Pharmacodynamic monitoring of the immunosuppressive therapy in patients after heart transplantation: Whole blood flow cytometric analysis of lymphocyte function

Despite therapeutic monitoring and daily measurements of blood concentrations (pharmacokinetics) of immunosuppressive medications, immunosuppressive therapy remains still a challenge after heart transplantation (HTx) due to drug interactions, toxicities and individual responses to drug effects. We established whole blood flow cytometric assays of lymphocyte function to assess the pharmacodynamics of immunosuppressive therapy and investigated both pharmacokinetic and pharmacodynamic approaches after HTx. Our results showed that pharmacodynamic measurements provide a more direct assessment of the functional activity of immunosuppressants on immune cells compared to drug level monitoring alone. The information from both pharmacokinetic and pharmacodynamic monitoring has the potential to increase the efficacy and safety of individual immunosuppressive therapy after HTx.