Description: The PK136 monoclonal antibody reacts with mouse NK1.1, an antigen expressed by natural killer cells and a subset of T cells in the NK1.1 mouse strains including C57BL and NZB. Several commonly used laboratory mouse strains such as BALB/c, SJL, AKR, CBA, C3H and A do not express the NK1.1 antigen. For detection of NK cells in these strains the monoclonal antibody DX5 (Product # 14-5971) should be used. Simultaneous staining of C57BL/6 spleen cells with PK136 and DX5 reveals coexpression of both markers by a majority of cells as well as presence of small populations of DX5+PK136- and DX5-PK136+ cells. Applications Reported: PK136 has been reported for use in flow cytometric analysis. Applications Tested: The PK136 antibody has been tested by flow cytometric analysis of C57Bl/6 mouse splenocytes and can be used at less than or equal to 0.125 μg per test. A test is defined as the amount (μg) of antibody that will stain a cell sample in a final volume of 100 μL. Cell number should be determined empirically but can range from 10^5 to 10^8 cells/test. It is recommended that the antibody be carefully titrated for optimal performance in the assay of interest. Excitation: 633-647 nm; Emission: 660 nm; Laser: Red Laser. Filtration: 0.2 μm post-manufacturing filtered.