Cell surface-camouflaged graphene oxide immunosensor for identifying immune reactions

Abstract

Monitoring the intensity of immune reactions is very useful to diagnose the fate of transplanted cells. For directly monitoring immune reactions after pancreatic islet cell transplantation, here graphene oxide (GO) quencher was chemically conjugated with fluorescence dye via Granzyme B (GrB)-specific peptide, so called to GO-based immunosensor. GO-based immunosensor was stably immobilized onto surface of living cells without damage of viability and functionality. The cell-surface camouflaged GO-based immunosensor could detect GrB (> 2 unit/ml) secreted from immune cells, thereby dequenching fluorescence. Collectively, we anticipated that the GO-based immunosensor could be utilized to monitor cell graft rejection after cell therapy in vivo.