FK-506 monohydrate (CAS 109581-93-3)

FK-506 monohydrate, also known as Tacrolimus monohydrate, is a potent immunosuppressive compound that plays a role in the field of immunology research. Its mechanism of action is primarily through the inhibition of calcineurin, a phosphatase enzyme pivotal in activating T-lymphocytes. By binding to the immunophilin FKBP-12 (FK506 binding protein), FK-506 forms a complex that specifically and competitively inhibits calcineurin, leading to a decrease in the transcription of interleukin-2 and other cytokines, which are essential for the activation of T-cell-mediated immune responses. This mechanism highlights its importance in studying the pathways of immune response and the modulation of immune reactions in various experimental models. The compound′s ability to precisely downregulate an overactive immune system without affecting the entirety of the body′s immune response makes it useful in research focused on autoimmune diseases, organ transplantation, and the body′s rejection of foreign cells. Its unique action on the calcineurin pathway also serves as a model for developing new immunosuppressive agents with improved efficacy and specificity, underscoring its significance in advancing our understanding of immune system regulation and intervention strategies in research applications.