video: Dissociation of StrepTactin and monomerized MHC from individual living T cells in separate fluorescence channels. Individual Streptamer stained T cells before and after the addition of D-biotin in the koff-rate assay setup. The Strep-Tactin APC fluorescence (blue, left) and the Atto565 fluorescence of MHC molecules are displayed in separated channels for each cell (cell 1 – cell 4). After addition of D-biotin the Strep-Tactin APC fluorescence is lost rapidly, while Atto565 fluorescence of the MHC molecules increases as it is no longer absorbed by the APC dye. Thereafter Atto565 fluorescence decreases with the dissociation of monomeric MHC molecules from the T cell surface until complete loss of fluorescence. This video relates to a paper that appeared in the July 3, 2013, issue of Science Translational Medicine, published by AAAS. The paper, by M. Nauerth at Technische Universität München in Munich, Germany, and colleagues was titled, “TCR-Ligand koff-Rate Correlates with the Protective Capacity of Antigen-Specific CD8+ T Cells for Adoptive Transfer.” view more
Credit: Video courtesy of <i>Science Translational Medicine</i>/AAAS