Glioblastoma or grade IV glioma is characterized by extremely poor prognosis. Resistance to radio- / chemotherapy and recurrences are associated with tumor stem cells. Transmembrane protein CD133 is considered a potential marker of tumor stem cells. To overcome the limitations of detecting cellular CD133 by antibodies, potential of aptamers (nucleic acid-based molecular recognition elements) is being explored. To obtain reproducible results, it is necessary to study the interaction of fluorescent aptamers to CD133 with standard cell lines and cell cultures derived from patient tumors using various methods.

OBJECTIVE

To detect the CD133 marker in continuous cell cultures of patient-derived GB cells using fluorescent DNA aptamers by flow cytometry.

MATERIAL AND METHODS

Fluorescein (FAM)-labeled DNA aptamers of the Cs and Ap series were used to detect the CD133 marker. Three continuous cell cultures from the Burdenko Neurosurgical Center Biobank were tested using flow cytometry. Burdenko: BU881 (107), G01, and Sus (harvested from postoperative GB tissues).

RESULTS

CD133 DNA aptamers at a concentration of 1 μM yield positive signals for GB cell cultures. Their magnitude correlates with CD133 gene transcription. Fluorescence signal shift (∆MFI) for FAM DNA aptamers of the Cs and Ap series is greater for BU881 cells (1942 and 5449 c.u., respectively) than for G01 cells (1469 and 1817 c.u., respectively). This is consistent with CD133 gene transcription. There is no fluorescence signal shift for Sus cells with minimal CD133 gene transcription.

CONCLUSION

Fluorescein-labeled DNA aptamers of the Cs and Ap series at a concentration of 1 μM enable detection of the CD133 marker in continuous cell cultures of GB through flow cytometry.