Cell-based assay for sensitive and specific detection of undifferentiated cells in stem cell-related research and development.
- Nanotechnology-based assay can detect residual undifferentiated cells and characterize cultures that may be tumorigenic.
- Technology is potentially more sensitive method compared to current methods.
Human pluripotent stem cells (hPSCs) have emerged as a potentially invaluable resource for cell therapy and regenerative medicine. A major concern is the potential risk for residual undifferentiated stem cells in preparations of hPSC derivatives to multiply and form a tumor upon transplantation. Existing cell-based assays including flow cytometry lack adequate sensitivity (>0.1%) to meet the stringent safety standard for stem cell products, thus requiring the development of a cell-based assay with high sensitivity and specificity.
Current cell-based assays provide inadequate sensitivity to assess potential risk of tumor formation in hPSC products. Researchers at Emory have developed a nanotechnology-based assay for the detection of residual undifferentiated stem cells. The assay uses surface enhanced Raman scattering nanoparticles (SERS), which are conjugated to antibodies against the pluripotency surface marker (TRA1-60) and modified for improved detection. The TRA1-60-SERS assay is able to detect stem cells in a cell mixture containing 0.01% stem cells. The high sensitivity and specificity of this SERS assay makes it a useful tool for transplantation of hPSC-derived production and characterization of differentiation cultures at various stages for risk of tumor development.