A novel MHC- dextramer assay to identify melanoma antigen-specific CD8+ T cells from solid tumor disaggregates and matched peripheral blood.

Background Cytotoxic CD8 T lymphocytes (CTL) mediate target cell killing of tumor cells. New technological advances in multi-parameter flow cytometry have enabled the detection and enumeration of antigen-specific CD8 T cells (MHC-class I dextramer staining) in peripheral blood. A new dextramer based IVD test has been approved in Europe for the quantification of CMV specific CD8 T cells in peripheral blood. However, the feasibility of this type of assay in other relevant sample types such solid tumors to interrogate tumor-infiltrating lymphocytes has not yet been established.