Anti-Ms NK1.1 (CD161), PK136, FI, 25µg

This FITC-conjugated monoclonal antibody from STEMCELL Technologies, clone PK136, is a mouse IgG2a kappa reagent directed against murine NK1.1 (CD161), an approximately 80 kDa homodimeric type 2 transmembrane glycoprotein and C-type lectin receptor. The antigen, also known by alternative names including NKR-P1, Ly-55, and Ly-59, is expressed on NK cells, NK-T cells, and rare subsets of T cells and monocytes in select mouse strains. NK1.1 is encoded by the Klrb1b and Klrb1c genes, which specify the CD161b and CD161c polypeptides; CD161b is expressed only by Swiss NIH and SJL mice, while CD161c is found in strains such as C57BL, FVB/N, and NZB (but not A, AKR, BALB/c, CBA/J, C3H, C57BR, C58, DBA/1, DBA/2, NOD, SJL, or 129).

The antibody was raised against NK-1+ cells from mouse spleen and bone marrow in a (C3H x BALB/c) F1 hybrid host, purified by affinity chromatography, and supplied in phosphate-buffered saline (pH 7.2) containing 0.09% sodium azide and 0.1% gelatin. NK1.1 modulates NK cell activation and proliferation, the induction of interferon-γ production, and the release of cytotoxic granules, and its cell-surface expression is specifically upregulated by IL-12. Verified for flow cytometry and reported for immunofluorescence and immunohistochemistry, the reagent has been used to assess the purity of cells isolated from NK1.1+ strains including C57BL/6, FVB/N, NZB, Swiss NIH, and SJL with EasySep kits. For NK1.1- strains, an Anti-Mouse CD49b antibody, clone DX5, is recommended as an alternative NK cell marker.

For flow cytometry, the manufacturer suggests ≤ 0.5 μg per 1 x 10^6 cells in 100 μL, with titration recommended for each application. The product is stable at 2–8 °C when stored undiluted; it should not be frozen, must be protected from prolonged exposure to light, and remains stable until the expiry date on the label. For research use only.