Authors: N. Anikeeva, D. Gakamsky, Yu. Sykulev
Affilation: Thomas Jefferson University, United States
Pages: 443 - 446
Keywords: quantum dots, antigen recognition by T cells, proximity between immune receptors
We utilized quantum dots (QD) as a unique nanoscaffold with uniform size and well-defined structure to assemble membrane immune receptors on the surface of the dots at desired density. Such QD/receptor biosensors appear to be a useful tool to probe organization of membrane receptor clusters, ligand recognition, and receptor mediated intracellular signaling. Based on our previous findings, we propose that the proximity of the immune receptors facilitates very sensitive recognition of virus-infected cells by T cells. To test this hypothesis we have been measuring separating distances between peptide-MHC (pMHC) molecules recognizable by antigen specific T cell receptor (TCR) assembled on the surface of QD by mean of FRET between labeled MHC-associated peptides. Our data indicate that pMHC proteins on ODs are in very close proximity as opposed to the same pMHC assembled into the Streptavidin scaffold. This is consistent with much more potent T cell stimulatory activity of QD/pMHC than pMHC/Streptavidin.