM and 72.71 ± 10.3 nM, respectively. However, Apta 21 showed a Kd of 86.78 ± 9.14 nM when incubated with FIB. Therefore, only Apta 99 showed specificity to detect ASC by total internal reflection microscopy (TIRF). This aptamer is a promising tool for the in vitro identification of ASC. These results will help understand the differences between these two cell types for more specific and precise cell therapies.