Murine epidermal γ/δ T cells express Fcγ receptor II encoded by the FcγRα α gene

Short-term bulk cultures and some long-term clones and lines of murine T cell receptor (TcR) gamma/delta-bearing epidermal T cells (dEC) were found to express an Fc gamma receptor II (Fc gamma RII), as revealed by reactivity with the monoclonal antibody 2.4G2. Northern blot analysis showed that the Fc gamma RII expressed on dEC is encoded solely by the Fc gamma R alpha gene. While all the various cultured dEC cell populations analyzed exhibit lectin-dependent cellular cytotoxicity, only those which expressed Fc gamma R alpha were also capable of mediating antibody-dependent cellular cytotoxicity (ADCC). These results in combination with the previous demonstration of Fc gamma R alpha on mouse natural killer cells support an essential role for Fc gamma R alpha in ADCC and extend an analogy with surface CD16 (Fc gamma RIII) expression and ADCC in human natural killer cells and peripheral TcR gamma/delta T cells.