Cutting edge: Lipid raft integrity affects the efficiency of MHC class I tetramer binding and cell surface TCR arrangement on CD8(+) T cells

Physically distinct cholesterol/sphingolipid-rich plasma membrane microdoma ins, so-called lipid rafts, have been recognized to play an important regul atory role in various cellular processes, from membrane trafficking to sign al transduction, in a number of cell types. We report here that the ability of TCR on activated, functional CD8(+) T lymphocytes to efficiently bind M HC class I tetramer complexes is dependent on the integrity of lipid rafts on the T lymphocyte membrane. We further provide evidence that TCR interact (associate) with lipid raft elements on the T cell surface before receptor engagement and that the topological arrangement of TCR on the cell surface is likewise influenced by lipid raft integrity.