CD8 is a cell surface glycoprotein found on most cytotoxic T lymphocytes that mediates efficient cell-cell interactions within immune system. CD8 acts as a coreceptor with T cell receptor on T lymphocyte to recognize antigens displayed by antigen presenting cell in the context MHC II molecules. 10%-30% human lymphocytes are CD8 positive. Human CD8 Isolation Kit is designed to isolate untouched CD8+ T toxicity lymphocytes which contains a biotin labeled antibody cocktail and streptavidin conjugated magnetic beads. Through incubation of samples with biotin antibody cocktail followed by incubation of streptavidin beads, the magnetically labeled non CD8+ cells will be retained in the tube by magnetic separator. The untouched CD8+ T toxicity cells are collected in supernatant. Any downstream application can be performed on CD8+ cells after separation, such as Flow Cytometry and in vitro culture.