Tacrolimus (FK506, Fujimycin) is a macrolide immunosuppressant that binds to FKBP12 to form a high-affinity complex (Ki = 0.2 nM), which inhibits calcineurin phosphatase activity, thereby suppressing T lymphocyte signal transduction and the transcription and release of IL-2. It exerts potent immunosuppressive effects and can be used to induce immunosuppression models.
